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others. Maintained by: Olaf Bachmann <obachman@mathematik.uni-kl.de> Send bugs and suggestions to <texi2html@mathematik.uni-kl.de> --> <HEAD> <TITLE>The Red Hat newlib C Math Library: </TITLE> <META NAME="description" CONTENT="The Red Hat newlib C Math Library: "> <META NAME="keywords" CONTENT="The Red Hat newlib C Math Library: "> <META NAME="resource-type" CONTENT="document"> <META NAME="distribution" CONTENT="global"> <META NAME="Generator" CONTENT="texi2html 1.64"> </HEAD> <BODY LANG="" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#800080" ALINK="#FF0000"> <h1>The Red Hat newlib C Math Library: </h1> <h2>Full Configuration</h2> <h2><code>libm</code> 1.11.0</h2> <h2>May, 2 2003 </h2> <address>{Steve Chamberlain}</address> <address>{Roland Pesch}</address> <address>{Red Hat Support}</address> <address>{Jeff Johnston}</address> <p> <p><hr><p> <A NAME="SEC1"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC2"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <P> <BLOCKQUOTE><TABLE BORDER=0 CELLSPACING=0> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC1">1. Mathematical Functions (<TT>`math.h'</TT>)</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">The mathematical functions (`math.h').</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC42">2. Reentrancy Properties of <CODE>libm</CODE></A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">The functions in libm are not reentrant by default.</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC43">Index</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP"></TD></TR> </TABLE></BLOCKQUOTE> <P> <A NAME="Math"></A> <H1> 1. Mathematical Functions (<TT>`math.h'</TT>) </H1> <!--docid::SEC1::--> <P> This chapter groups a wide variety of mathematical functions. The corresponding definitions and declarations are in <TT>`math.h'</TT>. Two definitions from <TT>`math.h'</TT> are of particular interest. </P><P> <OL> <LI> The representation of infinity as a <CODE>double</CODE> is defined as <CODE>HUGE_VAL</CODE>; this number is returned on overflow by many functions. <P> <LI> The structure <CODE>exception</CODE> is used when you write customized error handlers for the mathematical functions. You can customize error handling for most of these functions by defining your own version of <CODE>matherr</CODE>; see the section on <CODE>matherr</CODE> for details. </OL> <P> <A NAME="IDX1"></A> <A NAME="IDX2"></A> <A NAME="IDX3"></A> <A NAME="IDX4"></A> Since the error handling code calls <CODE>fputs</CODE>, the mathematical subroutines require stubs or minimal implementations for the same list of OS subroutines as <CODE>fputs</CODE>: <CODE>close</CODE>, <CODE>fstat</CODE>, <CODE>isatty</CODE>, <CODE>lseek</CODE>, <CODE>read</CODE>, <CODE>sbrk</CODE>, <CODE>write</CODE>. See section `System Calls' in <CITE>The Cygnus C Support Library</CITE>, for a discussion and for sample minimal implementations of these support subroutines. </P><P> Alternative declarations of the mathematical functions, which exploit specific machine capabilities to operate faster--but generally have less error checking and may reflect additional limitations on some machines--are available when you include <TT>`fastmath.h'</TT> instead of <TT>`math.h'</TT>. </P><P> <BLOCKQUOTE><TABLE BORDER=0 CELLSPACING=0> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC2">1.1 Version of library</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP"></TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC3">1.2 <CODE>acos</CODE>, <CODE>acosf</CODE>---arc cosine</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Arccosine</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC4">1.3 <CODE>acosh</CODE>, <CODE>acoshf</CODE>---inverse hyperbolic cosine</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Inverse hyperbolic cosine</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC5">1.4 <CODE>asin</CODE>, <CODE>asinf</CODE>---arc sine</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Arcsine</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC6">1.5 <CODE>asinh</CODE>, <CODE>asinhf</CODE>---inverse hyperbolic sine</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Inverse hyperbolic sine</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC7">1.6 <CODE>atan</CODE>, <CODE>atanf</CODE>---arc tangent</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Arctangent</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC8">1.7 <CODE>atan2</CODE>, <CODE>atan2f</CODE>---arc tangent of y/x</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Arctangent of y/x</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC9">1.8 <CODE>atanh</CODE>, <CODE>atanhf</CODE>---inverse hyperbolic tangent</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Inverse hyperbolic tangent</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Bessel functions (jN, yN)</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC31">1.30 <CODE>cbrt</CODE>, <CODE>cbrtf</CODE>---cube root</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Cube root</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC32">1.31 <CODE>copysign</CODE>, <CODE>copysignf</CODE>---sign of <VAR>y</VAR>, magnitude of <VAR>x</VAR></A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Sign of Y, magnitude of X</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC11">1.10 <CODE>cosh</CODE>, <CODE>coshf</CODE>---hyperbolic cosine</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Hyperbolic cosine</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC12">1.11 <CODE>erf</CODE>, <CODE>erff</CODE>, <CODE>erfc</CODE>, <CODE>erfcf</CODE>---error function</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Error function (erf, erfc)</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC13">1.12 <CODE>exp</CODE>, <CODE>expf</CODE>---exponential</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Exponential</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC33">1.32 <CODE>expm1</CODE>, <CODE>expm1f</CODE>---exponential minus 1</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Exponential of x, - 1</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC14">1.13 <CODE>fabs</CODE>, <CODE>fabsf</CODE>---absolute value (magnitude)</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Absolute value (magnitude)</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC15">1.14 <CODE>floor</CODE>, <CODE>floorf</CODE>, <CODE>ceil</CODE>, <CODE>ceilf</CODE>---floor and ceiling</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Floor and ceiling (floor, ceil)</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC16">1.15 <CODE>fmod</CODE>, <CODE>fmodf</CODE>---floating-point remainder (modulo)</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Floating-point remainder (modulo)</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC17">1.16 <CODE>frexp</CODE>, <CODE>frexpf</CODE>---split floating-point number</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Split floating-point number</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC18">1.17 <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, <CODE>lgammaf</CODE>, <CODE>gamma_r</CODE>,</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Logarithmic gamma function</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC19">1.18 <CODE>hypot</CODE>, <CODE>hypotf</CODE>---distance from origin</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Distance from origin</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC34">1.33 <CODE>ilogb</CODE>, <CODE>ilogbf</CODE>---get exponent of floating point number</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Get exponent</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC35">1.34 <CODE>infinity</CODE>, <CODE>infinityf</CODE>---representation of infinity</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Floating infinity</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC20">1.19 <CODE>isnan</CODE>,<CODE>isnanf</CODE>,<CODE>isinf</CODE>,<CODE>isinff</CODE>,<CODE>finite</CODE>,<CODE>finitef</CODE>---test for exceptional numbers</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Check type of number</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC21">1.20 <CODE>ldexp</CODE>, <CODE>ldexpf</CODE>---load exponent</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Load exponent</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC22">1.21 <CODE>log</CODE>, <CODE>logf</CODE>---natural logarithms</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Natural logarithms</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC23">1.22 <CODE>log10</CODE>, <CODE>log10f</CODE>---base 10 logarithms</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Base 10 logarithms</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC36">1.35 <CODE>log1p</CODE>, <CODE>log1pf</CODE>---log of <CODE>1 + <VAR>x</VAR></CODE></A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Log of 1 + X</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC37">1.36 <CODE>matherr</CODE>---modifiable math error handler</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Modifiable math error handler</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC38">1.37 <CODE>modf</CODE>, <CODE>modff</CODE>---split fractional and integer parts</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Split fractional and integer parts</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC39">1.38 <CODE>nan</CODE>, <CODE>nanf</CODE>---representation of infinity</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Floating Not a Number</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC40">1.39 <CODE>nextafter</CODE>, <CODE>nextafterf</CODE>---get next number</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Get next representable number</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC24">1.23 <CODE>pow</CODE>, <CODE>powf</CODE>---x to the power y</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">X to the power Y</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC25">1.24 <CODE>remainder</CODE>, <CODE>remainderf</CODE>---round and remainder</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">remainder of X divided by Y</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC41">1.40 <CODE>scalbn</CODE>, <CODE>scalbnf</CODE>---scale by integer</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">scalbn</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC27">1.26 <CODE>sin</CODE>, <CODE>sinf</CODE>, <CODE>cos</CODE>, <CODE>cosf</CODE>---sine or cosine</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Sine or cosine (sin, cos)</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC28">1.27 <CODE>sinh</CODE>, <CODE>sinhf</CODE>---hyperbolic sine</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Hyperbolic sine</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC26">1.25 <CODE>sqrt</CODE>, <CODE>sqrtf</CODE>---positive square root</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Positive square root</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC29">1.28 <CODE>tan</CODE>, <CODE>tanf</CODE>---tangent</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Tangent</TD></TR> <TR><TD ALIGN="left" VALIGN="TOP"><A HREF="libm.html#SEC30">1.29 <CODE>tanh</CODE>, <CODE>tanhf</CODE>---hyperbolic tangent</A></TD><TD> </TD><TD ALIGN="left" VALIGN="TOP">Hyperbolic tangent</TD></TR> </TABLE></BLOCKQUOTE> <P> <A NAME="version"></A> <HR SIZE="6"> <A NAME="SEC2"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC3"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.1 Version of library </H2> <!--docid::SEC2::--> <P> There are four different versions of the math library routines: IEEE, POSIX, X/Open, or SVID. The version may be selected at runtime by setting the global variable <CODE>_LIB_VERSION</CODE>, defined in <TT>`math.h'</TT>. It may be set to one of the following constants defined in <TT>`math.h'</TT>: <CODE>_IEEE_</CODE>, <CODE>_POSIX_</CODE>, <CODE>_XOPEN_</CODE>, or <CODE>_SVID_</CODE>. The <CODE>_LIB_VERSION</CODE> variable is not specific to any thread, and changing it will affect all threads. </P><P> The versions of the library differ only in how errors are handled. </P><P> In IEEE mode, the <CODE>matherr</CODE> function is never called, no warning messages are printed, and <CODE>errno</CODE> is never set. </P><P> In POSIX mode, <CODE>errno</CODE> is set correctly, but the <CODE>matherr</CODE> function is never called and no warning messages are printed. </P><P> In X/Open mode, <CODE>errno</CODE> is set correctly, and <CODE>matherr</CODE> is called, but warning message are not printed. </P><P> In SVID mode, functions which overflow return 3.40282346638528860e+38, the maximum single precision floating point value, rather than infinity. Also, <CODE>errno</CODE> is set correctly, <CODE>matherr</CODE> is called, and, if <CODE>matherr</CODE> returns 0, warning messages are printed for some errors. For example, by default <SAMP>`log(-1.0)'</SAMP> writes this message on standard error output: </P><P> <TABLE><tr><td> </td><td class=example><pre>log: DOMAIN error </pre></td></tr></table></P><P> The library is set to X/Open mode by default. </P><P> <A NAME="acos"></A> <HR SIZE="6"> <A NAME="SEC3"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC2"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC4"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.2 <CODE>acos</CODE>, <CODE>acosf</CODE>---arc cosine </H2> <!--docid::SEC3::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double acos(double <VAR>x</VAR>); float acosf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <P> <CODE>acos</CODE> computes the inverse cosine (arc cosine) of the input value. Arguments to <CODE>acos</CODE> must be in the range -1 to 1. </P><P> <CODE>acosf</CODE> is identical to <CODE>acos</CODE>, except that it performs its calculations on <CODE>floats</CODE>. </P><P> <BR> <STRONG>Returns</STRONG><BR> </P><P> If <VAR>x</VAR> is not between -1 and 1, the returned value is NaN (not a number) the global variable <CODE>errno</CODE> is set to <CODE>EDOM</CODE>, and a <CODE>DOMAIN error</CODE> message is sent as standard error output. </P><P> You can modify error handling for these functions using <CODE>matherr</CODE>. </P><P> <BR> </P><P> <A NAME="acosh"></A> <HR SIZE="6"> <A NAME="SEC4"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC3"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC5"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.3 <CODE>acosh</CODE>, <CODE>acoshf</CODE>---inverse hyperbolic cosine </H2> <!--docid::SEC4::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double acosh(double <VAR>x</VAR>); float acoshf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>acosh</CODE> calculates the inverse hyperbolic cosine of <VAR>x</VAR>. <CODE>acosh</CODE> is defined as <P> <VAR>x</VAR> must be a number greater than or equal to 1. </P><P> <CODE>acoshf</CODE> is identical, other than taking and returning floats. </P><P> <BR> <STRONG>Returns</STRONG><BR> <CODE>acosh</CODE> and <CODE>acoshf</CODE> return the calculated value. If <VAR>x</VAR> less than 1, the return value is NaN and <CODE>errno</CODE> is set to <CODE>EDOM</CODE>. </P><P> You can change the error-handling behavior with the non-ANSI <CODE>matherr</CODE> function. </P><P> <BR> <STRONG>Portability</STRONG><BR> Neither <CODE>acosh</CODE> nor <CODE>acoshf</CODE> are ANSI C. They are not recommended for portable programs. </P><P> <BR> </P><P> <A NAME="asin"></A> <HR SIZE="6"> <A NAME="SEC5"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC4"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC6"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.4 <CODE>asin</CODE>, <CODE>asinf</CODE>---arc sine </H2> <!--docid::SEC5::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double asin(double <VAR>x</VAR>); float asinf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <P> <CODE>asin</CODE> computes the inverse sine (arc sine) of the argument <VAR>x</VAR>. Arguments to <CODE>asin</CODE> must be in the range -1 to 1. </P><P> <CODE>asinf</CODE> is identical to <CODE>asin</CODE>, other than taking and returning floats. </P><P> You can modify error handling for these routines using <CODE>matherr</CODE>. </P><P> <BR> <STRONG>Returns</STRONG><BR> </P><P> If <VAR>x</VAR> is not in the range -1 to 1, <CODE>asin</CODE> and <CODE>asinf</CODE> return NaN (not a number), set the global variable <CODE>errno</CODE> to <CODE>EDOM</CODE>, and issue a <CODE>DOMAIN error</CODE> message. </P><P> You can change this error treatment using <CODE>matherr</CODE>. </P><P> <BR> </P><P> <A NAME="asinh"></A> <HR SIZE="6"> <A NAME="SEC6"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC5"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC7"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.5 <CODE>asinh</CODE>, <CODE>asinhf</CODE>---inverse hyperbolic sine </H2> <!--docid::SEC6::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double asinh(double <VAR>x</VAR>); float asinhf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>asinh</CODE> calculates the inverse hyperbolic sine of <VAR>x</VAR>. <CODE>asinh</CODE> is defined as <P> <CODE>asinhf</CODE> is identical, other than taking and returning floats. </P><P> <BR> <STRONG>Returns</STRONG><BR> <CODE>asinh</CODE> and <CODE>asinhf</CODE> return the calculated value. </P><P> <BR> <STRONG>Portability</STRONG><BR> Neither <CODE>asinh</CODE> nor <CODE>asinhf</CODE> are ANSI C. </P><P> <BR> </P><P> <A NAME="atan"></A> <HR SIZE="6"> <A NAME="SEC7"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC6"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC8"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.6 <CODE>atan</CODE>, <CODE>atanf</CODE>---arc tangent </H2> <!--docid::SEC7::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double atan(double <VAR>x</VAR>); float atanf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <P> <CODE>atan</CODE> computes the inverse tangent (arc tangent) of the input value. </P><P> <CODE>atanf</CODE> is identical to <CODE>atan</CODE>, save that it operates on <CODE>floats</CODE>. </P><P> <BR> <STRONG>Returns</STRONG><BR> </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>atan</CODE> is ANSI C. <CODE>atanf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="atan2"></A> <HR SIZE="6"> <A NAME="SEC8"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC7"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC9"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.7 <CODE>atan2</CODE>, <CODE>atan2f</CODE>---arc tangent of y/x </H2> <!--docid::SEC8::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double atan2(double <VAR>y</VAR>,double <VAR>x</VAR>); float atan2f(float <VAR>y</VAR>,float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <P> <CODE>atan2</CODE> computes the inverse tangent (arc tangent) of <VAR>y</VAR>/<VAR>x</VAR>. <CODE>atan2</CODE> produces the correct result even for angles near (that is, when <VAR>x</VAR> is near 0). </P><P> <CODE>atan2f</CODE> is identical to <CODE>atan2</CODE>, save that it takes and returns <CODE>float</CODE>. </P><P> <BR> <STRONG>Returns</STRONG><BR> <CODE>atan2</CODE> and <CODE>atan2f</CODE> return a value in radians, in the range of </P><P> If both <VAR>x</VAR> and <VAR>y</VAR> are 0.0, <CODE>atan2</CODE> causes a <CODE>DOMAIN</CODE> error. </P><P> You can modify error handling for these functions using <CODE>matherr</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>atan2</CODE> is ANSI C. <CODE>atan2f</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="atanh"></A> <HR SIZE="6"> <A NAME="SEC9"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC8"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC10"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.8 <CODE>atanh</CODE>, <CODE>atanhf</CODE>---inverse hyperbolic tangent </H2> <!--docid::SEC9::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double atanh(double <VAR>x</VAR>); float atanhf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>atanh</CODE> calculates the inverse hyperbolic tangent of <VAR>x</VAR>. <P> <CODE>atanhf</CODE> is identical, other than taking and returning <CODE>float</CODE> values. </P><P> <BR> <STRONG>Returns</STRONG><BR> <CODE>atanh</CODE> and <CODE>atanhf</CODE> return the calculated value. </P><P> If is greater than 1, the global <CODE>errno</CODE> is set to <CODE>EDOM</CODE> and the result is a NaN. A <CODE>DOMAIN error</CODE> is reported. </P><P> If is 1, the global <CODE>errno</CODE> is set to <CODE>EDOM</CODE>; and the result is infinity with the same sign as <CODE>x</CODE>. A <CODE>SING error</CODE> is reported. </P><P> You can modify the error handling for these routines using <CODE>matherr</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> Neither <CODE>atanh</CODE> nor <CODE>atanhf</CODE> are ANSI C. </P><P> <BR> </P><P> <A NAME="jN"></A> <HR SIZE="6"> <A NAME="SEC10"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC9"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC11"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions </H2> <!--docid::SEC10::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double j0(double <VAR>x</VAR>); float j0f(float <VAR>x</VAR>); double j1(double <VAR>x</VAR>); float j1f(float <VAR>x</VAR>); double jn(int <VAR>n</VAR>, double <VAR>x</VAR>); float jnf(int <VAR>n</VAR>, float <VAR>x</VAR>); double y0(double <VAR>x</VAR>); float y0f(float <VAR>x</VAR>); double y1(double <VAR>x</VAR>); float y1f(float <VAR>x</VAR>); double yn(int <VAR>n</VAR>, double <VAR>x</VAR>); float ynf(int <VAR>n</VAR>, float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> The Bessel functions are a family of functions that solve the differential equation These functions have many applications in engineering and physics. <P> <CODE>jn</CODE> calculates the Bessel function of the first kind of order <VAR>n</VAR>. <CODE>j0</CODE> and <CODE>j1</CODE> are special cases for order 0 and order 1 respectively. </P><P> Similarly, <CODE>yn</CODE> calculates the Bessel function of the second kind of order <VAR>n</VAR>, and <CODE>y0</CODE> and <CODE>y1</CODE> are special cases for order 0 and 1. </P><P> <CODE>jnf</CODE>, <CODE>j0f</CODE>, <CODE>j1f</CODE>, <CODE>ynf</CODE>, <CODE>y0f</CODE>, and <CODE>y1f</CODE> perform the same calculations, but on <CODE>float</CODE> rather than <CODE>double</CODE> values. </P><P> <BR> <STRONG>Returns</STRONG><BR> The value of each Bessel function at <VAR>x</VAR> is returned. </P><P> <BR> <STRONG>Portability</STRONG><BR> None of the Bessel functions are in ANSI C. </P><P> <BR> </P><P> <A NAME="cosh"></A> <HR SIZE="6"> <A NAME="SEC11"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC10"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC12"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.10 <CODE>cosh</CODE>, <CODE>coshf</CODE>---hyperbolic cosine </H2> <!--docid::SEC11::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double cosh(double <VAR>x</VAR>); float coshf(float <VAR>x</VAR>) </pre></td></tr></table><STRONG>Description</STRONG><BR> <P> <CODE>cosh</CODE> computes the hyperbolic cosine of the argument <VAR>x</VAR>. <CODE>cosh(<VAR>x</VAR>)</CODE> is defined as </P><P> Angles are specified in radians. <CODE>coshf</CODE> is identical, save that it takes and returns <CODE>float</CODE>. </P><P> <BR> <STRONG>Returns</STRONG><BR> The computed value is returned. When the correct value would create an overflow, <CODE>cosh</CODE> returns the value <CODE>HUGE_VAL</CODE> with the appropriate sign, and the global value <CODE>errno</CODE> is set to <CODE>ERANGE</CODE>. </P><P> You can modify error handling for these functions using the function <CODE>matherr</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>cosh</CODE> is ANSI. <CODE>coshf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="erf"></A> <HR SIZE="6"> <A NAME="SEC12"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC11"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC13"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.11 <CODE>erf</CODE>, <CODE>erff</CODE>, <CODE>erfc</CODE>, <CODE>erfcf</CODE>---error function </H2> <!--docid::SEC12::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double erf(double <VAR>x</VAR>); float erff(float <VAR>x</VAR>); double erfc(double <VAR>x</VAR>); float erfcf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>erf</CODE> calculates an approximation to the "error function", which estimates the probability that an observation will fall within <VAR>x</VAR> standard deviations of the mean (assuming a normal distribution). <P> <CODE>erfc</CODE> calculates the complementary probability; that is, <CODE>erfc(<VAR>x</VAR>)</CODE> is <CODE>1 - erf(<VAR>x</VAR>)</CODE>. <CODE>erfc</CODE> is computed directly, so that you can use it to avoid the loss of precision that would result from subtracting large probabilities (on large <VAR>x</VAR>) from 1. </P><P> <CODE>erff</CODE> and <CODE>erfcf</CODE> differ from <CODE>erf</CODE> and <CODE>erfc</CODE> only in the argument and result types. </P><P> <BR> <STRONG>Returns</STRONG><BR> For positive arguments, <CODE>erf</CODE> and all its variants return a probability--a number between 0 and 1. </P><P> <BR> <STRONG>Portability</STRONG><BR> None of the variants of <CODE>erf</CODE> are ANSI C. </P><P> <BR> </P><P> <A NAME="exp"></A> <HR SIZE="6"> <A NAME="SEC13"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC12"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC14"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.12 <CODE>exp</CODE>, <CODE>expf</CODE>---exponential </H2> <!--docid::SEC13::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double exp(double <VAR>x</VAR>); float expf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>exp</CODE> and <CODE>expf</CODE> calculate the exponential of <VAR>x</VAR>, that is, is the base of the natural system of logarithms, approximately 2.71828). <P> You can use the (non-ANSI) function <CODE>matherr</CODE> to specify error handling for these functions. </P><P> <BR> <STRONG>Returns</STRONG><BR> On success, <CODE>exp</CODE> and <CODE>expf</CODE> return the calculated value. If the result underflows, the returned value is <CODE>0</CODE>. If the result overflows, the returned value is <CODE>HUGE_VAL</CODE>. In either case, <CODE>errno</CODE> is set to <CODE>ERANGE</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>exp</CODE> is ANSI C. <CODE>expf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="fabs"></A> <HR SIZE="6"> <A NAME="SEC14"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC13"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC15"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.13 <CODE>fabs</CODE>, <CODE>fabsf</CODE>---absolute value (magnitude) </H2> <!--docid::SEC14::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double fabs(double <VAR>x</VAR>); float fabsf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>fabs</CODE> and <CODE>fabsf</CODE> calculate the absolute value (magnitude) of the argument <VAR>x</VAR>, by direct manipulation of the bit representation of <VAR>x</VAR>. <P> <BR> <STRONG>Returns</STRONG><BR> The calculated value is returned. No errors are detected. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>fabs</CODE> is ANSI. <CODE>fabsf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="floor"></A> <HR SIZE="6"> <A NAME="SEC15"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC14"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC16"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.14 <CODE>floor</CODE>, <CODE>floorf</CODE>, <CODE>ceil</CODE>, <CODE>ceilf</CODE>---floor and ceiling </H2> <!--docid::SEC15::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double floor(double <VAR>x</VAR>); float floorf(float <VAR>x</VAR>); double ceil(double <VAR>x</VAR>); float ceilf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>floor</CODE> and <CODE>floorf</CODE> find the nearest integer less than or equal to <VAR>x</VAR>. <CODE>ceil</CODE> and <CODE>ceilf</CODE> find the nearest integer greater than or equal to <VAR>x</VAR>. <P> <BR> <STRONG>Returns</STRONG><BR> <CODE>floor</CODE> and <CODE>ceil</CODE> return the integer result as a double. <CODE>floorf</CODE> and <CODE>ceilf</CODE> return the integer result as a float. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>floor</CODE> and <CODE>ceil</CODE> are ANSI. <CODE>floorf</CODE> and <CODE>ceilf</CODE> are extensions. </P><P> <BR> </P><P> <A NAME="fmod"></A> <HR SIZE="6"> <A NAME="SEC16"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC15"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC17"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.15 <CODE>fmod</CODE>, <CODE>fmodf</CODE>---floating-point remainder (modulo) </H2> <!--docid::SEC16::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double fmod(double <VAR>x</VAR>, double <VAR>y</VAR>) float fmodf(float <VAR>x</VAR>, float <VAR>y</VAR>) </pre></td></tr></table><STRONG>Description</STRONG><BR> The <CODE>fmod</CODE> and <CODE>fmodf</CODE> functions compute the floating-point remainder of <VAR>x</VAR>/<VAR>y</VAR> (<VAR>x</VAR> modulo <VAR>y</VAR>). <P> <BR> <STRONG>Returns</STRONG><BR> The <CODE>fmod</CODE> function returns the value for the largest integer <VAR>i</VAR> such that, if <VAR>y</VAR> is nonzero, the result has the same sign as <VAR>x</VAR> and magnitude less than the magnitude of <VAR>y</VAR>. </P><P> <CODE>fmod(<VAR>x</VAR>,0)</CODE> returns NaN, and sets <CODE>errno</CODE> to <CODE>EDOM</CODE>. </P><P> You can modify error treatment for these functions using <CODE>matherr</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>fmod</CODE> is ANSI C. <CODE>fmodf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="frexp"></A> <HR SIZE="6"> <A NAME="SEC17"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC16"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC18"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.16 <CODE>frexp</CODE>, <CODE>frexpf</CODE>---split floating-point number </H2> <!--docid::SEC17::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double frexp(double <VAR>val</VAR>, int *<VAR>exp</VAR>); float frexpf(float <VAR>val</VAR>, int *<VAR>exp</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> All non zero, normal numbers can be described as <VAR>m</VAR> * 2**<VAR>p</VAR>. <CODE>frexp</CODE> represents the double <VAR>val</VAR> as a mantissa <VAR>m</VAR> and a power of two <VAR>p</VAR>. The resulting mantissa will always be greater than or equal to <CODE>0.5</CODE>, and less than <CODE>1.0</CODE> (as long as <VAR>val</VAR> is nonzero). The power of two will be stored in <CODE>*</CODE><VAR>exp</VAR>. <P> <CODE>frexpf</CODE> is identical, other than taking and returning floats rather than doubles. </P><P> <BR> <STRONG>Returns</STRONG><BR> <CODE>frexp</CODE> returns the mantissa <VAR>m</VAR>. If <VAR>val</VAR> is <CODE>0</CODE>, infinity, or Nan, <CODE>frexp</CODE> will set <CODE>*</CODE><VAR>exp</VAR> to <CODE>0</CODE> and return <VAR>val</VAR>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>frexp</CODE> is ANSI. <CODE>frexpf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="gamma"></A> <HR SIZE="6"> <A NAME="SEC18"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC17"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC19"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.17 <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, <CODE>lgammaf</CODE>, <CODE>gamma_r</CODE>, </H2> <!--docid::SEC18::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double gamma(double <VAR>x</VAR>); float gammaf(float <VAR>x</VAR>); double lgamma(double <VAR>x</VAR>); float lgammaf(float <VAR>x</VAR>); double gamma_r(double <VAR>x</VAR>, int *<VAR>signgamp</VAR>); float gammaf_r(float <VAR>x</VAR>, int *<VAR>signgamp</VAR>); double lgamma_r(double <VAR>x</VAR>, int *<VAR>signgamp</VAR>); float lgammaf_r(float <VAR>x</VAR>, int *<VAR>signgamp</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>gamma</CODE> calculates the natural logarithm of the gamma function of <VAR>x</VAR>. The gamma function (<CODE>exp(gamma(<VAR>x</VAR>))</CODE>) is a generalization of factorial, and retains the property that Accordingly, the results of the gamma function itself grow very quickly. <CODE>gamma</CODE> is defined as to extend the useful range of results representable. <P> The sign of the result is returned in the global variable <CODE>signgam</CODE>, which is declared in math.h. </P><P> <CODE>gammaf</CODE> performs the same calculation as <CODE>gamma</CODE>, but uses and returns <CODE>float</CODE> values. </P><P> <CODE>lgamma</CODE> and <CODE>lgammaf</CODE> are alternate names for <CODE>gamma</CODE> and <CODE>gammaf</CODE>. The use of <CODE>lgamma</CODE> instead of <CODE>gamma</CODE> is a reminder that these functions compute the log of the gamma function, rather than the gamma function itself. </P><P> The functions <CODE>gamma_r</CODE>, <CODE>gammaf_r</CODE>, <CODE>lgamma_r</CODE>, and <CODE>lgammaf_r</CODE> are just like <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, and <CODE>lgammaf</CODE>, respectively, but take an additional argument. This additional argument is a pointer to an integer. This additional argument is used to return the sign of the result, and the global variable <CODE>signgam</CODE> is not used. These functions may be used for reentrant calls (but they will still set the global variable <CODE>errno</CODE> if an error occurs). </P><P> <BR> <STRONG>Returns</STRONG><BR> Normally, the computed result is returned. </P><P> When <VAR>x</VAR> is a nonpositive integer, <CODE>gamma</CODE> returns <CODE>HUGE_VAL</CODE> and <CODE>errno</CODE> is set to <CODE>EDOM</CODE>. If the result overflows, <CODE>gamma</CODE> returns <CODE>HUGE_VAL</CODE> and <CODE>errno</CODE> is set to <CODE>ERANGE</CODE>. </P><P> You can modify this error treatment using <CODE>matherr</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> Neither <CODE>gamma</CODE> nor <CODE>gammaf</CODE> is ANSI C. <BR> </P><P> <A NAME="hypot"></A> <HR SIZE="6"> <A NAME="SEC19"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC18"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC20"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.18 <CODE>hypot</CODE>, <CODE>hypotf</CODE>---distance from origin </H2> <!--docid::SEC19::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double hypot(double <VAR>x</VAR>, double <VAR>y</VAR>); float hypotf(float <VAR>x</VAR>, float <VAR>y</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>hypot</CODE> calculates the Euclidean distance between the origin (0,0) and a point represented by the Cartesian coordinates (<VAR>x</VAR>,<VAR>y</VAR>). <CODE>hypotf</CODE> differs only in the type of its arguments and result. <P> <BR> <STRONG>Returns</STRONG><BR> Normally, the distance value is returned. On overflow, <CODE>hypot</CODE> returns <CODE>HUGE_VAL</CODE> and sets <CODE>errno</CODE> to <CODE>ERANGE</CODE>. </P><P> You can change the error treatment with <CODE>matherr</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>hypot</CODE> and <CODE>hypotf</CODE> are not ANSI C. <BR> </P><P> <A NAME="isnan"></A> <HR SIZE="6"> <A NAME="SEC20"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC19"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC21"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.19 <CODE>isnan</CODE>,<CODE>isnanf</CODE>,<CODE>isinf</CODE>,<CODE>isinff</CODE>,<CODE>finite</CODE>,<CODE>finitef</CODE>---test for exceptional numbers </H2> <!--docid::SEC20::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <ieeefp.h> int isnan(double <VAR>arg</VAR>); int isinf(double <VAR>arg</VAR>); int finite(double <VAR>arg</VAR>); int isnanf(float <VAR>arg</VAR>); int isinff(float <VAR>arg</VAR>); int finitef(float <VAR>arg</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> These functions provide information on the floating point argument supplied. <P> There are five major number formats - <DL COMPACT> <DT><CODE>zero</CODE> <DD>a number which contains all zero bits. <DT><CODE>subnormal</CODE> <DD>Is used to represent number with a zero exponent, but a non zero fraction. <DT><CODE>normal</CODE> <DD>A number with an exponent, and a fraction <DT><CODE>infinity</CODE> <DD>A number with an all 1's exponent and a zero fraction. <DT><CODE>NAN</CODE> <DD>A number with an all 1's exponent and a non zero fraction. <P> </DL> <P> <CODE>isnan</CODE> returns 1 if the argument is a nan. <CODE>isinf</CODE> returns 1 if the argument is infinity. <CODE>finite</CODE> returns 1 if the argument is zero, subnormal or normal. The <CODE>isnanf</CODE>, <CODE>isinff</CODE> and <CODE>finitef</CODE> perform the same operations as their <CODE>isnan</CODE>, <CODE>isinf</CODE> and <CODE>finite</CODE> counterparts, but on single precision floating point numbers. </P><P> <BR> </P><P> <A NAME="ldexp"></A> <HR SIZE="6"> <A NAME="SEC21"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC20"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC22"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.20 <CODE>ldexp</CODE>, <CODE>ldexpf</CODE>---load exponent </H2> <!--docid::SEC21::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double ldexp(double <VAR>val</VAR>, int <VAR>exp</VAR>); float ldexpf(float <VAR>val</VAR>, int <VAR>exp</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>ldexp</CODE> calculates the value <CODE>ldexpf</CODE> is identical, save that it takes and returns <CODE>float</CODE> rather than <CODE>double</CODE> values. <P> <BR> <STRONG>Returns</STRONG><BR> <CODE>ldexp</CODE> returns the calculated value. </P><P> Underflow and overflow both set <CODE>errno</CODE> to <CODE>ERANGE</CODE>. On underflow, <CODE>ldexp</CODE> and <CODE>ldexpf</CODE> return 0.0. On overflow, <CODE>ldexp</CODE> returns plus or minus <CODE>HUGE_VAL</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>ldexp</CODE> is ANSI, <CODE>ldexpf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="log"></A> <HR SIZE="6"> <A NAME="SEC22"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC21"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC23"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.21 <CODE>log</CODE>, <CODE>logf</CODE>---natural logarithms </H2> <!--docid::SEC22::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double log(double <VAR>x</VAR>); float logf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> Return the natural logarithm of <VAR>x</VAR>, that is, its logarithm base e (where e is the base of the natural system of logarithms, 2.71828<small>...</small>). <CODE>log</CODE> and <CODE>logf</CODE> are identical save for the return and argument types. <P> You can use the (non-ANSI) function <CODE>matherr</CODE> to specify error handling for these functions. </P><P> <BR> <STRONG>Returns</STRONG><BR> Normally, returns the calculated value. When <VAR>x</VAR> is zero, the returned value is <CODE>-HUGE_VAL</CODE> and <CODE>errno</CODE> is set to <CODE>ERANGE</CODE>. When <VAR>x</VAR> is negative, the returned value is <CODE>-HUGE_VAL</CODE> and <CODE>errno</CODE> is set to <CODE>EDOM</CODE>. You can control the error behavior via <CODE>matherr</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>log</CODE> is ANSI, <CODE>logf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="log10"></A> <HR SIZE="6"> <A NAME="SEC23"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC22"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC24"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.22 <CODE>log10</CODE>, <CODE>log10f</CODE>---base 10 logarithms </H2> <!--docid::SEC23::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double log10(double <VAR>x</VAR>); float log10f(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>log10</CODE> returns the base 10 logarithm of <VAR>x</VAR>. It is implemented as <CODE>log(<VAR>x</VAR>) / log(10)</CODE>. <P> <CODE>log10f</CODE> is identical, save that it takes and returns <CODE>float</CODE> values. </P><P> <BR> <STRONG>Returns</STRONG><BR> <CODE>log10</CODE> and <CODE>log10f</CODE> return the calculated value. </P><P> See the description of <CODE>log</CODE> for information on errors. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>log10</CODE> is ANSI C. <CODE>log10f</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="pow"></A> <HR SIZE="6"> <A NAME="SEC24"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC23"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC25"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.23 <CODE>pow</CODE>, <CODE>powf</CODE>---x to the power y </H2> <!--docid::SEC24::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double pow(double <VAR>x</VAR>, double <VAR>y</VAR>); float pow(float <VAR>x</VAR>, float <VAR>y</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>pow</CODE> and <CODE>powf</CODE> calculate <VAR>x</VAR> raised to the exp1.0nt <VAR>y</VAR>. <P> <BR> <STRONG>Returns</STRONG><BR> On success, <CODE>pow</CODE> and <CODE>powf</CODE> return the value calculated. </P><P> When the argument values would produce overflow, <CODE>pow</CODE> returns <CODE>HUGE_VAL</CODE> and set <CODE>errno</CODE> to <CODE>ERANGE</CODE>. If the argument <VAR>x</VAR> passed to <CODE>pow</CODE> or <CODE>powf</CODE> is a negative noninteger, and <VAR>y</VAR> is also not an integer, then <CODE>errno</CODE> is set to <CODE>EDOM</CODE>. If <VAR>x</VAR> and <VAR>y</VAR> are both 0, then <CODE>pow</CODE> and <CODE>powf</CODE> return <CODE>1</CODE>. </P><P> You can modify error handling for these functions using <CODE>matherr</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>pow</CODE> is ANSI C. <CODE>powf</CODE> is an extension. <BR> </P><P> <A NAME="remainder"></A> <HR SIZE="6"> <A NAME="SEC25"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC24"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC26"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.24 <CODE>remainder</CODE>, <CODE>remainderf</CODE>---round and remainder </H2> <!--docid::SEC25::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double remainder(double <VAR>x</VAR>, double <VAR>y</VAR>); float remainderf(float <VAR>x</VAR>, float <VAR>y</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>remainder</CODE> and <CODE>remainderf</CODE> find the remainder of <VAR>x</VAR>/<VAR>y</VAR>; this value is in the range -<VAR>y</VAR>/2 .. +<VAR>y</VAR>/2. <P> <BR> <STRONG>Returns</STRONG><BR> <CODE>remainder</CODE> returns the integer result as a double. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>remainder</CODE> is a System V release 4. <CODE>remainderf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="sqrt"></A> <HR SIZE="6"> <A NAME="SEC26"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC25"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC27"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.25 <CODE>sqrt</CODE>, <CODE>sqrtf</CODE>---positive square root </H2> <!--docid::SEC26::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double sqrt(double <VAR>x</VAR>); float sqrtf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>sqrt</CODE> computes the positive square root of the argument. You can modify error handling for this function with <CODE>matherr</CODE>. <P> <BR> <STRONG>Returns</STRONG><BR> On success, the square root is returned. If <VAR>x</VAR> is real and positive, then the result is positive. If <VAR>x</VAR> is real and negative, the global value <CODE>errno</CODE> is set to <CODE>EDOM</CODE> (domain error). </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>sqrt</CODE> is ANSI C. <CODE>sqrtf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="sin"></A> <HR SIZE="6"> <A NAME="SEC27"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC26"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC28"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.26 <CODE>sin</CODE>, <CODE>sinf</CODE>, <CODE>cos</CODE>, <CODE>cosf</CODE>---sine or cosine </H2> <!--docid::SEC27::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double sin(double <VAR>x</VAR>); float sinf(float <VAR>x</VAR>); double cos(double <VAR>x</VAR>); float cosf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>sin</CODE> and <CODE>cos</CODE> compute (respectively) the sine and cosine of the argument <VAR>x</VAR>. Angles are specified in radians. <P> <CODE>sinf</CODE> and <CODE>cosf</CODE> are identical, save that they take and return <CODE>float</CODE> values. </P><P> <BR> <STRONG>Returns</STRONG><BR> The sine or cosine of <VAR>x</VAR> is returned. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>sin</CODE> and <CODE>cos</CODE> are ANSI C. <CODE>sinf</CODE> and <CODE>cosf</CODE> are extensions. </P><P> <BR> </P><P> <A NAME="sinh"></A> <HR SIZE="6"> <A NAME="SEC28"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC27"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC29"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.27 <CODE>sinh</CODE>, <CODE>sinhf</CODE>---hyperbolic sine </H2> <!--docid::SEC28::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double sinh(double <VAR>x</VAR>); float sinhf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>sinh</CODE> computes the hyperbolic sine of the argument <VAR>x</VAR>. Angles are specified in radians. <CODE>sinh</CODE>(<VAR>x</VAR>) is defined as <P> <CODE>sinhf</CODE> is identical, save that it takes and returns <CODE>float</CODE> values. </P><P> <BR> <STRONG>Returns</STRONG><BR> The hyperbolic sine of <VAR>x</VAR> is returned. </P><P> When the correct result is too large to be representable (an overflow), <CODE>sinh</CODE> returns <CODE>HUGE_VAL</CODE> with the appropriate sign, and sets the global value <CODE>errno</CODE> to <CODE>ERANGE</CODE>. </P><P> You can modify error handling for these functions with <CODE>matherr</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>sinh</CODE> is ANSI C. <CODE>sinhf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="tan"></A> <HR SIZE="6"> <A NAME="SEC29"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC28"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC30"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.28 <CODE>tan</CODE>, <CODE>tanf</CODE>---tangent </H2> <!--docid::SEC29::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double tan(double <VAR>x</VAR>); float tanf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>tan</CODE> computes the tangent of the argument <VAR>x</VAR>. Angles are specified in radians. <P> <CODE>tanf</CODE> is identical, save that it takes and returns <CODE>float</CODE> values. </P><P> <BR> <STRONG>Returns</STRONG><BR> The tangent of <VAR>x</VAR> is returned. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>tan</CODE> is ANSI. <CODE>tanf</CODE> is an extension. </P><P> <BR> </P><P> <A NAME="tanh"></A> <HR SIZE="6"> <A NAME="SEC30"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC29"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC31"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.29 <CODE>tanh</CODE>, <CODE>tanhf</CODE>---hyperbolic tangent </H2> <!--docid::SEC30::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double tanh(double <VAR>x</VAR>); float tanhf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <P> <CODE>tanh</CODE> computes the hyperbolic tangent of the argument <VAR>x</VAR>. Angles are specified in radians. </P><P> <CODE>tanh(<VAR>x</VAR>)</CODE> is defined as <TABLE><tr><td> </td><td class=smallexample><FONT SIZE=-1><pre> sinh(<VAR>x</VAR>)/cosh(<VAR>x</VAR>) </FONT></pre></td></tr></table><CODE>tanhf</CODE> is identical, save that it takes and returns <CODE>float</CODE> values. </P><P> <BR> <STRONG>Returns</STRONG><BR> The hyperbolic tangent of <VAR>x</VAR> is returned. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>tanh</CODE> is ANSI C. <CODE>tanhf</CODE> is an extension. </P><P> <BR> <A NAME="cbrt"></A> <HR SIZE="6"> <A NAME="SEC31"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC30"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC32"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.30 <CODE>cbrt</CODE>, <CODE>cbrtf</CODE>---cube root </H2> <!--docid::SEC31::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double cbrt(double <VAR>x</VAR>); float cbrtf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>cbrt</CODE> computes the cube root of the argument. <P> <BR> <STRONG>Returns</STRONG><BR> The cube root is returned. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>cbrt</CODE> is in System V release 4. <CODE>cbrtf</CODE> is an extension. </P><P> <BR> <A NAME="copysign"></A> <HR SIZE="6"> <A NAME="SEC32"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC31"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC33"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.31 <CODE>copysign</CODE>, <CODE>copysignf</CODE>---sign of <VAR>y</VAR>, magnitude of <VAR>x</VAR> </H2> <!--docid::SEC32::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double copysign (double <VAR>x</VAR>, double <VAR>y</VAR>); float copysignf (float <VAR>x</VAR>, float <VAR>y</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>copysign</CODE> constructs a number with the magnitude (absolute value) of its first argument, <VAR>x</VAR>, and the sign of its second argument, <VAR>y</VAR>. <P> <CODE>copysignf</CODE> does the same thing; the two functions differ only in the type of their arguments and result. </P><P> <BR> <STRONG>Returns</STRONG><BR> <CODE>copysign</CODE> returns a <CODE>double</CODE> with the magnitude of <VAR>x</VAR> and the sign of <VAR>y</VAR>. <CODE>copysignf</CODE> returns a <CODE>float</CODE> with the magnitude of <VAR>x</VAR> and the sign of <VAR>y</VAR>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>copysign</CODE> is not required by either ANSI C or the System V Interface Definition (Issue 2). </P><P> <BR> <A NAME="expm1"></A> <HR SIZE="6"> <A NAME="SEC33"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC32"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC34"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.32 <CODE>expm1</CODE>, <CODE>expm1f</CODE>---exponential minus 1 </H2> <!--docid::SEC33::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double expm1(double <VAR>x</VAR>); float expm1f(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>expm1</CODE> and <CODE>expm1f</CODE> calculate the exponential of <VAR>x</VAR> and subtract 1, that is, is the base of the natural system of logarithms, approximately 2.71828). The result is accurate even for small values of <VAR>x</VAR>, where using <CODE>exp(<VAR>x</VAR>)-1</CODE> would lose many significant digits. <P> <BR> <STRONG>Returns</STRONG><BR> e raised to the power <VAR>x</VAR>, minus 1. </P><P> <BR> <STRONG>Portability</STRONG><BR> Neither <CODE>expm1</CODE> nor <CODE>expm1f</CODE> is required by ANSI C or by the System V Interface Definition (Issue 2). </P><P> <BR> <A NAME="ilogb"></A> <HR SIZE="6"> <A NAME="SEC34"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC33"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC35"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.33 <CODE>ilogb</CODE>, <CODE>ilogbf</CODE>---get exponent of floating point number </H2> <!--docid::SEC34::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> int ilogb(double <VAR>val</VAR>); int ilogbf(float <VAR>val</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <P> All non zero, normal numbers can be described as <VAR>m</VAR> * 2**<VAR>p</VAR>. <CODE>ilogb</CODE> and <CODE>ilogbf</CODE> examine the argument <VAR>val</VAR>, and return <VAR>p</VAR>. The functions <CODE>frexp</CODE> and <CODE>frexpf</CODE> are similar to <CODE>ilogb</CODE> and <CODE>ilogbf</CODE>, but also return <VAR>m</VAR>. </P><P> <BR> <STRONG>Returns</STRONG><BR> </P><P> <CODE>ilogb</CODE> and <CODE>ilogbf</CODE> return the power of two used to form the floating point argument. If <VAR>val</VAR> is <CODE>0</CODE>, they return <CODE>- INT_MAX</CODE> (<CODE>INT_MAX</CODE> is defined in limits.h). If <VAR>val</VAR> is infinite, or NaN, they return <CODE>INT_MAX</CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> Neither <CODE>ilogb</CODE> nor <CODE>ilogbf</CODE> is required by ANSI C or by the System V Interface Definition (Issue 2). <BR> <A NAME="infinity"></A> <HR SIZE="6"> <A NAME="SEC35"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC34"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC36"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.34 <CODE>infinity</CODE>, <CODE>infinityf</CODE>---representation of infinity </H2> <!--docid::SEC35::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double infinity(void); float infinityf(void); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>infinity</CODE> and <CODE>infinityf</CODE> return the special number IEEE infinity in double and single precision arithmetic respectivly. <P> <BR> <A NAME="log1p"></A> <HR SIZE="6"> <A NAME="SEC36"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC35"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC37"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.35 <CODE>log1p</CODE>, <CODE>log1pf</CODE>---log of <CODE>1 + <VAR>x</VAR></CODE> </H2> <!--docid::SEC36::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double log1p(double <VAR>x</VAR>); float log1pf(float <VAR>x</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>log1p</CODE> calculates the natural logarithm of <CODE>1+<VAR>x</VAR></CODE>. You can use <CODE>log1p</CODE> rather than `<CODE>log(1+<VAR>x</VAR>)</CODE>' for greater precision when <VAR>x</VAR> is very small. <P> <CODE>log1pf</CODE> calculates the same thing, but accepts and returns <CODE>float</CODE> values rather than <CODE>double</CODE>. </P><P> <BR> <STRONG>Returns</STRONG><BR> <CODE>log1p</CODE> returns a <CODE>double</CODE>, the natural log of <CODE>1+<VAR>x</VAR></CODE>. <CODE>log1pf</CODE> returns a <CODE>float</CODE>, the natural log of <CODE>1+<VAR>x</VAR></CODE>. </P><P> <BR> <STRONG>Portability</STRONG><BR> Neither <CODE>log1p</CODE> nor <CODE>log1pf</CODE> is required by ANSI C or by the System V Interface Definition (Issue 2). </P><P> <BR> <A NAME="matherr"></A> <HR SIZE="6"> <A NAME="SEC37"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC36"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC38"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.36 <CODE>matherr</CODE>---modifiable math error handler </H2> <!--docid::SEC37::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> int matherr(struct exception *<VAR>e</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>matherr</CODE> is called whenever a math library function generates an error. You can replace <CODE>matherr</CODE> by your own subroutine to customize error treatment. The customized <CODE>matherr</CODE> must return 0 if it fails to resolve the error, and non-zero if the error is resolved. <P> When <CODE>matherr</CODE> returns a nonzero value, no error message is printed and the value of <CODE>errno</CODE> is not modified. You can accomplish either or both of these things in your own <CODE>matherr</CODE> using the information passed in the structure <CODE>*<VAR>e</VAR></CODE>. </P><P> This is the <CODE>exception</CODE> structure (defined in `<CODE>math.h</CODE>'): <TABLE><tr><td> </td><td class=smallexample><FONT SIZE=-1><pre>struct exception { int type; char *name; double arg1, arg2, retval; int err; }; </FONT></pre></td></tr></table></P><P> The members of the exception structure have the following meanings: <DL COMPACT> <DT><CODE>type</CODE> <DD>The type of mathematical error that occured; macros encoding error types are also defined in `<CODE>math.h</CODE>'. <P> <DT><CODE>name</CODE> <DD>a pointer to a null-terminated string holding the name of the math library function where the error occurred. <P> <DT><CODE>arg1, arg2</CODE> <DD>The arguments which caused the error. <P> <DT><CODE>retval</CODE> <DD>The error return value (what the calling function will return). <P> <DT><CODE>err</CODE> <DD>If set to be non-zero, this is the new value assigned to <CODE>errno</CODE>. </DL> <P> The error types defined in `<CODE>math.h</CODE>' represent possible mathematical errors as follows: </P><P> <DL COMPACT> <DT><CODE>DOMAIN</CODE> <DD>An argument was not in the domain of the function; e.g. <CODE>log(-1.0)</CODE>. <P> <DT><CODE>SING</CODE> <DD>The requested calculation would result in a singularity; e.g. <CODE>pow(0.0,-2.0)</CODE> <P> <DT><CODE>OVERFLOW</CODE> <DD>A calculation would produce a result too large to represent; e.g. <CODE>exp(1000.0)</CODE>. <P> <DT><CODE>UNDERFLOW</CODE> <DD>A calculation would produce a result too small to represent; e.g. <CODE>exp(-1000.0)</CODE>. <P> <DT><CODE>TLOSS</CODE> <DD>Total loss of precision. The result would have no significant digits; e.g. <CODE>sin(10e70)</CODE>. <P> <DT><CODE>PLOSS</CODE> <DD>Partial loss of precision. </DL> <P> <BR> <STRONG>Returns</STRONG><BR> The library definition for <CODE>matherr</CODE> returns <CODE>0</CODE> in all cases. </P><P> You can change the calling function's result from a customized <CODE>matherr</CODE> by modifying <CODE>e->retval</CODE>, which propagates backs to the caller. </P><P> If <CODE>matherr</CODE> returns <CODE>0</CODE> (indicating that it was not able to resolve the error) the caller sets <CODE>errno</CODE> to an appropriate value, and prints an error message. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>matherr</CODE> is not ANSI C. </P><P> <BR> <A NAME="modf"></A> <HR SIZE="6"> <A NAME="SEC38"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC37"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC39"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.37 <CODE>modf</CODE>, <CODE>modff</CODE>---split fractional and integer parts </H2> <!--docid::SEC38::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double modf(double <VAR>val</VAR>, double *<VAR>ipart</VAR>); float modff(float <VAR>val</VAR>, float *<VAR>ipart</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>modf</CODE> splits the double <VAR>val</VAR> apart into an integer part and a fractional part, returning the fractional part and storing the integer part in <CODE>*<VAR>ipart</VAR></CODE>. No rounding whatsoever is done; the sum of the integer and fractional parts is guaranteed to be exactly equal to <VAR>val</VAR>. That is, if . <VAR>realpart</VAR> = modf(<VAR>val</VAR>, &<VAR>intpart</VAR>); then `<CODE><VAR>realpart</VAR>+<VAR>intpart</VAR></CODE>' is the same as <VAR>val</VAR>. <CODE>modff</CODE> is identical, save that it takes and returns <CODE>float</CODE> rather than <CODE>double</CODE> values. <P> <BR> <STRONG>Returns</STRONG><BR> The fractional part is returned. Each result has the same sign as the supplied argument <VAR>val</VAR>. </P><P> <BR> <STRONG>Portability</STRONG><BR> <CODE>modf</CODE> is ANSI C. <CODE>modff</CODE> is an extension. </P><P> <BR> <A NAME="nan"></A> <HR SIZE="6"> <A NAME="SEC39"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC38"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC40"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.38 <CODE>nan</CODE>, <CODE>nanf</CODE>---representation of infinity </H2> <!--docid::SEC39::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double nan(void); float nanf(void); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>nan</CODE> and <CODE>nanf</CODE> return an IEEE NaN (Not a Number) in double and single precision arithmetic respectivly. <P> <BR> <A NAME="nextafter"></A> <HR SIZE="6"> <A NAME="SEC40"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC39"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC41"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.39 <CODE>nextafter</CODE>, <CODE>nextafterf</CODE>---get next number </H2> <!--docid::SEC40::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double nextafter(double <VAR>val</VAR>, double <VAR>dir</VAR>); float nextafterf(float <VAR>val</VAR>, float <VAR>dir</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>nextafter</CODE> returns the double) precision floating point number closest to <VAR>val</VAR> in the direction toward <VAR>dir</VAR>. <CODE>nextafterf</CODE> performs the same operation in single precision. For example, <CODE>nextafter(0.0,1.0)</CODE> returns the smallest positive number which is representable in double precision. <P> <BR> <STRONG>Returns</STRONG><BR> Returns the next closest number to <VAR>val</VAR> in the direction toward <VAR>dir</VAR>. </P><P> <BR> <STRONG>Portability</STRONG><BR> Neither <CODE>nextafter</CODE> nor <CODE>nextafterf</CODE> is required by ANSI C or by the System V Interface Definition (Issue 2). </P><P> <BR> <A NAME="scalbn"></A> <HR SIZE="6"> <A NAME="SEC41"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC40"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC42"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H2> 1.40 <CODE>scalbn</CODE>, <CODE>scalbnf</CODE>---scale by integer </H2> <!--docid::SEC41::--> <STRONG>Synopsis</STRONG> <TABLE><tr><td> </td><td class=example><pre>#include <math.h> double scalbn(double <VAR>x</VAR>, int <VAR>y</VAR>); float scalbnf(float <VAR>x</VAR>, int <VAR>y</VAR>); </pre></td></tr></table><STRONG>Description</STRONG><BR> <CODE>scalbn</CODE> and <CODE>scalbnf</CODE> scale <VAR>x</VAR> by <VAR>n</VAR>, returning <VAR>x</VAR> times 2 to the power <VAR>n</VAR>. The result is computed by manipulating the exponent, rather than by actually performing an exponentiation or multiplication. <P> <BR> <STRONG>Returns</STRONG><BR> <VAR>x</VAR> times 2 to the power <VAR>n</VAR>. </P><P> <BR> <STRONG>Portability</STRONG><BR> Neither <CODE>scalbn</CODE> nor <CODE>scalbnf</CODE> is required by ANSI C or by the System V Interface Definition (Issue 2). </P><P> <BR> </P><P> <A NAME="Reentrancy"></A> <HR SIZE="6"> <A NAME="SEC42"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC41"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43"> > </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H1> 2. Reentrancy Properties of <CODE>libm</CODE> </H1> <!--docid::SEC42::--> <P> <A NAME="IDX5"></A> <A NAME="IDX6"></A> When a libm function detects an exceptional case, <CODE>errno</CODE> may be set, the <CODE>matherr</CODE> function may be called, and a error message may be written to the standard error stream. This behavior may not be reentrant. </P><P> With reentrant C libraries like the Red Hat newlib C library, <CODE>errno</CODE> is a macro which expands to the per-thread error value. This makes it thread safe. </P><P> When the user provides his own <CODE>matherr</CODE> function it must be reentrant for the math library as a whole to be reentrant. </P><P> In normal debugged programs, there are usually no math subroutine errors--and therefore no assignments to <CODE>errno</CODE> and no <CODE>matherr</CODE> calls; in that situation, the math functions behave reentrantly. </P><P> <A NAME="Index"></A> <HR SIZE="6"> <A NAME="SEC43"></A> <TABLE CELLPADDING=1 CELLSPACING=1 BORDER=0> <TR><TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC42"> < </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ > ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ << ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1"> Up </A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[ >> ]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT"> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC1">Top</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm_toc.html#SEC_Contents">Contents</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC43">Index</A>]</TD> <TD VALIGN="MIDDLE" ALIGN="LEFT">[<A HREF="libm.html#SEC_About"> ? </A>]</TD> </TR></TABLE> <H1> Index </H1> <!--docid::SEC43::--> <table><tr><th valign=top>Jump to: </th><td><A HREF="libm.html#cp_A" style="text-decoration:none"><b>A</b></A> <A HREF="libm.html#cp_C" style="text-decoration:none"><b>C</b></A> <A HREF="libm.html#cp_E" style="text-decoration:none"><b>E</b></A> <A HREF="libm.html#cp_F" style="text-decoration:none"><b>F</b></A> <A HREF="libm.html#cp_G" style="text-decoration:none"><b>G</b></A> <A HREF="libm.html#cp_H" style="text-decoration:none"><b>H</b></A> <A HREF="libm.html#cp_I" style="text-decoration:none"><b>I</b></A> <A HREF="libm.html#cp_J" style="text-decoration:none"><b>J</b></A> <A HREF="libm.html#cp_L" style="text-decoration:none"><b>L</b></A> <A HREF="libm.html#cp_M" style="text-decoration:none"><b>M</b></A> <A HREF="libm.html#cp_N" style="text-decoration:none"><b>N</b></A> <A HREF="libm.html#cp_O" style="text-decoration:none"><b>O</b></A> <A HREF="libm.html#cp_P" style="text-decoration:none"><b>P</b></A> <A HREF="libm.html#cp_R" style="text-decoration:none"><b>R</b></A> <A HREF="libm.html#cp_S" style="text-decoration:none"><b>S</b></A> <A HREF="libm.html#cp_T" style="text-decoration:none"><b>T</b></A> <A HREF="libm.html#cp_Y" style="text-decoration:none"><b>Y</b></A> </td></tr></table><br><P></P> <TABLE border=0> <TR><TD></TD><TH ALIGN=LEFT>Index Entry</TH><TH ALIGN=LEFT> Section</TH></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_A"></A>A</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC3"><CODE>acos</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC3">1.2 <CODE>acos</CODE>, <CODE>acosf</CODE>---arc cosine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC3"><CODE>acosf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC3">1.2 <CODE>acos</CODE>, <CODE>acosf</CODE>---arc cosine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC4"><CODE>acosh</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC4">1.3 <CODE>acosh</CODE>, <CODE>acoshf</CODE>---inverse hyperbolic cosine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC4"><CODE>acoshf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC4">1.3 <CODE>acosh</CODE>, <CODE>acoshf</CODE>---inverse hyperbolic cosine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC5"><CODE>asin</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC5">1.4 <CODE>asin</CODE>, <CODE>asinf</CODE>---arc sine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC5"><CODE>asinf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC5">1.4 <CODE>asin</CODE>, <CODE>asinf</CODE>---arc sine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC6"><CODE>asinh</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC6">1.5 <CODE>asinh</CODE>, <CODE>asinhf</CODE>---inverse hyperbolic sine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC6"><CODE>asinhf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC6">1.5 <CODE>asinh</CODE>, <CODE>asinhf</CODE>---inverse hyperbolic sine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC7"><CODE>atan</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC7">1.6 <CODE>atan</CODE>, <CODE>atanf</CODE>---arc tangent</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC8"><CODE>atan2</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC8">1.7 <CODE>atan2</CODE>, <CODE>atan2f</CODE>---arc tangent of y/x</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC8"><CODE>atan2f</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC8">1.7 <CODE>atan2</CODE>, <CODE>atan2f</CODE>---arc tangent of y/x</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC7"><CODE>atanf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC7">1.6 <CODE>atan</CODE>, <CODE>atanf</CODE>---arc tangent</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC9"><CODE>atanh</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC9">1.8 <CODE>atanh</CODE>, <CODE>atanhf</CODE>---inverse hyperbolic tangent</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC9"><CODE>atanhf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC9">1.8 <CODE>atanh</CODE>, <CODE>atanhf</CODE>---inverse hyperbolic tangent</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_C"></A>C</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC31"><CODE>cbrt</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC31">1.30 <CODE>cbrt</CODE>, <CODE>cbrtf</CODE>---cube root</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC31"><CODE>cbrtf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC31">1.30 <CODE>cbrt</CODE>, <CODE>cbrtf</CODE>---cube root</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC15"><CODE>ceil</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC15">1.14 <CODE>floor</CODE>, <CODE>floorf</CODE>, <CODE>ceil</CODE>, <CODE>ceilf</CODE>---floor and ceiling</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC15"><CODE>ceilf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC15">1.14 <CODE>floor</CODE>, <CODE>floorf</CODE>, <CODE>ceil</CODE>, <CODE>ceilf</CODE>---floor and ceiling</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC32"><CODE>copysign</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC32">1.31 <CODE>copysign</CODE>, <CODE>copysignf</CODE>---sign of <VAR>y</VAR>, magnitude of <VAR>x</VAR></A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC32"><CODE>copysignf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC32">1.31 <CODE>copysign</CODE>, <CODE>copysignf</CODE>---sign of <VAR>y</VAR>, magnitude of <VAR>x</VAR></A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC27"><CODE>cos</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC27">1.26 <CODE>sin</CODE>, <CODE>sinf</CODE>, <CODE>cos</CODE>, <CODE>cosf</CODE>---sine or cosine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC27"><CODE>cosf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC27">1.26 <CODE>sin</CODE>, <CODE>sinf</CODE>, <CODE>cos</CODE>, <CODE>cosf</CODE>---sine or cosine</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_E"></A>E</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC12"><CODE>erf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC12">1.11 <CODE>erf</CODE>, <CODE>erff</CODE>, <CODE>erfc</CODE>, <CODE>erfcf</CODE>---error function</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC12"><CODE>erfc</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC12">1.11 <CODE>erf</CODE>, <CODE>erff</CODE>, <CODE>erfc</CODE>, <CODE>erfcf</CODE>---error function</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC12"><CODE>erfcf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC12">1.11 <CODE>erf</CODE>, <CODE>erff</CODE>, <CODE>erfc</CODE>, <CODE>erfcf</CODE>---error function</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC12"><CODE>erff</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC12">1.11 <CODE>erf</CODE>, <CODE>erff</CODE>, <CODE>erfc</CODE>, <CODE>erfcf</CODE>---error function</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC13"><CODE>exp</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC13">1.12 <CODE>exp</CODE>, <CODE>expf</CODE>---exponential</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC13"><CODE>expf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC13">1.12 <CODE>exp</CODE>, <CODE>expf</CODE>---exponential</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC33"><CODE>expm1</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC33">1.32 <CODE>expm1</CODE>, <CODE>expm1f</CODE>---exponential minus 1</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC33"><CODE>expm1f</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC33">1.32 <CODE>expm1</CODE>, <CODE>expm1f</CODE>---exponential minus 1</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_F"></A>F</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC14"><CODE>fabs</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC14">1.13 <CODE>fabs</CODE>, <CODE>fabsf</CODE>---absolute value (magnitude)</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC14"><CODE>fabsf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC14">1.13 <CODE>fabs</CODE>, <CODE>fabsf</CODE>---absolute value (magnitude)</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC20"><CODE>finite</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC20">1.19 <CODE>isnan</CODE>,<CODE>isnanf</CODE>,<CODE>isinf</CODE>,<CODE>isinff</CODE>,<CODE>finite</CODE>,<CODE>finitef</CODE>---test for exceptional numbers</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC20"><CODE>finitef</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC20">1.19 <CODE>isnan</CODE>,<CODE>isnanf</CODE>,<CODE>isinf</CODE>,<CODE>isinff</CODE>,<CODE>finite</CODE>,<CODE>finitef</CODE>---test for exceptional numbers</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC15"><CODE>floor</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC15">1.14 <CODE>floor</CODE>, <CODE>floorf</CODE>, <CODE>ceil</CODE>, <CODE>ceilf</CODE>---floor and ceiling</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC15"><CODE>floorf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC15">1.14 <CODE>floor</CODE>, <CODE>floorf</CODE>, <CODE>ceil</CODE>, <CODE>ceilf</CODE>---floor and ceiling</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC16"><CODE>fmod</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC16">1.15 <CODE>fmod</CODE>, <CODE>fmodf</CODE>---floating-point remainder (modulo)</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC16"><CODE>fmodf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC16">1.15 <CODE>fmod</CODE>, <CODE>fmodf</CODE>---floating-point remainder (modulo)</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC17"><CODE>frexp</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC17">1.16 <CODE>frexp</CODE>, <CODE>frexpf</CODE>---split floating-point number</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC17"><CODE>frexpf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC17">1.16 <CODE>frexp</CODE>, <CODE>frexpf</CODE>---split floating-point number</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_G"></A>G</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC18"><CODE>gamma</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC18">1.17 <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, <CODE>lgammaf</CODE>, <CODE>gamma_r</CODE>,</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC18"><CODE>gamma_r</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC18">1.17 <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, <CODE>lgammaf</CODE>, <CODE>gamma_r</CODE>,</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC18"><CODE>gammaf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC18">1.17 <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, <CODE>lgammaf</CODE>, <CODE>gamma_r</CODE>,</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC18"><CODE>gammaf_r</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC18">1.17 <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, <CODE>lgammaf</CODE>, <CODE>gamma_r</CODE>,</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_H"></A>H</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC19"><CODE>hypot</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC19">1.18 <CODE>hypot</CODE>, <CODE>hypotf</CODE>---distance from origin</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC19"><CODE>hypotf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC19">1.18 <CODE>hypot</CODE>, <CODE>hypotf</CODE>---distance from origin</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_I"></A>I</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC34"><CODE>ilogb</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC34">1.33 <CODE>ilogb</CODE>, <CODE>ilogbf</CODE>---get exponent of floating point number</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC34"><CODE>ilogbf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC34">1.33 <CODE>ilogb</CODE>, <CODE>ilogbf</CODE>---get exponent of floating point number</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC35"><CODE>infinity</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC35">1.34 <CODE>infinity</CODE>, <CODE>infinityf</CODE>---representation of infinity</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC35"><CODE>infinityf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC35">1.34 <CODE>infinity</CODE>, <CODE>infinityf</CODE>---representation of infinity</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC20"><CODE>isinf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC20">1.19 <CODE>isnan</CODE>,<CODE>isnanf</CODE>,<CODE>isinf</CODE>,<CODE>isinff</CODE>,<CODE>finite</CODE>,<CODE>finitef</CODE>---test for exceptional numbers</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC20"><CODE>isinff</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC20">1.19 <CODE>isnan</CODE>,<CODE>isnanf</CODE>,<CODE>isinf</CODE>,<CODE>isinff</CODE>,<CODE>finite</CODE>,<CODE>finitef</CODE>---test for exceptional numbers</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC20"><CODE>isnan</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC20">1.19 <CODE>isnan</CODE>,<CODE>isnanf</CODE>,<CODE>isinf</CODE>,<CODE>isinff</CODE>,<CODE>finite</CODE>,<CODE>finitef</CODE>---test for exceptional numbers</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC20"><CODE>isnanf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC20">1.19 <CODE>isnan</CODE>,<CODE>isnanf</CODE>,<CODE>isinf</CODE>,<CODE>isinff</CODE>,<CODE>finite</CODE>,<CODE>finitef</CODE>---test for exceptional numbers</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_J"></A>J</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>j0</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>j0f</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>j1</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>j1f</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>jn</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>jnf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_L"></A>L</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC21"><CODE>ldexp</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC21">1.20 <CODE>ldexp</CODE>, <CODE>ldexpf</CODE>---load exponent</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC21"><CODE>ldexpf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC21">1.20 <CODE>ldexp</CODE>, <CODE>ldexpf</CODE>---load exponent</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC18"><CODE>lgamma</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC18">1.17 <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, <CODE>lgammaf</CODE>, <CODE>gamma_r</CODE>,</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC18"><CODE>lgamma_r</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC18">1.17 <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, <CODE>lgammaf</CODE>, <CODE>gamma_r</CODE>,</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC18"><CODE>lgammaf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC18">1.17 <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, <CODE>lgammaf</CODE>, <CODE>gamma_r</CODE>,</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC18"><CODE>lgammaf_r</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC18">1.17 <CODE>gamma</CODE>, <CODE>gammaf</CODE>, <CODE>lgamma</CODE>, <CODE>lgammaf</CODE>, <CODE>gamma_r</CODE>,</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC22"><CODE>log</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC22">1.21 <CODE>log</CODE>, <CODE>logf</CODE>---natural logarithms</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC23"><CODE>log10</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC23">1.22 <CODE>log10</CODE>, <CODE>log10f</CODE>---base 10 logarithms</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC23"><CODE>log10f</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC23">1.22 <CODE>log10</CODE>, <CODE>log10f</CODE>---base 10 logarithms</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC36"><CODE>log1p</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC36">1.35 <CODE>log1p</CODE>, <CODE>log1pf</CODE>---log of <CODE>1 + <VAR>x</VAR></CODE></A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC36"><CODE>log1pf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC36">1.35 <CODE>log1p</CODE>, <CODE>log1pf</CODE>---log of <CODE>1 + <VAR>x</VAR></CODE></A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC22"><CODE>logf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC22">1.21 <CODE>log</CODE>, <CODE>logf</CODE>---natural logarithms</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_M"></A>M</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC37"><CODE>matherr</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC37">1.36 <CODE>matherr</CODE>---modifiable math error handler</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#IDX6"><CODE>matherr</CODE> and reentrancy</A></TD><TD valign=top><A HREF="libm.html#SEC42">2. Reentrancy Properties of <CODE>libm</CODE></A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC38"><CODE>modf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC38">1.37 <CODE>modf</CODE>, <CODE>modff</CODE>---split fractional and integer parts</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC38"><CODE>modff</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC38">1.37 <CODE>modf</CODE>, <CODE>modff</CODE>---split fractional and integer parts</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_N"></A>N</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC39"><CODE>nan</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC39">1.38 <CODE>nan</CODE>, <CODE>nanf</CODE>---representation of infinity</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC39"><CODE>nanf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC39">1.38 <CODE>nan</CODE>, <CODE>nanf</CODE>---representation of infinity</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC40"><CODE>nextafter</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC40">1.39 <CODE>nextafter</CODE>, <CODE>nextafterf</CODE>---get next number</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC40"><CODE>nextafterf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC40">1.39 <CODE>nextafter</CODE>, <CODE>nextafterf</CODE>---get next number</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_O"></A>O</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#IDX4">OS stubs</A></TD><TD valign=top><A HREF="libm.html#SEC1">1. Mathematical Functions (<TT>`math.h'</TT>)</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_P"></A>P</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC24"><CODE>pow</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC24">1.23 <CODE>pow</CODE>, <CODE>powf</CODE>---x to the power y</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC24"><CODE>powf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC24">1.23 <CODE>pow</CODE>, <CODE>powf</CODE>---x to the power y</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_R"></A>R</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#IDX5">reentrancy</A></TD><TD valign=top><A HREF="libm.html#SEC42">2. Reentrancy Properties of <CODE>libm</CODE></A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC25"><CODE>remainder</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC25">1.24 <CODE>remainder</CODE>, <CODE>remainderf</CODE>---round and remainder</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC25"><CODE>remainderf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC25">1.24 <CODE>remainder</CODE>, <CODE>remainderf</CODE>---round and remainder</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_S"></A>S</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC41"><CODE>scalbn</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC41">1.40 <CODE>scalbn</CODE>, <CODE>scalbnf</CODE>---scale by integer</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC41"><CODE>scalbnf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC41">1.40 <CODE>scalbn</CODE>, <CODE>scalbnf</CODE>---scale by integer</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC27"><CODE>sin</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC27">1.26 <CODE>sin</CODE>, <CODE>sinf</CODE>, <CODE>cos</CODE>, <CODE>cosf</CODE>---sine or cosine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC27"><CODE>sinf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC27">1.26 <CODE>sin</CODE>, <CODE>sinf</CODE>, <CODE>cos</CODE>, <CODE>cosf</CODE>---sine or cosine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC28"><CODE>sinh</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC28">1.27 <CODE>sinh</CODE>, <CODE>sinhf</CODE>---hyperbolic sine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC28"><CODE>sinhf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC28">1.27 <CODE>sinh</CODE>, <CODE>sinhf</CODE>---hyperbolic sine</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC26"><CODE>sqrt</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC26">1.25 <CODE>sqrt</CODE>, <CODE>sqrtf</CODE>---positive square root</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC26"><CODE>sqrtf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC26">1.25 <CODE>sqrt</CODE>, <CODE>sqrtf</CODE>---positive square root</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#IDX3">stubs</A></TD><TD valign=top><A HREF="libm.html#SEC1">1. Mathematical Functions (<TT>`math.h'</TT>)</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#IDX2">support subroutines</A></TD><TD valign=top><A HREF="libm.html#SEC1">1. Mathematical Functions (<TT>`math.h'</TT>)</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#IDX1">system calls</A></TD><TD valign=top><A HREF="libm.html#SEC1">1. Mathematical Functions (<TT>`math.h'</TT>)</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_T"></A>T</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC29"><CODE>tan</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC29">1.28 <CODE>tan</CODE>, <CODE>tanf</CODE>---tangent</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC29"><CODE>tanf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC29">1.28 <CODE>tan</CODE>, <CODE>tanf</CODE>---tangent</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC30"><CODE>tanh</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC30">1.29 <CODE>tanh</CODE>, <CODE>tanhf</CODE>---hyperbolic tangent</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC30"><CODE>tanhf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC30">1.29 <CODE>tanh</CODE>, <CODE>tanhf</CODE>---hyperbolic tangent</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> <TR><TH><A NAME="cp_Y"></A>Y</TH><TD></TD><TD></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>y0</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>y0f</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>y1</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>y1f</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>yn</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD></TD><TD valign=top><A HREF="libm.html#SEC10"><CODE>ynf</CODE></A></TD><TD valign=top><A HREF="libm.html#SEC10">1.9 <CODE>jN</CODE>,<CODE>jNf</CODE>,<CODE>yN</CODE>,<CODE>yNf</CODE>---Bessel functions</A></TD></TR> <TR><TD COLSPAN=3> <HR></TD></TR> </TABLE><P></P><table><tr><th valign=top>Jump to: </th><td><A HREF="libm.html#cp_A" style="text-decoration:none"><b>A</b></A> <A HREF="libm.html#cp_C" style="text-decoration:none"><b>C</b></A> <A HREF="libm.html#cp_E" style="text-decoration:none"><b>E</b></A> <A HREF="libm.html#cp_F" style="text-decoration:none"><b>F</b></A> <A HREF="libm.html#cp_G" style="text-decoration:none"><b>G</b></A> <A HREF="libm.html#cp_H" style="text-decoration:none"><b>H</b></A> <A HREF="libm.html#cp_I" style="text-decoration:none"><b>I</b></A> <A HREF="libm.html#cp_J" style="text-decoration:none"><b>J</b></A> <A HREF="libm.html#cp_L" style="text-decoration:none"><b>L</b></A> <A HREF="libm.html#cp_M" style="text-decoration:none"><b>M</b></A> <A HREF="libm.html#cp_N" style="text-decoration:none"><b>N</b></A> <A HREF="libm.html#cp_O" style="text-decoration:none"><b>O</b></A> <A HREF="libm.html#cp_P" style="text-decoration:none"><b>P</b></A> <A HREF="libm.html#cp_R" style="text-decoration:none"><b>R</b></A> <A HREF="libm.html#cp_S" style="text-decoration:none"><b>S</b></A> <A HREF="libm.html#cp_T" style="text-decoration:none"><b>T</b></A> <A HREF="libm.html#cp_Y" style="text-decoration:none"><b>Y</b></A> </td></tr></table><br><P> <HR SIZE="6">
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