C++

Reference

<cmath> (math.h)

function
<cmath> <ctgmath>

cos

double cos (double x);
 double cos (double x); float cosf (float x);long double cosl (long double x);
 double cos (double x); float cos (float x);long double cos (long double x);
 double cos (double x); float cos (float x);long double cos (long double x); double cos (T x); // additional overloads for integral types
Compute cosine
Returns the cosine of an angle of x radians.

Header <tgmath.h> provides a type-generic macro version of this function.
This function is overloaded in <complex> and <valarray> (see complex cos and valarray cos).
Additional overloads are provided in this header (<cmath>) for the integral types: These overloads effectively cast x to a double before calculations (defined for T being any integral type).

This function is also overloaded in <complex> and <valarray> (see complex cos and valarray cos).

Parameters

x
Value representing an angle expressed in radians.
One radian is equivalent to 180/PI degrees.

Return Value

Cosine of x radians.

Example

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/* cos example */ #include <stdio.h> /* printf */ #include <math.h> /* cos */ #define PI 3.14159265 int main () { double param, result; param = 60.0; result = cos ( param * PI / 180.0 ); printf ("The cosine of %f degrees is %f.\n", param, result ); return 0; }

Output:
 The cosine of 60.000000 degrees is 0.500000.


See also

sin
Compute sine (function)
tan
Compute tangent (function)