Uint8ClampedArray

Usage

var Uint8ClampedArray = require( '@stdlib/array/uint8c' ); 

Uint8ClampedArray()

A typed array constructor which returns a typed array representing an array of 8-bit unsigned integers in the platform byte order clamped to 0-255.

var arr = new Uint8ClampedArray(); // returns <Uint8ClampedArray> 

Uint8ClampedArray( length )

Returns a typed array having a specified length.

var arr = new Uint8ClampedArray( 5 ); // returns <Uint8ClampedArray>[ 0, 0, 0, 0, 0 ] 

Uint8ClampedArray( typedarray )

Creates a typed array from another typed array.

var Float32Array = require( '@stdlib/array/float32' ); var arr1 = new Float32Array( [ 5.0, 5.0, 5.0 ] ); var arr2 = new Uint8ClampedArray( arr1 ); // returns <Uint8ClampedArray>[ 5, 5, 5 ] 

Uint8ClampedArray( obj )

Creates a typed array from an array-like object or iterable.

var arr = new Uint8ClampedArray( [ 5.0, 5.0, 5.0 ] ); // returns <Uint8ClampedArray>[ 5, 5, 5 ] 

Uint8ClampedArray( buffer[, byteOffset[, length]] )

Returns a typed array view of an ArrayBuffer.

var ArrayBuffer = require( '@stdlib/array/buffer' ); var buf = new ArrayBuffer( 4 ); var arr = new Uint8ClampedArray( buf, 0, 4 ); // returns <Uint8ClampedArray>[ 0, 0, 0, 0 ] 

Properties

Uint8ClampedArray.BYTES_PER_ELEMENT

Number of bytes per view element.

var nbytes = Uint8ClampedArray.BYTES_PER_ELEMENT; // returns 1 

Uint8ClampedArray.name

Typed array constructor name.

var str = Uint8ClampedArray.name; // returns 'Uint8ClampedArray' 

Uint8ClampedArray.prototype.buffer

Read-only property which returns the ArrayBuffer referenced by the typed array.

var arr = new Uint8ClampedArray( 5 ); var buf = arr.buffer; // returns <ArrayBuffer> 

Uint8ClampedArray.prototype.byteLength

Read-only property which returns the length (in bytes) of the typed array.

var arr = new Uint8ClampedArray( 5 ); var byteLength = arr.byteLength; // returns 5 

Uint8ClampedArray.prototype.byteOffset

Read-only property which returns the offset (in bytes) of the typed array from the start of its ArrayBuffer.

var arr = new Uint8ClampedArray( 5 ); var byteOffset = arr.byteOffset; // returns 0 

Uint8ClampedArray.prototype.BYTES_PER_ELEMENT

Number of bytes per view element.

var arr = new Uint8ClampedArray( 5 ); var nbytes = arr.BYTES_PER_ELEMENT; // returns 1 

Uint8ClampedArray.prototype.length

Read-only property which returns the number of view elements.

var arr = new Uint8ClampedArray( 5 ); var len = arr.length; // returns 5 

Methods

Uint8ClampedArray.from( src[, map[, thisArg]] )

Creates a new typed array from an array-like object or an iterable.

var arr = Uint8ClampedArray.from( [ 1, 2 ] ); // returns <Uint8ClampedArray>[ 1, 2 ] 

To invoke a function for each src value, provide a callback function.

function mapFcn( v ) { return v * 2; } var arr = Uint8ClampedArray.from( [ 1, 2 ], mapFcn ); // returns <Uint8ClampedArray>[ 2, 4 ] 

A callback function is provided two arguments:

• value: source value.
• index: source index.

To set the callback execution context, provide a thisArg.

function mapFcn( v ) { this.count += 1; return v * 2; } var ctx = { 'count': 0 }; var arr = Uint8ClampedArray.from( [ 1, 2 ], mapFcn, ctx ); // returns <Uint8ClampedArray>[ 2, 4 ] var n = ctx.count; // returns 2 

Uint8ClampedArray.of( element0[, element1[, ...elementN]] )

Creates a new typed array from a variable number of arguments.

var arr = Uint8ClampedArray.of( 1, 2 ); // returns <Uint8ClampedArray>[ 1, 2 ] 

Uint8ClampedArray.prototype.copyWithin( target, start[, end] )

Copies a sequence of elements within an array starting at start and ending at end (non-inclusive) to the position starting at target.

var arr = new Uint8ClampedArray( [ 1, 2, 3, 4, 5 ] ); // Copy the last two elements to the first two elements: arr.copyWithin( 0, 3 ); var v = arr[ 0 ]; // returns 4 v = arr[ 1 ]; // returns 5 

By default, end equals the number of array elements (i.e., one more than the last array index). To limit the sequence length, provide an end argument.

var arr = new Uint8ClampedArray( [ 1, 2, 3, 4, 5 ] ); // Copy the first two elements to the last two elements: arr.copyWithin( 3, 0, 2 ); var v = arr[ 3 ]; // returns 1 v = arr[ 4 ]; // returns 2 

When a target, start, and/or end index is negative, the respective index is determined relative to the last array element. The following example achieves the same behavior as the previous example:

var arr = new Uint8ClampedArray( [ 1, 2, 3, 4, 5 ] ); // Copy the first two elements to the last two elements: arr.copyWithin( -2, -5, -3 ); var v = arr[ 3 ]; // returns 1 v = arr[ 4 ]; // returns 2 

Uint8ClampedArray.prototype.entries()

Returns an iterator for iterating over array key-value pairs.

var arr = new Uint8ClampedArray( [ 1, 2 ] ); // Create an iterator: var it = arr.entries(); // Iterate over key-value pairs... var v = it.next().value; // returns [ 0, 1 ] v = it.next().value; // returns [ 1, 2 ] var bool = it.next().done; // returns true 

Uint8ClampedArray.prototype.every( predicate[, thisArg] )

Tests whether all array elements pass a test implemented by a predicate function.

function predicate( v ) { return ( v <= 1 ); } var arr = new Uint8ClampedArray( [ 1, 2 ] ); var bool = arr.every( predicate ); // returns false 

A predicate function is provided three arguments:

• value: array element.
• index: array index.
• arr: array on which the method is invoked.

To set the callback execution context, provide a thisArg.

function predicate( v ) { this.count += 1; return ( v >= 1 ); } var ctx = { 'count': 0 }; var arr = new Uint8ClampedArray( [ 1, 2 ] ); var bool = arr.every( predicate, ctx ); // returns true var n = ctx.count; // returns 2 

Uint8ClampedArray.prototype.fill( value[, start[, end]] )

Fills an array from a start index to an end index (non-inclusive) with a provided value.

var arr = new Uint8ClampedArray( 2 ); // Set all array elements to the same value: arr.fill( 2 ); var v = arr[ 0 ]; // returns 2 v = arr[ 1 ]; // returns 2 // Set all array elements starting from the first index to the same value: arr.fill( 3, 1 ); v = arr[ 0 ]; // returns 2 v = arr[ 1 ]; // returns 3 // Set all array elements, except the last element, to the same value: arr.fill( 4, 0, arr.length-1 ); v = arr[ 0 ]; // returns 4 v = arr[ 1 ]; // returns 3 

When a start and/or end index is negative, the respective index is determined relative to the last array element.

var arr = new Uint8ClampedArray( 2 ); // Set all array elements, except the last element, to the same value: arr.fill( 2, -arr.length, -1 ); var v = arr[ 0 ]; // returns 2 v = arr[ 1 ]; // returns 0 

Uint8ClampedArray.prototype.filter( predicate[, thisArg] )

Creates a new array (of the same data type as the host array) which includes those elements for which a predicate function returns a truthy value.

function predicate( v ) { return ( v >= 2 ); } var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.filter( predicate ); // returns <Uint8ClampedArray>[ 2, 3 ] 

If a predicate function does not return a truthy value for any array element, the method returns an empty array.

function predicate( v ) { return ( v >= 10 ); } var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.filter( predicate ); // returns <Uint8ClampedArray>[] 

A predicate function is provided three arguments:

• value: array element.
• index: array index.
• arr: array on which the method is invoked.

To set the callback execution context, provide a thisArg.

function predicate( v ) { this.count += 1; return ( v >= 2 ); } var ctx = { 'count': 0 }; var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.filter( predicate, ctx ); var n = ctx.count; // returns 3 

Uint8ClampedArray.prototype.find( predicate[, thisArg] )

Returns the first array element for which a provided predicate function returns a truthy value.

function predicate( v ) { return ( v > 2 ); } var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var v = arr.find( predicate ); // returns 3 

If a predicate function does not return a truthy value for any array element, the method returns undefined.

function predicate( v ) { return ( v < 1 ); } var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var v = arr.find( predicate ); // returns undefined 

A predicate function is provided three arguments:

• value: array element.
• index: array index.
• arr: array on which the method is invoked.

To set the callback execution context, provide a thisArg.

function predicate( v ) { this.count += 1; return ( v > 2 ); } var ctx = { 'count': 0 }; var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var v = arr.find( predicate, ctx ); // returns 3 var n = ctx.count; // returns 3 

Uint8ClampedArray.prototype.findIndex( predicate[, thisArg] )

Returns the index of the first array element for which a provided predicate function returns a truthy value.

function predicate( v ) { return ( v >= 3 ); } var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var idx = arr.findIndex( predicate ); // returns 2 

If a predicate function does not return a truthy value for any array element, the method returns -1.

function predicate( v ) { return ( v < 1 ); } var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var idx = arr.findIndex( predicate ); // returns -1 

A predicate function is provided three arguments:

• value: array element.
• index: array index.
• arr: array on which the method is invoked.

To set the callback execution context, provide a thisArg.

function predicate( v ) { this.count += 1; return ( v >= 3 ); } var ctx = { 'count': 0 }; var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var idx = arr.findIndex( predicate, ctx ); // returns 2 var n = ctx.count; // returns 3 

Uint8ClampedArray.prototype.forEach( fcn[, thisArg] )

Invokes a callback for each array element.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var str = ''; function fcn( v, i ) { str += i + ':' + v; if ( i < arr.length-1 ) { str += ' '; } } arr.forEach( fcn ); console.log( str ); // => '0:1 1:2 2:3' 

The callback is provided three arguments:

• value: array element.
• index: array index.
• arr: array on which the method is invoked.

To set the callback execution context, provide a thisArg.

function fcn() { this.count += 1; } var ctx = { 'count': 0 }; var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); arr.forEach( fcn, ctx ); var n = ctx.count; // returns 3 

Uint8ClampedArray.prototype.includes( searchElement[, fromIndex] )

Returns a boolean indicating whether an array includes a search element.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var bool = arr.includes( 3 ); // returns true bool = arr.includes( 0 ); // returns false 

By default, the method searches the entire array (fromIndex = 0). To begin searching from a specific array index, provide a fromIndex.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var bool = arr.includes( 1, 1 ); // returns false 

When a fromIndex is negative, the starting index is resolved relative to the last array element.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var bool = arr.includes( 1, -2 ); // returns false 

Uint8ClampedArray.prototype.indexOf( searchElement[, fromIndex] )

Returns the index of the first array element strictly equal to a search element.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var idx = arr.indexOf( 3 ); // returns 2 idx = arr.indexOf( 0 ); // returns -1 

By default, the method searches the entire array (fromIndex = 0). To begin searching from a specific array index, provide a fromIndex.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var idx = arr.indexOf( 1, 1 ); // returns -1 

When a fromIndex is negative, the starting index is resolved relative to the last array element.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var idx = arr.indexOf( 1, -2 ); // returns -1 

Uint8ClampedArray.prototype.join( [separator] )

Serializes an array by joining all array elements as a string.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var str = arr.join(); // returns '1,2,3' 

By default, the method delineates array elements using a comma ,. To specify a custom separator, provide a separator string.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var str = arr.join( '|' ); // returns '1|2|3' 

Uint8ClampedArray.prototype.keys()

Returns an iterator for iterating over array keys.

var arr = new Uint8ClampedArray( [ 1, 2 ] ); // Create an iterator: var it = arr.keys(); // Iterate over keys... var v = it.next().value; // returns 0 v = it.next().value; // returns 1 var bool = it.next().done; // returns true 

Uint8ClampedArray.prototype.lastIndexOf( searchElement[, fromIndex] )

Returns the index of the last array element strictly equal to a search element, iterating from right to left.

var arr = new Uint8ClampedArray( [ 1, 0, 2, 0, 1 ] ); var idx = arr.lastIndexOf( 0 ); // returns 3 idx = arr.lastIndexOf( 3 ); // returns -1 

By default, the method searches the entire array (fromIndex = -1). To begin searching from a specific array index, provide a fromIndex.

var arr = new Uint8ClampedArray( [ 1, 0, 2, 0, 1 ] ); var idx = arr.lastIndexOf( 0, 2 ); // returns 1 

When a fromIndex is negative, the starting index is resolved relative to the last array element.

var arr = new Uint8ClampedArray( [ 1, 0, 2, 0, 1 ] ); var idx = arr.lastIndexOf( 0, -3 ); // returns 1 

Uint8ClampedArray.prototype.map( fcn[, thisArg] )

Maps each array element to an element in a new array having the same data type as the host array.

function fcn( v ) { return v * 2; } var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.map( fcn ); // returns <Uint8ClampedArray>[ 2, 4, 6 ] 

A callback is provided three arguments:

• value: array element.
• index: array index.
• arr: array on which the method is invoked.

To set the callback execution context, provide a thisArg.

function fcn( v ) { this.count += 1; return v * 2; } var ctx = { 'count': 0 }; var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.map( fcn, ctx ); var n = ctx.count; // returns 3 

Uint8ClampedArray.prototype.reduce( fcn[, initialValue] )

Applies a function against an accumulator and each element in an array and returns the accumulated result.

function fcn( acc, v ) { return acc + ( v*v ); } var arr = new Uint8ClampedArray( [ 2, 1, 3 ] ); var v = arr.reduce( fcn ); // returns 12 

If not provided an initial value, the method invokes a provided function with the first array element as the first argument and the second array element as the second argument.

If provided an initial value, the method invokes a provided function with the initial value as the first argument and the first array element as the second argument.

function fcn( acc, v ) { return acc + ( v*v ); } var arr = new Uint8ClampedArray( [ 2, 1, 3 ] ); var v = arr.reduce( fcn, 0 ); // returns 14 

A callback is provided four arguments:

• acc: accumulated result.
• value: array element.
• index: array index.
• arr: array on which the method is invoked.

Uint8ClampedArray.prototype.reduceRight( fcn[, initialValue] )

Applies a function against an accumulator and each element in an array and returns the accumulated result, iterating from right to left.

function fcn( acc, v ) { return acc + ( v*v ); } var arr = new Uint8ClampedArray( [ 2, 1, 3 ] ); var v = arr.reduceRight( fcn ); // returns 8 

If not provided an initial value, the method invokes a provided function with the last array element as the first argument and the second-to-last array element as the second argument.

If provided an initial value, the method invokes a provided function with the initial value as the first argument and the last array element as the second argument.

function fcn( acc, v ) { return acc + ( v*v ); } var arr = new Uint8ClampedArray( [ 2, 1, 3 ] ); var v = arr.reduce( fcn, 0 ); // returns 14 

A callback is provided four arguments:

• acc: accumulated result.
• value: array element.
• index: array index.
• arr: array on which the method is invoked.

Uint8ClampedArray.prototype.reverse()

Reverses an array in-place (thus mutating the array on which the method is invoked).

var arr = new Uint8ClampedArray( [ 2, 0, 3 ] ); // Reverse the array: arr.reverse(); var v = arr[ 0 ]; // returns 3 v = arr[ 1 ]; // returns 0 v = arr[ 2 ]; // returns 2 

Uint8ClampedArray.prototype.set( arr[, offset] )

Sets array elements.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); // returns <Uint8ClampedArray>[ 1, 2, 3 ] // Set the first two array elements: arr.set( [ 4, 5 ] ); var v = arr[ 0 ]; // returns 4 v = arr[ 1 ]; // returns 5 

By default, the method starts writing values at the first array index. To specify an alternative index, provide an index offset.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); // returns <Uint8ClampedArray>[ 1, 2, 3 ] // Set the last two array elements: arr.set( [ 4, 5 ], 1 ); var v = arr[ 1 ]; // returns 4 v = arr[ 2 ]; // returns 5 

Uint8ClampedArray.prototype.slice( [begin[, end]] )

Copies array elements to a new array with the same underlying data type as the host array.

var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.slice(); var bool = ( arr1 === arr2 ); // returns false bool = ( arr1.buffer === arr2.buffer ); // returns false var v = arr2[ 0 ]; // returns 1 v = arr2[ 1 ]; // returns 2 v = arr2[ 2 ]; // returns 3 

By default, the method copies elements beginning with the first array element. To specify an alternative array index at which to begin copying, provide a begin index (inclusive).

var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.slice( 1 ); var len = arr2.length; // returns 2 var v = arr2[ 0 ]; // returns 2 v = arr2[ 1 ]; // returns 3 

By default, the method copies all array elements after begin. To specify an alternative array index at which to end copying, provide an end index (exclusive).

var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.slice( 0, 2 ); var len = arr2.length; // returns 2 var v = arr2[ 0 ]; // returns 1 v = arr2[ 1 ]; // returns 2 

When a begin and/or end index is negative, the respective index is determined relative to the last array element.

var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.slice( -arr1.length, -1 ); var len = arr2.length; // returns 2 var v = arr2[ 0 ]; // returns 1 v = arr2[ 1 ]; // returns 2 

Uint8ClampedArray.prototype.some( predicate[, thisArg] )

Tests whether at least one array element passes a test implemented by a predicate function.

function predicate( v ) { return ( v >= 2 ); } var arr = new Uint8ClampedArray( [ 1, 2 ] ); var bool = arr.some( predicate ); // returns true 

A predicate function is provided three arguments:

• value: array element.
• index: array index.
• arr: array on which the method is invoked.

To set the callback execution context, provide a thisArg.

function predicate( v ) { this.count += 1; return ( v >= 2 ); } var ctx = { 'count': 0 }; var arr = new Uint8ClampedArray( [ 1, 1 ] ); var bool = arr.some( predicate, ctx ); // returns false var n = ctx.count; // returns 2 

Uint8ClampedArray.prototype.sort( [compareFunction] )

Sorts an array in-place (thus mutating the array on which the method is invoked).

var arr = new Uint8ClampedArray( [ 2, 3, 0 ] ); // Sort the array (in ascending order): arr.sort(); var v = arr[ 0 ]; // returns 0 v = arr[ 1 ]; // returns 2 v = arr[ 2 ]; // returns 3 

By default, the method sorts array elements in ascending order. To impose a custom order, provide a compareFunction.

function descending( a, b ) { return b - a; } var arr = new Uint8ClampedArray( [ 2, 3, 0 ] ); // Sort the array (in descending order): arr.sort( descending ); var v = arr[ 0 ]; // returns 3 v = arr[ 1 ]; // returns 2 v = arr[ 2 ]; // returns 0 

The comparison function is provided two array elements, a and b, per invocation, and its return value determines the sort order as follows:

• If the comparison function returns a value less than zero, then the method sorts a to an index lower than b (i.e., a should come before b).
• If the comparison function returns a value greater than zero, then the method sorts a to an index higher than b (i.e., b should come before a).
• If the comparison function returns zero, then the relative order of a and b should remain unchanged.

Uint8ClampedArray.prototype.subarray( [begin[, end]] )

Creates a new typed array view over the same underlying ArrayBuffer and with the same underlying data type as the host array.

var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.subarray(); // returns <Uint8ClampedArray>[ 1, 2, 3 ] var bool = ( arr1.buffer === arr2.buffer ); // returns true 

By default, the method creates a typed array view beginning with the first array element. To specify an alternative array index at which to begin, provide a begin index (inclusive).

var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.subarray( 1 ); // returns <Uint8ClampedArray>[ 2, 3 ] var bool = ( arr1.buffer === arr2.buffer ); // returns true 

By default, the method creates a typed array view which includes all array elements after begin. To limit the number of array elements after begin, provide an end index (exclusive).

var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.subarray( 0, 2 ); // returns <Uint8ClampedArray>[ 1, 2 ] var bool = ( arr1.buffer === arr2.buffer ); // returns true 

When a begin and/or end index is negative, the respective index is determined relative to the last array element.

var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.subarray( -arr1.length, -1 ); // returns <Uint8ClampedArray>[ 1, 2 ] var bool = ( arr1.buffer === arr2.buffer ); // returns true 

If the method is unable to resolve indices to a non-empty array subsequence, the method returns an empty typed array.

var arr1 = new Uint8ClampedArray( [ 1, 2, 3 ] ); var arr2 = arr1.subarray( 10, -1 ); // returns <Uint8ClampedArray>[] 

Uint8ClampedArray.prototype.toLocaleString( [locales[, options]] )

Serializes an array as a locale-specific string.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var str = arr.toLocaleString(); // returns '1,2,3' 

Uint8ClampedArray.prototype.toString()

Serializes an array as a string.

var arr = new Uint8ClampedArray( [ 1, 2, 3 ] ); var str = arr.toString(); // returns '1,2,3' 

Uint8ClampedArray.prototype.values()

Returns an iterator for iterating over array elements.

var arr = new Uint8ClampedArray( [ 1, 2 ] ); // Create an iterator: var it = arr.values(); // Iterate over array elements... var v = it.next().value; // returns 1 v = it.next().value; // returns 2 var bool = it.next().done; // returns true