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Interchange two single-precision floating-point vectors.
npm install @stdlib/blas-base-sswapAlternatively,
- To load the package in a website via a
scripttag without installation and bundlers, use the ES Module available on theesmbranch (see README). - If you are using Deno, visit the
denobranch (see README for usage intructions). - For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the
umdbranch (see README).
The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.
To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.
var sswap = require( '@stdlib/blas-base-sswap' );Interchanges vectors x and y.
var Float32Array = require( '@stdlib/array-float32' );
var x = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0 ] );
var y = new Float32Array( [ 6.0, 7.0, 8.0, 9.0, 10.0 ] );
sswap( x.length, x, 1, y, 1 );
// x => <Float32Array>[ 6.0, 7.0, 8.0, 9.0, 10.0 ]
// y => <Float32Array>[ 1.0, 2.0, 3.0, 4.0, 5.0 ]The function has the following parameters:
- N: number of indexed elements.
- x: first input
Float32Array. - strideX: index increment for
x. - y: second input
Float32Array. - strideY: index increment for
y.
The N and stride parameters determine how values from the strided arrays are accessed at runtime. For example, to swap in reverse order every other value in x with the first N elements of y,
var Float32Array = require( '@stdlib/array-float32' );
var x = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
var y = new Float32Array( [ 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] );
sswap( 3, x, -2, y, 1 );
// x => <Float32Array>[ 9.0, 2.0, 8.0, 4.0, 7.0, 6.0 ]
// y => <Float32Array>[ 5.0, 3.0, 1.0, 10.0, 11.0, 12.0 ]Note that indexing is relative to the first index. To introduce an offset, use typed array views.
var Float32Array = require( '@stdlib/array-float32' );
// Initial arrays...
var x0 = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
var y0 = new Float32Array( [ 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] );
// Create offset views...
var x1 = new Float32Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
var y1 = new Float32Array( y0.buffer, y0.BYTES_PER_ELEMENT*3 ); // start at 4th element
// Swap in reverse order every other value from `x1` with `y1`...
sswap( 3, x1, -2, y1, 1 );
// x0 => <Float32Array>[ 1.0, 12.0, 3.0, 11.0, 5.0, 10.0 ]
// y0 => <Float32Array>[ 7.0, 8.0, 9.0, 6.0, 4.0, 2.0 ]Interchanges vectors x and y using alternative indexing semantics.
var Float32Array = require( '@stdlib/array-float32' );
var x = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0 ] );
var y = new Float32Array( [ 6.0, 7.0, 8.0, 9.0, 10.0 ] );
sswap.ndarray( x.length, x, 1, 0, y, 1, 0 );
// x => <Float32Array>[ 6.0, 7.0, 8.0, 9.0, 10.0 ]
// y => <Float32Array>[ 1.0, 2.0, 3.0, 4.0, 5.0 ]The function has the following additional parameters:
- offsetX: starting index for
x. - offsetY: starting index for
y.
While typed array views mandate a view offset based on the underlying buffer, the offset parameters support indexing semantics based on starting indices. For example, to swap every other value in x starting from the second value with the last N elements in y where x[i] = y[n], x[i+2] = y[n-1],...,
var Float32Array = require( '@stdlib/array-float32' );
var x = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
var y = new Float32Array( [ 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] );
sswap.ndarray( 3, x, 2, 1, y, -1, y.length-1 );
// x => <Float32Array>[ 1.0, 12.0, 3.0, 11.0, 5.0, 10.0 ]
// y => <Float32Array>[ 7.0, 8.0, 9.0, 6.0, 4.0, 2.0 ]var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var sswap = require( '@stdlib/blas-base-sswap' );
var opts = {
'dtype': 'float32'
};
var x = discreteUniform( 10, 0, 500, opts );
console.log( x );
var y = discreteUniform( x.length, 0, 255, opts );
console.log( y );
// Swap elements in `x` and `y` starting from the end of `y`:
sswap( x.length, x, 1, y, -1 );
console.log( x );
console.log( y );#include "stdlib/blas/base/sswap.h"Interchanges two single-precision floating-point vectors.
float x[] = { 1.0f, 2.0f, 3.0f, 4.0f, 5.0f };
float y[] = { 6.0f, 7.0f, 8.0f, 9.0f, 10.0f };
c_sswap( 5, x, 1, y, 1 );The function accepts the following arguments:
- N:
[in] CBLAS_INTnumber of indexed elements. - X:
[inout] float*first input array. - strideX:
[in] CBLAS_INTindex increment forX. - Y:
[inout] float*second input array. - strideY:
[in] CBLAS_INTindex increment forY.
void c_sswap( const CBLAS_INT N, float *X, const CBLAS_INT strideX, float *Y, const CBLAS_INT strideY );Interchanges two single-precision floating-point vectors using alternative indexing semantics.
float x[] = { 1.0f, 2.0f, 3.0f, 4.0f, 5.0f };
float y[] = { 6.0f, 7.0f, 8.0f, 9.0f, 10.0f };
c_sswap_ndarray( 3, x, 1, 2, y, 1, 2 );The function accepts the following arguments:
- N:
[in] CBLAS_INTnumber of indexed elements. - X:
[inout] float*first input array. - strideX:
[in] CBLAS_INTindex increment forX. - offsetX:
[in] CBLAS_INTstarting index forX. - Y:
[inout] float*second input array. - strideY:
[in] CBLAS_INTindex increment forY. - offsetY:
[in] CBLAS_INTstarting index forY.
void c_sswap_ndarray( const CBLAS_INT N, float *X, const CBLAS_INT strideX, const CBLAS_INT offsetX, float *Y, const CBLAS_INT strideY, CBLAS_INT offsetY );#include "stdlib/blas/base/sswap.h"
#include <stdio.h>
int main( void ) {
// Create strided arrays:
float x[] = { 1.0f, 2.0f, 3.0f, 4.0f, 5.0f, 6.0f, 7.0f, 8.0f };
float y[] = { 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f };
// Specify the number of indexed elements:
const int N = 4;
// Specify stride lengths:
const int strideX = 2;
const int strideY = -2;
// Interchange elements:
c_sswap( N, x, strideX, y, strideY );
// Print the result:
for ( int i = 0; i < 8; i++ ) {
printf( "x[ %i ] = %f\n", i, x[ i ] );
printf( "y[ %i ] = %f\n", i, y[ i ] );
}
// Interchange elements:
c_sswap_ndarray( N, x, strideX, 0, y, strideY, 6 );
// Print the result:
for ( int i = 0; i < 8; i++ ) {
printf( "x[ %i ] = %f\n", i, x[ i ] );
printf( "y[ %i ] = %f\n", i, y[ i ] );
}
}@stdlib/blas-base/dswap: interchange two double-precision floating-point vectors.@stdlib/blas-base/gswap: interchange two vectors.@stdlib/blas-base/scopy: copy values from x into y.@stdlib/blas-sswap: interchange two single-precision floating-point vectors.
This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.
See LICENSE.
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