blas-dswap
v1.0.0
Published
Interchanges the elements of x and y.
Downloads
3
Maintainers
Readme
dswap
Interchanges the elements of
x
andy
.
Installation
$ npm install blas-dswap
Usage
var swap = require( 'blas-dswap' );
swap( N, x, strideX, offsetX, y, strideY, offsetY )
Interchanges the elements of x
and y
.
var x = [ 1, 2, 3, 4, 5 ];
var y = [ 6, 7, 8, 9, 10 ];
swap( x.length, x, 1, 0, y, 1, 0 );
// x => [ 6, 7, 8, 9, 10 ]
// y => [ 1, 2, 3, 4, 5 ]
The function
accepts the following parameters:
- N: number of elements to swap.
- x: input
array
ortyped array
. - strideX: index increment for
x
. - offsetX: starting index for
x
. - y: input
array
ortyped array
. - strideY: index increment for
y
. - offsetY: starting index for
y
.
The N
, stride
, and offset
parameters determine how elements are interchanged between x
and y
. For example, to swap every other element in x
starting from its second element with the last N
elements in y
starting from its last element,
var x = [ 1, 2, 3, 4, 5, 6 ];
var y = [ 7, 8, 9, 10, 11, 12 ];
var N = Math.floor( x.length / 2 );
swap( N, x, 2, 1, y, -1, y.length-1 );
// x => [ 1, 12, 3, 11, 5, 10 ]
// y => [ 7, 8, 9, 6, 4, 2 ]
If N <= 0
, the function
returns undefined
.
Notes
Examples
var swap = require( 'blas-dswap' );
var x;
var y;
var i;
x = new Float64Array( 10 );
y = new Float64Array( 10 );
for ( i = 0; i < x.length; i++ ) {
x[ i ] = Math.round( Math.random()*500 );
y[ i ] = Math.round( Math.random()*10 );
}
console.log( x );
console.log( y );
// Swap elements such that the element orders are reversed:
swap( x.length, x, 1, 0, y, -1, y.length-1 );
console.log( x );
console.log( y );
To run the example code from the top-level application directory,
$ node ./examples/index.js
Tests
Unit
This repository uses tape for unit tests. To run the tests, execute the following command in the top-level application directory:
$ make test
All new feature development should have corresponding unit tests to validate correct functionality.
Test Coverage
This repository uses Istanbul as its code coverage tool. To generate a test coverage report, execute the following command in the top-level application directory:
$ make test-cov
Istanbul creates a ./reports/coverage
directory. To access an HTML version of the report,
$ make view-cov
Browser Support
This repository uses Testling for browser testing. To run the tests in a (headless) local web browser, execute the following command in the top-level application directory:
$ make test-browsers
To view the tests in a local web browser,
$ make view-browser-tests
License
Copyright
Copyright © 2016. The Compute.io Authors.