Determine the order of a multidimensional array based on a provided stride array.
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Determine the order of a multidimensional array based on a provided stride array.
bash
npm install @stdlib/ndarray-base-strides2orderscript tag without installation and bundlers, use the [ES Module][es-module] available on the [esm][esm-url] branch (see [README][esm-readme]).deno][deno-url] branch (see [README][deno-readme] for usage intructions).umd][umd-url] branch (see [README][umd-readme]).javascript
var strides2order = require( '@stdlib/ndarray-base-strides2order' );javascript
var order = strides2order( [ 2, 1 ] );
// returns 1
order = strides2order( [ 1, 2 ] );
// returns 2
order = strides2order( [ 3 ] );
// returns 3
order = strides2order( [ 1, 3, 2 ] );
// returns 0
order = strides2order( [] );
// returns 01: based on the stride array, the array is in row-major order.2: based on the stride array, the array is in column-major order.3: based on the stride array, the array is in both row-major and column-major order.0: based on the stride array, the array is in neither row-major nor column-major order.javascript
var discreteUniform = require( '@stdlib/random-base-discrete-uniform' );
var shape2strides = require( '@stdlib/ndarray-base-shape2strides' );
var randu = require( '@stdlib/random-base-randu' );
var strides2order = require( '@stdlib/ndarray-base-strides2order' );
var strides;
var order;
var shape;
var i;
var j;
shape = [ 0, 0, 0 ];
for ( i = 0; i < 20; i++ ) {
// Generate a random array shape:
shape[ 0 ] = discreteUniform( 1, 10 );
shape[ 1 ] = discreteUniform( 1, 10 );
shape[ 2 ] = discreteUniform( 1, 10 );
// Compute the strides:
if ( randu() < 0.5 ) {
strides = shape2strides( shape, 'row-major' );
} else {
strides = shape2strides( shape, 'column-major' );
}
j = discreteUniform( 0, shape.length-1 );
strides[ j ] *= ( randu() < 0.5 ) ? -1 : 1;
// Determine the order:
order = strides2order( strides );
console.log( 'Strides: %s. Order: %s.', strides.join( ',' ), order );
}
