time-to-botec/squiggle/node_modules/@stdlib/ndarray/base/assert/is-buffer-length-compatible/README.md

isBufferLengthCompatible

Determine if a buffer length is compatible with ndarray meta data.

Usage

var isBufferLengthCompatible = require( '@stdlib/ndarray/base/assert/is-buffer-length-compatible' );

isBufferLengthCompatible( len, shape, strides, offset )

Returns a boolean indicating if a buffer length is compatible with provided ndarray meta data.

var shape = [ 2, 2 ];
var strides = [ 2, 1 ];
var offset = 25;

var bool = isBufferLengthCompatible( 30, shape, strides, offset );
// returns true

bool = isBufferLengthCompatible( 4, shape, strides, offset );
// returns false

Examples

var discreteUniform = require( '@stdlib/random/base/discrete-uniform' );
var shape2strides = require( '@stdlib/ndarray/base/shape2strides' );
var strides2offset = require( '@stdlib/ndarray/base/strides2offset' );
var randu = require( '@stdlib/random/base/randu' );
var isBufferLengthCompatible = require( '@stdlib/ndarray/base/assert/is-buffer-length-compatible' );

var strides;
var offset;
var shape;
var bool;
var len;
var i;
var j;

len = 500; // buffer length
shape = [ 0, 0, 0 ];

for ( i = 0; i < 100; i++ ) {
    // Generate a random array shape:
    shape[ 0 ] = discreteUniform( 1, 10 );
    shape[ 1 ] = discreteUniform( 1, 10 );
    shape[ 2 ] = discreteUniform( 1, 10 );

    // Generate 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;

    // Compute the index offset:
    offset = strides2offset( shape, strides ) + discreteUniform( 0, 200 );

    // Determine if a buffer length is compatible with generated meta data:
    bool = isBufferLengthCompatible( len, shape, strides, offset );
    console.log( 'Buffer length: %d. Shape: %s. Strides: %s. Offset: %d. Compatible: %s.', len, shape.join( 'x' ), strides.join( ',' ), offset, bool );
}