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    @stdlib/ndarray-base-min-view-buffer-index
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    0.0.8 • Public • Published

    Min View Buffer Index

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    Compute the minimum linear index in an underlying data buffer accessible to an array view.

    Installation

    npm install @stdlib/ndarray-base-min-view-buffer-index

    Usage

    var minViewBufferIndex = require( '@stdlib/ndarray-base-min-view-buffer-index' );

    minViewBufferIndex( shape, strides, offset )

    Computes the minimum linear index in an underlying data buffer accessible to an array view.

    // Array shape:
    var shape = [ 2, 2 ];
    
    // Stride array:
    var strides = [ -2, -1 ];
    
    // Index offset which specifies the location of the first indexed value:
    var offset = 13; // includes a view offset
    
    var idx = minViewBufferIndex( shape, strides, offset );
    // returns 10

    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 minViewBufferIndex = require( '@stdlib/ndarray-base-min-view-buffer-index' );
    
    var strides;
    var offset;
    var shape;
    var idx;
    var i;
    var j;
    
    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 ) + 25; // include view offset
    
        // Compute the minimum linear index:
        idx = minViewBufferIndex( shape, strides, offset );
        console.log( 'Shape: %s. Strides: %s. Offset: %d. Min idx: %d.', shape.join( 'x' ), strides.join( ',' ), offset, idx );
    }

    Notice

    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.

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    License

    See LICENSE.

    Copyright

    Copyright © 2016-2022. The Stdlib Authors.

    Install

    npm i @stdlib/ndarray-base-min-view-buffer-index

    Homepage

    stdlib.io

    DownloadsWeekly Downloads

    27

    Version

    0.0.8

    License

    Apache-2.0

    Unpacked Size

    45.7 kB

    Total Files

    12

    Last publish

    Collaborators

    • stdlib-bot
    • kgryte
    • planeshifter
    • rreusser