time-to-botec/squiggle/node_modules/@stdlib/ndarray/base/max-view-buffer-index/README.md

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@license Apache-2.0
Copyright (c) 2018 The Stdlib Authors.
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# Max View Buffer Index
> Compute the maximum linear index in an underlying data buffer accessible to an array view.
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## Usage
```javascript
var maxViewBufferIndex = require( '@stdlib/ndarray/base/max-view-buffer-index' );
```
#### maxViewBufferIndex( shape, strides, offset )
Computes the maximum linear index in an underlying data buffer accessible to an array view.
```javascript
// 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 = 0;
var idx = maxViewBufferIndex( shape, strides, offset );
// returns 3
```
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## Examples
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```javascript
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 maxViewBufferIndex = require( '@stdlib/ndarray/base/max-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 );
// Compute the maximum linear index:
idx = maxViewBufferIndex( shape, strides, offset );
console.log( 'Shape: %s. Strides: %s. Offset: %d. Max idx: %d.', shape.join( 'x' ), strides.join( ',' ), offset, idx );
}
```
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