put

Replace specified elements of an array with provided values.

Usage

var put = require( '@stdlib/array/base/put' );

put( x, indices, values, mode )

Replaces specified elements of an array with provided values.

var x = [ 1, 2, 3, 4 ];

var out = put( x, [ 1, 3 ], [ 20, 40 ], 'throw' );
// returns [ 1, 20, 3, 40 ]

var bool = ( out === x );
// returns true

The function supports the following parameters:

x: input array.
indices: list of indices.
values: values to set. When indices contains one or more elements, values must be broadcast compatible with indices (i.e., must have either one element or the same number of elements as indices).
mode: index mode.

If indices is an empty array, the function returns the input array unchanged.

var x = [ 1, 2, 3, 4 ];

var out = put( x, [], [ 20, 40 ], 'throw' );
// returns [ 1, 2, 3, 4 ]

The function supports broadcasting a values array containing a single element against an indices array containing one or more elements.

var x = [ 1, 2, 3, 4 ];

var out = put( x, [ 1, 3 ], [ 20 ], 'throw' );
// returns [ 1, 20, 3, 20 ]

var bool = ( out === x );
// returns true

Notes

The function mutates the input array x.
Because each index is only validated at the time of replacing a particular element, mutation may occur even when one or more indices are out-of-bounds, including when the index mode indicates to raise an exception.

Examples

var filledBy = require( '@stdlib/array/base/filled-by' );
var discreteUniform = require( '@stdlib/random/base/discrete-uniform' );
var linspace = require( '@stdlib/array/base/linspace' );
var put = require( '@stdlib/array/base/put' );

// Generate a linearly spaced array:
var x = linspace( 0, 100, 11 );
console.log( x );

// Generate an array of random indices:
var N = discreteUniform( 5, 15 );
var indices = filledBy( N, discreteUniform.factory( 0, x.length-1 ) );
console.log( indices );

// Generate an array of random values:
var values = filledBy( N, discreteUniform.factory( 1000, 2000 ) );
console.log( values );

// Update a random sample of elements in `x`:
var out = put( x, indices, values, 'throw' );
console.log( out );