Return a read-only view of an input ndarray where the dimensions of the input ndarray are expanded to a specified dimensionality by spreading dimensions to specified dimension indices and inserting dimensions of size one for the remaining dimensions.
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> Return a read-only view of an input [ndarray][@stdlib/ndarray/ctor] where the dimensions of the input [ndarray][@stdlib/ndarray/ctor] are expanded to a specified dimensionality by spreading dimensions to specified dimension indices and inserting dimensions of size one for the remaining dimensions.
``bash`
npm install @stdlib/ndarray-spread-dimensions
`javascript`
var spreadDimensions = require( '@stdlib/ndarray-spread-dimensions' );
#### spreadDimensions( ndims, x, dims )
Returns a read-only view of an input [ndarray][@stdlib/ndarray/ctor] where the dimensions of the input [ndarray][@stdlib/ndarray/ctor] are expanded to a specified dimensionality by spreading dimensions to specified dimension indices and inserting dimensions of size one for the remaining dimensions.
`javascript
var ndarray2array = require( '@stdlib/ndarray-to-array' );
var array = require( '@stdlib/ndarray-array' );
// Create a 2x2 ndarray:
var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
// returns
// Prepend a singleton dimension:
var y = spreadDimensions( 3, x, [ 1, 2 ] );
// returns
// Append a singleton dimension:
y = spreadDimensions( 3, x, [ 0, 1 ] );
// returns
// Insert a singleton dimension:
y = spreadDimensions( 3, x, [ 0, 2 ] );
// returns
`
The function accepts the following arguments:
- ndims: number of dimensions in the output [ndarray][@stdlib/ndarray/ctor]. Must be greater than or equal to the number of dimensions in the input [ndarray][@stdlib/ndarray/ctor].
- x: input [ndarray][@stdlib/ndarray/ctor].
- dims: dimension indices specifying where to place the dimensions of the input [ndarray][@stdlib/ndarray/ctor]. Must resolve to normalized indices arranged in ascending order.
`javascript
var uniform = require( '@stdlib/random-uniform' );
var ndarray2array = require( '@stdlib/ndarray-to-array' );
var spreadDimensions = require( '@stdlib/ndarray-spread-dimensions' );
var x = uniform( [ 3, 3, 3 ], -10.0, 10.0 );
console.log( ndarray2array( x ) );
var y = spreadDimensions( 5, x, [ 0, 1, 2 ] );
console.log( ndarray2array( y ) );
`
*
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For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].
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---
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