Memoized Constructor

Create a memoized multidimensional array constructor.

Usage

var ctor = require( '@stdlib/ndarray/base/memoized-ctor' );

ctor( dtype, ndims[, options] )

Returns a memoized multidimensional array constructor customized according to an underlying data type dtype and the number of array dimensions ndims.

var f1 = ctor( 'float64', 3 );
// returns <Function>

var f2 = ctor( 'float64', 3 );
// returns <Function>

var bool = ( f1 === f2 );
// returns true

The function accepts the same arguments and options as, and, with the exception of constructor caching, behaves identically to, @stdlib/ndarray/base/ctor.

Notes

  • Using memoized constructors can provide a performance boost when repeatedly creating ndarray base constructors.

Examples

var Float32Array = require( '@stdlib/array/float32' );
var ctor = require( '@stdlib/ndarray/base/memoized-ctor' );

// Create a memoized ndarray constructor for a 4-dimensional array containing single-precision floating-point numbers:
var ndarray = ctor( 'float32', 4 );

// Create a data buffer:
var buffer = new Float32Array( (3*3*3*3) + 100 );

// Specify the array shape:
var shape = [ 3, 3, 3, 3 ];

// Specify the array strides:
var strides = [ 27, 9, 3, 1 ];

// Specify the index offset:
var offset = 4;

// Specify the order:
var order = 'row-major'; // C-style

// Create a new ndarray:
var arr = ndarray( buffer, shape, strides, offset, order );

// Retrieve an array value:
var v = arr.get( 1, 2, 1, 2 );
// returns 0.0

// Set an array value:
arr.set( 1, 2, 1, 2, 10.0 );

// Retrieve the array value:
v = arr.get( 1, 2, 1, 2 );
// returns 10.0

// Serialize the array as a string:
var str = arr.toString();
// returns "ndarray( new Float32Array( [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ] ), [ 3, 3, 3, 3 ], [ 27, 9, 3, 1 ], 0, 'row-major' )"

// Serialize the array as JSON:
str = JSON.stringify( arr.toJSON() );
// returns '{"type":"ndarray","dtype":"float32","flags":{},"order":"row-major","shape":[3,3,3,3],"strides":[27,9,3,1],"data":[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,10,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]}'