reverse

Return a view of an input ndarray in which the order of elements along each dimension is reversed.

Usage

var reverse = require( '@stdlib/ndarray/base/reverse' );

reverse( x, writable )

Returns a view of an input ndarray in which the order of elements along each dimension is reversed.

var ndarray = require( '@stdlib/ndarray/ctor' );
var ndarray2array = require( '@stdlib/ndarray/to-array' );

var buffer = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];
var shape = [ 3, 2 ];
var strides = [ 2, 1 ];
var offset = 0;

var x = ndarray( 'generic', buffer, shape, strides, offset, 'row-major' );
// returns <ndarray>

var sh = x.shape;
// returns [ 3, 2 ]

var arr = ndarray2array( x );
// returns [ [ 1.0, 2.0 ], [ 3.0, 4.0 ], [ 5.0, 6.0 ] ]

var y = reverse( x, false );
// returns <ndarray>

sh = y.shape;
// returns [ 3, 2 ]

arr = ndarray2array( y );
// returns [ [ 6.0, 5.0 ], [ 4.0, 3.0 ], [ 2.0, 1.0 ] ]

The function accepts the following arguments:

  • x: input ndarray.
  • writable: boolean indicating whether a returned ndarray should be writable.

Notes

  • The writable parameter only applies to ndarray constructors supporting read-only instances.

Examples

var array = require( '@stdlib/ndarray/array' );
var ndarray2array = require( '@stdlib/ndarray/to-array' );
var zeroTo = require( '@stdlib/array/base/zero-to' );
var reverse = require( '@stdlib/ndarray/base/reverse' );

// Create a linear ndarray buffer:
var buf = zeroTo( 16 );

// Create a one-dimensional ndarray:
var x1 = array( buf, {
    'shape': [ 16 ]
});

// Reverse element order:
var y1 = reverse( x1, false );
// returns <ndarray>

var a1 = ndarray2array( y1 );
// returns [ 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 ]

// Create a two-dimensional ndarray:
var x2 = array( buf, {
    'shape': [ 4, 4 ]
});

// Reverse element order:
var y2 = reverse( x2, false );
// returns <ndarray>

var a2 = ndarray2array( y2 );
// returns [ [ 15, 14, 13, 12 ], [ 11, 10, 9, 8 ], [ 7, 6, 5, 4 ], [ 3, 2, 1, 0 ] ]

// Create a three-dimensional ndarray:
var x3 = array( buf, {
    'shape': [ 2, 4, 2 ]
});

// Reverse element order:
var y3 = reverse( x3, false );
// returns <ndarray>

var a3 = ndarray2array( y3 );
// returns [ [ [ 15, 14 ], [ 13, 12 ], [ 11, 10 ], [ 9, 8 ] ], [ [ 7, 6 ], [ 5, 4 ], [ 3, 2 ], [ 1, 0 ] ] ]
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