Return a view of an input ndarray in which the order of elements along the second-to-last dimension is reversed.
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> Return a view of an input ndarray in which the order of elements along the second-to-last dimension is reversed.
``bash`
npm install @stdlib/ndarray-base-flipud
`javascript`
var flipud = require( '@stdlib/ndarray-base-flipud' );
#### flipud( x, writable )
Returns a view of an input ndarray in which the order of elements along the second-to-last dimension is reversed.
`javascript
var ndarray = require( '@stdlib/ndarray-ctor' );
var getShape = require( '@stdlib/ndarray-shape' );
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
var sh = getShape( x );
// returns [ 3, 2 ]
var y = flipud( x, false );
// returns
sh = getShape( y );
// returns [ 3, 2 ]
`
The function accepts the following arguments:
- x: input ndarray.
- writable: boolean indicating whether a returned ndarray should be writable.
- If provided a zero-dimensional ndarray, as the ndarray has no dimensions to reverse, the function simply returns a new view of the input ndarray. Similarly, if provided a one-dimensional ndarray, as the ndarray has only one dimension, the function simply returns a new view of the input ndarray.
- The writable parameter only applies to ndarray constructors supporting read-only instances.
`javascript
var array = require( '@stdlib/ndarray-array' );
var ndarray2array = require( '@stdlib/ndarray-to-array' );
var zeroTo = require( '@stdlib/array-base-zero-to' );
var flipud = require( '@stdlib/ndarray-base-flipud' );
// Create a linear ndarray buffer:
var buf = zeroTo( 16 );
// Create a three-dimensional ndarray:
var x = array( buf, {
'shape': [ 2, 4, 2 ]
});
// Reverse the order of second-to-last dimension:
var y = flipud( x, false );
// returns
var arr = ndarray2array( y );
// returns [ [ [ 6, 7 ], [ 4, 5 ], [ 2, 3 ], [ 0, 1 ] ], [ [ 14, 15 ], [ 12, 13 ], [ 10, 11 ], [ 8, 9 ] ] ]
`
*
This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
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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