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/**
* @license Apache-2.0
*
* Copyright (c) 2026 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*    http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
 
'use strict';
 
// MODULES //
 
var ndarraylike2scalar = require( '@stdlib/ndarray/base/ndarraylike2scalar' );
var numelDimension = require( '@stdlib/ndarray/base/numel-dimension' );
var getStride = require( '@stdlib/ndarray/base/stride' );
var getOffset = require( '@stdlib/ndarray/base/offset' );
var getData = require( '@stdlib/ndarray/base/data-buffer' );
var strided = require( '@stdlib/blas/ext/base/ddiff' ).ndarray;
 
 
// MAIN //
 
/**
* Calculates the k-th discrete forward difference of a one-dimensional double-precision floating-point ndarray.
*
* ## Notes
*
* -   The function expects the following ndarrays:
*
*     -   a one-dimensional input ndarray.
*     -   a one-dimensional ndarray containing values to prepend.
*     -   a one-dimensional ndarray containing values to append.
*     -   a one-dimensional output ndarray.
*     -   a one-dimensional workspace ndarray.
*     -   a zero-dimensional ndarray specifying the number of times to recursively compute differences.
*
* @param {ArrayLikeObject<Object>} arrays - array-like object containing ndarrays
* @returns {ndarray} output ndarray
*
* @example
* var Float64Vector = require( '@stdlib/ndarray/vector/float64' );
* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
*
* var x = new Float64Vector( [ 2.0, 4.0, 6.0, 8.0, 10.0 ] );
* var prepend = new Float64Vector( [ 1.0 ] );
* var append = new Float64Vector( [ 11.0 ] );
* var out = new Float64Vector( 6 );
* var workspace = new Float64Vector( 6 );
* var k = scalar2ndarray( 1, {
*     'dtype': 'generic'
* });
*
* var y = ddiff( [ x, prepend, append, out, workspace, k ] );
* // returns <ndarray>[ 1.0, 2.0, 2.0, 2.0, 2.0, 1.0 ]
*/
function ddiff( arrays ) {
	var workspace;
	var prepend;
	var append;
	var out;
	var wo;
	var ws;
	var wd;
	var po;
	var ps;
	var pd;
	var oo;
	var os;
	var od;
	var ao;
	var as;
	var ad;
	var N2;
	var N1;
	var xo;
	var xs;
	var xd;
	var N;
	var x;
	var k;
 
	x = arrays[ 0 ];
	prepend = arrays[ 1 ];
	append = arrays[ 2 ];
	out = arrays[ 3 ];
	workspace = arrays[ 4 ];
	k = ndarraylike2scalar( arrays[ 5 ] );
 
	// Resolve number of indexed elements...
	N = numelDimension( x, 0 );
	N1 = numelDimension( prepend, 0 );
	N2 = numelDimension( append, 0 );
 
	// Resolve the array data...
	xd = getData( x );
	pd = getData( prepend );
	ad = getData( append );
	od = getData( out );
	wd = getData( workspace );
 
	// Resolve the array strides...
	xs = getStride( x, 0 );
	ps = getStride( prepend, 0 );
	as = getStride( append, 0 );
	os = getStride( out, 0 );
	ws = getStride( workspace, 0 );
 
	// Resolve the array offsets...
	xo = getOffset( x );
	po = getOffset( prepend );
	ao = getOffset( append );
	oo = getOffset( out );
	wo = getOffset( workspace );
 
	strided( N, k, xd, xs, xo, N1, pd, ps, po, N2, ad, as, ao, od, os, oo, wd, ws, wo ); // eslint-disable-line max-len
	return out;
}
 
 
// EXPORTS //
 
module.exports = ddiff;