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@stdlib/ndarray-base-offset

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Return the index offset specifying the underlying buffer index of the first iterated ndarray element.

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/** * @license Apache-2.0 * * Copyright (c) 2023 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 strides2offset = require( '@stdlib/ndarray-base-strides2offset' ); // MAIN // /** * Returns the index offset specifying the underlying buffer index of the first iterated ndarray element. * * @param {ndarrayLike} x - input ndarray * @returns {NonNegativeInteger} index offset * * @example * var zeros = require( '@stdlib/ndarray-zeros' ); * * var n = offset( zeros( [ 3, 3, 3 ] ) ); * // returns 0 */ function offset( x ) { var st; var sh; var o; o = x.offset; if ( typeof o === 'number' ) { return o; } sh = x.shape; if ( sh.length === 0 ) { return 0; } st = x.strides; if ( typeof st !== 'object' || st === null ) { return 0; } return strides2offset( sh, st ); } // EXPORTS // module.exports = offset;