Press n or j to go to the next uncovered block, b, p or k for the previous block.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 | 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x | /**
* @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 isNonNegativeInteger = require( '@stdlib/assert/is-nonnegative-integer' ).isPrimitive;
var isCollection = require( '@stdlib/assert/is-collection' );
var strides2offset = require( '@stdlib/ndarray/base/strides2offset' );
var format = require( '@stdlib/string/format' );
// MAIN //
/**
* Returns the index offset specifying the underlying buffer index of the first iterated ndarray element.
*
* @param {ndarrayLike} x - input ndarray
* @throws {TypeError} must provide an 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 n;
// Note: we intentionally avoid rigorous ndarray checks to minimize performance impacts. This obviously means that non-ndarray-like objects can sneak through, but this is likely all right for the purposes of this function...
if ( typeof x !== 'object' || x === null ) {
throw new TypeError( format( 'invalid argument. Must provide an ndarray. Value: `%s`.', x ) );
}
n = x.offset;
if ( isNonNegativeInteger( n ) ) {
return n;
}
sh = x.shape;
if ( !isCollection( sh ) ) {
throw new TypeError( format( 'invalid argument. Must provide an ndarray. Value: `%s`.', x ) );
}
st = x.strides;
if ( sh.length === 0 || !isCollection( st ) ) {
return 0;
}
n = strides2offset( sh, st );
if ( isNonNegativeInteger( n ) ) {
return n;
}
throw new TypeError( format( 'invalid argument. Must provide an ndarray. Value: `%s`.', x ) );
}
// EXPORTS //
module.exports = offset;
|