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 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 | 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 62x 62x 62x 62x 62x 62x 62x 62x 62x 62x 62x 31x 31x 31x 31x 31x 62x 22x 49x 60x 60x 49x 49x 49x 22x 22x 62x 25x 33x 33x 25x 25x 25x 9x 62x 3x 3x 3x 3x 3x | /**
* @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.
*/
/* eslint-disable max-len, max-params */
'use strict';
// MODULES //
var isRowMajor = require( '@stdlib/ndarray/base/assert/is-row-major' );
var arraylike2object = require( '@stdlib/array/base/arraylike2object' );
var max = require( '@stdlib/math/base/special/fast/max' );
var min = require( '@stdlib/math/base/special/fast/min' );
var accessors = require( './accessors.js' );
// MAIN //
/**
* Reflects the lower triangular part of a matrix `A` into the upper triangular part of another matrix `B`.
*
* @private
* @param {NonNegativeInteger} M - number of rows in matrix `A`
* @param {NonNegativeInteger} N - number of columns in matrix `A`
* @param {integer} k - diagonal above which to ignore
* @param {Collection} A - input matrix
* @param {integer} strideA1 - stride of the first dimension of `A`
* @param {integer} strideA2 - stride of the second dimension of `A`
* @param {NonNegativeInteger} offsetA - starting index for `A`
* @param {Collection} B - output matrix
* @param {integer} strideB1 - stride of the first dimension of `B`
* @param {integer} strideB2 - stride of the second dimension of `B`
* @param {NonNegativeInteger} offsetB - starting index for `B`
* @returns {Collection} `B`
*
* @example
* var A = [ 1.0, 2.0, 3.0, 4.0 ];
* var B = [ 0.0, 0.0, 0.0, 0.0 ];
*
* gtril2triu( 2, 2, 0, A, 2, 1, 0, B, 2, 1, 0 );
* // B => [ 1.0, 3.0, 0.0, 4.0 ]
*
* @example
* var A = [ 1.0, 2.0, 3.0, 4.0 ];
* var B = [ 0.0, 0.0, 0.0, 0.0 ];
*
* gtril2triu( 2, 2, -1, A, 2, 1, 0, B, 2, 1, 0 );
* // B => [ 0.0, 3.0, 0.0, 0.0 ]
*/
function gtril2triu( M, N, k, A, strideA1, strideA2, offsetA, B, strideB1, strideB2, offsetB ) {
var oa;
var ob;
var ia;
var ib;
var i0;
var i1;
oa = arraylike2object( A );
ob = arraylike2object( B );
if ( oa.accessorProtocol || ob.accessorProtocol ) {
accessors( M, N, k, oa, strideA1, strideA2, offsetA, ob, strideB1, strideB2, offsetB );
return B;
}
ia = offsetA;
ib = offsetB;
if ( isRowMajor( [ strideA1, strideA2 ] ) ) {
for ( i1 = 0; i1 < M; i1++ ) {
for ( i0 = 0; i0 <= min( i1+k, N-1 ); i0++ ) {
B[ ib+(i0*strideB1) ] = A[ ia+(i0*strideA2) ];
}
ia += strideA1;
ib += strideB2;
}
return B;
}
for ( i1 = 0; i1 < N; i1++ ) {
for ( i0 = max( 0, i1-k ); i0 < M; i0++ ) {
B[ ib+(i0*strideB2) ] = A[ ia+(i0*strideA1) ];
}
ia += strideA2;
ib += strideB1;
}
return B;
}
// EXPORTS //
module.exports = gtril2triu;
|