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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 | 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 45x 45x 45x 45x 45x 45x 45x 45x 45x 4x 4x 45x 4x 4x 45x 3x 3x 45x 3x 3x 45x 3x 3x 45x 3x 3x 45x 1x 1x 45x 1x 1x 45x 1x 1x 22x 45x 6x 6x 45x 10x 10x 45x 6x 6x 6x 16x 16x 45x 7x 7x 45x 9x 9x 9x 16x 45x 2x 2x 2x 2x 2x | /**
* @license Apache-2.0
*
* Copyright (c) 2025 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-params */
'use strict';
// MODULES //
var stride2offset = require( '@stdlib/strided/base/stride2offset' );
var isLayout = require( '@stdlib/blas/base/assert/is-layout' );
var isMatrixTranspose = require( '@stdlib/blas/base/assert/is-transpose-operation' );
var format = require( '@stdlib/string/format' );
var base = require( './base.js' );
// MAIN //
/**
* Performs one of the matrix-vector operations `y := α*A*x + β*y, or y := α*A**T*x + β*y`, where `α` and `β` are scalars, `x` and `y` are vectors and `A` is an `M` by `N` band matrix, with `KL` sub-diagonals and `KU` super-diagonals.
* @param {string} order - storage layout
* @param {string} trans - specifies whether `A` should be transposed, conjugate-transposed, or not transposed
* @param {NonNegativeInteger} M - number of rows in the matrix `A`
* @param {NonNegativeInteger} N - number of columns in the matrix `A`
* @param {NonNegativeInteger} KL - number of sub-diagonals of matrix `A`
* @param {NonNegativeInteger} KU - number of super-diagonals of matrix `A`
* @param {number} alpha - scalar constant
* @param {Float64Array} A - input matrix
* @param {PositiveInteger} LDA - stride of the first dimension of `A` (a.k.a., leading dimension of the matrix `A`)
* @param {Float64Array} x - first input vector
* @param {integer} strideX - `x` stride length
* @param {number} beta - scalar constant
* @param {Float64Array} y - second input vector
* @param {integer} strideY - `y` stride length
* @throws {TypeError} first argument must be a valid order
* @throws {TypeError} second argument must be a valid transpose operation
* @throws {RangeError} third argument must be a nonnegative integer
* @throws {RangeError} fourth argument must be a nonnegative integer
* @throws {RangeError} seventh argument must be greater than or equal KL + KU + 1
* @throws {RangeError} ninth argument must be non-zero
* @throws {RangeError} twelfth argument must be non-zero
* @returns {Float64Array} `y`
*
* @example
* var Float64Array = require( '@stdlib/array/float64' );
*
* var A = new Float64Array( [ 0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 0.0 ] );
* var x = new Float64Array( [ 1.0, 1.0, 1.0 ] );
* var y = new Float64Array( [ 0.0, 0.0, 0.0 ] );
*
* dgbmv( 'row-major', 'no-transpose', 3, 3, 1, 1, 1.0, A, 3, x, 1, 1.0, y, 1 );
* // y => <Float64Array>[ 3.0, 12.0, 13.0 ]
*/
function dgbmv( order, trans, M, N, KL, KU, alpha, A, LDA, x, strideX, beta, y, strideY ) { // eslint-disable-line max-len
var xlen;
var ylen;
var sa1;
var sa2;
var ox;
var oy;
if ( !isLayout( order ) ) {
throw new TypeError( format( 'invalid argument. First argument must be a valid order. Value: `%s`.', order ) );
}
if ( !isMatrixTranspose( trans ) ) {
throw new TypeError( format( 'invalid argument. Second argument must be a valid transpose operation. Value: `%s`.', trans ) );
}
if ( M < 0 ) {
throw new RangeError( format( 'invalid argument. Third argument must be a nonnegative integer. Value: `%d`.', M ) );
}
if ( N < 0 ) {
throw new RangeError( format( 'invalid argument. Fourth argument must be a nonnegative integer. Value: `%d`.', N ) );
}
if ( KL < 0 ) {
throw new RangeError( format( 'invalid argument. Fifth argument must be a nonnegative integer. Value: `%d`.', KL ) );
}
if ( KU < 0 ) {
throw new RangeError( format( 'invalid argument. Sixth argument must be a nonnegative integer. Value: `%d`.', KU ) );
}
if ( LDA < KL + KU + 1 ) {
throw new RangeError( format( 'invalid argument. ninth argument is not a valid integer. Value: `%d`.', KU ) );
}
if ( strideX === 0 ) {
throw new RangeError( format( 'invalid argument. Eleventh argument must be non-zero.' ) );
}
if ( strideY === 0 ) {
throw new RangeError( format( 'invalid argument. Fourteenth argument must be non-zero.' ) );
}
// Check if we can early return...
if ( M === 0 || N === 0 || ( alpha === 0.0 && beta === 1.0 ) ) {
return y;
}
if ( trans === 'no-transpose' ) {
xlen = N;
ylen = M;
} else {
xlen = M;
ylen = N;
}
ox = stride2offset( xlen, strideX );
oy = stride2offset( ylen, strideY );
if ( order === 'column-major' ) {
sa1 = 1;
sa2 = LDA;
} else { // order === 'row-major'
sa1 = LDA;
sa2 = 1;
}
return base( trans, M, N, KL, KU, alpha, A, sa1, sa2, 0, x, strideX, ox, beta, y, strideY, oy ); // eslint-disable-line max-len
}
// EXPORTS //
module.exports = dgbmv;
|