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 | 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 49x 49x 49x 49x 49x 49x 49x 49x 12x 12x 37x 37x 49x 16x 16x 16x 21x 21x 21x 21x 49x 12x 12x 12x 12x 10x 20x 20x 20x 20x 10x 12x 4x 4x 12x 114x 114x 114x 114x 114x 114x 114x 8x 8x 49x 27x 27x 27x 27x 9x 49x 3x 3x 3x 3x 3x | /**
* @license Apache-2.0
*
* Copyright (c) 2018 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 arraylike2object = require( '@stdlib/array/base/arraylike2object' );
var accessors = require( './accessors.js' );
// VARIABLES //
var M = 4;
// MAIN //
/**
* Multiplies `x` by a constant and adds the result to `y`.
*
* @param {PositiveInteger} N - number of indexed elements
* @param {number} alpha - scalar constant
* @param {NumericArray} x - input array
* @param {integer} strideX - `x` stride length
* @param {NonNegativeInteger} offsetX - starting `x` index
* @param {NumericArray} y - output array
* @param {integer} strideY - `y` stride length
* @param {NonNegativeInteger} offsetY - starting `y` index
* @returns {NumericArray} output array
*
* @example
* var x = [ 1.0, 2.0, 3.0, 4.0, 5.0 ];
* var y = [ 1.0, 1.0, 1.0, 1.0, 1.0 ];
* var alpha = 5.0;
*
* gaxpy( x.length, alpha, x, 1, 0, y, 1, 0 );
* // y => [ 6.0, 11.0, 16.0, 21.0, 26.0 ]
*/
function gaxpy( N, alpha, x, strideX, offsetX, y, strideY, offsetY ) {
var ix;
var iy;
var ox;
var oy;
var m;
var i;
if ( N <= 0 || alpha === 0.0 ) {
return y;
}
ox = arraylike2object( x );
oy = arraylike2object( y );
if ( ox.accessorProtocol || oy.accessorProtocol ) {
accessors( N, alpha, ox, strideX, offsetX, oy, strideY, offsetY );
return oy.data;
}
ix = offsetX;
iy = offsetY;
// Use unrolled loops if both strides are equal to `1`...
if ( strideX === 1 && strideY === 1 ) {
m = N % M;
// If we have a remainder, run a clean-up loop...
if ( m > 0 ) {
for ( i = 0; i < m; i++ ) {
y[ iy ] += alpha * x[ ix ];
ix += strideX;
iy += strideY;
}
}
if ( N < M ) {
return y;
}
for ( i = m; i < N; i += M ) {
y[ iy ] += alpha * x[ ix ];
y[ iy+1 ] += alpha * x[ ix+1 ];
y[ iy+2 ] += alpha * x[ ix+2 ];
y[ iy+3 ] += alpha * x[ ix+3 ];
ix += M;
iy += M;
}
return y;
}
for ( i = 0; i < N; i++ ) {
y[ iy ] += alpha * x[ ix ];
ix += strideX;
iy += strideY;
}
return y;
}
// EXPORTS //
module.exports = gaxpy;
|