6d_accessors.js (6171B)
1 /** 2 * @license Apache-2.0 3 * 4 * Copyright (c) 2021 The Stdlib Authors. 5 * 6 * Licensed under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 /* eslint-disable max-depth */ 20 21 'use strict'; 22 23 // MAIN // 24 25 /** 26 * Applies a unary callback to elements in a six-dimensional input ndarray and assigns results to elements in an equivalently shaped output ndarray. 27 * 28 * @private 29 * @param {Object} x - object containing input ndarray meta data 30 * @param {string} x.dtype - data type 31 * @param {Collection} x.data - data buffer 32 * @param {NonNegativeIntegerArray} x.shape - dimensions 33 * @param {IntegerArray} x.strides - stride lengths 34 * @param {NonNegativeInteger} x.offset - index offset 35 * @param {string} x.order - specifies whether `x` is row-major (C-style) or column-major (Fortran-style) 36 * @param {Function} x.getter - callback for accessing `x` data buffer elements 37 * @param {Object} y - object containing output ndarray meta data 38 * @param {string} y.dtype - data type 39 * @param {Collection} y.data - data buffer 40 * @param {NonNegativeIntegerArray} y.shape - dimensions 41 * @param {IntegerArray} y.strides - stride lengths 42 * @param {NonNegativeInteger} y.offset - index offset 43 * @param {string} y.order - specifies whether `y` is row-major (C-style) or column-major (Fortran-style) 44 * @param {Function} y.setter - callback for setting `y` data buffer elements 45 * @param {Callback} fcn - unary callback 46 * @returns {void} 47 * 48 * @example 49 * var Complex64Array = require( '@stdlib/array/complex64' ); 50 * var Complex64 = require( '@stdlib/complex/float32' ); 51 * var real = require( '@stdlib/complex/real' ); 52 * var imag = require( '@stdlib/complex/imag' ); 53 * 54 * function scale( z ) { 55 * return new Complex64( real(z)*10.0, imag(z)*10.0 ); 56 * } 57 * 58 * // Create data buffers: 59 * var xbuf = new Complex64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] ); 60 * var ybuf = new Complex64Array( 4 ); 61 * 62 * // Define the shape of the input and output arrays: 63 * var shape = [ 1, 1, 1, 1, 2, 2 ]; 64 * 65 * // Define the array strides: 66 * var sx = [ 2, 2, 2, 2, 2, 1 ]; 67 * var sy = [ 2, 2, 2, 2, 2, 1 ]; 68 * 69 * // Define the index offsets: 70 * var ox = 0; 71 * var oy = 0; 72 * 73 * // Define getters and setters: 74 * function getter( buf, idx ) { 75 * return buf.get( idx ); 76 * } 77 * 78 * function setter( buf, idx, value ) { 79 * buf.set( value, idx ); 80 * } 81 * 82 * // Create the input and output ndarray-like objects: 83 * var x = { 84 * 'dtype': 'complex64', 85 * 'data': xbuf, 86 * 'shape': shape, 87 * 'strides': sx, 88 * 'offset': ox, 89 * 'order': 'row-major', 90 * 'getter': getter 91 * }; 92 * var y = { 93 * 'dtype': 'complex64', 94 * 'data': ybuf, 95 * 'shape': shape, 96 * 'strides': sy, 97 * 'offset': oy, 98 * 'order': 'row-major', 99 * 'setter': setter 100 * }; 101 * 102 * // Apply the unary function: 103 * unary6d( x, y, scale ); 104 * 105 * var v = y.data.get( 0 ); 106 * 107 * var re = real( v ); 108 * // returns 10.0 109 * 110 * var im = imag( v ); 111 * // returns 20.0 112 */ 113 function unary6d( x, y, fcn ) { 114 var xbuf; 115 var ybuf; 116 var get; 117 var set; 118 var dx0; 119 var dx1; 120 var dx2; 121 var dx3; 122 var dx4; 123 var dx5; 124 var dy0; 125 var dy1; 126 var dy2; 127 var dy3; 128 var dy4; 129 var dy5; 130 var sh; 131 var S0; 132 var S1; 133 var S2; 134 var S3; 135 var S4; 136 var S5; 137 var sx; 138 var sy; 139 var ix; 140 var iy; 141 var i0; 142 var i1; 143 var i2; 144 var i3; 145 var i4; 146 var i5; 147 148 // Note on variable naming convention: S#, dx#, dy#, i# where # corresponds to the loop number, with `0` being the innermost loop... 149 150 // Extract loop variables for purposes of loop interchange: dimensions and loop offset (pointer) increments... 151 sh = x.shape; 152 sx = x.strides; 153 sy = y.strides; 154 if ( x.order === 'row-major' ) { 155 // For row-major ndarrays, the last dimensions have the fastest changing indices... 156 S0 = sh[ 5 ]; 157 S1 = sh[ 4 ]; 158 S2 = sh[ 3 ]; 159 S3 = sh[ 2 ]; 160 S4 = sh[ 1 ]; 161 S5 = sh[ 0 ]; 162 dx0 = sx[ 5 ]; // offset increment for innermost loop 163 dx1 = sx[ 4 ] - ( S0*sx[5] ); 164 dx2 = sx[ 3 ] - ( S1*sx[4] ); 165 dx3 = sx[ 2 ] - ( S2*sx[3] ); 166 dx4 = sx[ 1 ] - ( S3*sx[2] ); 167 dx5 = sx[ 0 ] - ( S4*sx[1] ); // offset increment for outermost loop 168 dy0 = sy[ 5 ]; 169 dy1 = sy[ 4 ] - ( S0*sy[5] ); 170 dy2 = sy[ 3 ] - ( S1*sy[4] ); 171 dy3 = sy[ 2 ] - ( S2*sy[3] ); 172 dy4 = sy[ 1 ] - ( S3*sy[2] ); 173 dy5 = sy[ 0 ] - ( S4*sy[1] ); 174 } else { // order === 'column-major' 175 // For column-major ndarrays, the first dimensions have the fastest changing indices... 176 S0 = sh[ 0 ]; 177 S1 = sh[ 1 ]; 178 S2 = sh[ 2 ]; 179 S3 = sh[ 3 ]; 180 S4 = sh[ 4 ]; 181 S5 = sh[ 5 ]; 182 dx0 = sx[ 0 ]; // offset increment for innermost loop 183 dx1 = sx[ 1 ] - ( S0*sx[0] ); 184 dx2 = sx[ 2 ] - ( S1*sx[1] ); 185 dx3 = sx[ 3 ] - ( S2*sx[2] ); 186 dx4 = sx[ 4 ] - ( S3*sx[3] ); 187 dx5 = sx[ 5 ] - ( S4*sx[4] ); // offset increment for outermost loop 188 dy0 = sy[ 0 ]; 189 dy1 = sy[ 1 ] - ( S0*sy[0] ); 190 dy2 = sy[ 2 ] - ( S1*sy[1] ); 191 dy3 = sy[ 3 ] - ( S2*sy[2] ); 192 dy4 = sy[ 4 ] - ( S3*sy[3] ); 193 dy5 = sy[ 5 ] - ( S4*sy[4] ); 194 } 195 // Set the pointers to the first indexed elements in the respective ndarrays... 196 ix = x.offset; 197 iy = y.offset; 198 199 // Cache references to the input and output ndarray buffers... 200 xbuf = x.data; 201 ybuf = y.data; 202 203 // Cache accessors: 204 get = x.getter; 205 set = y.setter; 206 207 // Iterate over the ndarray dimensions... 208 for ( i5 = 0; i5 < S5; i5++ ) { 209 for ( i4 = 0; i4 < S4; i4++ ) { 210 for ( i3 = 0; i3 < S3; i3++ ) { 211 for ( i2 = 0; i2 < S2; i2++ ) { 212 for ( i1 = 0; i1 < S1; i1++ ) { 213 for ( i0 = 0; i0 < S0; i0++ ) { 214 set( ybuf, iy, fcn( get( xbuf, ix ) ) ); 215 ix += dx0; 216 iy += dy0; 217 } 218 ix += dx1; 219 iy += dy1; 220 } 221 ix += dx2; 222 iy += dy2; 223 } 224 ix += dx3; 225 iy += dy3; 226 } 227 ix += dx4; 228 iy += dy4; 229 } 230 ix += dx5; 231 iy += dy5; 232 } 233 } 234 235 236 // EXPORTS // 237 238 module.exports = unary6d;