1 //****************************************************************************** 2 // 3 // File: FloatMatrixBuf.java 4 // Package: edu.rit.mp.buf 5 // Unit: Class edu.rit.mp.buf.FloatMatrixBuf 6 // 7 // This Java source file is copyright (C) 2009 by Alan Kaminsky. All rights 8 // reserved. For further information, contact the author, Alan Kaminsky, at 9 // ark@cs.rit.edu. 10 // 11 // This Java source file is part of the Parallel Java Library ("PJ"). PJ is free 12 // software; you can redistribute it and/or modify it under the terms of the GNU 13 // General Public License as published by the Free Software Foundation; either 14 // version 3 of the License, or (at your option) any later version. 15 // 16 // PJ is distributed in the hope that it will be useful, but WITHOUT ANY 17 // WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR 18 // A PARTICULAR PURPOSE. See the GNU General Public License for more details. 19 // 20 // Linking this library statically or dynamically with other modules is making a 21 // combined work based on this library. Thus, the terms and conditions of the GNU 22 // General Public License cover the whole combination. 23 // 24 // As a special exception, the copyright holders of this library give you 25 // permission to link this library with independent modules to produce an 26 // executable, regardless of the license terms of these independent modules, and 27 // to copy and distribute the resulting executable under terms of your choice, 28 // provided that you also meet, for each linked independent module, the terms 29 // and conditions of the license of that module. An independent module is a module 30 // which is not derived from or based on this library. If you modify this library, 31 // you may extend this exception to your version of the library, but you are not 32 // obligated to do so. If you do not wish to do so, delete this exception 33 // statement from your version. 34 // 35 // A copy of the GNU General Public License is provided in the file gpl.txt. You 36 // may also obtain a copy of the GNU General Public License on the World Wide 37 // Web at http://www.gnu.org/licenses/gpl.html. 38 // 39 //****************************************************************************** 40 package edu.rit.mp.buf; 41 42 import java.nio.ByteBuffer; 43 import java.nio.FloatBuffer; 44 45 import edu.rit.mp.Buf; 46 import edu.rit.mp.FloatBuf; 47 import edu.rit.pj.reduction.FloatOp; 48 import edu.rit.pj.reduction.Op; 49 import edu.rit.util.Arrays; 50 import edu.rit.util.Range; 51 52 /** 53 * Class FloatMatrixBuf provides a buffer for a matrix of float items sent or 54 * received using the Message Protocol (MP). The matrix row and column strides 55 * may be 1 or greater than 1. While an instance of class FloatMatrixBuf may be 56 * constructed directly, normally you will use a factory method in class 57 * {@linkplain edu.rit.mp.FloatBuf FloatBuf}. See that class for further 58 * information. 59 * 60 * @author Alan Kaminsky 61 * @version 05-Apr-2009 62 */ 63 public class FloatMatrixBuf 64 extends FloatBuf { 65 66 // Hidden data members. 67 float[][] myMatrix; 68 Range myRowRange; 69 Range myColRange; 70 int myLowerRow; 71 int myRowCount; 72 int myRowStride; 73 int myLowerCol; 74 int myColCount; 75 int myColStride; 76 77 // Exported constructors. 78 /** 79 * Construct a new float matrix buffer. It is assumed that the rows and 80 * columns of <code>theMatrix</code> are allocated and that each row of 81 * <code>theMatrix</code> has the same number of columns. 82 * 83 * @param theMatrix Matrix. 84 * @param theRowRange Range of rows to include. 85 * @param theColRange Range of columns to include. 86 */ 87 public FloatMatrixBuf(float[][] theMatrix, 88 Range theRowRange, 89 Range theColRange) { 90 super(theRowRange.length() * theColRange.length()); 91 myMatrix = theMatrix; 92 myRowRange = theRowRange; 93 myColRange = theColRange; 94 myLowerRow = theRowRange.lb(); 95 myRowCount = theRowRange.length(); 96 myRowStride = theRowRange.stride(); 97 myLowerCol = theColRange.lb(); 98 myColCount = theColRange.length(); 99 myColStride = theColRange.stride(); 100 } 101 102 // Exported operations. 103 /** 104 * {@inheritDoc} 105 * 106 * Obtain the given item from this buffer. 107 * <P> 108 * The <code>get()</code> method must not block the calling thread; if it does, 109 * all message I/O in MP will be blocked. 110 */ 111 public float get(int i) { 112 return myMatrix[i2r(i) * myRowStride + myLowerRow][i2c(i) * myColStride + myLowerCol]; 113 } 114 115 /** 116 * {@inheritDoc} 117 * 118 * Store the given item in this buffer. 119 * <P> 120 * The <code>put()</code> method must not block the calling thread; if it does, 121 * all message I/O in MP will be blocked. 122 */ 123 public void put(int i, 124 float item) { 125 myMatrix[i2r(i) * myRowStride + myLowerRow][i2c(i) * myColStride + myLowerCol] = item; 126 } 127 128 /** 129 * {@inheritDoc} 130 * 131 * Copy items from the given buffer to this buffer. The number of items 132 * copied is this buffer's length or <code>theSrc</code>'s length, whichever is 133 * smaller. If <code>theSrc</code> is this buffer, the <code>copy()</code> method 134 * does nothing. 135 * @exception ClassCastException (unchecked exception) Thrown if 136 * <code>theSrc</code>'s item data type is not the same as this buffer's item 137 * data type. 138 */ 139 public void copy(Buf theSrc) { 140 if (theSrc == this) { 141 } else if (theSrc instanceof FloatMatrixBuf) { 142 FloatMatrixBuf src = (FloatMatrixBuf) theSrc; 143 Arrays.copy(src.myMatrix, src.myRowRange, src.myColRange, 144 this.myMatrix, this.myRowRange, this.myColRange); 145 } else { 146 FloatBuf.defaultCopy((FloatBuf) theSrc, this); 147 } 148 } 149 150 /** 151 * {@inheritDoc} 152 * 153 * Create a buffer for performing parallel reduction using the given binary 154 * operation. The results of the reduction are placed into this buffer. 155 * @exception ClassCastException (unchecked exception) Thrown if this 156 * buffer's element data type and the given binary operation's argument data 157 * type are not the same. 158 */ 159 public Buf getReductionBuf(Op op) { 160 return new FloatMatrixReductionBuf(myMatrix, myRowRange, myColRange, (FloatOp) op); 161 } 162 163 // Hidden operations. 164 /** 165 * {@inheritDoc} 166 * 167 * Send as many items as possible from this buffer to the given byte buffer. 168 * <P> 169 * The <code>sendItems()</code> method must not block the calling thread; if it 170 * does, all message I/O in MP will be blocked. 171 */ 172 protected int sendItems(int i, 173 ByteBuffer buffer) { 174 FloatBuffer floatbuffer = buffer.asFloatBuffer(); 175 int n = 0; 176 int r = i2r(i); 177 int row = r * myRowStride + myLowerRow; 178 int c = i2c(i); 179 int col = c * myColStride + myLowerCol; 180 int ncols = Math.min(myColCount - c, floatbuffer.remaining()); 181 while (r < myRowCount && ncols > 0) { 182 float[] myMatrix_row = myMatrix[row]; 183 while (c < ncols) { 184 floatbuffer.put(myMatrix_row[col]); 185 ++c; 186 col += myColStride; 187 } 188 n += ncols; 189 ++r; 190 row += myRowStride; 191 c = 0; 192 col = myLowerCol; 193 ncols = Math.min(myColCount, floatbuffer.remaining()); 194 } 195 buffer.position(buffer.position() + 4 * n); 196 return n; 197 } 198 199 /** 200 * {@inheritDoc} 201 * 202 * Receive as many items as possible from the given byte buffer to this 203 * buffer. 204 * <P> 205 * The <code>receiveItems()</code> method must not block the calling thread; if 206 * it does, all message I/O in MP will be blocked. 207 */ 208 protected int receiveItems(int i, 209 int num, 210 ByteBuffer buffer) { 211 FloatBuffer floatbuffer = buffer.asFloatBuffer(); 212 num = Math.min(num, floatbuffer.remaining()); 213 int n = 0; 214 int r = i2r(i); 215 int row = r * myRowStride + myLowerRow; 216 int c = i2c(i); 217 int col = c * myColStride + myLowerCol; 218 int ncols = Math.min(myColCount - c, num); 219 while (r < myRowCount && ncols > 0) { 220 float[] myMatrix_row = myMatrix[row]; 221 for (c = 0; c < ncols; ++c) { 222 myMatrix_row[col] = floatbuffer.get(); 223 col += myColStride; 224 } 225 num -= ncols; 226 n += ncols; 227 ++r; 228 row += myRowStride; 229 col = myLowerCol; 230 ncols = Math.min(myColCount, num); 231 } 232 buffer.position(buffer.position() + 4 * n); 233 return n; 234 } 235 236 /** 237 * Convert the given buffer index to a row index. 238 */ 239 int i2r(int i) { 240 return myColCount == 0 ? i : i / myColCount; 241 } 242 243 /** 244 * Convert the given buffer index to a column index. 245 */ 246 int i2c(int i) { 247 return myColCount == 0 ? 0 : i % myColCount; 248 } 249 250 }