/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
package org.apache.mahout.math.hadoop;
import com.google.common.base.Function;
import com.google.common.collect.Iterators;
import org.apache.hadoop.conf.Configurable;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.mahout.common.Pair;
import org.apache.mahout.common.iterator.sequencefile.PathFilters;
import org.apache.mahout.common.iterator.sequencefile.PathType;
import org.apache.mahout.common.iterator.sequencefile.SequenceFileDirIterator;
import org.apache.mahout.math.CardinalityException;
import org.apache.mahout.math.MatrixSlice;
import org.apache.mahout.math.Vector;
import org.apache.mahout.math.VectorIterable;
import org.apache.mahout.math.VectorWritable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.Iterator;
/**
* DistributedRowMatrix is a FileSystem-backed VectorIterable in which the vectors live in a
* SequenceFile<WritableComparable,VectorWritable>, and distributed operations are executed as M/R passes on
* Hadoop. The usage is as follows: <p>
* <p>
* <pre>
* // the path must already contain an already created SequenceFile!
* DistributedRowMatrix m = new DistributedRowMatrix("path/to/vector/sequenceFile", "tmp/path", 10000000, 250000);
* m.setConf(new Configuration());
* // now if we want to multiply a vector by this matrix, it's dimension must equal the row dimension of this
* // matrix. If we want to timesSquared() a vector by this matrix, its dimension must equal the column dimension
* // of the matrix.
* Vector v = new DenseVector(250000);
* // now the following operation will be done via a M/R pass via Hadoop.
* Vector w = m.timesSquared(v);
* </pre>
*
*/
public class DistributedRowMatrix implements VectorIterable, Configurable {
public static final String KEEP_TEMP_FILES = "DistributedMatrix.keep.temp.files";
private static final Logger log = LoggerFactory.getLogger(DistributedRowMatrix.class);
private final Path inputPath;
private final Path outputTmpPath;
private Configuration conf;
private Path rowPath;
private Path outputTmpBasePath;
private final int numRows;
private final int numCols;
private boolean keepTempFiles;
public DistributedRowMatrix(Path inputPath,
Path outputTmpPath,
int numRows,
int numCols) {
this(inputPath, outputTmpPath, numRows, numCols, false);
}
public DistributedRowMatrix(Path inputPath,
Path outputTmpPath,
int numRows,
int numCols,
boolean keepTempFiles) {
this.inputPath = inputPath;
this.outputTmpPath = outputTmpPath;
this.numRows = numRows;
this.numCols = numCols;
this.keepTempFiles = keepTempFiles;
}
@Override
public Configuration getConf() {
return conf;
}
@Override
public void setConf(Configuration conf) {
this.conf = conf;
try {
rowPath = FileSystem.get(conf).makeQualified(inputPath);
outputTmpBasePath = FileSystem.get(conf).makeQualified(outputTmpPath);
keepTempFiles = conf.getBoolean(KEEP_TEMP_FILES, false);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
public Path getRowPath() {
return rowPath;
}
public Path getOutputTempPath() {
return outputTmpBasePath;
}
public void setOutputTempPathString(String outPathString) {
try {
outputTmpBasePath = FileSystem.get(conf).makeQualified(new Path(outPathString));
} catch (IOException ioe) {
log.warn("Unable to set outputBasePath to {}, leaving as {}",
outPathString, outputTmpBasePath);
}
}
@Override
public Iterator<MatrixSlice> iterateAll() {
try {
return Iterators.transform(
new SequenceFileDirIterator<IntWritable,VectorWritable>(new Path(rowPath, "*"),
PathType.GLOB,
PathFilters.logsCRCFilter(),
null,
true,
conf),
new Function<Pair<IntWritable,VectorWritable>,MatrixSlice>() {
@Override
public MatrixSlice apply(Pair<IntWritable, VectorWritable> from) {
return new MatrixSlice(from.getSecond().get(), from.getFirst().get());
}
});
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
@Override
public int numSlices() {
return numRows();
}
@Override
public int numRows() {
return numRows;
}
@Override
public int numCols() {
return numCols;
}
/**
* This implements matrix this.transpose().times(other)
* @param other a DistributedRowMatrix
* @return a DistributedRowMatrix containing the product
*/
public DistributedRowMatrix times(DistributedRowMatrix other) throws IOException {
if (numRows != other.numRows()) {
throw new CardinalityException(numRows, other.numRows());
}
Path outPath = new Path(outputTmpBasePath.getParent(), "productWith-" + (System.nanoTime() & 0xFF));
Configuration initialConf = getConf() == null ? new Configuration() : getConf();
Configuration conf =
MatrixMultiplicationJob.createMatrixMultiplyJobConf(initialConf,
rowPath,
other.rowPath,
outPath,
other.numCols);
JobClient.runJob(new JobConf(conf));
DistributedRowMatrix out = new DistributedRowMatrix(outPath, outputTmpPath, numCols, other.numCols());
out.setConf(conf);
return out;
}
public DistributedRowMatrix transpose() throws IOException {
Path outputPath = new Path(rowPath.getParent(), "transpose-" + (System.nanoTime() & 0xFF));
Configuration initialConf = getConf() == null ? new Configuration() : getConf();
Configuration conf = TransposeJob.buildTransposeJobConf(initialConf, rowPath, outputPath, numRows);
JobClient.runJob(new JobConf(conf));
DistributedRowMatrix m = new DistributedRowMatrix(outputPath, outputTmpPath, numCols, numRows);
m.setConf(this.conf);
return m;
}
@Override
public Vector times(Vector v) {
try {
Configuration initialConf = getConf() == null ? new Configuration() : getConf();
Path outputVectorTmpPath = new Path(outputTmpBasePath,
new Path(Long.toString(System.nanoTime())));
Configuration conf =
TimesSquaredJob.createTimesJobConf(initialConf,
v,
numRows,
rowPath,
outputVectorTmpPath);
JobClient.runJob(new JobConf(conf));
Vector result = TimesSquaredJob.retrieveTimesSquaredOutputVector(conf);
if (!keepTempFiles) {
FileSystem fs = outputVectorTmpPath.getFileSystem(conf);
fs.delete(outputVectorTmpPath, true);
}
return result;
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
@Override
public Vector timesSquared(Vector v) {
try {
Configuration initialConf = getConf() == null ? new Configuration() : getConf();
Path outputVectorTmpPath = new Path(outputTmpBasePath,
new Path(Long.toString(System.nanoTime())));
Configuration conf =
TimesSquaredJob.createTimesSquaredJobConf(initialConf,
v,
rowPath,
outputVectorTmpPath);
JobClient.runJob(new JobConf(conf));
Vector result = TimesSquaredJob.retrieveTimesSquaredOutputVector(conf);
if (!keepTempFiles) {
FileSystem fs = outputVectorTmpPath.getFileSystem(conf);
fs.delete(outputVectorTmpPath, true);
}
return result;
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
@Override
public Iterator<MatrixSlice> iterator() {
return iterateAll();
}
public static class MatrixEntryWritable implements WritableComparable<MatrixEntryWritable> {
private int row;
private int col;
private double val;
public int getRow() {
return row;
}
public void setRow(int row) {
this.row = row;
}
public int getCol() {
return col;
}
public void setCol(int col) {
this.col = col;
}
public double getVal() {
return val;
}
public void setVal(double val) {
this.val = val;
}
@Override
public int compareTo(MatrixEntryWritable o) {
if (row > o.row) {
return 1;
} else if (row < o.row) {
return -1;
} else {
if (col > o.col) {
return 1;
} else if (col < o.col) {
return -1;
} else {
return 0;
}
}
}
@Override
public boolean equals(Object o) {
if (!(o instanceof MatrixEntryWritable)) {
return false;
}
MatrixEntryWritable other = (MatrixEntryWritable) o;
return row == other.row && col == other.col;
}
@Override
public int hashCode() {
return row + 31 * col;
}
@Override
public void write(DataOutput out) throws IOException {
out.writeInt(row);
out.writeInt(col);
out.writeDouble(val);
}
@Override
public void readFields(DataInput in) throws IOException {
row = in.readInt();
col = in.readInt();
val = in.readDouble();
}
@Override
public String toString() {
return "(" + row + ',' + col + "):" + val;
}
}
}