no.uib.cipr.matrix.distributed.DistMatrix Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of mtj Show documentation
Show all versions of mtj Show documentation
A comprehensive collection of matrix data structures, linear solvers, least squares methods,
eigenvalue, and singular value decompositions.
/*
* Copyright (C) 2003-2006 Bjørn-Ove Heimsund
*
* This file is part of MTJ.
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by the
* Free Software Foundation; either version 2.1 of the License, or (at your
* option) any later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package no.uib.cipr.matrix.distributed;
import java.util.Arrays;
import java.util.Iterator;
import no.uib.cipr.matrix.AbstractMatrix;
import no.uib.cipr.matrix.DenseVector;
import no.uib.cipr.matrix.Matrix;
import no.uib.cipr.matrix.MatrixEntry;
import no.uib.cipr.matrix.Vector;
import no.uib.cipr.matrix.distributed.SuperIterator.SuperIteratorEntry;
/**
* Distributed memory matrix
*
* @deprecated the no.uib.cipr.matrix.distributed
package has been deprecated because
* of a number of hard to fix concurrency bugs. It is distributed only for backwards compatibility,
* but is not recommended. The utility of this package is questionable, as it does not allow
* distribution of computation between JVMs or across a network. For many people, distributed
* computing of multiple matrices can be achieved at a user-level through the
* JPPF Framework.
* Users who need to deal with few very large matrices may wish to implement their own storage classes
* and solvers using JPPF, but this will not be supported directly in matrix-toolkits-java.
*/
@Deprecated
abstract class DistMatrix extends AbstractMatrix {
/**
* Communicator in use
*/
final Communicator comm;
/**
* Block diagonal part
*/
final Matrix A;
/**
* Off-diagonal part
*/
final Matrix B;
/**
* Offsets into the local matrix
*/
final int[] n, m;
/**
* Rank and size of the communicator
*/
final int rank, size;
/**
* Local vector caches, for scatter/gather operations. The first with size
* equal numRows, the other of numColumns size
*/
final Vector locR, locC;
/**
* Scatters global vectors into local, and the other way around
*/
final VectorScatter scatter;
/**
* Constructor for DistMatrix
*/
public DistMatrix(int numRows, int numColumns, Communicator comm, Matrix A,
Matrix B) {
super(numRows, numColumns);
this.comm = comm;
this.A = A;
this.B = B;
locR = new DenseVector(numRows);
locC = new DenseVector(numColumns);
rank = comm.rank();
size = comm.size();
n = new int[size + 1];
m = new int[size + 1];
// Find out the sizes of all the parts of the distributed vector
int[] send = new int[] { A.numRows(), A.numColumns() };
int[][] recv = new int[size][2];
comm.allGather(send, recv);
for (int i = 0; i < size; ++i) {
n[i + 1] = n[i] + recv[i][0]; // rows
m[i + 1] = m[i] + recv[i][1]; // columns
}
if (n[size] != numRows)
throw new IllegalArgumentException("Sum of local row sizes ("
+ n[size] + ") do not match the global row size ("
+ numRows + ")");
if (m[size] != numColumns)
throw new IllegalArgumentException("Sum of local column sizes ("
+ m[size] + ") do not match the global column size ("
+ numColumns + ")");
scatter = scatterSetup();
}
/**
* Sets up vector scatter for matrix/vector products. Collective operation
*/
private VectorScatter scatterSetup() {
// Get all the indices needing communication
int[] ind = getCommIndices();
Arrays.sort(ind);
// Find who owns what
int[] N = getDelimiter();
// Then get the number of entries to recieve and their indices
int[][] recv = new int[size][1];
int[][] recvI = new int[size][];
for (int k = 0, i = 0; k < size; ++k) {
// Number of entries
for (int l = 0, I = i; I < ind.length && ind[I] < N[k + 1]; ++I, ++l)
recv[k][0]++;
// The indices
recvI[k] = new int[recv[k][0]];
for (int l = 0, I = i; I < ind.length && ind[I] < N[k + 1]; ++I, ++l)
recvI[k][l] = ind[I];
i += recv[k][0];
}
// Get the number of entries to send
int[][] send = new int[size][1];
comm.allToAll(recv, send);
// Then the indices to send
int[][] sendI = new int[size][];
for (int i = 0; i < size; ++i)
sendI[i] = new int[send[i][0]];
// Send what we need to recieve, and in return, get what the other
// threads need
comm.allToAll(recvI, sendI);
// Create vector scatter object
return new VectorScatter(comm, sendI, recvI);
}
/**
* Returns delimiters
*/
abstract int[] getDelimiter();
/**
* Returns indices needing communication (off the block diagonal)
*/
abstract int[] getCommIndices();
/**
* Returns which rows are owned by which ranks. The current rank owns the
* rows n[comm.rank()]
(inclusive) to
* n[comm.rank()+1]
(exclusive)
*/
public int[] getRowOwnerships() {
return n;
}
/**
* Returns which columns are owned by which ranks. The current rank owns the
* columns m[comm.rank()]
(inclusive) to
* m[comm.rank()+1]
(exclusive)
*/
public int[] getColumnOwnerships() {
return m;
}
/**
* Returns the diagonal block matrix
*/
public Matrix getBlock() {
return A;
}
/**
* Returns the off-diagonal matrix
*/
public Matrix getOff() {
return B;
}
@Override
public DistMatrix zero() {
A.zero();
B.zero();
return this;
}
@Override
protected double max() {
// Compute local norms
double normA = A.norm(Norm.Maxvalue), normB = B.norm(Norm.Maxvalue);
// Find global maximum
double[] recv = new double[2];
comm.allReduce(new double[] { normA, normB }, recv, Reductions.max());
return recv[0] + recv[1];
}
@Override
protected double normF() {
// Compute local norms
double normA = A.norm(Norm.Frobenius), normB = B.norm(Norm.Frobenius);
normA *= normA;
normB *= normB;
// Sum the global norms
double[] recv = new double[2];
comm.allReduce(new double[] { normA, normB }, recv, Reductions.sum());
return Math.sqrt(recv[0] + recv[1]);
}
/**
* Returns true if the insertion indices are local to this rank, and no
* communication is required afterwards. However, you still need to call
* flushAssembly
to set up things like matrix/vector
* multiplication
*/
public abstract boolean local(int row, int column);
boolean inA(int row, int column) {
return row >= n[rank] && row < n[rank + 1] && column >= m[rank]
&& column < m[rank + 1];
}
@Override
public Matrix rank1(double alpha, Vector x, Vector y) {
throw new UnsupportedOperationException();
}
@Override
public Matrix rank2(double alpha, Vector x, Vector y) {
throw new UnsupportedOperationException();
}
/**
* Gets the communicator associated with this matrix
*/
public Communicator getCommunicator() {
return comm;
}
/**
* Iterator for a distributed memory matrix
*/
class DistMatrixIterator implements Iterator {
/**
* Iterates over each column vector
*/
private SuperIterator iterator;
/**
* Entry returned
*/
private DistMatrixEntry entry;
private int rowAOffset, columnAOffset, rowBOffset, columnBOffset;
public DistMatrixIterator(int rowAOffset, int columnAOffset,
int rowBOffset, int columnBOffset) {
this.rowAOffset = rowAOffset;
this.rowBOffset = rowBOffset;
this.columnAOffset = columnAOffset;
this.columnBOffset = columnBOffset;
iterator = new SuperIterator(Arrays.asList(A,
B));
entry = new DistMatrixEntry();
}
public boolean hasNext() {
return iterator.hasNext();
}
public MatrixEntry next() {
SuperIteratorEntry se = iterator.next();
if (se.index() == 0)
// Block diagonal part
entry.update(rowAOffset, columnAOffset, se.get());
else
// Off diagonal block
entry.update(rowBOffset, columnBOffset, se.get());
return entry;
}
public void remove() {
iterator.remove();
}
}
/**
* Entry of a distributed memory matrix
*/
private static class DistMatrixEntry implements MatrixEntry {
private int row, column;
private MatrixEntry entry;
public void update(int rowOffset, int columnOffset, MatrixEntry entry) {
row = rowOffset + entry.row();
column = columnOffset + entry.column();
this.entry = entry;
}
public int row() {
return row;
}
public int column() {
return column;
}
public double get() {
return entry.get();
}
public void set(double value) {
entry.set(value);
}
}
}