/*
* Copyright (c) 2010, Lawrence Livermore National Security, LLC. Produced at
* the Lawrence Livermore National Laboratory. Written by Keith Stevens,
* kstevens@cs.ucla.edu OCEC-10-073 All rights reserved.
*
* This file is part of the C-Cat package and is covered under the terms and
* conditions therein.
*
* The S-Space package is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation and distributed hereunder to you.
*
* THIS SOFTWARE IS PROVIDED "AS IS" AND NO REPRESENTATIONS OR WARRANTIES,
* EXPRESS OR IMPLIED ARE MADE. BY WAY OF EXAMPLE, BUT NOT LIMITATION, WE MAKE
* NO REPRESENTATIONS OR WARRANTIES OF MERCHANT- ABILITY OR FITNESS FOR ANY
* PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED SOFTWARE OR DOCUMENTATION
* WILL NOT INFRINGE ANY THIRD PARTY PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER
* RIGHTS.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package edu.ucla.sspace.matrix;
import edu.ucla.sspace.vector.DoubleVector;
import edu.ucla.sspace.vector.ScaledSparseDoubleVector;
import edu.ucla.sspace.vector.SparseDoubleVector;
/**
* A decorator over {@link SparseMatrix}s. Each row can be scaled by some
* scalar constant in O(1) time by applying the scalar value for each row during
* all gets and sets to values in the row.
*
* @author Keith Stevens
*/
public class RowScaledSparseMatrix extends RowScaledMatrix
implements SparseMatrix, java.io.Serializable {
private static final long serialVersionUID = 1L;
/**
* The backing instance of the matrix.
*/
private final SparseMatrix m;
/**
* The {@link DoubleVector} for row scales.
*/
private final DoubleVector scales;
/**
* Creates a {@code RowScaledSparseMatrix} that provides scaled read only
* access to the provided {@code SparseMatrix} instance.
*/
public RowScaledSparseMatrix(SparseMatrix matrix, DoubleVector v) {
super(matrix, v);
this.m = matrix;
this.scales = v;
}
/**
* {@inheritDoc}
*/
public SparseDoubleVector getColumnVector(int row) {
throw new UnsupportedOperationException("cannot get row");
}
/**
* {@inheritDoc}
*/
public SparseDoubleVector getRowVector(int row) {
return new ScaledSparseDoubleVector(
m.getRowVector(row), scales.get(row));
}
}