/*
* Copyright (c) 2009-2012, Peter Abeles. All Rights Reserved.
*
* This file is part of Efficient Java Matrix Library (EJML).
*
* EJML 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 3
* of the License, or (at your option) any later version.
*
* EJML 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 EJML. If not, see <http://www.gnu.org/licenses/>.
*/
package org.ejml.alg.dense.decomposition.hessenberg;
import org.ejml.data.DenseMatrix64F;
import org.ejml.ops.MatrixFeatures;
import org.ejml.ops.RandomMatrices;
import org.ejml.simple.SimpleMatrix;
import org.junit.Test;
import java.util.Random;
import static org.ejml.alg.dense.decomposition.CheckDecompositionInterface.safeDecomposition;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
/**
* @author Peter Abeles
*/
public abstract class StandardTridiagonalTests {
protected Random rand = new Random(2344);
protected abstract TridiagonalSimilarDecomposition<DenseMatrix64F> createDecomposition();
@Test
public void fullTest() {
for( int width = 1; width < 20; width += 2 ) {
SimpleMatrix A = SimpleMatrix.wrap(RandomMatrices.createSymmetric(width,-1,1,rand));
TridiagonalSimilarDecomposition<DenseMatrix64F> alg = createDecomposition();
assertTrue(safeDecomposition(alg,A.getMatrix()));
// test the results using the decomposition's definition
SimpleMatrix Q = SimpleMatrix.wrap(alg.getQ(null,false));
SimpleMatrix T = SimpleMatrix.wrap(alg.getT(null));
SimpleMatrix A_found = Q.mult(T).mult(Q.transpose());
assertTrue("width = "+width,MatrixFeatures.isIdentical(A.getMatrix(),A_found.getMatrix(),1e-8));
}
}
@Test
public void getDiagonal() {
for( int width = 1; width < 20; width += 2 ) {
DenseMatrix64F A = RandomMatrices.createSymmetric(width,-1,1,rand);
TridiagonalSimilarDecomposition<DenseMatrix64F> alg = createDecomposition();
assertTrue(safeDecomposition(alg,A));
DenseMatrix64F T = alg.getT(null);
double diag[] = new double[width];
double off[] = new double[width];
alg.getDiagonal(diag,off);
assertEquals(T.get(0,0),diag[0],1e-8);
for( int i = 1; i < width; i++ ) {
assertEquals(T.get(i,i),diag[i],1e-8);
assertEquals(T.get(i-1,i),off[i-1],1e-8);
}
}
}
@Test
public void transposeFlagForQ() {
for( int width = 1; width < 20; width += 2 ) {
DenseMatrix64F A = RandomMatrices.createSymmetric(width,-1,1,rand);
TridiagonalSimilarDecomposition<DenseMatrix64F> alg = createDecomposition();
assertTrue(safeDecomposition(alg,A));
DenseMatrix64F Q = alg.getQ(null,false);
DenseMatrix64F Q_t = alg.getQ(null,true);
for( int i = 0; i < Q.numRows; i++ ) {
for( int j = 0; j < Q.numCols; j++ ) {
assertEquals(Q.get(i,j),Q_t.get(j,i),1e-8);
}
}
}
}
}