package com.nr.test.test_chapter11;
import static com.nr.test.NRTestUtil.matmul;
import static com.nr.test.NRTestUtil.maxel;
import static com.nr.test.NRTestUtil.vecsub;
import static org.junit.Assert.fail;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import com.nr.eig.Jacobi;
import com.nr.ran.Ran;
public class Test_Jacobi {
@Before
public void setUp() throws Exception {
}
@After
public void tearDown() throws Exception {
}
@Test
public void test() {
int i,j,N=10;
double sbeps=3.e-15;
double[] vec=new double[N],res=new double[N];
double[][] a = new double[N][N];
boolean localflag=false, globalflag=false;
// Test Jacobi
System.out.println("Testing Jacobi");
Ran myran = new Ran(17);
for (i=0;i<N;i++) {
a[i][i]=myran.doub();
for (j=0;j<i;j++) {
a[i][j]=myran.doub();
a[j][i]=a[i][j];
}
}
Jacobi jac = new Jacobi(a);
// test eigenvector/eigenvalue pairs
for (i=0;i<N;i++) { // for each eigenvector
for (j=0;j<N;j++) vec[j]=jac.v[j][i];
res=matmul(a,vec);
for (j=0;j<N;j++) vec[j] *= jac.d[i];
localflag = localflag || (maxel(vecsub(res,vec)) > sbeps);
}
globalflag = globalflag || localflag;
if (localflag) {
fail("*** Jacobi: Matrix times eigenvector was not the same as lambda*eigenvector");
}
localflag=false;
// test the sorting of the eigenvalues by eigsrt()
for (i=1;i<N;i++)
localflag = localflag || (jac.d[i] > jac.d[i-1]);
globalflag = globalflag || localflag;
if (localflag) {
fail("*** Jacobi: Eigenvalues not sorted in high-to-low order");
}
if (globalflag) System.out.println("Failed\n");
else System.out.println("Passed\n");
}
}