package com.nr.test.test_chapter4;
import static com.nr.fi.GaussianWeights.gaujac;
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.UniVarRealValueFun;
import com.nr.sf.Bessjy;
public class Test_gaujac {
@Before
public void setUp() throws Exception {
}
@After
public void tearDown() throws Exception {
}
@Test
public void test() {
int i,j,N=8,M=20;
double alfa,beta,val,sbeps=1.e-11;
double[] y= new double[N],yy= new double[N],x= new double[M],w= new double[M];
boolean localflag, globalflag=false;
// Test gaujac
System.out.println("Testing gaujac");
Bessj0_gaujac bj0 = new Bessj0_gaujac();
Bessj1_gaujac bj1 = new Bessj1_gaujac();
for (i=0;i<N;i++) {
alfa=(double)(i)+1.0;
beta=(double)(N)-i;
gaujac(x,w,alfa,beta);
val=0.0;
for (j=0;j<M;j++) val += w[j]*bj1.funk(x[j]);
y[i]=val;
gaujac(x,w,alfa-1.0,beta);
val=0.0;
for (j=0;j<M;j++) val += w[j]*bj0.funk(x[j]);
yy[i]= -alfa*val;
gaujac(x,w,alfa,beta-1.0);
val=0.0;
for (j=0;j<M;j++) val += w[j]*bj0.funk(x[j]);
yy[i] += beta*val;
}
System.out.printf("gaujac: Maximum discrepancy = %f\n", maxel(vecsub(y,yy)));
localflag = maxel(vecsub(y,yy)) > sbeps;
globalflag = globalflag || localflag;
if (localflag) {
fail("*** gaujac: Failure to achieve accurate integral");
}
if (globalflag) System.out.println("Failed\n");
else System.out.println("Passed\n");
}
class Bessj0_gaujac implements UniVarRealValueFun{
public double funk (double x) {
Bessjy b = new Bessjy();
return(b.j0(x));
}
};
class Bessj1_gaujac implements UniVarRealValueFun{
public double funk (double x) {
Bessjy b = new Bessjy();
return(b.j1(x));
}
}
}