package com.nr.test.test_chapter9;
import static com.nr.root.Roots.zbrac;
import static org.junit.Assert.fail;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.netlib.util.doubleW;
import com.nr.UniVarRealValueFun;
import com.nr.sf.Bessjy;
public class Test_zbrac {
@Before
public void setUp() throws Exception {
}
@After
public void tearDown() throws Exception {
}
@Test
public void test() {
boolean success;
int i,j,N=16,M=50;
doubleW x1=new doubleW(0),x2=new doubleW(0);
double y[]={2.404825557695773,5.520078110286311,8.653727912911013,
1.179153443901428e1,1.493091770848779e1,1.807106396791092e1,
2.121163662987926e1,2.435247153074930e1,2.749347913204025e1,
3.063460646843198e1,3.377582021357357e1,3.691709835366405e1,
4.005842576462825e1,4.319979171317673e1,4.634118837166182e1,
4.948260989739782e1};
boolean localflag, globalflag=false;
// Test zbrac
System.out.println("Testing zbrac");
Func_zbrac fx = new Func_zbrac();
for (i=1;i<M;i++) {
x1.val=(double)(i);
x2.val=(double)(i+1);
success=zbrac(fx,x1,x2);
localflag = !success;
globalflag = globalflag || localflag;
if (localflag) {
fail("*** zbrac: Failed to find a bracket with one of the starting intervals.");
}
localflag = localflag || (fx.funk(x1.val)*fx.funk(x2.val) >= 0.0);
globalflag = globalflag || localflag;
if (localflag) {
fail("*** zbrac: An identified bracketing interval does not actually bracket a root.");
}
for (j=0;j<N;j++)
localflag=localflag || (y[j] > x1.val) && (y[j] < x2.val);
localflag = !localflag;
globalflag = globalflag || localflag;
if (localflag) {
fail("*** zbrac: No known root of bessj0 falls witning one of the identified brackets.");
}
}
if (globalflag) System.out.println("Failed\n");
else System.out.println("Passed\n");
}
class Func_zbrac implements UniVarRealValueFun{
Bessjy b =new Bessjy();
public double funk (final double x) {
return b.j0(x);
}
}
}