package com.nr.test.test_chapter9;
import static com.nr.root.Roots.laguer;
import static com.nr.test.NRTestUtil.maxel;
import static org.junit.Assert.fail;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.netlib.util.intW;
import com.nr.Complex;
import com.nr.ran.Ran;
public class Test_laguer {
@Before
public void setUp() throws Exception {
}
@After
public void tearDown() throws Exception {
}
@Test
public void test() {
intW its = new intW(0);
int i,M=5,N=20;
double sbeps=1.e-14;
Complex x = new Complex(),re1 = new Complex(1.0,0.0),im1=new Complex(0.0,1.0);
Complex a[]={
re1.mul(2.0).add(im1),
im1.mul(2.0),
re1.mul(3.0).add(im1),
re1.add(im1.mul(2.0)),
re1.sub(im1),
new Complex(1.0)
};
Complex[] aa = new Complex[M+1];System.arraycopy(a, 0, aa, 0 , M+1);
double[] dy = new double[N];
boolean localflag, globalflag=false;
// Test laguer
System.out.println("Testing laguer");
// Roots of polynomial x^5+(1-i)x^4+(1+2i)x^3+(3+i)x^2+(2i)x+(2+i)"
// Roots are x=i, x=-i, x=sqrt(2i), x=-i*sqrt(2i), x=(i-1)
Ran myran =new Ran(17);
for (i=0;i<N;i++) {
x=new Complex(-2.0+4.0*myran.doub(),-2.0+4.0*myran.doub());
x = laguer(aa,x,its);
Complex r = a[4].add(x.mul(a[5]));
r = a[3].add(x.mul(r));
r = a[2].add(x.mul(r));
r = a[1].add(x.mul(r));
r = a[0].add(x.mul(r));
dy[i] = r.abs();
//dy[i]=abs(a[0]+x*(a[1]+x*(a[2]+x*(a[3]+x*(a[4]+x*a[5])))));
}
System.out.printf("laguer: Maximum discrepancy = %f\n", maxel(dy));
localflag = maxel(dy) > sbeps;
globalflag = globalflag || localflag;
if (localflag) {
fail("*** laguer: Incorrect roots");
}
if (globalflag) System.out.println("Failed\n");
else System.out.println("Passed\n");
}
}