package com.nr.test.test_chapter13;
import static com.nr.NRUtil.SQR;
import static java.lang.Math.abs;
import static java.lang.Math.acos;
import static java.lang.Math.cos;
import static org.junit.Assert.fail;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import com.nr.sp.BartlettWin;
import com.nr.sp.Spectreg;
public class Test_bartlett {
@Before
public void setUp() throws Exception {
}
@After
public void tearDown() throws Exception {
}
@Test
public void test() {
double maxf=0,maxs,pi=acos(-1.0),sbeps;;
int i,j,maxi=0,M=128,N=2*M,K=64;
double[] data=new double[N],spec=new double[M+1],freq=new double[M+1];
boolean localflag, globalflag=false;
// Test bartlett
System.out.println("Testing bartlett");
BartlettWin bartlett = new BartlettWin();
Spectreg sp =new Spectreg(M);
for (i=0;i<K;i++) {
// Generate a data set
for (j=0;j<N;j++)
data[j]=cos(2.0*pi*64*j/N);
sp.adddataseg(data,bartlett);
}
spec=sp.spectrum();
freq=sp.frequencies();
// for (i=0;i<M+1;i++)
// System.out.printf(freq[i] << " " << spec[i]);
maxs=-1.0;
for (i=0;i<M+1;i++) {
if (spec[i] > maxs) {
maxf=freq[i];
maxs=spec[i];
maxi=i;
}
}
sbeps=1.e-15;
localflag=abs(maxf-0.25) > sbeps;
globalflag = globalflag || localflag;
if (localflag) {
fail("*** bartlett: Spectrum maximum is at wrong frequency");
}
localflag = false;
for (i=1;i<5;i++) {
localflag = localflag || (spec[maxi+2*i]/maxs > sbeps);
localflag = localflag || (spec[maxi-2*i]/maxs > sbeps);
}
globalflag = globalflag || localflag;
if (localflag) {
fail("*** bartlett: Even numbered channels from the maximum should be zero for Bartlett window");
}
// test for symmetry
sbeps=1.e-12;
localflag=false;
for (i=0;i<5;i++) {
// System.out.printf(abs(spec[maxi+2*i+1]/spec[maxi-2*i-1]-1.0));
localflag = localflag || abs(spec[maxi+2*i+1]/spec[maxi-2*i-1]-1.0) > sbeps;
globalflag = globalflag || localflag;
if (localflag) {
fail("*** bartlett: Sidelobes at odd numbered channels from maximum are not symmetrical");
}
}
// Test for amplitude
sbeps=1.e-2;
localflag=false;
for (i=1;i<5;i++) {
// System.out.printf(spec[maxi+2*i+1]/maxs << " " << spec[maxi-2*i-1]/maxs);
// System.out.printf(abs(spec[maxi+2*i+1]/spec[maxi+1]*SQR(SQR(2*i+1))-1.0));
localflag = localflag || abs(spec[maxi+2*i+1]/spec[maxi+1]*SQR(SQR(2*i+1))-1.0) > sbeps;
globalflag = globalflag || localflag;
if (localflag) {
fail("*** bartlett: Odd numbered channels from the maximum are not in correct proportion");
}
}
if (globalflag) System.out.println("Failed\n");
else System.out.println("Passed\n");
}
}