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package org.nd4j.linalg.fft.test;

import org.junit.Test;
import org.nd4j.linalg.api.complex.IComplexNDArray;
import org.nd4j.linalg.factory.Nd4j;
import org.nd4j.linalg.fft.VectorFFT;
import org.nd4j.linalg.fft.VectorIFFT;

import static org.junit.Assert.assertEquals;

/**
 * Created by agibsonccc on 9/6/14.
 */
public abstract class BaseIFFTTests {
    @Test
    public void testIfft() {
        double[] ffted = {10.2,5.,-3.0,-1.};
        double[] orig = {3.5999999999999996,2, 6.5999999999999996 ,3};
        IComplexNDArray c = Nd4j.createComplex(orig, new int[]{2});
        IComplexNDArray assertion = Nd4j.createComplex(ffted,new int[]{2});

        assertEquals(assertion,new VectorFFT(2).apply(c));
        IComplexNDArray iffted = new VectorIFFT(2).apply(assertion.dup());
        assertEquals(iffted,c);



        double[] ffted2 = {17.8,9.,-1,-8.6,4.6,3.};
        double[] orig2 = {3.6,2, 6.6 ,3,7.6 ,4};
        double[] fftOrig2 = { 17.8000000,9,-4.3660254,-0.6339746,-2.6339746,-2.3660254};
        IComplexNDArray c2 =  Nd4j.createComplex(orig2,new int[]{3});

        IComplexNDArray fftOrig2Arr =  Nd4j.createComplex(fftOrig2,new int[]{fftOrig2.length / 2});
        IComplexNDArray fftOrig2Test = new VectorFFT(fftOrig2Arr.length()).apply(c2);
        assertEquals(fftOrig2Arr,fftOrig2Test);

        IComplexNDArray ifftTestFor =  Nd4j.createComplex(new double[]{3.6,2,6.6,3,7.6,4},new int[]{3});
        IComplexNDArray ifftTest = new VectorIFFT(fftOrig2Arr.length()).apply(fftOrig2Arr);
        assertEquals(ifftTestFor,ifftTest);
    }




}