test_DFT.c

#include <1chipml.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

static int compareFT(const unsigned length, dft_real* incomingReals,
                     dft_real* incomingImgs, dft_real* expectedReals,
                     dft_real* expectedImgs) {

  const dft_real epsilon = 1e-10;

  for (unsigned i = 0; i < length; ++i) {
    if (fabs(incomingReals[i] - expectedReals[i]) > epsilon ||
        fabs(incomingImgs[i] - expectedImgs[i]) > epsilon) {
      return 1;
    }
  }

  return 0;
}

static int knownTestingDFT(const unsigned length, fft_real* inputReals,
                           fft_real* inputImaginaries, fft_real* expectedReals,
                           fft_real* expectedImaginaries) {

  DFT(length, inputReals, inputImaginaries, 1);

  int isSimilar = compareFT(length, inputReals, inputImaginaries, expectedReals,
                            expectedImaginaries);

  printf("Known testing DFT: is the DFT working as intended? ");
  int returnCode = 0;
  if (isSimilar == 0) {
    printf("true\n");
    returnCode = 0;
  } else {
    printf("false\n");
    returnCode = 1;
  }
  return returnCode;
}

static int knownTestingDFTI(const unsigned length, fft_real* inputReals,
                            fft_real* inputImaginaries, fft_real* expectedReals,
                            fft_real* expectedImaginaries) {

  DFT(length, inputReals, inputImaginaries, -1);

  int isSimilar = compareFT(length, inputReals, inputImaginaries, expectedReals,
                            expectedImaginaries);

  printf("Known testing inverse DFT: is the DFT working as intended? ");
  int returnCode = 0;
  if (isSimilar == 0) {
    printf("true\n");
    returnCode = 0;
  } else {
    printf("false\n");
    returnCode = 1;
  }
  return returnCode;
}

int main() {

  int returnCode = 0;

  const unsigned length = 4;
  fft_real DFTinputReals[] = {8, 4, 8, 0};
  fft_real DFTinputImgs[] = {0, 0, 0, 0};
  fft_real DFTexpectedReals[] = {20, 0, 12, 0};
  fft_real DFTexpectedImgs[] = {0, -4, 0, 4};
  returnCode |= knownTestingDFT(length, DFTinputReals, DFTinputImgs,
                                DFTexpectedReals, DFTexpectedImgs);

  fft_real DFTIinputReals[] = {20, 0, 12, 0};
  fft_real DFTIinputImgs[] = {0, -4, 0, 4};
  fft_real DFTIexpectedReals[] = {8, 4, 8, 0};
  fft_real DFTIexpectedImgs[] = {0, 0, 0, 0};
  returnCode |= knownTestingDFTI(length, DFTIinputReals, DFTIinputImgs,
                                 DFTIexpectedReals, DFTIexpectedImgs);

  return returnCode;
}