/** A test of {@link FloatFFT_2D#realForwardFull(FloatLargeArray)}. */
@Test
public void testRealForwardFullLarge() {
final FloatLargeArray actual = new FloatLargeArray(2 * numRows * numCols, false);
final float[][] expected0 = new float[numRows][2 * numCols];
final FloatLargeArray expected = new FloatLargeArray(numRows * 2 * numCols, false);
for (int r = 0; r < numRows; r++) {
for (int c = 0; c < numCols; c++) {
final float rnd = random.nextFloat();
actual.setDouble(r * numCols + c, rnd);
expected0[r][2 * c] = rnd;
}
}
fft.realForwardFull(actual);
complexForward(expected0);
for (int r = 0; r < numRows; r++) {
for (int c = 0; c < 2 * numCols; c++) {
expected.setDouble(2 * r * numCols + c, expected0[r][c]);
}
}
double rmse = IOUtils.computeRMSE(actual, expected);
Assert.assertEquals(
String.format(DEFAULT_MESSAGE, numThreads, numRows, numCols) + ", rmse = " + rmse,
0.0,
rmse,
EPS);
}
/** A test of {@link FloatFFT_2D#realForward(FloatLargeArray)}. */
@Test
public void testRealForwardLarge() {
if (!ConcurrencyUtils.isPowerOf2(numRows)) {
return;
}
if (!ConcurrencyUtils.isPowerOf2(numCols)) {
return;
}
final FloatLargeArray actual = new FloatLargeArray(2 * numRows * numCols, false);
final FloatLargeArray expected = new FloatLargeArray(numRows * 2 * numCols, false);
for (int r = 0; r < numRows; r++) {
for (int c = 0; c < numCols; c++) {
final float rnd = random.nextFloat();
actual.setDouble(r * numCols + c, rnd);
expected.setDouble(r * 2 * numCols + 2 * c, rnd);
}
}
fft.realForward(actual);
fft.complexForward(expected);
fillSymmetric(actual, numRows, numCols);
double rmse = IOUtils.computeRMSE(actual, expected);
Assert.assertEquals(
String.format(DEFAULT_MESSAGE, numThreads, numRows, numCols) + ", rmse = " + rmse,
0.0,
rmse,
EPS);
}
/**
* A test of {@link FloatFFT_2D#complexInverse(FloatLargeArray, boolean)}, with the second
* parameter set to <code>true</code>.
*/
@Test
public void testComplexInverseScaledLarge() {
final FloatLargeArray expected = new FloatLargeArray(2 * numRows * numCols, false);
final FloatLargeArray actual = new FloatLargeArray(2 * numRows * numCols, false);
for (int i = 0; i < actual.length(); i++) {
final float rnd = random.nextFloat();
actual.setDouble(i, rnd);
expected.setDouble(i, rnd);
}
fft.complexForward(actual);
fft.complexInverse(actual, true);
double rmse = IOUtils.computeRMSE(actual, expected);
Assert.assertEquals(
String.format(DEFAULT_MESSAGE, numThreads, numRows, numCols) + ", rmse = " + rmse,
0.0,
rmse,
EPS);
}
/**
* A test of {@link FloatFFT_2D#realInverseFull(FloatLargeArray, boolean)}, with the second
* parameter set to <code>false</code>.
*/
@Test
public void testRealInverseFullUnscaledLarge() {
final FloatLargeArray actual = new FloatLargeArray(2 * numRows * numCols, false);
final FloatLargeArray expected = new FloatLargeArray(2 * numRows * numCols, false);
for (int r = 0; r < numRows; r++) {
for (int c = 0; c < numCols; c++) {
final float rnd = random.nextFloat();
final int index = r * numCols + c;
actual.set(index, rnd);
expected.setDouble(2 * index, rnd);
}
}
// TODO If the two following lines are permuted, this causes an array
// index out of bounds exception.
fft.complexInverse(expected, false);
fft.realInverseFull(actual, false);
double rmse = IOUtils.computeRMSE(actual, expected);
Assert.assertEquals(
String.format(DEFAULT_MESSAGE, numThreads, numRows, numCols) + ", rmse = " + rmse,
0.0,
rmse,
EPS);
}
private static void fillSymmetric(final FloatLargeArray a, int rowsl, int columnsl) {
final long twon2 = 2 * columnsl;
long idx1, idx2, idx3, idx4;
long n1d2 = rowsl / 2;
for (long r = (rowsl - 1); r >= 1; r--) {
idx1 = r * columnsl;
idx2 = 2 * idx1;
for (long c = 0; c < columnsl; c += 2) {
a.setDouble(idx2 + c, a.getDouble(idx1 + c));
a.setDouble(idx1 + c, 0);
a.setDouble(idx2 + c + 1, a.getDouble(idx1 + c + 1));
a.setDouble(idx1 + c + 1, 0);
}
}
for (long r = 1; r < n1d2; r++) {
idx2 = r * twon2;
idx3 = (rowsl - r) * twon2;
a.setDouble(idx2 + columnsl, a.getDouble(idx3 + 1));
a.setDouble(idx2 + columnsl + 1, -a.getDouble(idx3));
}
for (long r = 1; r < n1d2; r++) {
idx2 = r * twon2;
idx3 = (rowsl - r + 1) * twon2;
for (long c = columnsl + 2; c < twon2; c += 2) {
a.setDouble(idx2 + c, a.getDouble(idx3 - c));
a.setDouble(idx2 + c + 1, -a.getDouble(idx3 - c + 1));
}
}
for (long r = 0; r <= rowsl / 2; r++) {
idx1 = r * twon2;
idx4 = ((rowsl - r) % rowsl) * twon2;
for (long c = 0; c < twon2; c += 2) {
idx2 = idx1 + c;
idx3 = idx4 + (twon2 - c) % twon2;
a.setDouble(idx3, a.getDouble(idx2));
a.setDouble(idx3 + 1, -a.getDouble(idx2 + 1));
}
}
a.setDouble(columnsl, -a.getDouble(1));
a.setDouble(1, 0);
idx1 = n1d2 * twon2;
a.setDouble(idx1 + columnsl, -a.getDouble(idx1 + 1));
a.setDouble(idx1 + 1, 0);
a.setDouble(idx1 + columnsl + 1, 0);
}
