def run_correlator_test_real(self,
dtype,
nchan=256,
window=fx.null_window):
fakeData = 10.0 * numpy.random.rand(self.nAnt, nchan * 8) + 3.0
fakeData = fakeData.astype(dtype)
station = stations.parse_ssmif(_SSMIF)
antennas = station.antennas
freq, cps = fx.FXStokes(fakeData,
antennas[:self.nAnt],
LFFT=nchan,
window=window)
# Numpy comparison
for i in range(self.nAnt):
antennas[i].stand.x = 0.0
antennas[i].stand.y = 0.0
antennas[i].stand.z = 0.0
antennas[i].cable.length = 0.0
freq, cps = fx.FXStokes(fakeData,
antennas[:self.nAnt],
LFFT=nchan,
window=window)
cps2 = numpy.zeros_like(cps)
LFFT = cps.shape[2]
nFFT = fakeData.shape[1] // 2 // LFFT
wndw = window(2 * LFFT)
blc = 0
for i in range(0, self.nAnt // 2):
for j in range(i + 1, self.nAnt // 2):
for k in range(nFFT):
f1X = numpy.fft.fft(
fakeData[2 * i + 0, k * 2 * LFFT:(k + 1) * 2 * LFFT] *
wndw)[:LFFT]
f1Y = numpy.fft.fft(
fakeData[2 * i + 1, k * 2 * LFFT:(k + 1) * 2 * LFFT] *
wndw)[:LFFT]
f2X = numpy.fft.fft(
fakeData[2 * j + 0, k * 2 * LFFT:(k + 1) * 2 * LFFT] *
wndw)[:LFFT]
f2Y = numpy.fft.fft(
fakeData[2 * j + 1, k * 2 * LFFT:(k + 1) * 2 * LFFT] *
wndw)[:LFFT]
cps2[0, blc, :] += f1X * f2X.conj() + f1Y * f2Y.conj()
cps2[1, blc, :] += f1X * f2X.conj() - f1Y * f2Y.conj()
cps2[2, blc, :] += f1X * f2Y.conj() + f1X.conj() * f2Y
cps2[3,
blc, :] += (f1X * f2Y.conj() - f1X.conj() * f2Y) / 1j
blc += 1
cps2 /= (2 * LFFT * nFFT)
lsl.testing.assert_allclose(cps, cps2)
def test_correlator_complex_pfb(self):
"""Test the C-based PFB version of the correlator on complex-valued data."""
fakeData = numpy.random.rand(
self.nAnt, 1024 * 4) + 1j * numpy.random.rand(self.nAnt, 1024 * 4)
fakeData = fakeData.astype(numpy.csingle)
station = stations.parse_ssmif(_SSMIF)
antennas = station.antennas
freq, cps = fx.FXStokes(fakeData,
antennas[:self.nAnt],
pfb=True,
sample_rate=1e5,
central_freq=38e6)
# Numpy comparison
for i in range(self.nAnt):
antennas[i].stand.x = 0.0
antennas[i].stand.y = 0.0
antennas[i].stand.z = 0.0
antennas[i].cable.length = 0.0
freq, cps = fx.FXStokes(fakeData,
antennas[:self.nAnt],
pfb=True,
sample_rate=1e5,
central_freq=38e6)
cps2 = numpy.zeros_like(cps)
LFFT = cps.shape[2]
nFFT = fakeData.shape[1] // LFFT
blc = 0
for i in range(0, self.nAnt // 2):
for j in range(i + 1, self.nAnt // 2):
for k in range(nFFT):
f1X = numpy.fft.fftshift(
_pfb(fakeData[2 * i + 0, :], k * LFFT, LFFT))
f1Y = numpy.fft.fftshift(
_pfb(fakeData[2 * i + 1, :], k * LFFT, LFFT))
f2X = numpy.fft.fftshift(
_pfb(fakeData[2 * j + 0, :], k * LFFT, LFFT))
f2Y = numpy.fft.fftshift(
_pfb(fakeData[2 * j + 1, :], k * LFFT, LFFT))
cps2[0, blc, :] += f1X * f2X.conj() + f1Y * f2Y.conj()
cps2[1, blc, :] += f1X * f2X.conj() - f1Y * f2Y.conj()
cps2[2, blc, :] += f1X * f2Y.conj() + f1X.conj() * f2Y
cps2[3,
blc, :] += (f1X * f2Y.conj() - f1X.conj() * f2Y) / 1j
blc += 1
cps2 /= (LFFT * nFFT)
lsl.testing.assert_allclose(cps, cps2)
def test_correlator_real_pfb(self):
"""Test the C-based PFB version of the correlator on real-valued data."""
for dtype in (numpy.int8, numpy.int16, numpy.int32, numpy.int64,
numpy.float32, numpy.float64):
fakeData = 10.0 * numpy.random.rand(self.nAnt, 1024 * 4) + 3.0
fakeData = fakeData.astype(dtype)
station = stations.parse_ssmif(_SSMIF)
antennas = station.antennas
freq, cps = fx.FXStokes(fakeData, antennas[:self.nAnt], pfb=True)
# Numpy comparison
for i in range(self.nAnt):
antennas[i].stand.x = 0.0
antennas[i].stand.y = 0.0
antennas[i].stand.z = 0.0
antennas[i].cable.length = 0.0
freq, cps = fx.FXStokes(fakeData, antennas[:self.nAnt], pfb=True)
cps2 = numpy.zeros_like(cps)
LFFT = cps.shape[2]
nFFT = fakeData.shape[1] // 2 // LFFT
blc = 0
for i in range(0, self.nAnt // 2):
for j in range(i + 1, self.nAnt // 2):
for k in range(nFFT):
f1X = _pfb(fakeData[2 * i + 0, :], k * 2 * LFFT,
2 * LFFT)[:LFFT]
f1Y = _pfb(fakeData[2 * i + 1, :], k * 2 * LFFT,
2 * LFFT)[:LFFT]
f2X = _pfb(fakeData[2 * j + 0, :], k * 2 * LFFT,
2 * LFFT)[:LFFT]
f2Y = _pfb(fakeData[2 * j + 1, :], k * 2 * LFFT,
2 * LFFT)[:LFFT]
cps2[0, blc, :] += f1X * f2X.conj() + f1Y * f2Y.conj()
cps2[1, blc, :] += f1X * f2X.conj() - f1Y * f2Y.conj()
cps2[2, blc, :] += f1X * f2Y.conj() + f1X.conj() * f2Y
cps2[3, blc, :] += (f1X * f2Y.conj() -
f1X.conj() * f2Y) / 1j
blc += 1
cps2 /= (2 * LFFT * nFFT)
lsl.testing.assert_allclose(cps, cps2)
def test_correlator_baselines(self):
"""Test that the return_baselines keyword works."""
fakeData = numpy.random.rand(
self.nAnt, 1024) + 1j * numpy.random.rand(self.nAnt, 1024)
fakeData = fakeData.astype(numpy.csingle)
station = stations.parse_ssmif(_SSMIF)
antennas = station.antennas
blList, freq, cps = fx.FXStokes(fakeData,
antennas[:self.nAnt],
sample_rate=1e5,
central_freq=38e6,
return_baselines=True)
def test_correlator_gaincorrect(self):
"""Test appling gain correction to the correlator output."""
fakeData = numpy.random.rand(
self.nAnt, 1024) + 1j * numpy.random.rand(self.nAnt, 1024)
fakeData = fakeData.astype(numpy.csingle)
station = stations.parse_ssmif(_SSMIF)
antennas = station.antennas
freq, cps = fx.FXStokes(fakeData,
antennas[:self.nAnt],
sample_rate=1e5,
central_freq=38e6,
gain_correct=True)