def test_samples_per_frame(self):
expected = self.fh.read()
sa = SetAttribute(self.fh, samples_per_frame=11111)
assert sa.shape == (33333, 8)
data = sa.read()
assert np.all(data == expected[:33333])
sa2 = SetAttribute(self.fh,
samples_per_frame=11111,
shape=self.fh.shape)
assert sa2.shape == self.fh.shape
data2 = sa2.read()
assert np.all(data2 == expected)
def test_dtype(self):
expected = self.fh.read()
sa = SetAttribute(self.fh, dtype='f2')
assert isinstance(sa.dtype, np.dtype)
assert sa.dtype == 'f2'
data = sa.read()
assert data.dtype == 'f2'
assert np.all(data == expected.astype('f2'))
def test_set_start_time(self):
expected = self.fh.read()
offset = 0.1 * u.s
sa = SetAttribute(self.fh, start_time=self.fh.start_time + offset)
assert sa.start_time == self.fh.start_time + offset
for attr in ('sample_rate', 'samples_per_frame', 'shape', 'dtype'):
assert getattr(sa, attr) == getattr(self.fh, attr)
data = sa.read()
assert np.all(data == expected)
sa.seek(10)
data2 = sa.read(10)
assert np.all(data2 == expected[10:20])
sa.seek(10 / sa.sample_rate)
data3 = sa.read(10)
assert np.all(data3 == expected[10:20])
sa.seek(sa.start_time + 10 / self.fh.sample_rate)
data4 = sa.read(10)
assert np.all(data4 == expected[10:20])
for attr in ('frequency', 'sideband', 'polarization'):
with pytest.raises(AttributeError):
getattr(sa, attr)
sa.close()
def test_complex_stream(self, tmpdir):
filename = str(tmpdir.join('copy.hdf5'))
with baseband.vdif.open(baseband.data.SAMPLE_AROCHIME_VDIF,
'rs',
sample_rate=800 * u.MHz / 2048) as fh:
wrapped = SetAttribute(fh)
data = wrapped.read()
wrapped.seek(0)
with hdf5.open(filename, 'w', template=wrapped) as f5w:
assert f5w.complex_data
assert f5w.header0.encoded_dtype == 'c8'
wrapped.read(out=f5w)
with hdf5.open(filename, 'r') as f5r:
self.check(wrapped, f5r,
('sample_shape', 'dtype', 'sample_rate', 'time'))
assert f5r.header0.encoded_dtype == 'c8'
recovered = f5r.read()
# Cannot recover exactly, given scaling, but should be within
# tolerance for float16.
assert_array_equal(recovered, data)
def test_complex_stream_as_c4(self, tmpdir):
filename = str(tmpdir.join('copy.hdf5'))
with baseband.vdif.open(baseband.data.SAMPLE_AROCHIME_VDIF,
'rs',
sample_rate=800 * u.MHz / 2048) as fh:
wrapped = SetAttribute(fh)
data = wrapped.read()
wrapped.seek(0)
with hdf5.open(filename, 'w', template=wrapped,
encoded_dtype='c4') as f5w:
assert f5w.complex_data
assert f5w.header0.encoded_dtype == hdf5.payload.DTYPE_C4
wrapped.read(out=f5w)
with hdf5.open(filename, 'r') as f5r:
self.check(wrapped, f5r,
('sample_shape', 'dtype', 'sample_rate', 'time'))
assert f5r.header0.encoded_dtype == hdf5.payload.DTYPE_C4
recovered = f5r.read()
# Cannot recover exactly, given scaling, but should be within
# tolerance for float16.
assert np.allclose(recovered, data, atol=0, rtol=np.finfo('f2').eps)
def test_set_basics(self):
expected = self.fh.read()
frequency = 311.25 * u.MHz + (np.arange(8.) // 2) * 16. * u.MHz
sideband = np.tile([-1, +1], 4)
sa = SetAttribute(self.fh, frequency=frequency, sideband=sideband)
assert np.all(sa.frequency == frequency)
assert np.all(sa.sideband == sideband)
for attr in ('start_time', 'sample_rate', 'samples_per_frame', 'shape',
'dtype'):
assert getattr(sa, attr) == getattr(self.fh, attr)
# Check that frequency does not propagate.
frequency[...] = 0
assert np.all(sa.frequency != 0)
sideband[...] = 0
assert np.all(np.abs(sa.sideband) == 1)
# Check data can be read.
data = sa.read()
assert np.all(data == expected)
# Check we didn't magically define polarization.
with pytest.raises(AttributeError):
sa.polarization
sa.close()