def __init__(self,
x_start: u.Quantity,
y_start: u.Quantity,
x_step: u.Quantity,
y_step: u.Quantity,
frequency: u.Quantity,
samples: np.ndarray,
*,
band: str,
antenna: Optional[str] = None,
receiver: Optional[str] = None) -> None:
super().__init__()
# Canonicalise the units to simplify to_hdf5 (and also remove the
# cost of conversions when methods are called with canonical units,
# with a side benefit of failing hard if the wrong units are
# provided).
self.x_start = x_start.to(u.m)
self.y_start = y_start.to(u.m)
self.x_step = x_step.to(u.m)
self.y_step = y_step.to(u.m)
self.frequency = frequency.astype(np.float32,
copy=False,
casting='same_kind')
if len(frequency) > 1:
self._frequency_resolution = np.min(np.diff(frequency))
if self._frequency_resolution <= 0 * u.Hz:
raise ValueError('frequencies must be strictly increasing')
else:
# We can set _frequency_resolution easily enough, but
# scipy.interpolate also refuses to work with just a single (or zero)
# elements on the interpolation axis.
raise NotImplementedError(
'at least 2 frequencies are currently required')
self.samples = samples.astype(np.complex64,
copy=False,
casting='same_kind')
scale = samples.shape[-1] * samples.shape[-2] # Normalisation factor
self._interp_samples = scipy.interpolate.interp1d(
self.frequency.to_value(u.Hz),
self.samples / scale,
axis=0,
copy=False,
bounds_error=False,
fill_value=np.nan,
assume_sorted=True)
self._antenna = antenna
self._receiver = receiver
self._band = band
def __init__(self,
frequency: u.Quantity,
coefs: Tuple[ArrayLike, ArrayLike],
correlator_efficiency: Optional[float],
*,
band: str,
antenna: Optional[str] = None,
receiver: Optional[str] = None) -> None:
super().__init__()
self.frequency = frequency.astype(np.float32, copy=False, casting='same_kind')
if len(frequency) > 1:
self._frequency_resolution = np.min(np.diff(frequency))
if self._frequency_resolution <= 0 * u.Hz:
raise ValueError('frequencies must be strictly increasing')
else:
raise NotImplementedError('at least 2 frequencies are currently required')
self.coefs = coefs
if correlator_efficiency is not None:
self._correlator_efficiency = correlator_efficiency
else:
self._correlator_efficiency = 1.0
self._band = band
self._antenna = antenna
self._receiver = receiver
