def visibility_scatter_w(vis: Visibility, **kwargs) -> List[Visibility]:
if isinstance(vis, BlockVisibility):
avis = coalesce_visibility(vis, **(kwargs))
visibility_list = visibility_scatter(avis, vis_iter=vis_wstack_iter, **kwargs)
else:
visibility_list = visibility_scatter(vis, vis_iter=vis_wstack_iter, **kwargs)
return visibility_list
def test_coalesce_decoalesce_time(self):
cvis = coalesce_visibility(self.blockvis, time_coal=1.0, frequency_coal=0.0, max_frequency_coal=1)
assert numpy.min(cvis.frequency) == numpy.min(self.frequency)
assert numpy.min(cvis.frequency) > 0.0
dvis = decoalesce_visibility(cvis)
assert dvis.nvis == self.blockvis.nvis
dvis = decoalesce_visibility(cvis, overwrite=True)
assert dvis.nvis == self.blockvis.nvis
def scatter_vis(vis):
# Scatter along the visibility iteration axis
if isinstance(vis, BlockVisibility):
avis = coalesce_visibility(vis, **kwargs)
else:
avis = vis
result = [
create_visibility_from_rows(avis, rows)
for rows in vis_iter(avis, vis_slices=vis_slices, **kwargs)
]
return result
def scatter_vis(vis):
if isinstance(vis, BlockVisibility):
avis = coalesce_visibility(vis, **kwargs)
else:
avis = vis
result = [
create_visibility_from_rows(avis, rows)
for rows in vis_iter(avis, vis_slices=vis_slices, **kwargs)
]
assert len(result) == vis_slices, "result %s, vis_slices %d" % (
str(result), vis_slices)
return result
def test_coalesce_decoalesce_singletime(self):
self.times = numpy.array([0.0])
self.blockvis = create_blockvisibility(self.lowcore, self.times, self.frequency, phasecentre=self.phasecentre,
weight=1.0, polarisation_frame=PolarisationFrame('stokesI'),
channel_bandwidth=self.channel_bandwidth)
# Fill in the vis values so each can be uniquely identified
self.blockvis.data['vis'] = range(self.blockvis.nvis)
cvis = coalesce_visibility(self.blockvis, time_coal=1.0)
assert numpy.min(cvis.frequency) == numpy.min(self.frequency)
assert numpy.min(cvis.frequency) > 0.0
dvis = decoalesce_visibility(cvis)
assert dvis.nvis == self.blockvis.nvis
def visibility_gather_w(visibility_list, vis, **kwargs):
if type(vis) == BlockVisibility:
cvis = coalesce_visibility(vis, **kwargs)
return decoalesce_visibility(
visibility_gather(visibility_list,
cvis,
vis_iter=vis_wstack_iter,
**kwargs))
else:
return visibility_gather(visibility_list,
vis,
vis_iter=vis_wstack_iter,
**kwargs)
def invert_timeslice_single(vis: Visibility,
im: Image,
dopsf,
normalize=True,
**kwargs) -> (Image, numpy.ndarray):
"""Process single time slice
Extracted for re-use in parallel version
:param vis: Visibility to be inverted
:param im: image template (not changed)
:param dopsf: Make the psf instead of the dirty image
:param normalize: Normalize by the sum of weights (True)
"""
inchan, inpol, ny, nx = im.shape
if not isinstance(vis, Visibility):
avis = coalesce_visibility(vis, **kwargs)
else:
avis = vis
log.debug("invert_timeslice: inverting using time slices")
avis, p, q = fit_uvwplane(avis, remove=True)
workimage, sumwt = invert_2d_base(avis,
im,
dopsf,
normalize=normalize,
**kwargs)
finalimage = create_empty_image_like(im)
# Use griddata to do the conversion. This could be improved. Only cubic is possible in griddata.
# The interpolation is ok for invert since the image is smooth.
# Calculate nominal and distorted coordinates. The image is in distorted coordinates so we
# need to convert back to nominal
lnominal, mnominal, ldistorted, mdistorted = lm_distortion(
workimage, -p, -q)
for chan in range(inchan):
for pol in range(inpol):
finalimage.data[chan, pol, ...] = \
griddata((mdistorted.flatten(), ldistorted.flatten()),
values=workimage.data[chan, pol, ...].flatten(),
method='cubic',
xi=(mnominal.flatten(), lnominal.flatten()),
fill_value=0.0,
rescale=True).reshape(finalimage.data[chan, pol, ...].shape)
return finalimage, sumwt
def predict_timeslice_single(vis: Visibility,
model: Image,
predict=predict_2d_base,
remove=True,
**kwargs) -> Visibility:
""" Predict using a single time slices.
This fits a single plane and corrects the image geometry.
:param vis: Visibility to be predicted
:param model: model image
:param predict:
:param remove: Remove fitted w (so that wprojection will do the right thing)
:return: resulting visibility (in place works)
"""
log.debug("predict_timeslice: predicting using time slices")
inchan, inpol, ny, nx = model.shape
vis.data['vis'] *= 0.0
if not isinstance(vis, Visibility):
avis = coalesce_visibility(vis, **kwargs)
else:
avis = vis
# Fit and remove best fitting plane for this slice
avis, p, q = fit_uvwplane(avis, remove=remove)
# Calculate nominal and distorted coordinate systems. We will convert the model
# from nominal to distorted before predicting.
workimage = copy_image(model)
# Use griddata to do the conversion. This could be improved. Only cubic is possible in griddata.
# The interpolation is ok for invert since the image is smooth but for clean images the
# interpolation is particularly poor, leading to speckle in the residual image.
lnominal, mnominal, ldistorted, mdistorted = lm_distortion(model, -p, -q)
for chan in range(inchan):
for pol in range(inpol):
workimage.data[chan, pol, ...] = \
griddata((mnominal.flatten(), lnominal.flatten()),
values=workimage.data[chan, pol, ...].flatten(),
xi=(mdistorted.flatten(), ldistorted.flatten()),
method='cubic',
fill_value=0.0,
rescale=True).reshape(workimage.data[chan, pol, ...].shape)
avis = predict(avis, workimage, **kwargs)
return avis
def test_predict_sky_components_coalesce(self):
sc = create_low_test_skycomponents_from_gleam(flux_limit=10.0,
polarisation_frame=PolarisationFrame("stokesI"),
frequency=self.frequency, kind='cubic',
phasecentre=SkyCoord("17h20m31s", "-00d58m45s"),
radius=0.1)
self.config = create_named_configuration('LOWBD2-CORE')
self.phasecentre = SkyCoord("17h20m31s", "-00d58m45s")
sampling_time = 3.76
self.times = numpy.arange(0.0, + 300 * sampling_time, sampling_time)
self.vis = create_blockvisibility(self.config, self.times, self.frequency, phasecentre=self.phasecentre,
weight=1.0, polarisation_frame=PolarisationFrame('stokesI'),
channel_bandwidth=self.channel_bandwidth)
self.vis = predict_skycomponent_blockvisibility(self.vis, sc)
cvt = coalesce_visibility(self.vis, time_coal=1.0)
assert cvt.cindex is not None
def gather_vis(results, vis):
# Gather across the visibility iteration axis
assert vis is not None
if isinstance(vis, BlockVisibility):
avis = coalesce_visibility(vis, **kwargs)
else:
avis = vis
for i, rows in enumerate(
vis_iter(avis, vis_slices=vis_slices, **kwargs)):
assert i < len(results), "Insufficient results for the gather"
if rows is not None and results[i] is not None:
avis.data['vis'][rows] = results[i].data['vis']
if isinstance(vis, BlockVisibility):
return decoalesce_visibility(avis, **kwargs)
else:
return avis
def predict_2d_base(vis: Union[BlockVisibility, Visibility], model: Image,
**kwargs) -> Union[BlockVisibility, Visibility]:
""" Predict using convolutional degridding.
This is at the bottom of the layering i.e. all transforms are eventually expressed in terms of
this function. Any shifting needed is performed here.
:param vis: Visibility to be predicted
:param model: model image
:return: resulting visibility (in place works)
"""
if isinstance(vis, BlockVisibility):
log.debug("imaging.predict: coalescing prior to prediction")
avis = coalesce_visibility(vis, **kwargs)
else:
avis = vis
assert isinstance(avis, Visibility), avis
_, _, ny, nx = model.data.shape
padding = {}
if get_parameter(kwargs, "padding", False):
padding = {'padding': get_parameter(kwargs, "padding", False)}
spectral_mode, vfrequencymap = get_frequency_map(avis, model)
polarisation_mode, vpolarisationmap = get_polarisation_map(avis, model)
uvw_mode, shape, padding, vuvwmap = get_uvw_map(avis, model, **padding)
kernel_name, gcf, vkernellist = get_kernel_list(avis, model, **kwargs)
uvgrid = fft((pad_mid(model.data, int(round(padding * nx))) *
gcf).astype(dtype=complex))
avis.data['vis'] = convolutional_degrid(vkernellist,
avis.data['vis'].shape, uvgrid,
vuvwmap, vfrequencymap,
vpolarisationmap)
# Now we can shift the visibility from the image frame to the original visibility frame
svis = shift_vis_to_image(avis, model, tangent=True, inverse=True)
if isinstance(vis, BlockVisibility) and isinstance(svis, Visibility):
log.debug("imaging.predict decoalescing post prediction")
return decoalesce_visibility(svis)
else:
return svis
def predict_wstack_single(vis, model, remove=True, **kwargs) -> Visibility:
""" Predict using a single w slices.
This processes a single w plane, rotating out the w beam for the average w
:param vis: Visibility to be predicted
:param model: model image
:return: resulting visibility (in place works)
"""
if not isinstance(vis, Visibility):
log.debug("predict_wstack_single: Coalescing")
avis = coalesce_visibility(vis, **kwargs)
else:
avis = vis
log.debug("predict_wstack_single: predicting using single w slice")
avis.data['vis'] *= 0.0
# We might want to do wprojection so we remove the average w
w_average = numpy.average(avis.w)
avis.data['uvw'][..., 2] -= w_average
tempvis = copy_visibility(avis)
# Calculate w beam and apply to the model. The imaginary part is not needed
workimage = copy_image(model)
w_beam = create_w_term_like(model, w_average, vis.phasecentre)
# Do the real part
workimage.data = w_beam.data.real * model.data
avis = predict_2d_base(avis, workimage, **kwargs)
# and now the imaginary part
workimage.data = w_beam.data.imag * model.data
tempvis = predict_2d_base(tempvis, workimage, **kwargs)
avis.data['vis'] -= 1j * tempvis.data['vis']
if not remove:
avis.data['uvw'][..., 2] += w_average
if isinstance(vis, BlockVisibility) and isinstance(avis, Visibility):
log.debug("imaging.predict decoalescing post prediction")
return decoalesce_visibility(avis)
else:
return avis
def predict_with_vis_iterator(vis: Visibility, model: Image, vis_iter=vis_slice_iter,
predict=predict_2d, **kwargs) -> Visibility:
"""Iterate through prediction in chunks
This knows about the structure of predict in different execution frameworks but not
anything about the actual processing.
"""
log.debug("predict_with_vis_iterator: Processing chunks")
if not isinstance(vis, Visibility):
svis = coalesce_visibility(vis, **kwargs)
else:
svis = vis
# Do each chunk in turn
for rows in vis_iter(svis, **kwargs):
if numpy.sum(rows) and svis is not None:
visslice = create_visibility_from_rows(svis, rows)
visslice.data['vis'][...] = 0.0
visslice = predict(visslice, model, **kwargs)
svis.data['vis'][rows] += visslice.data['vis']
return svis
def invert_with_vis_iterator(vis: Visibility, im: Image, dopsf=False, normalize=True, vis_iter=vis_slice_iter,
invert=invert_2d, **kwargs):
""" Invert using a specified iterator and invert
This knows about the structure of invert in different execution frameworks but not
anything about the actual processing.
:param vis:
:param im:
:param dopsf: Make the psf instead of the dirty image
:param normalize: Normalize by the sum of weights (True)
:param kwargs:
:return:
"""
resultimage = create_empty_image_like(im)
if type(vis) is not Visibility:
svis = coalesce_visibility(vis, **kwargs)
else:
svis = vis
i = 0
for rows in vis_iter(svis, **kwargs):
if numpy.sum(rows) and svis is not None:
visslice = create_visibility_from_rows(svis, rows)
workimage, sumwt = invert(visslice, im, dopsf, normalize=False, **kwargs)
resultimage.data += workimage.data
if i == 0:
totalwt = sumwt
else:
totalwt += sumwt
i += 1
if normalize:
resultimage = normalize_sumwt(resultimage, totalwt)
return resultimage, totalwt
def predict_2d_base(vis: Visibility, model: Image, **kwargs) -> Visibility:
""" Predict using convolutional degridding.
This is at the bottom of the layering i.e. all transforms are eventually expressed in terms of
this function. Any shifting needed is performed here.
:param vis: Visibility to be predicted
:param model: model image
:return: resulting visibility (in place works)
"""
if type(vis) is not Visibility:
avis = coalesce_visibility(vis, **kwargs)
else:
avis = vis
_, _, ny, nx = model.data.shape
# print(model.shape)
spectral_mode, vfrequencymap = get_frequency_map(avis, model) # 可以并行
polarisation_mode, vpolarisationmap = get_polarisation_map(
avis, model, **kwargs) # 可以并行
uvw_mode, shape, padding, vuvwmap = get_uvw_map(avis, model,
**kwargs) # 可以并行
kernel_name, gcf, vkernellist = get_kernel_list(avis, model, **kwargs)
uvgrid = fft((pad_mid(model.data, int(round(padding * nx))) *
gcf).astype(dtype=complex))
avis.data['vis'] = convolutional_degrid(vkernellist,
avis.data['vis'].shape, uvgrid,
vuvwmap, vfrequencymap,
vpolarisationmap)
# Now we can shift the visibility from the image frame to the original visibility frame
svis = shift_vis_to_image(avis, model, tangent=True, inverse=True)
if type(vis) is not Visibility:
return decoalesce_visibility(svis)
else:
return svis
def invert_2d_base_timing(vis: Visibility, im: Image, dopsf: bool = False, normalize: bool = True, **kwargs) \
-> (Image, numpy.ndarray, tuple):
""" Invert using 2D convolution function, including w projection optionally
Use the image im as a template. Do PSF in a separate call.
This is at the bottom of the layering i.e. all transforms are eventually expressed in terms
of this function. . Any shifting needed is performed here.
:param vis: Visibility to be inverted
:param im: image template (not changed)
:param dopsf: Make the psf instead of the dirty image
:param normalize: Normalize by the sum of weights (True)
:return: resulting image
"""
opt = get_parameter(kwargs, 'opt', False)
if not opt:
log.debug('Using original algorithm')
else:
log.debug('Using optimized algorithm')
if not isinstance(vis, Visibility):
svis = coalesce_visibility(vis, **kwargs)
else:
svis = copy_visibility(vis)
if dopsf:
svis.data['vis'] = numpy.ones_like(svis.data['vis'])
svis = shift_vis_to_image(svis, im, tangent=True, inverse=False)
nchan, npol, ny, nx = im.data.shape
padding = {}
if get_parameter(kwargs, "padding", False):
padding = {'padding': get_parameter(kwargs, "padding", False)}
spectral_mode, vfrequencymap = get_frequency_map(svis, im, opt)
polarisation_mode, vpolarisationmap = get_polarisation_map(svis, im)
uvw_mode, shape, padding, vuvwmap = get_uvw_map(svis, im, **padding)
kernel_name, gcf, vkernellist = get_kernel_list(svis, im, **kwargs)
# Optionally pad to control aliasing
imgridpad = numpy.zeros(
[nchan, npol,
int(round(padding * ny)),
int(round(padding * nx))],
dtype='complex')
# Use original algorithm
if not opt:
time_grid = -time.time()
imgridpad, sumwt = convolutional_grid(vkernellist, imgridpad,
svis.data['vis'],
svis.data['imaging_weight'],
vuvwmap, vfrequencymap,
vpolarisationmap)
time_grid += time.time()
# Use optimized algorithm
else:
time_grid = -time.time()
kernel_indices, kernels = vkernellist
ks0, ks1, ks2, ks3 = kernels[0].shape
kernels_c = numpy.zeros((len(kernels), ks0, ks1, ks2, ks3),
dtype=kernels[0].dtype)
for i in range(len(kernels)):
kernels_c[i, ...] = kernels[i]
vfrequencymap_c = numpy.array(vfrequencymap, dtype=numpy.int32)
sumwt = numpy.zeros((imgridpad.shape[0], imgridpad.shape[1]),
dtype=numpy.float64)
convolutional_grid_c(imgridpad, sumwt, native_order(svis.data['vis']),
native_order(svis.data['imaging_weight']),
native_order(kernels_c),
native_order(kernel_indices),
native_order(vuvwmap),
native_order(vfrequencymap_c))
time_grid += time.time()
# Fourier transform the padded grid to image, multiply by the gridding correction
# function, and extract the unpadded inner part.
# Normalise weights for consistency with transform
sumwt /= float(padding * int(round(padding * nx)) * ny)
imaginary = get_parameter(kwargs, "imaginary", False)
if imaginary:
log.debug("invert_2d_base: retaining imaginary part of dirty image")
result = extract_mid(ifft(imgridpad) * gcf, npixel=nx)
resultreal = create_image_from_array(result.real, im.wcs)
resultimag = create_image_from_array(result.imag, im.wcs)
if normalize:
resultreal = normalize_sumwt(resultreal, sumwt)
resultimag = normalize_sumwt(resultimag, sumwt)
return resultreal, sumwt, resultimag
else:
# Use original algorithm
if not opt:
time_ifft = -time.time()
inarr = ifft(imgridpad)
time_ifft += time.time()
# Use optimized algorithm
else:
time_ifft = -time.time()
inarr = numpy.zeros(imgridpad.shape, dtype=imgridpad.dtype)
ifft_c(inarr, imgridpad)
time_ifft += time.time()
result = extract_mid(numpy.real(inarr) * gcf, npixel=nx)
resultimage = create_image_from_array(result, im.wcs)
if normalize:
resultimage = normalize_sumwt(resultimage, sumwt)
return resultimage, sumwt, (time_grid, time_ifft)
def predict_2d_base_timing(vis: Visibility, model: Image,
**kwargs) -> (Visibility, tuple):
""" Predict using convolutional degridding.
This is at the bottom of the layering i.e. all transforms are eventually expressed in terms of
this function. Any shifting needed is performed here.
:param vis: Visibility to be predicted
:param model: model image
:return: resulting visibility (in place works)
"""
if not isinstance(vis, Visibility):
avis = coalesce_visibility(vis, **kwargs)
else:
avis = vis
_, _, ny, nx = model.data.shape
opt = get_parameter(kwargs, 'opt', False)
if not opt:
log.debug('Using original algorithm')
else:
log.debug('Using optimized algorithm')
padding = {}
if get_parameter(kwargs, "padding", False):
padding = {'padding': get_parameter(kwargs, "padding", False)}
spectral_mode, vfrequencymap = get_frequency_map(avis, model, opt)
polarisation_mode, vpolarisationmap = get_polarisation_map(avis, model)
uvw_mode, shape, padding, vuvwmap = get_uvw_map(avis, model, **padding)
kernel_name, gcf, vkernellist = get_kernel_list(avis, model, **kwargs)
inarr = (pad_mid(model.data, int(round(padding * nx))) *
gcf).astype(dtype=complex)
# Use original algorithm
if not opt:
time_fft = -time.time()
uvgrid = fft(inarr)
time_fft += time.time()
time_degrid = -time.time()
vt = convolutional_degrid(vkernellist, avis.data['vis'].shape, uvgrid,
vuvwmap, vfrequencymap, vpolarisationmap)
time_degrid += time.time()
# Use optimized algorithm
else:
time_fft = -time.time()
uvgrid = numpy.zeros(inarr.shape, dtype=inarr.dtype)
fft_c(uvgrid, inarr)
time_fft += time.time()
time_degrid = -time.time()
kernel_indices, kernels = vkernellist
ks0, ks1, ks2, ks3 = kernels[0].shape
kernels_c = numpy.zeros((len(kernels), ks0, ks1, ks2, ks3),
dtype=kernels[0].dtype)
for i in range(len(kernels)):
kernels_c[i, ...] = kernels[i]
vfrequencymap_c = numpy.array(vfrequencymap, dtype=numpy.int32)
vt = numpy.zeros(avis.data['vis'].shape, dtype=numpy.complex128)
convolutional_degrid_c(vt, native_order(kernels_c),
native_order(kernel_indices),
native_order(uvgrid), native_order(vuvwmap),
native_order(vfrequencymap_c))
time_degrid += time.time()
avis.data['vis'] = vt
# Now we can shift the visibility from the image frame to the original visibility frame
svis = shift_vis_to_image(avis, model, tangent=True, inverse=True)
if not isinstance(vis, Visibility):
svis = decoalesce_visibility(svis)
return svis, (time_degrid, time_fft)
def invert_2d_base(vis: Visibility, im: Image, dopsf: bool = False, normalize: bool = True, **kwargs) \
-> (Image, numpy.ndarray):
""" Invert using 2D convolution function, including w projection optionally
Use the image im as a template. Do PSF in a separate call.
This is at the bottom of the layering i.e. all transforms are eventually expressed in terms
of this function. . Any shifting needed is performed here.
:param vis: Visibility to be inverted
:param im: image template (not changed)
:param dopsf: Make the psf instead of the dirty image
:param normalize: Normalize by the sum of weights (True)
:return: resulting image
"""
if type(vis) is not Visibility:
svis = coalesce_visibility(vis, **kwargs)
else:
svis = copy_visibility(vis)
if dopsf:
svis.data['vis'] = numpy.ones_like(svis.data['vis'])
svis = shift_vis_to_image(svis, im, tangent=True, inverse=False)
nchan, npol, ny, nx = im.data.shape
spectral_mode, vfrequencymap = get_frequency_map(svis, im)
polarisation_mode, vpolarisationmap = get_polarisation_map(
svis, im, **kwargs)
uvw_mode, shape, padding, vuvwmap = get_uvw_map(svis, im, **kwargs)
kernel_name, gcf, vkernellist = get_kernel_list(svis, im, **kwargs)
# Optionally pad to control aliasing
imgridpad = numpy.zeros(
[nchan, npol,
int(round(padding * ny)),
int(round(padding * nx))],
dtype='complex')
imgridpad, sumwt = convolutional_grid(vkernellist, imgridpad,
svis.data['vis'],
svis.data['imaging_weight'], vuvwmap,
vfrequencymap, vpolarisationmap)
# Fourier transform the padded grid to image, multiply by the gridding correction
# function, and extract the unpadded inner part.
# Normalise weights for consistency with transform
sumwt /= float(padding * int(round(padding * nx)) * ny)
imaginary = get_parameter(kwargs, "imaginary", False)
if imaginary:
log.debug("invert_2d_base: retaining imaginary part of dirty image")
result = extract_mid(ifft(imgridpad) * gcf, npixel=nx)
resultreal = create_image_from_array(result.real, im.wcs)
resultimag = create_image_from_array(result.imag, im.wcs)
if normalize:
resultreal = normalize_sumwt(resultreal, sumwt)
resultimag = normalize_sumwt(resultimag, sumwt)
return resultreal, sumwt, resultimag
else:
result = extract_mid(numpy.real(ifft(imgridpad)) * gcf, npixel=nx)
resultimage = create_image_from_array(result, im.wcs)
if normalize:
resultimage = normalize_sumwt(resultimage, sumwt)
return resultimage, sumwt
def visibility_gather_w(visibility_list: List[Visibility], vis: Visibility, **kwargs) -> Visibility:
if isinstance(vis, BlockVisibility):
cvis = coalesce_visibility(vis, **kwargs)
return decoalesce_visibility(visibility_gather(visibility_list, cvis, vis_iter=vis_wstack_iter, **kwargs))
else:
return visibility_gather(visibility_list, vis, vis_iter=vis_wstack_iter, **kwargs)
def scatter_vis(vis):
if isinstance(vis, BlockVisibility):
avis = coalesce_visibility(vis, **kwargs)
else:
avis = vis
return [create_visibility_from_rows(vis, rows) for rows in vis_iter(avis, vis_slices=vis_slices, **kwargs)]
def test_coalesce_decoalesce_tbgrid_vis_null(self):
cvis = coalesce_visibility(self.blockvis, time_coal=0.0)
assert numpy.min(cvis.frequency) == numpy.min(self.frequency)
assert numpy.min(cvis.frequency) > 0.0
def visibility_scatter_w(vis, **kwargs):
if type(vis) == BlockVisibility:
avis = coalesce_visibility(vis, **(kwargs))
return visibility_scatter(avis, vis_iter=vis_wstack_iter, **kwargs)
else:
return visibility_scatter(vis, vis_iter=vis_wstack_iter, **kwargs)
image_graph = create_test_image(
frequency=frequency,
phasecentre=phasecentre,
cellsize=0.001,
polarisation_frame=PolarisationFrame('linear')) # data [2,4,256,256]
blockvis = create_blockvisibility(
lowcore,
times=times,
frequency=frequency,
channel_bandwidth=channel_bandwidth,
phasecentre=phasecentre,
weight=1,
polarisation_frame=PolarisationFrame('linear'),
integration_time=1.0)
# 创建用blockvis的vis, 压缩率为0
vis = coalesce_visibility(blockvis)
# vis = create_visibility(lowcore, times=times, frequency=frequency,
# channel_bandwidth=channel_bandwidth,
# phasecentre=phasecentre, weight=1,
# polarisation_frame=PolarisationFrame('stokesIQUV'),
# integration_time=1.0) # vis [baselines, times, nchan, npol]
class TestImageIterators(unittest.TestCase):
#===predict_module===
# def test_visibility_class(self):
# for mode in ['pol', 'npol', 'chan']:
# viss, vis_share = visibility_to_visibility_para(vis, mode)
# new_vis = visibility_para_to_visibility(viss, mode, vis_share)
# visibility_right(vis, new_vis)
# print("%s visibility test passed" % mode)
def invert_function(vis,
im: Image,
dopsf=False,
normalize=True,
context='2d',
inner=None,
**kwargs):
""" Invert using algorithm specified by context:
* 2d: Two-dimensional transform
* wstack: wstacking with either vis_slices or wstack (spacing between w planes) set
* wprojection: w projection with wstep (spacing between w places) set, also kernel='wprojection'
* timeslice: snapshot imaging with either vis_slices or timeslice set. timeslice='auto' does every time
* facets: Faceted imaging with facets facets on each axis
* facets_wprojection: facets AND wprojection
* facets_wstack: facets AND wstacking
* wprojection_wstack: wprojection and wstacking
:param vis:
:param im:
:param dopsf: Make the psf instead of the dirty image (False)
:param normalize: Normalize by the sum of weights (True)
:param context: Imaging context e.g. '2d', 'timeslice', etc.
:param inner: Inner loop 'vis'|'image'
:param kwargs:
:return: Image, sum of weights
"""
c = imaging_context(context)
vis_iter = c['vis_iterator']
image_iter = c['image_iterator']
invert = c['invert']
if inner is None:
inner = c['inner']
if not isinstance(vis, Visibility):
svis = coalesce_visibility(vis, **kwargs)
else:
svis = vis
resultimage = create_empty_image_like(im)
if inner == 'image':
totalwt = None
for rows in vis_iter(svis, **kwargs):
if numpy.sum(rows):
visslice = create_visibility_from_rows(svis, rows)
sumwt = 0.0
workimage = create_empty_image_like(im)
for dpatch in image_iter(workimage, **kwargs):
result, sumwt = invert(visslice,
dpatch,
dopsf,
normalize=False,
**kwargs)
# Ensure that we fill in the elements of dpatch instead of creating a new numpy arrray
dpatch.data[...] = result.data[...]
# Assume that sumwt is the same for all patches
if totalwt is None:
totalwt = sumwt
else:
totalwt += sumwt
resultimage.data += workimage.data
else:
# We assume that the weight is the same for all image iterations
totalwt = None
workimage = create_empty_image_like(im)
for dpatch in image_iter(workimage, **kwargs):
totalwt = None
for rows in vis_iter(svis, **kwargs):
if numpy.sum(rows):
visslice = create_visibility_from_rows(svis, rows)
result, sumwt = invert(visslice,
dpatch,
dopsf,
normalize=False,
**kwargs)
# Ensure that we fill in the elements of dpatch instead of creating a new numpy arrray
dpatch.data[...] += result.data[...]
if totalwt is None:
totalwt = sumwt
else:
totalwt += sumwt
resultimage.data += workimage.data
workimage.data[...] = 0.0
assert totalwt is not None, "No valid data found for imaging"
if normalize:
resultimage = normalize_sumwt(resultimage, totalwt)
return resultimage, totalwt
def predict_function(vis,
model: Image,
context='2d',
inner=None,
**kwargs) -> Visibility:
"""Predict visibilities using algorithm specified by context
* 2d: Two-dimensional transform
* wstack: wstacking with either vis_slices or wstack (spacing between w planes) set
* wprojection: w projection with wstep (spacing between w places) set, also kernel='wprojection'
* timeslice: snapshot imaging with either vis_slices or timeslice set. timeslice='auto' does every time
* facets: Faceted imaging with facets facets on each axis
* facets_wprojection: facets AND wprojection
* facets_wstack: facets AND wstacking
* wprojection_wstack: wprojection and wstacking
:param vis:
:param model: Model image, used to determine image characteristics
:param context: Imaing context e.g. '2d', 'timeslice', etc.
:param inner: Inner loop 'vis'|'image'
:param kwargs:
:return:
"""
c = imaging_context(context)
vis_iter = c['vis_iterator']
image_iter = c['image_iterator']
predict = c['predict']
if inner is None:
inner = c['inner']
if not isinstance(vis, Visibility):
svis = coalesce_visibility(vis, **kwargs)
else:
svis = vis
result = copy_visibility(vis, zero=True)
if inner == 'image':
for rows in vis_iter(svis, **kwargs):
if numpy.sum(rows):
visslice = create_visibility_from_rows(svis, rows)
visslice.data['vis'][...] = 0.0
# Iterate over images
for dpatch in image_iter(model, **kwargs):
result.data['vis'][...] = 0.0
result = predict(visslice, dpatch, **kwargs)
svis.data['vis'][rows] += result.data['vis']
else:
# Iterate over images
for dpatch in image_iter(model, **kwargs):
for rows in vis_iter(svis, **kwargs):
if numpy.sum(rows):
visslice = create_visibility_from_rows(svis, rows)
result.data['vis'][...] = 0.0
result = predict(visslice, dpatch, **kwargs)
svis.data['vis'][rows] += result.data['vis']
return svis
