def padproj(sptmap, padding=(4000, 4000), squaremap=True, proj0=True):
sptmap = np.pad(np.asarray(sptmap), padding, mode='constant')
if squaremap == True:
sptmap = sptmap[:,
int((sptmap.shape[1] / 2) -
(sptmap.shape[0] / 2)):int((sptmap.shape[1] / 2) +
(sptmap.shape[0] / 2))]
sptmap = maps.FlatSkyMap(
sptmap.copy(order='C'),
0.25 * core.G3Units.arcmin,
weighted=False,
proj=maps.MapProjection.Proj5,
alpha_center=0 * core.G3Units.deg,
delta_center=-57.5 * core.G3Units.deg,
coord_ref=maps.MapCoordReference.Equatorial,
units=core.G3TimestreamUnits.Tcmb,
pol_type=maps.MapPolType.T,
)
if proj0 == True:
MapProj0 = map_3g.Clone(False)
MapProj0.proj = maps.MapProjection.Proj0
maps.reproj_map(map_3g, MapProj0, interp=True)
sptmap = MapProj0
return sptmap
def __call__(self, frame):
if isinstance(frame,
core.G3Frame) and frame.type != core.G3FrameType.Map:
return
if "Q" in frame and self.stub.coord_ref != frame["Q"].coord_ref:
raise RuntimeError(
"Coordinate rotation of polarized maps is not implemented")
for key in ["T", "Q", "U", "Wpol", "Wunpol"]:
if key not in frame:
continue
m = frame.pop(key)
if key in "TQU":
mnew = self.stub.clone(False)
maps.reproj_map(m, mnew, rebin=self.rebin, interp=self.interp)
elif key in ["Wpol", "Wunpol"]:
mnew = maps.G3SkyMapWeights(self.stub, key == "Wpol")
for wkey in mnew.keys():
maps.reproj_map(m[wkey],
mnew[wkey],
rebin=self.rebin,
interp=self.interp)
frame[key] = mnew
return frame
def healpix_to_flatsky(
map_in, nest=False, map_stub=None, rebin=1, interp=False, **kwargs
):
"""
Re-pixelize a map from Healpix to one of the flat sky projections.
Parameters:
-----------
map_in: numpy array or HealpixSkyMap
The array containing the input healpix map to reproject.
nest[False]: bool
Ordering of the healpix map, if the input is a numpy array. Ring
ordering is assumed by default.
map_stub[None]: FlatSkyMap
Stub output map object to be used to construct the output map. If not
supplied, one will be constructed using the remaining keyword arguments.
rebin[1]: int
If supplied and >1, account for sub-pixel structure by integrating
over a sub-grid on each pixel of the given dimension. This avoids
aliasing of power at angular scales beyond the map resolution.
interp[false]: bool
If True, use bilinear interpolation to extract values from the input
map. Otherwise, the nearest-neighbor value is used.
All additional keyword arguments are passed to FlatSkyMap to construct
the output map object. Required if `map_stub` is not supplied,
otherwise ignored.
Returns:
--------
output_map: FlatSkyMap
The reprojected map
"""
# Construct the output map
if map_stub is None:
if isinstance(map_in, maps.HealpixSkyMap):
kwargs.setdefault("coord_ref", map_in.coord_ref)
kwargs.setdefault("pol_type", map_in.pol_type)
kwargs.setdefault("pol_conv", map_in.pol_conv)
map_out = maps.FlatSkyMap(**kwargs)
else:
if not isinstance(map_stub, maps.FlatSkyMap):
raise TypeError("Output stub must be a FlatSkyMap")
map_out = map_stub.Clone(False)
# Populate output map pixels with interpolation and rebinning
if not isinstance(map_in, maps.HealpixSkyMap):
map_in = maps.HealpixSkyMap(
map_in,
nested=nest,
coord_ref=map_out.coord_ref,
weighted=map_out.weighted,
units=map_out.units,
pol_type=map_out.pol_type,
pol_conv=map_out.pol_conv,
)
maps.reproj_map(map_in, map_out, rebin=rebin, interp=interp)
return map_out
def flatsky_to_healpix(
map_in, map_stub=None, rebin=1, interp=False, fullsky=False, **kwargs
):
"""
Re-pixelize a map to Healpix from one of the flat projections.
Parameters:
-----------
map_in: FlatSkyMap
The input map you want to reproject
map_stub[None]: HealpixSkyMap
Stub output map object to be used to construct the output map. If not
supplied, one will be constructed using the remaining keyword arguments.
rebin[1]: int
If supplied and >1, account for sub-pixel structure by integrating
over a sub-grid on each pixel of the given dimension. This avoids
aliasing of power at angular scales beyond the map resolution.
interp[false]: bool
If True, use bilinear interpolation to extract values from the input
map. Otherwise, the nearest-neighbor value is used.
fullsky[false]: bool
If True a full-sky numpy array representation of the map is returned.
Otherwise, a HealpixSkyMap instance is returned, containing only the
pixels that overlap with the input map.
All additional keyword arguments are passed to HealpixSkyMap to construct
the output map object. Required if `map_stub` is not supplied,
otherwise ignored.
Returns:
--------
output_map: numpy array or HealpixSkyMap
The array containing the healpix map
If `fullsky` is True, this is a numpy array, otherwise a
HealpixSkyMap instance.
"""
if not isinstance(map_in, maps.FlatSkyMap):
raise TypeError("Input must be a FlatSkyMap")
# Construct the output map
if map_stub is None:
kwargs.setdefault("coord_ref", map_in.coord_ref)
kwargs.setdefault("pol_type", map_in.pol_type)
kwargs.setdefault("pol_conv", map_in.pol_conv)
map_out = maps.HealpixSkyMap(**kwargs)
else:
if not isinstance(map_stub, maps.HealpixSkyMap):
raise TypeError("Output stub must be a HealpixSkyMap")
map_out = map_stub.Clone(False)
# optimize ringsparse storage
a0 = map_in.alpha_center
da = map_in.x_res * map_in.shape[1]
circ = 2 * np.pi * core.G3Units.rad
a0 = np.mod(a0 + circ, circ)
amin = np.mod(a0 - da + circ, circ)
amax = np.mod(a0 + da + circ, circ)
amin_shift = np.mod(a0 - da + circ + circ / 2, circ)
amax_shift = np.mod(a0 + da + circ + circ / 2, circ)
map_out.shift_ra = bool(np.abs(amax - amin) > np.abs(amax_shift - amin_shift))
# Populate output map pixels with interpolation and rebinning
maps.reproj_map(map_in, map_out, rebin=rebin, interp=interp)
if fullsky:
map_out.dense = True
return np.asarray(map_out)
return map_out
def flatsky_to_healpix(map_in,
map_stub=None,
rebin=1,
interp=False,
fullsky=False,
**kwargs):
"""
Re-pixelize a map to Healpix from one of the flat projections.
Parameters:
-----------
map_in: FlatSkyMap
The input map you want to reproject
map_stub[None]: HealpixSkyMap
Stub output map object to be used to construct the output map. If not
supplied, one will be constructed using the remaining keyword arguments.
rebin[1]: int
If supplied and >1, subdivide the output pixel by n x n with each
sub-pixel taking on the input map values at pixel center (with interp
or nearest neighbor). The output pixel takes on the average of the sub-pixel
values.
In the case that the input map has higher resolution than the output
map (and that the input map is not low-pass filtered to remove
information above the Nyquist freq. of the output map pixel), this
reduces aliasing compared with direct sampling. But there would still be
aliased power from the input map from freq above the ouput map pixel's
Nyquist.
interp[false]: bool
If True, use bilinear interpolation to extract values from the input
map. Otherwise, the nearest-neighbor value is used.
fullsky[false]: bool
If True a full-sky numpy array representation of the map is returned.
Otherwise, a HealpixSkyMap instance is returned, containing only the
pixels that overlap with the input map.
All additional keyword arguments are passed to HealpixSkyMap to construct
the output map object. Required if `map_stub` is not supplied,
otherwise ignored.
Maps can be rotated between Equatorial and Galactic coordinates, and/or
change polarization convention between COSMO and IAU, by setting the
appropriate attributes of the input and output maps. Attributes not defined
in the output map are assumed to be that of the input map.
Returns:
--------
output_map: numpy array or HealpixSkyMap
The array containing the healpix map. If `fullsky` is True, this is a
numpy array, otherwise a HealpixSkyMap instance.
"""
if not isinstance(map_in, maps.FlatSkyMap):
raise TypeError("Input must be a FlatSkyMap")
# Construct the output map
if map_stub is None:
kwargs.setdefault("coord_ref", map_in.coord_ref)
kwargs.setdefault("pol_type", map_in.pol_type)
kwargs.setdefault("pol_conv", map_in.pol_conv)
map_out = maps.HealpixSkyMap(**kwargs)
else:
if not isinstance(map_stub, maps.HealpixSkyMap):
raise TypeError("Output stub must be a HealpixSkyMap")
map_out = map_stub.clone(False)
# optimize ringsparse storage
a0 = map_in.alpha_center
da = map_in.x_res * map_in.shape[1]
circ = 2 * np.pi * core.G3Units.rad
a0 = np.mod(a0 + circ, circ)
amin = np.mod(a0 - da + circ, circ)
amax = np.mod(a0 + da + circ, circ)
amin_shift = np.mod(a0 - da + circ + circ / 2, circ)
amax_shift = np.mod(a0 + da + circ + circ / 2, circ)
map_out.shift_ra = bool(
np.abs(amax - amin) > np.abs(amax_shift - amin_shift))
# Populate output map pixels with interpolation and rebinning
maps.reproj_map(map_in, map_out, rebin=rebin, interp=interp)
if fullsky:
map_out.dense = True
return np.asarray(map_out)
return map_out
def healpix_to_flatsky(map_in,
nest=False,
map_stub=None,
rebin=1,
interp=False,
**kwargs):
"""
Re-pixelize a map from Healpix to one of the flat sky projections.
Parameters:
-----------
map_in: numpy array or HealpixSkyMap
The array containing the input healpix map to reproject.
nest[False]: bool
Ordering of the healpix map, if the input is a numpy array. Ring
ordering is assumed by default.
map_stub[None]: FlatSkyMap
Stub output map object to be used to construct the output map. If not
supplied, one will be constructed using the remaining keyword arguments.
rebin[1]: int
If supplied and >1, subdivide the output pixel by n x n with each
sub-pixel taking on the input map values at pixel center (with interp
or nearest neighbor). The output pixel takes on the average of the sub-pixel
values.
In the case that the input map has higher resolution than the output
map (and that the input map is not low-pass filtered to remove
information above the Nyquist freq. of the output map pixel), this
reduces aliasing compared with direct sampling. But there would still be
aliased power from the input map from freq above the ouput map pixel's
Nyquist.
interp[false]: bool
If True, use bilinear interpolation to extract values from the input
map. Otherwise, the nearest-neighbor value is used.
All additional keyword arguments are passed to FlatSkyMap to construct the
output map object. Required if `map_stub` is not supplied, otherwise
ignored.
Maps can be rotated between Equatorial and Galactic coordinates, and/or
change polarization convention between COSMO and IAU, by setting the
appropriate attributes of the input and output maps. Note that if the input
map is a numpy array representation of a healpix map, the coordinate system
and polarization convention are assumed to be that of the output map.
Conversely, attributes not defined in the output map are assumed to be
that of the input map.
Returns:
--------
output_map: FlatSkyMap
The reprojected map
"""
# Construct the output map
if map_stub is None:
if len(kwargs) == 0:
raise ValueError(
"Need to provide either a stub map or map parameters (projection, center, etc.)"
)
if isinstance(map_in, maps.HealpixSkyMap):
kwargs.setdefault("coord_ref", map_in.coord_ref)
kwargs.setdefault("pol_type", map_in.pol_type)
kwargs.setdefault("pol_conv", map_in.pol_conv)
map_out = maps.FlatSkyMap(**kwargs)
else:
if not isinstance(map_stub, maps.FlatSkyMap):
raise TypeError("Output stub must be a FlatSkyMap")
map_out = map_stub.clone(False)
# Populate output map pixels with interpolation and rebinning
if not isinstance(map_in, maps.HealpixSkyMap):
map_in = maps.HealpixSkyMap(
map_in,
nested=nest,
coord_ref=map_out.coord_ref,
weighted=map_out.weighted,
units=map_out.units,
pol_type=map_out.pol_type,
pol_conv=map_out.pol_conv,
)
maps.reproj_map(map_in, map_out, rebin=rebin, interp=interp)
return map_out
) fm = maps.maputils.healpix_to_flatsky(x, map_stub=fm_stub) x2 = maps.maputils.flatsky_to_healpix(fm, map_stub=x.clone(False)) hitpix = np.asarray(x2) > 0 assert(np.allclose(np.asarray(x)[hitpix], np.asarray(x2)[hitpix])) # Coordinate system rotations a = np.arange(49152) x = maps.HealpixSkyMap(a) alpha, delta = maps.get_ra_dec_map(x) # equatorial to galactic xgal = x.clone(False) x.coord_ref = maps.MapCoordReference.Equatorial xgal.coord_ref = maps.MapCoordReference.Galactic maps.reproj_map(x, xgal) ra, dec = maps.azel.convert_gal_to_radec(alpha, delta) pix = xgal.angles_to_pixels(ra, dec) assert(np.allclose(np.asarray(pix), np.asarray(xgal))) # ... and back xeq = x.clone(False) x.coord_ref = maps.MapCoordReference.Galactic xeq.coord_ref = maps.MapCoordReference.Equatorial maps.reproj_map(x, xeq) lon, lat = maps.azel.convert_radec_to_gal(alpha, delta) pix = xeq.angles_to_pixels(lon, lat) assert(np.allclose(np.asarray(pix), np.asarray(xeq)))