def from_hdulist(cls, hdu_list):
"""Create `EnergyDependentTablePSF` from ``gtpsf`` format HDU list.
Parameters
----------
hdu_list : `~astropy.io.fits.HDUList`
HDU list with ``THETA`` and ``PSF`` extensions.
"""
rad_axis = MapAxis.from_table_hdu(hdu_list["THETA"], format="gtpsf")
table = Table.read(hdu_list["PSF"])
energy_axis_true = MapAxis.from_table(table, format="gtpsf")
exposure = table["Exposure"].data * u.Unit("cm2 s")
data = table["Psf"].data
return cls(axes=[energy_axis_true, rad_axis],
exposure=exposure,
data=data,
unit="sr-1")
def from_hdulist(
cls,
hdulist,
hdu=None,
hdu_bands=None,
exposure_hdu=None,
exposure_hdu_bands=None,
format="gadf",
):
"""Create from `~astropy.io.fits.HDUList`.
Parameters
----------
hdulist : `~astropy.fits.HDUList`
HDU list.
hdu : str
Name or index of the HDU with the IRF map.
hdu_bands : str
Name or index of the HDU with the IRF map BANDS table.
exposure_hdu : str
Name or index of the HDU with the exposure map data.
exposure_hdu_bands : str
Name or index of the HDU with the exposure map BANDS table.
format : {"gadf", "gtpsf"}
File format
Returns
-------
irf_map : `IRFMap`
IRF map.
"""
if format == "gadf":
if hdu is None:
hdu = IRF_MAP_HDU_SPECIFICATION[cls.tag]
irf_map = Map.from_hdulist(hdulist,
hdu=hdu,
hdu_bands=hdu_bands,
format=format)
if exposure_hdu is None:
exposure_hdu = IRF_MAP_HDU_SPECIFICATION[cls.tag] + "_exposure"
if exposure_hdu in hdulist:
exposure_map = Map.from_hdulist(hdulist,
hdu=exposure_hdu,
hdu_bands=exposure_hdu_bands,
format=format)
else:
exposure_map = None
elif format == "gtpsf":
rad_axis = MapAxis.from_table_hdu(hdulist["THETA"], format=format)
table = Table.read(hdulist["PSF"])
energy_axis_true = MapAxis.from_table(table, format=format)
geom_psf = RegionGeom.create(region=None,
axes=[rad_axis, energy_axis_true])
psf_map = Map.from_geom(geom=geom_psf,
data=table["Psf"].data,
unit="sr-1")
geom_exposure = geom_psf.squash("rad")
exposure_map = Map.from_geom(geom=geom_exposure,
data=table["Exposure"].data,
unit="cm2 s")
return cls(psf_map=psf_map, exposure_map=exposure_map)
else:
raise ValueError(f"Format {format} not supported")
return cls(irf_map, exposure_map)
