# Licensed under a 3-clause BSD style license - see LICENSE.rst
import logging
from astropy.io import fits
from gammapy.data.hdu_index_table import HDUIndexTable
from gammapy.utils.fits import HDULocation
from gammapy.utils.scripts import make_path
__all__ = ["load_irf_dict_from_file"]
log = logging.getLogger(__name__)
IRF_DL3_AXES_SPECIFICATION = {
"THETA": {"name": "offset", "interp": "lin"},
"ENERG": {"name": "energy_true", "interp": "log"},
"ETRUE": {"name": "energy_true", "interp": "log"},
"RAD": {"name": "rad", "interp": "lin"},
"DETX": {"name": "fov_lon", "interp": "lin"},
"DETY": {"name": "fov_lat", "interp": "lin"},
"MIGRA": {"name": "migra", "interp": "lin"},
}
COMMON_HEADERS = {
"HDUCLASS": "GADF",
"HDUDOC": "https://github.com/open-gamma-ray-astro/gamma-astro-data-formats",
"HDUVERS": "0.2",
}
COMMON_IRF_HEADERS = {
**COMMON_HEADERS,
"HDUCLAS1": "RESPONSE",
}
# The key is the class tag.
# TODO: extend the info here with the minimal header info
IRF_DL3_HDU_SPECIFICATION = {
"bkg_3d": {
"extname": "BACKGROUND",
"column_name": "BKG",
"mandatory_keywords": {
**COMMON_IRF_HEADERS,
"HDUCLAS2": "BKG",
"HDUCLAS3": "FULL-ENCLOSURE", # added here to have HDUCLASN in order
"HDUCLAS4": "BKG_3D",
"FOVALIGN": "RADEC",
},
},
"bkg_2d": {
"extname": "BACKGROUND",
"column_name": "BKG",
"mandatory_keywords": {
**COMMON_IRF_HEADERS,
"HDUCLAS2": "BKG",
"HDUCLAS3": "FULL-ENCLOSURE", # added here to have HDUCLASN in order
"HDUCLAS4": "BKG_2D",
},
},
"edisp_2d": {
"extname": "ENERGY DISPERSION",
"column_name": "MATRIX",
"mandatory_keywords": {
**COMMON_IRF_HEADERS,
"HDUCLAS2": "EDISP",
"HDUCLAS3": "FULL-ENCLOSURE", # added here to have HDUCLASN in order
"HDUCLAS4": "EDISP_2D",
},
},
"psf_table": {
"extname": "PSF_2D_TABLE",
"column_name": "RPSF",
"mandatory_keywords": {
**COMMON_IRF_HEADERS,
"HDUCLAS2": "RPSF",
"HDUCLAS3": "FULL-ENCLOSURE", # added here to have HDUCLASN in order
"HDUCLAS4": "PSF_TABLE",
},
},
"psf_3gauss": {
"extname": "PSF_2D_GAUSS",
"column_name": {
"sigma_1": "SIGMA_1",
"sigma_2": "SIGMA_2",
"sigma_3": "SIGMA_3",
"scale": "SCALE",
"ampl_2": "AMPL_2",
"ampl_3": "AMPL_3",
},
"mandatory_keywords": {
**COMMON_IRF_HEADERS,
"HDUCLAS2": "RPSF",
"HDUCLAS3": "FULL-ENCLOSURE", # added here to have HDUCLASN in order
"HDUCLAS4": "PSF_3GAUSS",
},
},
"psf_king": {
"extname": "PSF_2D_KING",
"column_name": {
"sigma": "SIGMA",
"gamma": "GAMMA",
},
"mandatory_keywords": {
**COMMON_IRF_HEADERS,
"HDUCLAS2": "RPSF",
"HDUCLAS3": "FULL-ENCLOSURE", # added here to have HDUCLASN in order
"HDUCLAS4": "PSF_KING",
},
},
"aeff_2d": {
"extname": "EFFECTIVE AREA",
"column_name": "EFFAREA",
"mandatory_keywords": {
**COMMON_IRF_HEADERS,
"HDUCLAS2": "EFF_AREA",
"HDUCLAS3": "FULL-ENCLOSURE", # added here to have HDUCLASN in order
"HDUCLAS4": "AEFF_2D",
},
},
"rad_max_2d": {
"extname": "RAD_MAX",
"column_name": "RAD_MAX",
"mandatory_keywords": {
**COMMON_IRF_HEADERS,
"HDUCLAS2": "RAD_MAX",
"HDUCLAS3": "POINT-LIKE",
"HDUCLAS4": "RAD_MAX_2D",
},
},
}
IRF_MAP_HDU_SPECIFICATION = {
"edisp_kernel_map": "edisp",
"edisp_map": "edisp",
"psf_map": "psf",
"psf_map_reco": "psf",
}
def gadf_is_pointlike(header):
"""Check if a GADF IRF is pointlike based on the header."""
return header.get("HDUCLAS3") == "POINT-LIKE"
class UnknownHDUClass(IOError):
"""Raised when a file contains an unknown HDUCLASS."""
def _get_hdu_type_and_class(header):
"""Get gammapy hdu_type and class from FITS header.
Contains a workaround to support CTA 1DC irf file.
"""
hdu_clas2 = header.get("HDUCLAS2", "")
hdu_clas4 = header.get("HDUCLAS4", "")
clas2_to_type = {"rpsf": "psf", "eff_area": "aeff"}
hdu_type = clas2_to_type.get(hdu_clas2.lower(), hdu_clas2.lower())
hdu_class = hdu_clas4.lower()
if hdu_type not in HDUIndexTable.VALID_HDU_TYPE:
raise UnknownHDUClass(f"HDUCLAS2={hdu_clas2}, HDUCLAS4={hdu_clas4}")
# workaround for CTA 1DC files with non-compliant HDUCLAS4 names
if hdu_class not in HDUIndexTable.VALID_HDU_CLASS:
hdu_class = f"{hdu_type}_{hdu_class}"
if hdu_class not in HDUIndexTable.VALID_HDU_CLASS:
raise UnknownHDUClass(f"HDUCLAS2={hdu_clas2}, HDUCLAS4={hdu_clas4}")
return hdu_type, hdu_class
[docs]def load_irf_dict_from_file(filename):
"""Load all available IRF components from given file into a dictionary.
If multiple IRFs of the same type are present, the first encountered is returned.
Parameters
----------
filename : str or `~pathlib.Path`
Path to the file containing the IRF components, if EVENTS and GTI HDUs
are included in the file, they are ignored.
Returns
-------
irf_dict : dict of `~gammapy.irf.IRF`
Dictionary with instances of the Gammapy objects corresponding
to the IRF components.
"""
from .rad_max import RadMax2D
filename = make_path(filename)
irf_dict = {}
is_pointlike = False
with fits.open(filename) as hdulist:
for hdu in hdulist:
hdu_clas1 = hdu.header.get("HDUCLAS1", "").lower()
# not an IRF component
if hdu_clas1 != "response":
continue
is_pointlike |= hdu.header.get("HDUCLAS3") == "POINT-LIKE"
try:
hdu_type, hdu_class = _get_hdu_type_and_class(hdu.header)
except UnknownHDUClass as e:
log.warning("File has unknown class %s", e)
continue
loc = HDULocation(
hdu_class=hdu_class,
hdu_name=hdu.name,
file_dir=filename.parent,
file_name=filename.name,
)
if hdu_type in irf_dict.keys():
log.warning(f"more than one HDU of {hdu_type} type found")
log.warning(
f"loaded the {irf_dict[hdu_type].meta['EXTNAME']} HDU in the dictionary"
)
continue
data = loc.load()
irf_dict[hdu_type] = data
if is_pointlike and "rad_max" not in irf_dict:
irf_dict["rad_max"] = RadMax2D.from_irf(irf_dict["aeff"])
return irf_dict