ctaoirf - IRF Management

IRFHouse

Manages and loads multiple CTA Instrument Response Functions (IRFs).

Constructor

IRFHouse(base_directory: str | Path, check_irfs: bool = False)

Parameters:

Parameter	Type	Description
base_directory	str | Path	Root directory containing IRF files
check_irfs	bool	If True, verify all IRF files exist during initialization

Example:

from sensipy.ctaoirf import IRFHouse

house = IRFHouse(base_directory="./IRFs/CTAO")

Methods

get_irf()

Load a specific IRF configuration.

get_irf(
    site: Site | str,
    configuration: Configuration | str,
    zenith: Zenith | int,
    duration: Duration | int,
    azimuth: Azimuth | str,
    version: Version | str,
) -> IRF

Parameters:

Parameter	Type	Options
site	str	"north", "south"
configuration	str	"alpha", "omega", "alpha_lst"
zenith	int	20, 40, 60 (degrees)
duration	int	1800, 18000, 180000 (seconds)
azimuth	str	"north", "south", "average"
version	str	"prod5-v0.1", "prod3b-v2"

Returns: IRF object

Example:

irf = house.get_irf(
    site="south",
    configuration="alpha",
    zenith=20,
    duration=1800,
    azimuth="average",
    version="prod5-v0.1",
)

check_all_paths()

Verify all expected IRF files exist.

check_all_paths() -> None

Prints status for all IRF combinations and reports missing files.

house.check_all_paths()

IRF

Represents a single Instrument Response Function configuration.

Attributes

Attribute	Type	Description
filepath	Path	Path to IRF FITS file
site	Site	Observatory site (north/south)
configuration	Configuration	Telescope configuration
zenith	Zenith | int	Zenith angle
duration	Duration | int	IRF duration
azimuth	Azimuth	Azimuth direction
version	Version	IRF production version
base_directory	Path	Base IRF directory

Properties

energy_limits

Get energy range of the IRF.

energy_min, energy_max = irf.energy_limits
print(f"Energy range: {energy_min} to {energy_max}")

Methods

__repr__()

String representation of the IRF.

print(irf)
# Output:
# CTA IRF [prod5-v0.1]
#     filepath: .../CTA-Performance-prod5-v0.1-South-20deg...
#     config: alpha
#     site: south
#     zenith: 20º
#     duration: 1800s
#     azimuth: average

__fspath__()

Return file path (allows IRF to be used as path-like object).

from gammapy.irf import load_irf_dict_from_file

irf_dict = load_irf_dict_from_file(irf)  # Uses __fspath__()

Enumerations

Site

class Site(str, Enum):
    south = "south"
    north = "north"

Configuration

class Configuration(str, Enum):
    alpha = "alpha"
    omega = "omega"
    alpha_lst = "alpha_lst"

Zenith

class Zenith(IntEnum):
    z20 = 20
    z40 = 40
    z60 = 60

Duration

class Duration(IntEnum):
    t1800 = 1800
    t18000 = 18000
    t180000 = 180000

Azimuth

class Azimuth(str, Enum):
    south = "south"
    north = "north"
    average = "average"

Version

class Version(str, Enum):
    prod5_v0p1 = "prod5-v0.1"
    prod3b_v2 = "prod3b-v2"

Using Enums

from sensipy.ctaoirf import IRFHouse, Site, Zenith, Configuration

house = IRFHouse(base_directory="./IRFs/CTAO")

irf = house.get_irf(
    site=Site.south,
    configuration=Configuration.alpha,
    zenith=Zenith.z20,
    duration=1800,
    azimuth="average",
    version="prod5-v0.1",
)