Data Formats¶

Note

Since November 2015 there is the main-page project. This page contains extra information about which formats we support in Gammapy and which class corresponds to which format.

Where available and useful existing standards are used, e.g. for spectral data the X-ray community has developed the PHA, ARF and RMF file formats and they have developed powerful tools to work with data in that format.

Overview¶

Here’s an overview of the file formats supported by Gammapy and Gammalib:

Type	Format Name	Gammapy	Gammalib
Events	EVENTS	`EventList`	GEventList
Effective area	AEFF_2D	`EffectiveAreaTable2D`	GCTAAeff2D
Effective area	ARF	`EffectiveAreaTable`	GCTAAeffArf
Energy dispersion	EDISP_2D	`EnergyDispersion2D`	GCTAEdisp2D
Energy dispersion	RMF	`EDispKernel`	GCTAEdispRMF
PSF	PSF_2D_GAUSS	`EnergyDependentMultiGaussPSF`	GCTAPsf2D
PSF	PSF_2D_KING	`PSFKing`	GCTAPsfKing
PSF	no spec available	`TablePSF`	GCTAPsfVector
PSF	gtpsf output	`EnergyDependentTablePSF`	N/A
PSF	psf_table	`PSF3D`	GCTAPsfTable
PSF	no spec available	N/A	GCTACubePsf
Background	BACKGROUND_3D	`Background3D`	GCTABackground3D
Background	BACKGROUND_2D	`Background2D`	N/A
Background	no spec available	N/A	GCTAModelRadialAcceptance
Background	no spec available	N/A	GCTACubeBackground
Exposure	EXPOSURE_3D	`Map`	GCTACubeExposure
Counts	3D	`Map`	GCTAEventCube
Counts	Image	`Map`	GSkyMap
Counts	PHA	`RegionNDMap`	GPha

Notes¶

The Gammalib docs contain a nice overview of IRFs here and detailed explanations of some IRF here.
We probably should unify / shorten the IRF class names in Gammapy.
There’s quite a few classes in Gammapy that don’t have a well-defined format. We should add a way to serialise every class and document the format for easier interop.
Maybe add info which format is used by Fermi, HESS HD/PA, CTA?
For every format there should be one or several test data files. This could even be in a repo that’s shared by Gammalib / Gammapy.