.. _irf: *********************************** irf - Instrument response functions *********************************** .. currentmodule:: gammapy.irf Introduction ============ `gammapy.irf` handles instrument response functions (IRFs): * Effective area (AEFF) * Energy dispersion (EDISP) * Point spread function (PSF) Most of the formats defined at :ref:`gadf:iact-irf` are supported. Otherwise, at the moment, there is very little support for Fermi-LAT or other instruments. Most users will not use `gammapy.irf` directly, but will instead use IRFs as part of their spectrum, image or cube analysis to compute exposure and effective EDISP and PSF for a given dataset. Most (at some point maybe all) classes in `gammapy.irf` have an `gammapy.utils.nddata.NDDataArray` as data attribute to support interpolation. Getting Started =============== See :gp-notebook:`cta_1dc_introduction` for an example how to access IACT IRFs. Effective area ============== See `~gammapy.irf.EffectiveAreaTable` and `~gammapy.irf.EffectiveAreaTable2D`. Background ========== See `~gammapy.irf.Background2D` and `~gammapy.irf.Background2D`. PSF === The `~gammapy.irf.TablePSF` and `~gammapy.irf.EnergyDependentTablePSF` classes represent radially-symmetric PSFs where the PSF is given at a number of offsets. The `~gammapy.cube.PSFKernel` represents a PSF kernel. .. plot:: irf/plot_fermi_psf.py Energy Dispersion ================= The `~gammapy.irf.EnergyDispersion` class represents an energy migration matrix (finite probabilities per pixel) with ``y=log(energy_reco)``. The `~gammapy.irf.EnergyDispersion2D` class represents a probability density with ``y=energy_reco/energy_true`` that can also have a FOV offset dependence. .. plot:: irf/plot_edisp.py Using `gammapy.irf` =================== If you'd like to learn more about using `gammapy.irf`, read the following sub-pages: .. toctree:: :maxdepth: 1 theory aeff edisp Reference/API ============= .. automodapi:: gammapy.irf :no-inheritance-diagram: :include-all-objects: