This document highlights important changes and additions to Sherpa functionality in the CIAO 4.12.1 Sherpa release.
Sherpa version for CIAO 4.12.1 was released on July 14, 2020. Sherpa in CIAO runs under Python 3.5 (when installed with ciao-install) or Python 3.7, 3.6, or 3.5 (when installed using the conda package manager). The full list of the Sherpa updates is given in the Release Notes. The major updates in this release include:
- load_multi_arfs and load_multi_rmfs caching fixed which would otherwise prevent fit from running when using multi-order responses in modeling grating spectra.
- calc_photon_flux and calc_energy_flux enhanced to better handle monochromatic flux densities and fluxes where the energy bounds fall in between the model grid bin edges. A new model argument is also added to calculate "unabsorbed" fluxes by specifying specific model components.
- model caching is now optional.
- Bug Fixes
Help can be found either via Python's native help function (that is, Python docstrings), or with the ahelp command (which can be used from both the command line and within the Sherpa interactive environment.
The Python docstrings are the preferred way to access help on the Sherpa functions and models, since the ahelp files may not have been updated either to add new functions or models, or to reflect recent improvements.
A recent development for "standalone Sherpa" is the creation of the Sherpa documentation website. This provides on-line access to the Python docstrings, as well as general documentation on how to use Sherpa. It is aimed at users who want to use the more object-orientated interface provided by Sherpa rather than the functions from the sherpa.astro.ui module documented on this site, as well as not being tailored to CIAO users, but it is useful for the more advanced Sherpa users who want to use Sherpa in complex Python pipelines.