Welcome to PyXspec’s documentation!

Now compatible with Python 3

PyXspec is an object oriented Python interface to the XSPEC spectral-fitting program. It provides an alternative to Tcl, the sole scripting language for standard Xspec usage. With PyXspec loaded, a user can run Xspec with Python language scripts or interactively at a Python shell prompt.


The source code distribution of XSPEC is required for using PyXspec

Download the PDF version of this manual

Build and Install


PyXspec was developed by Craig Gordon and Keith Arnaud
HEASARC Software Development, Astrophysics Science Division,
Code 660.1, NASA/GSFC, Greenbelt MD 20771

Please send questions, comments, and bug reports to xspec12@athena.gsfc.nasa.gov