DiffPy is a collection of Python libraries and applications for analyzing structure of materials from neutron or x-ray diffraction data.
diffpy is not a package by itself, it is rather a common top-level namespace for all of its components.
A library of python modules for carrying out tasks in diffraction. This is at an early stage of development and is not yet ready for code development by non-experts. Nevertheless, DiffPy has been already used to build two easy-to-use end applications.
* PDFgui - a program for full-profile fitting of the atomic pair distribution function (PDF) derived from x-ray or neutron diffraction data. This is a graphical front end for the PDFfit2 refinement program, with built in graphical and structure visualization capabilities. It is currently in beta release and it is distributed as a part of the DiffPy library.
* PDFfit2 - the structure refinement engine for fitting structural models to experimentally derived PDFs. This is used as calculation backend of PDFgui, but can be run separately.