latest version:   qgraf-3.3

qgraf is a computer program that can generate Feynman diagrams and represent them by symbolic expressions; no graphical representation is generated, though. It was written to assist in large perturbative calculations, in the context of Quantum Field Theory.

  • Programming language: FORTRAN 77 (there should be some evolution in the next major release).
    Binaries/executables are not distributed; the program has to be compiled and linked, eg with GNU's gfortran.
    Please report any error you may happen to find.

  • Latest version: qgraf-3.3 (July 2018).
    The features added since the release of version 3.1.4 include:
    increased performance in some ‘extreme’ cases (3.1.5);
    option “onshellx”, an extended form of “onshell” (3.2);
    a way of restricting the configuration of external lines (3.3);
    the ability to require/disallow bridge-type propagators with certain momenta (3.3);
    improved treatment of duplicate vertices (3.3).

  • A note to software developers:
    qgraf-3.4, which should be available by the end of 2018, will be the next ‘stable’ version
    (ie available for a long period, minimal fixes if need be).

The diagram generation is based on the algorithm described in the following article:

  • Automatic Feynman graph generation
    P. Nogueira
    J. Comput. Phys. 105 (1993) 279-289