A simple algorithm for automatic Feynman diagram generation

Abstract We present an algorithm for automatic Feynman diagram (FD) generation. Derived directly from the definition formula of an FD, the algorithm features first of all a clear concept. Also, it could naturally generate the symmetry factor for each FD. As it is free of complex and tricky operations commonly seen in other FD generation software, the code for this algorithm should always be easy to write. We provide such an implementation in C. This C program is very small, but it is fast and powerful... Title of program: EasyFeynDiag Catalogue Id: AEPD_v1_0 Nature of problem Automatic generation of Feynman diagrams from given interactions, scattering process, and number of loops. Versions of this program held in the CPC repository in Mendeley Data AEPD_v1_0; EasyFeynDiag; 10.1016/j.cpc.2013.03.015 AEPD_v2_0; EasyFeynDiag; 10.1016/j.cpc.2014.08.025 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018)