An extended version of the simple and fast Feynman diagram generator EasyFeynDiag

Abstract The main improvement in this version of EasyFeynDiag is to prohibit equivalent Feynman diagrams to two-loop order (while the previous version is to one-loop). The symmetry factor calculation with equivalent diagrams prohibition to two-loop is a nontrivial problem, which is well solved in the new program. The code of the program is also reorganized, hopefully in a way more convenient for people to read. Title of program: EasyFeynDiag Catalogue Id: AEPD_v2_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)