We present GM2Calc, a public C++ program for the calculation of MSSM
contributions to the anomalous magnetic moment of the muon, (g−2)μ. The
code computes (g−2)μ precisely, by taking into account the latest two-loop
corrections and by performing the calculation in a physical on-shell
renormalization scheme. In particular the program includes a tanβ
resummation so that it is valid for arbitrarily high values of tanβ, as
well as fermion/sfermion-loop corrections which lead to non-decoupling effects
from heavy squarks. GM2Calc can be run with a standard SLHA input file,
internally converting the input into on-shell parameters. Alternatively, input
parameters may be specified directly in this on-shell scheme. In both cases the
input file allows one to switch on/off individual contributions to study their
relative impact. This paper also provides typical usage examples not only in
conjunction with spectrum generators and plotting programs but also as C++
subroutines linked to other programs.Comment: 27 pages, 4 figures, 4 listings; version sent to EPJ