  A set of programs is presented for automatically generating and calculating
Feynman diagrams. Diagrams are generated with FeynArts, then algebraically
simplified using a combination of Mathematica and FORM implemented in the
package FormCalc, and finally evaluated numerically using the LoopTools
package. FormCalc works either in dimensional regularization or in constrained
differential renormalization, the latter of which is equivalent at the one-loop
level to regularization by dimensional reduction. FormCalc combines the speed
of FORM with the powerful instruction set of Mathematica, and the latter
greatly eases further processing of the results (e.g. selecting or modifying
terms). The output is in a form well suited for numerical evaluation, which is
then straightforward using the implementations of the one-loop integrals in
LoopTools.
