  We give numerical integration results for Feynman loop diagrams such as those
covered by Laporta [1] and by Baikov and Chetyrkin [2], and which may give rise
to loop integrals with UV singularities. We explore automatic adaptive
integration using multivariate techniques from the PARINT package for
multivariate integration, as well as iterated in- tegration with programs from
the QUADPACK package, and a trapezoidal method based on a double exponential
trans- formation. PARINT is layered over MPI (Message Passing Interface), and
incorporates advanced parallel/distributed techniques including load balancing
among processes that may be distributed over a cluster or a network/grid of
nodes. Results are included for 2-loop vertex and box diagrams and for sets of
2-, 3- and 4-loop self-energy diagrams with or without UV terms. Numerical
regularization of integrals with singular terms is achieved by linear and
non-linear extrapolation methods.
