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Manuscript Title: NumExp: Numerical epsilon expansion of hypergeometric functions
Authors: Zhi-Wei Huang, Jueping Liu
Program title: NumExp
Catalogue identifier: AEPE_v1_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 184(2013)1973
Programming language: Mathematica and/or Python.
Computer: Any computer where Mathematica or Python is running.
Operating system: Linux, Windows.
Keywords: Hypergeometric functions, Expansion, Feynman diagrams.
PACS: 02.30.Gp, 02.30.Mv, 12.38.Bx.
Classification: 4.4, 5, 11.1.

External routines: mpmath library (for Python)

Nature of problem:
Expansion of hypergeometric functions and/or other transcendental functions in a small parameter ε. These expansions are needed in the context of dimensional regularization for loop integrals.

Solution method:
Hypergeometric function is expressed as a Laurent series in the regularization parameter ε, where the coefficients are evaluated numerically by multi-precision finite difference method.

The calculation may be inefficient if the arguments of hypergeometric functions are close to the convergent boundaries.

Running time:
Generally it is less than a few seconds, depending on the complexity of the problem.