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Manuscript Title: FlowPy - a numerical solver for functional renormalization group equations
Authors: Thomas Fischbacher, Franziska Synatschke-Czerwonka
Program title: FlowPy
Catalogue identifier: AEPB_v1_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 184(2013)1931
Programming language: Python, C.
Computer: PC or workstation.
Operating system: Unix.
RAM: approx. 40 MB
Keywords: Functional Renormalization Group Equations, Momentum dependent flow equations.
PACS: 11.10.Gh, 11.10.Hi.
Classification: 4.12, 11.1.

External routines: Python, libpython, SciPy, NumPy, python-simpleparse.

Nature of problem:
In the study of functional renormalization group equations non-local integro-differential equations arise which furthermore can contain singular coefficient functions for the highest derivative and may only be given implicitly. Solving these equations beyond the simplest cases thus provides a numerical challenge.

Solution method:
A combination of numerical differentiation, integration, interpolation, and ODE solving.

Restrictions:
Due to the nature of FRG problems, computational effort (run time) will scale quadratically with the number of discretization points. Using more than at most a few hundred discretization points may be impractical.

Running time:
For the SUSY_QM example: ~ 10 seconds for 10 support points, ~ 5 minutes for 100 discretization points. For the momentum_dependent_wavefunction example: ~ 40 minutes for 5 discretization points.