WIGXJPF library and program

General Information

WIGXJPF evaluates Wigner 3j, 6j and 9j symbols accurately using prime factorisation and multi-word integer arithmetic.

Type

Scientific software, program package

Language

Program: C. Library interfaces: C, Fortran, Python

License

WIGXJPF is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
WIGXJPF is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with WIGXJPF. If not, see http://www.gnu.org/licenses/.

Main developer

Håkan T. Johansson, Chalmers University of Technology, Sweden

Distributor

Nuclear theory and few-body physics group, Chalmers University of Technology, Sweden

Acknowledgment

The research leading to these results has received funding from the European Research Council under the European Community's Seventh Framework Programme (FP7/2007-2013) / ERC grant agreement no. 240603, and the Swedish Foundation for International Cooperation in Research and Higher Education (STINT, IG2012-5158).

Reference

The recommended way to refer to WIGXJPF, when used for computations that are published in a research article, is to cite the following paper:
H. T. Johansson and C. Forssén, Fast and Accurate Evaluation of Wigner 3j, 6j, and 9j Symbols Using Prime Factorization and Multiword Integer Arithmetic, SIAM J. Sci. Comput., 38(1) (2016), A376-A384. eprint http://dx.doi.org/10.1137/15M1021908
Pre-print (2015) at arXiv:1504.08329

Download

Location

http://fy.chalmers.se/subatom/wigxjpf/wigxjpf-1.13.tar.gz

Contact

Håkan T. Johansson (f96hajo@chalmers.se) and Christian Forssén (christian.forssen@chalmers.se)

Version

1.13 (CHANGELOG)

Support

No formal support

Alternatives

Library for fast lookup: FASTWIGXJ.
(If your program uses very many symbols; trades memory for speed - factor 10+.)

Documentation

See README (included with download).

A short slide-show presentation.

Some usage statistics.

Examples

Symbol evaluation

Symbols can be evaluated directly from the command-line after download and unpacking (half integer arguments are given on decimal form, e.g. ½ as 0.5):

make
bin/wigxjpf --6j=2,2,1,2,1,1

C interface usage

Compile with -Ipath-to-wigxjpf/inc/ and link with -Lpath-to-wigxjpf/lib/ -lwigxjpf (note that the evaluation functions take 2* the angular momenta arguments as integers).

#include "wigxjpf.h"

int main()
{
  double val6j;

  wig_table_init(2*100, 9);
  wig_temp_init(2*100);

  val6j = wig6jj(2*  2 , 2*  2 , 2*  1 ,
                 2*  2 , 2*  1 , 2*  1 );

  wig_temp_free();
  wig_table_free();

  return 0;
}

Python interface usage

Either compile locally:

make pywigxjpf_ffi

or install pywigxjpf directly from PyPI:

pip install pywigxjpf

Example usage:

import pywigxjpf as wig

wig.wig_table_init(10, 9)
wig.wig_temp_init(10)

wig.wig6jj(2*  2 , 2*  2 , 2*  1 ,
           2*  2,  2*  1 , 2*  1 )

MATLAB usage

tar --transform 's/wigxjpf-[0-9.]*/wigxjpf/' -zxf wigxjpf-latest.tar.gz

Last modified: Mon 22 Feb 00:17:30 CET 2021