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+.)
Library for sequence evaluation: WIGSGLL.
(If your program uses sequences of symbols.)

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
Latest version link
wigxjpf-latest.tar.gz

To avoid version numbers in directory name, unpack with:

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

Comments? christian.forssen@chalmers.se

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