Program package for multicanonical simulations of U(1) lattice gauge theory—Second version

Abstract

A new version STMCMUCA_V1_1 of our program package is available. It eliminates compatibility problems of our Fortran 77 code, originally developed for the g77 compiler, with Fortran 90 and 95 compilers. New version program summaryProgram title: STMC_U1MUCA_v1_1Catalogue identifier: AEET_v1_1Licensing provisions: Standard CPC license, http://cpc.cs.qub.ac.uk/licence/licence.htmlProgramming language: Fortran 77 compatible with Fortran 90 and 95Computers: Any capable of compiling and executing Fortran codeOperating systems: Any capable of compiling and executing Fortran codeRAM: 10 MB and up depending on lattice size usedNo. of lines in distributed program, including test data, etc.: 15059No. of bytes in distributed program, including test data, etc.: 215733Keywords: Markov chain Monte Carlo, multicanonical, Wang–Landau recursion, Fortran, lattice gauge theory, U(1) gauge group, phase transitions of continuous systemsClassification: 11.5Catalogue identifier of previous version: AEET_v1_0Journal Reference of previous version: Computer Physics Communications 180 (2009) 2339–2347Does the new version supersede the previous version?: YesNature of problem:Efficient Markov chain Monte Carlo simulation of U(1) lattice gauge theory (or other continuous systems) close to its phase transition. Measurements and analysis of the action per plaquette, the specific heat, Polyakov loops and their structure factors.Solution method:Multicanonical simulations with an initial Wang–Landau recursion to determine suitable weight factors. Reweighting to physical values using logarithmic coding and calculating jackknife error bars.Reasons for the new version:The previous version was developed for the g77 compiler Fortran 77 version. Compiler errors were encountered with Fortran 90 and Fortran 95 compilers (specified below).Summary of revisions:epsilon=one/10**10 is replaced by epsilon/10.0D10 in the parameter statements of the subroutines u1_bmha.f, u1_mucabmha.f, u1wl_backup.f, u1wlread_backup.f of the folder Libs/U1_par. For the tested compilers script files are added in the folder ExampleRuns and readme.txt files are now provided in all subfolders of ExampleRuns. The gnuplot driver files produced by the routine hist_gnu.f of Libs/Fortran are adapted to syntax required by gnuplot version 4.0 and higher.Restrictions:Due to the use of explicit real*8 initialization the conversion into real*4 will require extra changes besides replacing the implicit.sta file by its real*4 version.Unusual features:The programs have to be compiled the script files like those contained in the folder ExampleRuns as explained in the original paper.Running time:The prepared test runs took up to 74 minutes to execute on a 2 GHz PC.