Elsevier Science Home
Computer Physics Communications Program Library
Full text online from Science Direct
Programs in Physics & Physical Chemistry
CPC Home

[Licence| Download | New Version Template] abhr_v1_0.gz(8 Kbytes)
Manuscript Title: A fast vectorized program for the Cyber 205 to calculate the partition function of the 3-D Ising model.
Authors: P.A. Carter
Program title: MICRO
Catalogue identifier: ABHR_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 54(1989)103
Programming language: Fortran.
Computer: CDC CYBER 205.
Operating system: CDC CYBER 205 SERIES 642, VSOS 2.2.
Word size: 64
Peripherals: disc.
Keywords: Three-d ising model, Zeros of Partition function, Multi-spin coding, Statistical physics, Thermodynamics.
Classification: 23.

Nature of problem:
The density of states for each energy is estimated by finding the relative frequencies of each energy using a microcanonical approach.

Solution method:
The program uses a set of 64 * VLEN lattices to increase the efficiency of the algorithm. The lattices are stored using multi-spin coding and the lattice is updated by logical operations. The user specifies a set of four consecutive energies for which the program estimates the relative population of states. The program updates the lattices at 110 million spin flips per second with a resonable vector length.