Monte Carlo 3D Ising Model

ISING_3D_SIMULATION is a FORTRAN90 program which carries out a Monte Carlo simulation of a 3D Ising model.

The text of this Ising model appeared as an example in the ANSI FORTRAN90 standard in 1992. It is a nice presentation of how to use certain features of FORTRAN90, and also demonstrates why one would like to use these features - they make the Ising calculation very simple to describe.


ising_3d_simulation n iterations
where Note that the user might also want to vary the transition probabilities. This cannot currently be done on the command line, and requires editing the program and recompiling it.


The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.


ISING_3D_SIMULATION is available in a FORTRAN90 version.

Related Data and Programs:

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  1. American National Standard for Programming Language: Fortran - Extended,
    American National Standards Institute, 1992,
    pages 296-299.

Source Code:

Examples and Tests:

SMALL is a run of a small (N=10) model for a short (ITERATIONS = 25) number of iterations.

List of Routines:

You can go up one level to the FORTRAN90 source codes.

Last revised on 30 November 2007.