MGGHAT Version 1.1

MGGHAT (MultiGrid Galerkin Hierarchical Adaptive Triangles) is a FORTRAN program for the solution of general second order linear self-adjoint elliptic partial differential equations with Dirichlet, natural or mixed boundary conditions on 2D polygonal domains (possibly with holes).

MGGHAT uses a finite element method with linear, quadratic or cubic elements (user selectable) over triangles. The adaptive refinement via newest vertex bisection and the multigrid iteration are both based on a hierarchical basis formulation. Run time and a posteriori graphical displays are made with gnuplot.

Several changes have been made since version 1.0. It now has the capability to save the program state and evaluate the solution from the saved state. This is useful for systems of equations, time dependent problems, nonlinear equations, etc. Examples for a system of equation and a time dependent problem are included. All graphics are now done with gnuplot. A Tcl/Tk based menu has been added for manipulation of the graphics.

An example driver program for solving Poisson's equation with mixed boundary conditions is available. You can also view the printed output from running this example, and a screendump showing an example of the graphics.

You can learn more about the methods used in MGGHAT by reading ``Unified multilevel adaptive finite element methods for elliptic problems'' (pdf, 260K).

The MGGHAT software is available as a single gzipped tar file (300K), or as three parts (source, documentation and graphics examples) from netlib.

The MGGHAT User's Guide, NISTIR 5948, is available in gzipped postscript (250k).

MGGHAT is in the public domain and not subject to copyright. Please see the LICENSE file.

Development status: Not Maintained
Last change to this page: March 16, 2018
Date this page created: 1997
Contact: William Mitchell
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