Public Domain Software: Conjugate Gradient


A Set of Conjugate Gradient Routines for Real and Complex Arithmetics.

by   V. Frayssé    L. Giraud

Last Release: Jan 2003 - Version 1.1
We propose an implementation of the Conjugate Gradient (CG) algorithm for real and complex, single and double precision arithmetics suitable for serial, shared memory and distributed memory computers. For the sake of simplicity, flexibility and efficiency, the CG solvers have been implemented using the reverse communication mechanism for the matrix-vector product, the preconditioning and the dot product computations. The code is written in Fortran 77. Finally the implemented stopping criterion is based on a normwise backward error.  Click here to download the User's Guide in postscript (Gzipped PostScript 67 KB) or pdf format.
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Last Update: Oct 24, 2002