cg, a FORTRAN77 code which implements a simple version of the conjugate gradient (CG) method for solving a system of linear equations of the form A*x=b, suitable for situations in which the matrix A is symmetric positive definite (SPD), having only real, positive eigenvalues.
The computer code and data files made available on this web page are distributed under the GNU LGPL license.
cg is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.
cg_rc, a FORTRAN77 library which implements the conjugate gradient method for solving a symmetric positive definite sparse linear system A*x=b, using reverse communication.
cg_serial, a FORTRAN77 program which a serial version of the NAS Conjugate Gradient (CG) Parallel Benchmark.
sparse_display, a FORTRAN77 library which can read information defining a matrix of numbers and display the sparsity pattern or location of the nonzero elements using gnuplot().
wathen_matrix, a FORTRAN77 library which compares storage schemes (full, banded, sparse triplet) and solution strategies (Linpack full, Linpack banded, conjugate gradient (CG)) for linear systems involving the Wathen matrix, which can arise when solving a problem using the finite element method (FEM).