jacobi_openmp, a FORTRAN90 code which uses the OpenMP application program interface to parallelize a Jacobi iteration solving A*x=b.
Each step of the Jacobi iteration produces a vector xnew. The i-th entry of xnew is found by ``solving'' the i-th linear equation for the i-th variable. This operation can be done in parallel. It is a little more complicated to compute the maximum difference between the old and new x values, and to compute the maximum residual, but these can be done.
The example uses a standard -1,2,-1 matrix which has very slow convergence. Here, the point is not so much to get the answer, but to show that the process can be speeded up by employing OpenMP.
The computer code and data files described and made available on this web page are distributed under the MIT license
jacobi_openmp is available in a C version and a C++ version and a FORTRAN90 version.
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FFT_OPENMP, a FORTRAN90 code which demonstrates the computation of a Fast Fourier Transform in parallel, using OpenMP.
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MD_OPENMP, a FORTRAN90 code which carries out a molecular dynamics simulation using OpenMP.
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MXM_OPENMP, a FORTRAN90 code which computes a dense matrix product C=A*B, using OpenMP for parallel execution.
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POISSON_OPENMP, a FORTRAN90 code which computes an approximate solution to the Poisson equation in a rectangle, using the Jacobi iteration to solve the linear system, and OpenMP to carry out the Jacobi iteration in parallel.
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QUAD_OPENMP, a FORTRAN90 code which approximates an integral using a quadrature rule, and carries out the computation in parallel using OpenMP.
QUAD2D_OPENMP, a FORTRAN90 code which applies a product quadrature rule to estimate an integral over a 2D rectangle, using OpenMP for parallel execution.
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SATISFY_OPENMP, a FORTRAN90 code which demonstrates, for a particular circuit, an exhaustive search for solutions of the circuit satisfiability problem, using OpenMP for parallel execution.
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SGEFA_OPENMP, a FORTRAN90 code which reimplements the SGEFA/SGESL linear algebra routines from LINPACK for use with OpenMP.
SUPERLU_OPENMP, FORTRAN90 codes which illustrate how to use the SUPERLU library with the OpenMP parallel programming interface, which applies a fast direct solution method to solve sparse linear systems, by James Demmel, John Gilbert, and Xiaoye Li.
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