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تسجيل مستخدم جديدComparative computational results for some vertex and facet enumeration codes
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We report some computational results comparing parallel and sequential codes for vertex/facet enumeration problems for convex polyhedra. The problems chosen span the range from simple to highly degenerate polytopes. We tested one code (lrs) based on pivoting and four codes (cddr+, ppl, normaliz, PORTA) based on the double description method. normaliz employs parallelization as do the codes plrs and mplrs which are based on lrs. We tested these codes using various hardware configurations with up to 1200 cores. Major speedups were obtained by parallelization, particularly by the code mplrs which uses MPI and can operate on clusters of machines.
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We describe a new parallel implementation, mplrs, of the vertex enumeration code lrs that uses the MPI parallel environment and can be run on a network of computers. The implementation makes use of a C wrapper that essentially uses the existing lrs c
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