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Unusual Linear Equation Solver

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Contact: F.X.Timmes
my one page vitae,
full vitae,
research statement, and
teaching statement.

The source code in gift.tbz writes source code to solve a system of linear equations by Gaussian elimination. It is setup for a 10x10 tridiagonal matrix. Gift-generated routines skip calculations with matrix elements that are zero; in this restricted sense gift-generated routines are sparse, but the storage of a full matrix is still required. Diagonal dominance is assumed, so no row or column interchanges are performed. The tool writes out the sequence of Gaussian elimination and backsubstitution steps without any do loop constructions over the matrix elements (see the snippet elow) Thus, gift generated subroutines can become quite large. However, for small matrices the execution speed of the generated subroutines on nuclear reaction networks is faster than any of the dense or sparse packages that I've tested.


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