satisfy_mpi, a C code which demonstrates, for a particular circuit, an exhaustive search for solutions of the circuit satisfy problem. This version of the code uses MPI to carry out the solution in parallel.
This problem assumes that we are given a logical circuit of AND, OR and NOT gates, with N binary inputs and a single output. We are to determine all inputs which produce a 1 as the output.
The general problem is NP complete, so there is no known polynomial-time algorithm to solve the general case. The natural way to search for solutions then is exhaustive search.
In an interesting way, this is a very extreme and discrete version of the problem of maximizing a scalar function of multiple variables. The difference is that here we know that both the input and output only have the values 0 and 1, rather than a continuous range of real values!
This problem was a natural candidate for parallel computation, since the individual evaluations of the circuit are completely independent.
The computer code and data files made available on this web page are distributed under the GNU LGPL license.
satisfy_mpi is available in a C version and a C++ version and a FORTRAN90 version.
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