Solvers for systems with few monomials in PHCv2.3.21

Systems with exactly two monomials in every equation are called "binomial".
Systems with no more than n+1 monomials (eventually after division) are
called "fewnomial".  Because of this extreme sparsity, we can solve such
system much more efficiently than general polynomial systems.

This directory was introduced in release 2.3.06 to organize the new code
which resulted from a bug fix.  Improved numerical stability in v2.3.07.
Detected zero components in the intermediate y vector in v2.3.16.

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file name                        : short description
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standard_binomial_systems        : parsing and evaluation of binomial systems
standard_radial_solvers          : compute radius of roots of binomial system
standard_binomial_solvers        : solve binomial systems standard arithmetic
ts_binwit                        : test witness sets for binomial systems
standard_fewnomial_systems       : parsing and evaluation of fewnomial systems
standard_fewnomial_solvers       : solving fewnomial systems
ts_fewsys                        : test program on fewnomial systems
standard_sparse_solvers          : parsing and solving fewnomial systems
ts_spasol                        : simple test routine on sparse solvers
black_box_fewnomial_solvers      : as called by main program
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