NAME

       gfan - tool to compute Gröbner fans and tropical varieties

SYNOPSIS

       gfan_tool [options]

       gfan _tool [options]

DESCRIPTION

       Gfan  is a software package for computing Gröbner fans and tropical varieties.  These are polyhedral fans
       associated to polynomial ideals. The maximal cones of a Gröbner fan are  in  bijection  with  the  marked
       reduced Gröbner bases of its defining ideal. The software computes all marked reduced Gröbner bases of an
       ideal. Their union is a universal Gröbner basis. The tropical variety of a polynomial ideal is a  certain
       subcomplex of the Gröbner fan. Gfan contains algorithms for computing this complex for general ideals and
       specialized algorithms for tropical curves,  tropical  hypersurfaces  and  tropical  varieties  of  prime
       ideals.  In  addition to the above core functions the package contains many tools which are useful in the
       study of Gröbner bases, initial ideals and tropical geometry.

       The complete list of tools is:

       bases, buchberger, combinerays, doesidealcontain, fancommonrefinement, fanhomology, fanlink,  fanproduct,
       fansubfan,  genericlinearchange,  groebnercone,  groebnerfan, homogeneityspace, homogenize, initialforms,
       interactive, ismarkedgroebnerbasis, krulldimension, latticeideal, leadingterms, list,  markpolynomialset,
       minkowskisum,  minors,  mixedvolume,  overintegers,  padic,  polynomialsetunion, render, renderstaircase,
       saturation,  secondaryfan,  stats,  substitute,  symmetries,  tolatex,  topolyhedralfan,   tropicalbasis,
       tropicalbruteforce,  tropicalevaluation,  tropicalfunction,  tropicalhypersurface,  tropicalintersection,
       tropicallifting,   tropicallinearspace,   tropicalmultiplicity,    tropicalrank,    tropicalstartingcone,
       tropicaltraverse, tropicalweildivisor, version.

       Below  are  presented the generic options available with all tools. For specific options of a given tool,
       we refer to the help message of that tool.

OPTIONS

       --help Display a help message describing the  functionality  of  gfan_tool  and  the  available  specific
              options.

       --log1, --log2...
              Tell  Gfan  how  much information to write to standard error while a computation is running. These
              options are very useful when you wish to know if Gfan is making any progress in its computation.

       --stdin value
              Specify a file to use as input instead of reading from the standard input.

       --stdout value
              Specify a file to write output to instead of writing to the standard output.

       --xml  Let polyhedral fans be output in an XML format instead of in the text format. (The XML  files  are
              not readable by Gfan.)

SEE ALSO

       The    complete    manual    of    Gfan    is    available    from    the   website   of   the   project:
       http://home.imf.au.dk/jensen/software/gfan/gfan.html