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<TITLE>4ti2 -- Computation of Hilbert bases, Graver bases, toric Groebner bases, and more</TITLE>
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    <font size=6>Data format</font>
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The interface of 4ti2 is minimalistic: A project is defined via a set
of text files with the same basename and different extensions, most
importantly the file 'foo.mat' containing the problem matrix.  Each of
the files has a very simple format,

Computed sets such as a Graver basis or a Markov basis are then written
into files 'foo.gra' and 'foo.mar', respectively.<p>

Input files and output files usually contain a matrix or a list of
vectors (written as a matrix) in a standard encoding such as<br>
<pre>
2 4
1 1 1 1
1 2 3 4
</pre><p>
There are only few exceptions, for example in a file
'foo.vars' containing user specified variable names:<br>
<pre>
3
a b x
</pre>

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