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