toricGraverDegrees(A)
Equivalent to "output --degrees foo.gra" in 4ti2. Very often the Graver basis consists of too many binomials, and one is only interested in their degrees. In this case, instead of looking at the Graver basis of $I_A$, we may just want to look for the degrees of binomials which show up:
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Note that these are all 1-norms of the vectors. Since $I_A$ is homogeneous, there are 3 binomials of degree 2 (norm 4) and 2 binomials of degree 3 (norm 6).
Here is a more complicated example, where one may not want to see the Graver basis elements explicitly. The toric ideal I_M is the ideal of the rational normal scroll S(3,2,3):
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Here is another example where with many Graver basis elements. The following matrix is a design matrix for a particular statistical model for a 4-node p1 network; see Fienberg-Petrovic-Rinaldo.
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The object toricGraverDegrees is a method function with options.