Unimodularity of a subdivision
Posted: 24 Apr 2025, 12:49
The following code creates the curve in Example 3.1.8.(3) in the book Introduction to Tropical Geometry by Maclagan-Strumfels:
(check the first curve in the second row of Figure 3.1.2). Moreover, the following code gives its dual subdivision:
This subdivision looks highly unimodular to me, but it's not according to polymake; the code
returns false. Am I doing something stupid again? 
Code: Select all
$mons = [[0,3,0],[0,2,1],[0,1,2],[0,0,3],[1,2,0,],[1,1,1],[1,0,2],[2,1,0],[2,0,1],[3,0,0]];
$vals = [3,1,1,3,1,0,1,1,1,3];
$C = new Hypersurface<Min>(MONOMIALS=>$mons, COEFFICIENTS=>$vals);
$C -> VISUAL;Code: Select all
$ds = $C -> dual_subdivision();
$ds -> VISUAL;
Code: Select all
print $ds -> UNIMODULAR;