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NormalToricVarieties :: isDegenerate

isDegenerate -- whether a toric variety is degenerate

Synopsis

Description

A d-dimensional normal toric variety is degenerate if its rays do not span d. For example, projective spaces and Hirzebruch surfaces are not degenerate.
i1 : isDegenerate projectiveSpace 3

o1 = false
i2 : isDegenerate hirzebruchSurface 7

o2 = false
Although one typically works with non-degenerate toric varieties, not all normal toric varieties are non-degenerate.
i3 : U = normalToricVariety({{4,-1,0},{0,1,0}},{{0,1}});
i4 : isDegenerate U

o4 = true

See also

Ways to use isDegenerate :