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Macaulay2 / M2

The primary source code repository for Macaulay2, a system for computing in commutative algebra, algebraic geometry and related fields.
https://macaulay2.com
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lyubeznikResolution bug #3480

Open sterns opened 1 week ago

sterns commented 1 week ago

In the simplicial Complexes package if the lyubeznikResolution function is passed a monomialIdeal that has 6 or more minimal generators an index error occurs. It seems the issue stems from the following lines in M2/Macaulay2/packages/SimplicialComplexes/Code.m2

841    MinGens := flatten entries mingens I; 
842    MO := opts.MonomialOrder;
843    R := QQ(monoid[vars(0..#(mingens I)-1)]);

In the last line # is applied to the matrix mingens I. This always returns 5, the number of keys in the dictionary used to store matrices. This can be fixed by replacing line 843 with R := QQ(monoid[vars(0..#(MinGens)-1)]); which instead uses the local variable MinGens.

d-torrance commented 1 week ago

Great catch! Would you like to open a pull request with the fix?