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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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Monomial ideals in the exterior algebra #498

Open bhersey1 opened 8 years ago

bhersey1 commented 8 years ago

Why doesn't the method monomialIdeal apply to ideals in the exterior algebra? In particular, the code for (monomialIdeal,Matrix) requires the ambient ring to be commutative.

i26 : monomialIdeal J stdio:32:1:(3): error: expected a commutative ring

DanGrayson commented 8 years ago

You can try commenting out the error message. I tried it and it seems to work:

Macaulay2, version 1.9.1
with packages: ConwayPolynomials, Elimination, IntegralClosure, LLLBases, PrimaryDecomposition, ReesAlgebra, TangentCone

i1 : R = QQ[x,y,z,SkewCommutative =>true]

o1 = R

o1 : PolynomialRing

i2 : monomialIdeal matrix vars R

o2 = monomialIdeal (x, y, z)

o2 : MonomialIdeal of R

i4 : monomialIdeal matrix {{x,y}}

                           2
o4 = monomialIdeal (x, y, z )

o4 : MonomialIdeal of R

i5 : monomialIdeal matrix {{x*y}}

                     2        2   2
o5 = monomialIdeal (x , x*y, y , z )

o5 : MonomialIdeal of R

To find the location of the error message, run errorDepth=0 in advance.