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ranks -- display the ranks of an OI-resolution

Description

Given an OI-resolution $C$, this method displays the ranks of the modules in $C$.

i1 : P = makePolynomialOIAlgebra(2, x, QQ);
 
i2 : F = makeFreeOIModule(e, {1,1}, P);
 
i3 : installGeneratorsInWidth(F, 2);
 
i4 : b = x_(1,2)*x_(1,1)*e_(2,{2},1)+x_(2,2)*x_(2,1)*e_(2,{1},2);
 
i5 : C = oiRes({b}, 2)

o5 = 0: (e0, {2}, {-2})
     1: (e1, {4}, {-4})
     2: (e2, {5, 5, 5}, {-5, -5, -5})

o5 : OIResolution
 
i6 : ranks C

o6 = 0: rank 1
     1: rank 1
     2: rank 3

Ways to use ranks:

  • ranks(OIResolution)

For the programmer

The object ranks is a method function.

The source of this document is in OIGroebnerBases.m2:2771:0.