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CompleteIntersectionResolutions :: isQuasiRegular

isQuasiRegular -- tests a matrix or sequence or list for quasi-regularity on a module

Synopsis

Description

ff is quasi-regular if the length of ff is <= dim M and the annihilator of ff_i on M/(ff_0..ff_{(i-1))}M has finite length for all i=0..(length ff)-1.

i1 : kk=ZZ/101;
i2 : S = kk[a,b,c];
i3 : E = S^1/ideal"ab"++S^1/ideal vars S;
i4 : f1 =matrix"a";

             1       1
o4 : Matrix S  <--- S
i5 : f2 =matrix"a+b,c";

             1       2
o5 : Matrix S  <--- S
i6 : f3 = matrix"a+b";

             1       1
o6 : Matrix S  <--- S
i7 : f4 = matrix"a+b, a2+b";

             1       2
o7 : Matrix S  <--- S
i8 : isQuasiRegular(f1,E)

o8 = false
i9 : isQuasiRegular(f2,E)

o9 = true
i10 : isQuasiRegular(f3,E)

o10 = true
i11 : isQuasiRegular(f4,E)

o11 = false

Ways to use isQuasiRegular :

For the programmer

The object isQuasiRegular is a method function.