Forms an interval, lower..upper, of a doubly infinite free resolution of a a Cohen-Macaulay module over a Gorenstein ring, such as any module over an exterior algebra (actually, any module over any ring.)
i1 : E = ZZ/101[a,b,c, SkewCommutative=>true] o1 = E o1 : PolynomialRing, 3 skew commutative variables |
i2 : M = coker map(E^2, E^{-1}, matrix"ab;bc")
o2 = cokernel | ab |
| bc |
2
o2 : E-module, quotient of E
|
i3 : presentation M
o3 = | ab |
| bc |
2 1
o3 : Matrix E <--- E
|
i4 : TateResolution(M,-2,7)
9 5 2 1 2 4 7 11 16 22
o4 = E <-- E <-- E <-- E <-- E <-- E <-- E <-- E <-- E <-- E <-- 0
-2 -1 0 1 2 3 4 5 6 7 8
o4 : ChainComplex
|
In a previous version of this script, this command returned a betti table; now use "betti TateResolution" instead.
The object TateResolution is a method function.