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returns the resolution computed so far
$gb.GetRes(M:IDEAL or MODULE):TAGGED("$gb.Res")
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This function returns the part of the resolution of M computed so
far. It does not compute the resolution of M as does
Res
, rather,
GB.GetRes is intended primarily to be used within the Interactive
Groebner Framework. Thus, for example,
GB.GetRes may be used to
examine the resolution as it is computed, one step at a time.
Use R ::= QQ[t,x,y,z];
I := Ideal(x^2-yt,xy-zt,xy);
$gb.Start_Res(I); -- start Interactive Groebner Framework
$gb.Step(I); -- take one step in calculation of resolution
$gb.GetRes(I); -- the resolution so far
0 --> R(-2)
-------------------------------
$gb.Step(I); -- one more step
$gb.GetResLen(I); -- the computed resolution still has length 1
1
-------------------------------
$gb.GetBettiMatrix(I); -- the Betti Matrix so far
----
----
0
2
----
-------------------------------
$gb.GetRes(I);
0 --> R^2(-2)
-------------------------------
$gb.Steps(I,5); -- five more steps
$gb.GetRes(I);
0 --> R(-4) --> R^3(-2)
-------------------------------
$gb.Complete(I); -- complete the calculation
$gb.GetResLen(I);
3
-------------------------------
$gb.GetBettiMatrix(I);
--------------
--------------
0 0 0
0 0 3
0 0 0
0 4 0
2 0 0
--------------
-------------------------------
$gb.GetRes(I);
0 --> R^2(-5) --> R^4(-4) --> R^3(-2)
-------------------------------
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