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GB.GetRes
Syntax
GB.GetRes(M:IDEAL or MODULE):TAGGED("$cocoa/gb.Res")
Summary
returns the resolution computed so far
Description
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.

Example

Use R ::= Q[txyz];
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)
-------------------------------
See also: