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GB.GetBettiMatrix

returns the Betti matrix computed so far

Syntax
GB.GetBettiMatrix(M:IDEAL or MODULE):TAGGED("$io.Matrix")

Description
This function, if used after executing Res(M), prints the Betti matrix for M. Within the Interactive Groebner Framework, in which resolutions may be computed one step at a time, the function returns the Betti matrix for the part of the resolution computed so far. See GB.GetRes for an example.

Example
Use R ::= Q[t,x,y,z];
I := Ideal(x^2-yt,xy-zt,xy);
Res(I);
0 --> R^2(-5) --> R^4(-4) --> R^3(-2)
-------------------------------
GB.GetBettiMatrix(I);
--------------
               
--------------
   0    0    0 
   0    0    3 
   0    0    0 
   0    4    0 
   2    0    0 
--------------

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See Also