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GB.GetBettiMatrix
Syntax
GB.GetBettiMatrix(M:IDEAL or MODULE):TAGGED("$cocoa/io.Matrix")
Summary
returns the Betti matrix computed so far
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: