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BettiMatrix

the matrix of the graded Betti numbers

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

Description
This function returns the Betti matrix for M.

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)
-------------------------------
  BettiMatrix(I);
--------------
               
--------------
   0    0    0 
   0    0    3 
   0    0    0 
   0    4    0 
   2    0    0 
--------------

-------------------------------
  Untagged(BettiMatrix(I));
Mat([
  [0, 0, 0],
  [0, 0, 3],
  [0, 0, 0],
  [0, 4, 0],
  [2, 0, 0]
])
-------------------------------


See Also