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BettiDiagram

the diagram of the graded Betti numbers
Syntax 

BettiDiagram(M:IDEAL or MODULE):TAGGED("$gb.BettiDiagram")

Description
This function returns the ("Macaulay-style") Betti diagram for M.

Example 
  Use R ::= QQ[t,x,y,z];
  I := Ideal(x^2-yt,xy-zt,xy);
  Res(I);
0 --> R^2(-5) --> R^4(-4) --> R^3(-2)
-------------------------------
  BettiDiagram(I);
        0    1    2
--------------------
 2:     3    -    -
 3:     -    4    2
--------------------
Tot:    3    4    2
-------------------------------
  Untagged(BettiDiagram(I));
Record[Diagram = Mat([
  [3, 0, 0],
  [0, 4, 2]
]), FirstShift = 2]


See Also