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BettiMatrix

the matrix of the graded Betti numbers

Syntax
BettiMatrix(M: IDEAL|MODULE|LISTResolution)

Description
This function returns the Betti matrix for M .

Example
/**/  use R ::= QQ[t,x,y,z];
/**/  I := ideal(x^2-y*t, x*y-z*t, x*y);
/**/  PrintRes(I);
0 --> R^2(-5) --> R^4(-4) --> R^3(-2)
/**/  BettiMatrix(I);
matrix(ZZ,
 [[0, 0, 0],
  [3, 0, 0],
  [0, 0, 0],
  [0, 4, 0],
  [0, 0, 2]])
/**/  PrintBettiMatrix(I);
--   -->  -->   --
    0    0    0
    0    0    3
    0    0    0
    0    4    0
    2    0    0
--   -->  -->   --

See Also