mat2betti(Matrix,ZZ) -- matrix to Betti diagram

• Function: mat2betti

• Usage:

  mat2betti(M,lowDegree)

  mat2betti M

• Inputs:
  • M, a matrix, A matrix of Betti numbers: each row corresponds to a slanted degree
  • lowDegree, an integer, default value is 0
• Outputs:
  • a Betti tally

i1 : M = matrix"1,0,0,0;0,3,0,0;0,0,5,3"

o1 = | 1 0 0 0 |
     | 0 3 0 0 |
     | 0 0 5 3 |

              3       4
o1 : Matrix ZZ  <-- ZZ

i2 : mat2betti M

            0 1 2 3
o2 = total: 1 3 5 3
         0: 1 . . .
         1: . 3 . .
         2: . . 5 3

o2 : BettiTally

i3 : mat2betti(M,3)

            0 1 2 3
o3 = total: 1 3 5 3
         3: 1 . . .
         4: . 3 . .
         5: . . 5 3

o3 : BettiTally