heft -- heft vector of ring or monoid

• Usage:

  heft R

• Inputs:
  • R, a ring or a monoid,
• Outputs:
  • a list, a weight co-vector of integers with length the same as degree length of R, or
  • null if there is no heft vector.

i1 : S = QQ[a..d, DegreeRank => 4];

i2 : degrees S

o2 = {{1, 0, 0, 0}, {0, 1, 0, 0}, {0, 0, 1, 0}, {0, 0, 0, 1}}

o2 : List

i3 : heft S

o3 = {1, 1, 1, 1}

o3 : List