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TateOnProducts :: tallyDegrees

tallyDegrees -- collect the degrees of the generators of the terms in a free complex

Synopsis

Description

Returns for each free module Cd in the complex the result of tally degrees Cd

i1 : S=ZZ/101[x_0..x_1,y_0,z_0,Degrees=>{2:{2,0,0},1:{0,1,0},{0,0,1}}]

o1 = S

o1 : PolynomialRing
i2 : C =res ideal vars S

      1      4      6      4      1
o2 = S  <-- S  <-- S  <-- S  <-- S  <-- 0
                                         
     0      1      2      3      4      5

o2 : ChainComplex
i3 : betti C

            0 1 2 3 4
o3 = total: 1 4 6 4 1
         0: 1 2 1 . .
         1: . 2 4 2 .
         2: . . 1 2 1

o3 : BettiTally
i4 : tallyDegrees C

o4 = (Tally{{0, 0, 0} => 1}, Tally{{0, 0, 1} => 1}, Tally{{0, 1, 1} => 1},
                                   {0, 1, 0} => 1         {2, 0, 1} => 2  
                                   {2, 0, 0} => 2         {2, 1, 0} => 2  
                                                          {4, 0, 0} => 1
     ------------------------------------------------------------------------
     Tally{{2, 1, 1} => 2}, Tally{{4, 1, 1} => 1}, Tally{})
           {4, 0, 1} => 1
           {4, 1, 0} => 1

o4 : Sequence

Ways to use tallyDegrees :