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

## Synopsis

• Usage:
tallyDegrees C
• Inputs:
• C, , a complex of graded free modules
• Outputs:
• , a sequence of tallies of the degrees of the generators of the free module

## Description

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

 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 :

• tallyDegrees(ChainComplex)

## For the programmer

The object tallyDegrees is .