Description
sum C -- yields the sum of the modules in a chain complex map.
The degrees of the components are preserved.
i1 : R = ZZ/101[a..c];
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i2 : C = res coker vars R
1 3 3 1
o2 = R <-- R <-- R <-- R <-- 0
0 1 2 3 4
o2 : ChainComplex
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i3 : sum C.dd
o3 = {0} | 0 a b c 0 0 0 0 |
{1} | 0 0 0 0 -b -c 0 0 |
{1} | 0 0 0 0 a 0 -c 0 |
{1} | 0 0 0 0 0 a b 0 |
{2} | 0 0 0 0 0 0 0 c |
{2} | 0 0 0 0 0 0 0 -b |
{2} | 0 0 0 0 0 0 0 a |
{3} | 0 0 0 0 0 0 0 0 |
8 8
o3 : Matrix R <-- R
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i4 : betti oo
0 1
o4 = total: 8 8
-1: . 1
0: 1 3
1: 3 3
2: 3 1
3: 1 .
o4 : BettiTally
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