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Induced morphism on unreduced homology and relative homology From the documentation, it is clear how to get the induced

Induced morphism on unreduced homology and relative homology From the documentation, it is clear how to get the induced

Induced morphism on unreduced homology and relative homology From the documentation, it is clear how to get the induced

A stupid question since I do not work with sage a lot - is the right way to do this to install the development version o

I am trying to compute a morphism between chain complexes (and homology/cohomology ultimately) that is induced by a simplicial map. The problem seems to be when I try to specify the map between barycentric subdivisions.

As a concrete example - this works:

S = SimplicialComplex([[1,2]],is_mutable=False)
T = SimplicialComplex([[1,2],[2,3],[1,3]],is_mutable=False)
f = {x[0]:x[0] for x in S.cells()[0]}
H  = Hom(S,T)
z = H(f)
r = z.associated_chain_complex_morphism()

If I try to do the same with the subdivision - I get

S = SimplicialComplex([[1,2]],is_mutable=False).barycentric_subdivision()
S.set_immutable()
T = SimplicialComplex([[1,2],[2,3],[1,3]],is_mutable=False).barycentric_subdivision()
T.set_immutable()
f = {x[0]:x[0] for x in S.cells()[0]}
H  = Hom(S,T)
z = H(f)
r = z.associated_chain_complex_morphism()

I get:

ValueError: matrices must define a chain complex morphism

Any insight would be helpful.

chain morphism between subdivisions I am trying to compute a morphism between chain complexes (and homology/cohomology u