Opened 5 years ago
Closed 5 years ago
#19065 closed defect (fixed)
A few fixes and enhancements for chain complex morphisms
Reported by:  jhpalmieri  Owned by:  

Priority:  major  Milestone:  sage6.9 
Component:  algebraic topology  Keywords:  
Cc:  tscrim  Merged in:  
Authors:  John Palmieri  Reviewers:  Travis Scrimshaw 
Report Upstream:  N/A  Work issues:  
Branch:  94e08a7 (Commits)  Commit:  94e08a7d1d7fefdbee992f01604cc48677a70ea2 
Dependencies:  Stopgaps: 
Description
This ticket addresses several issues:
 when defining chain complex morphisms, we don't check the size of the defining matrices, and we should.
 the
__mul__
method multiplies the factors in the wrong order.
 it may be useful to have an
in_degree
method:f.in_degree(5)
will return the matrix definingf
in degree 5.
Change History (7)
comment:1 Changed 5 years ago by
 Branch set to u/jhpalmieri/chains
comment:2 Changed 5 years ago by
 Commit set to 45e2206b323ad222e818be931a9e77a4a213b14c
 Status changed from new to needs_review
comment:3 Changed 5 years ago by
 Reviewers set to Travis Scrimshaw
It looks like you also fixed a bug if there was a mismatch in the matrix dictionaries (which would result it a KeyError
being thrown). Do you think you could also add a test for this? If this could never happen, then I'd revert back to directly calling x._matrix_dictionary[i]
Could you also make this doc tweak:
"""  The matrix representing this morphism in degree n + The matrix representing this morphism in degree `n`. INPUT:   ``n``  degree +  ``n``  degree
If you make those changes and the patchbot approves, then you can set this as a positive review on my behalf. Thanks.
comment:4 Changed 5 years ago by
Good idea. In fact, this led me to find another bug (in the "product" self * x
, we need to check that self._domain == x._codomain
, not self._codomain == x._domain
).
comment:5 Changed 5 years ago by
 Commit changed from 45e2206b323ad222e818be931a9e77a4a213b14c to 94e08a7d1d7fefdbee992f01604cc48677a70ea2
Branch pushed to git repo; I updated commit sha1. New commits:
94e08a7  trac 19065: one more bug fix plus a doctest

comment:6 Changed 5 years ago by
 Status changed from needs_review to positive_review
comment:7 Changed 5 years ago by
 Branch changed from u/jhpalmieri/chains to 94e08a7d1d7fefdbee992f01604cc48677a70ea2
 Resolution set to fixed
 Status changed from positive_review to closed
New commits:
trac 19065: fix some issues with chain complex morphisms.