#17433 closed defect (fixed)
projective point equality fails for quotient base rings
Reported by:  bhutz  Owned by:  bhutz 

Priority:  major  Milestone:  sage6.5 
Component:  algebraic geometry  Keywords:  
Cc:  Merged in:  
Authors:  Ben Hutz  Reviewers:  Joao Alberto de Faria 
Report Upstream:  N/A  Work issues:  
Branch:  660e624 (Commits, GitHub, GitLab)  Commit:  
Dependencies:  Stopgaps: 
Description
Since the coordinates of the points are lifted, the current equality check fails to detect equality over quotient rings. The comparisons need to be done in the base ring.
P.<x,y>=ProjectiveSpace(Zmod(10),1) p1=P(1/3,1) p2=P.point([1,3],False) p1==p2
Change History (15)
comment:1 Changed 6 years ago by
 Branch set to u/bhutz/ticket/17433
 Created changed from 12/02/14 21:16:14 to 12/02/14 21:16:14
 Modified changed from 12/02/14 21:16:14 to 12/02/14 21:16:14
comment:2 Changed 6 years ago by
 Commit set to 41a5b454cb321fc8e5d8fc058b7be77bdf2c6522
comment:3 Changed 6 years ago by
 Commit changed from 41a5b454cb321fc8e5d8fc058b7be77bdf2c6522 to 8e3e894f5f5fac85062f7c035eaf273ca782fa52
Branch pushed to git repo; I updated commit sha1. New commits:
8e3e894  17433: fixed some typos

comment:4 Changed 6 years ago by
 Status changed from new to needs_review
 Summary changed from projective point equality fails for quoteitn base rings to projective point equality fails for quotient base rings
The fix has the coordinate of the points in the base ring. This was true for fields but not for rings (the coordinates of quotient rings were lifted). Now it is consistent and this fixes the equality comparison as well.
comment:5 Changed 6 years ago by
 Status changed from needs_review to positive_review
Looked over the code, everything ran clean on my end
comment:6 Changed 6 years ago by
 Status changed from positive_review to needs_work
Author/reviewer name missing
comment:7 Changed 6 years ago by
Ping Plus a rebase is needed.
comment:8 Changed 6 years ago by
 Commit changed from 8e3e894f5f5fac85062f7c035eaf273ca782fa52 to 15aa61f96defa91781e02ad90f6649544df45d35
Branch pushed to git repo; I updated commit sha1. New commits:
15aa61f  17433: merge in sage.5.beta3

comment:9 Changed 6 years ago by
 Commit changed from 15aa61f96defa91781e02ad90f6649544df45d35 to d208b8bc9ea28c2f499af23ed8751318db5cd348
Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:
d208b8b  17433: merge with sage6.5.beta3

comment:10 Changed 6 years ago by
I thought I did a bad job on the merge since it still wasn't merging with the master. So I backed up one commit and redid the merge. I did resolve what I thought was the conflict in projective_point.py both times...
comment:11 Changed 6 years ago by
 Commit changed from d208b8bc9ea28c2f499af23ed8751318db5cd348 to 73e233bcf25322beb943ea3f9c4157f5f97f01bf
comment:12 Changed 6 years ago by
 Reviewers set to Joao de Faria
 Status changed from needs_work to needs_review
ok. I think I finally have the merge working. I had to split it slightly into two commits.
comment:13 Changed 6 years ago by
 Branch changed from u/bhutz/ticket/17433 to u/tscrim/ticket/17433
 Commit changed from 73e233bcf25322beb943ea3f9c4157f5f97f01bf to 660e6247fa4aaa927b302fb191dd3ed71df05b32
 Status changed from needs_review to positive_review
comment:14 Changed 6 years ago by
 Branch changed from u/tscrim/ticket/17433 to 660e6247fa4aaa927b302fb191dd3ed71df05b32
 Resolution set to fixed
 Status changed from positive_review to closed
comment:15 Changed 6 years ago by
 Commit 660e6247fa4aaa927b302fb191dd3ed71df05b32 deleted
 Reviewers changed from Joao de Faria to Joao Alberto de Faria
Branch pushed to git repo; I updated commit sha1. New commits:
17433: add more examples