Opened 3 years ago
Closed 2 years ago
#27081 closed enhancement (fixed)
Section for composite maps
Reported by: | soehms | Owned by: | |
---|---|---|---|
Priority: | major | Milestone: | sage-8.9 |
Component: | categories | Keywords: | section map |
Cc: | Merged in: | ||
Authors: | Sebastian Oehms | Reviewers: | Travis Scrimshaw |
Report Upstream: | N/A | Work issues: | |
Branch: | bb25f16 (Commits, GitHub, GitLab) | Commit: | bb25f1664654e85e4eddee8e356dfd8d876b916d |
Dependencies: | Stopgaps: |
Description
Currently, a section
method for the class FormalCompositeMap
is not implemented.
This ticket supplies a section in cases, where all factors of the composite map have section
implemented.
Examples which will be improved are:
sage: P.<x> = QQ[] sage: P.coerce_map_from(ZZ).section() is None True sage: k = GF(47) sage: R.<x> = PolynomialRing(k) sage: R.coerce_map_from(ZZ).section() is None True
Change History (9)
comment:1 Changed 3 years ago by
- Branch set to u/soehms/section_of_composite_map_27081
comment:2 Changed 3 years ago by
- Commit set to 3fd303ece2b1cefc9bcec69e67de88391d7d8038
- Status changed from new to needs_review
comment:3 Changed 3 years ago by
- Milestone changed from sage-8.7 to sage-8.8
Ticket retargeted after milestone closed (if you don't believe this ticket is appropriate for the Sage 8.8 release please retarget manually)
comment:4 Changed 2 years ago by
- Milestone changed from sage-8.8 to sage-8.9
Moving tickets from the Sage 8.8 milestone that have been actively worked on in the last six months to the next release milestone (optimistically).
comment:5 Changed 2 years ago by
- Reviewers set to Travis Scrimshaw
Sorry for letting my review of this take so long. Once these changes are done, then it is a positive review:
- Compute a section map from sections of the factors of self if they have been implemented + Compute a section map from sections of the factors of + ``self`` if they have been implemented.
I would write this with short-circuiting and the reversal already built-in:
sections = [] for m in reversed(self): try: sec = m.section() except TypeError: return None if sec is None: return None sections.append(m) from sage.categories.homset import Hom from sage.categories.sets_with_partial_maps import SetsWithPartialMaps H = Hom(self.codomain(), self.domain(), category=SetsWithPartialMaps()) return FormalCompositeMap(H, sections)
Capitalize the beginning of the .. NOTE::
in polynomial_element.pyx
.
comment:6 Changed 2 years ago by
- Commit changed from 3fd303ece2b1cefc9bcec69e67de88391d7d8038 to bb25f1664654e85e4eddee8e356dfd8d876b916d
comment:7 Changed 2 years ago by
thanks, Travis! I'll be waiting for the patchbot!
comment:9 Changed 2 years ago by
- Branch changed from u/soehms/section_of_composite_map_27081 to bb25f1664654e85e4eddee8e356dfd8d876b916d
- Resolution set to fixed
- Status changed from positive_review to closed
New commits:
27081: initial version