Opened 6 years ago
Closed 6 years ago
#18478 closed defect (fixed)
Fix comparison of equal newforms in different parents
Reported by: | pbruin | Owned by: | |
---|---|---|---|
Priority: | minor | Milestone: | sage-6.8 |
Component: | modular forms | Keywords: | newform comparison |
Cc: | vdelecroix, davidloeffler | Merged in: | |
Authors: | Peter Bruin | Reviewers: | David Loeffler |
Report Upstream: | N/A | Work issues: | |
Branch: | 8b6cea1 (Commits) | Commit: | 8b6cea1b82b92af1be73ea29686b8200a0caf4d0 |
Dependencies: | Stopgaps: |
Description
Two newforms that are identical but live in different parents (spaces of cusp forms for Gamma0
versus Gamma1
, or with versus without character) should be regarded as equal, but currently are not:
sage: f = Newforms(Gamma1(11), 2)[0]; f q - 2*q^2 - q^3 + 2*q^4 + q^5 + O(q^6) sage: g = Newforms(Gamma0(11), 2)[0]; g q - 2*q^2 - q^3 + 2*q^4 + q^5 + O(q^6) sage: f == g False
sage: f = Newforms(DirichletGroup(4)[1], 5)[0]; f q - 4*q^2 + 16*q^4 - 14*q^5 + O(q^6) sage: g = Newforms(Gamma1(4), 5)[0]; g q - 4*q^2 + 16*q^4 - 14*q^5 + O(q^6) sage: f == g False
This came up in comment:15:ticket:18061. The current version of the __eq__
method was written in #18068; I did not know about this bug then.
Comparison of modular forms of type ModularFormElement
living in different parents is broken as well (see e.g. comment:9:ticket:18068), but this should probably dealt with on a different ticket, by properly implementing coercion for modular forms.
Change History (3)
comment:1 Changed 6 years ago by
- Branch set to u/pbruin/18478-Newform_comparison
- Commit set to 8b6cea1b82b92af1be73ea29686b8200a0caf4d0
- Status changed from new to needs_review
comment:2 Changed 6 years ago by
- Reviewers set to David Loeffler
- Status changed from needs_review to positive_review
comment:3 Changed 6 years ago by
- Branch changed from u/pbruin/18478-Newform_comparison to 8b6cea1b82b92af1be73ea29686b8200a0caf4d0
- Resolution set to fixed
- Status changed from positive_review to closed
Note: See
TracTickets for help on using
tickets.
Looks good to me.