Opened 4 years ago
Closed 4 years ago
#19472 closed enhancement (fixed)
GLPK backend: More basis status and tableau data functions
Reported by: | mkoeppe | Owned by: | |
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Priority: | major | Milestone: | sage-6.10 |
Component: | numerical | Keywords: | lp |
Cc: | zwang, dimpase, ncohen, vdelecroix, yzh | Merged in: | |
Authors: | Aedi Wang | Reviewers: | Dima Pasechnik |
Report Upstream: | N/A | Work issues: | |
Branch: | 37e90e8 (Commits) | Commit: | 37e90e85d2e635f929abec54bdc62b17b93184b0 |
Dependencies: | Stopgaps: |
Description (last modified by )
Change History (9)
comment:1 Changed 4 years ago by
- Type changed from PLEASE CHANGE to enhancement
comment:2 Changed 4 years ago by
- Description modified (diff)
comment:3 Changed 4 years ago by
- Branch set to u/zwang/GLPK_backend_More_basis_status_and_tableau_data_functions
comment:4 Changed 4 years ago by
- Cc dimpase ncohen vdelecroix yzh added
- Commit set to 37e90e85d2e635f929abec54bdc62b17b93184b0
- Status changed from new to needs_review
comment:5 follow-up: ↓ 6 Changed 4 years ago by
Is it possible to add a short explanation of (and a reference) what "warming up the basis" means?
And another question - will there be any frontend functions available to take advantage of this stuff, or it's got to be backend-specific?
comment:6 in reply to: ↑ 5 Changed 4 years ago by
Replying to dimpase:
Is it possible to add a short explanation of (and a reference) what "warming up the basis" means?
The GLPK manual offers this explanation: "This operation includes computing factorization of the basis matrix (if it does not exist), com- puting primal and dual components of basic solution, and determining the solution status." I'm not sure if it's worth adding it.
And another question - will there be any frontend functions available to take advantage of this stuff, or it's got to be backend-specific?
Our current plan is to expose these functions only through a simplified interface that we call "LPBackendDictionary" (#18804), which offers a naive "textbook-style" view on the simplex solvers.
A full-featured frontend interface would be rather tricky. OSI tried that and I'm not sure it really succeeded.
comment:8 Changed 4 years ago by
- Reviewers set to Dima Pasechnik
comment:9 Changed 4 years ago by
- Branch changed from u/zwang/GLPK_backend_More_basis_status_and_tableau_data_functions to 37e90e85d2e635f929abec54bdc62b17b93184b0
- Resolution set to fixed
- Status changed from positive_review to closed
New commits:
More basis status and tableau data functions