Ticket #13519 (closed defect: fixed)
Spline is not recomputed when interpolation points change
| Reported by: | jvkersch | Owned by: | jason, jkantor |
|---|---|---|---|
| Priority: | major | Milestone: | sage-5.5 |
| Component: | numerical | Keywords: | spline, gsl |
| Cc: | kcrisman | Work issues: | |
| Report Upstream: | N/A | Reviewers: | Travis Scrimshaw |
| Authors: | Joris Vankerschaver | Merged in: | sage-5.5.beta0 |
| Dependencies: | Stopgaps: |
Description
The sage.gsl.interpolation.Spline class does not recompute the spline when the interpolation points are changed:
sage: S = spline([(1,1), (2,3), (4,5), (5, 4)]); S [(1, 1), (2, 3), (4, 5), (5, 4)] sage: S(4.1) 4.953437500000001 sage: del S[1]; S [(1, 1), (4, 5), (5, 4)] sage: S(4.1) 4.953437500000001 sage: S.append((4, 100)); S [(1, 1), (4, 5), (5, 4), (4, 100)] sage: S(4.1) 4.953437500000001
Attachments
-
13519-gsl-spline.patch
(4.3 KB) -
added by jvkersch 8 months ago.
Change History
comment:1 Changed 8 months ago by jvkersch
- Status changed from new to needs_review
- Authors set to Joris Vankerschaver
comment:3 Changed 8 months ago by tscrim
- Status changed from needs_review to needs_work
I get the following errors
File "/home/travis/sage-5.4.beta1/devel/sage-reviews/sage/gsl/interpolation.pyx", line 30:
sage: S(1.5)
Expected:
2.507575757575758
Got:
2.5075757575757573
**********************************************************************
File "/home/travis/sage-5.4.beta1/devel/sage-reviews/sage/gsl/interpolation.pyx", line 44:
sage: S(1.5)
Expected:
2.507575757575758
Got:
2.5075757575757573
**********************************************************************
which is just a rounding issue. The rest of the documentation has 16 numbers after the decimal.
Also I think you should use single backticks to get math mode and double backticks for inline code in the documentation, and use the automatic trac link :trac:'13519' where the single quotes are backticks (since I don't know how to get the escape to work here) instead of #13519 on line 131. The functionality looks good otherwise.
comment:4 Changed 8 months ago by jvkersch
- Status changed from needs_work to needs_review
Hey Travis, nice catch. I've uploaded a new version of the patch, where I've made the following changes:
- I didn't have the rounding issue on my machine, but to make things more robust I've replaced the last few digits of each repeating decimal expansion by an ellipsis.
- I've incorporated the automatic links to trac and the formatting for math mode and inline code. I've also made this change elsewhere in the file, so the resulting patch is a little larger than the previous one, but all the new changes just concern formatting.
Let me know if you have any further suggestions for changes.
comment:5 Changed 8 months ago by tscrim
- Status changed from needs_review to positive_review
- Reviewers set to Travis Scrimshaw
Looks good to me.
The patch corrects this behavior and adds some examples to the class docstring.