Bug 57234 - Incorrect b-spline smoothing
Summary: Incorrect b-spline smoothing
Status: RESOLVED DUPLICATE of bug 47787
Alias: None
Product: LibreOffice
Classification: Unclassified
Component: Chart (show other bugs)
Version:
(earliest affected)
3.6.3.2 release
Hardware: Other All
: medium normal
Assignee: Not Assigned
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Reported: 2012-11-17 21:04 UTC by souradova
Modified: 2013-02-14 16:40 UTC (History)
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Description souradova 2012-11-17 21:04:43 UTC 
Smoothing for XY graph is incorrect when b-spline is selected. It interpolates the data points with a polynome that goes through the points exactly which should generally not be the case for b-spline. See 

http://en.wikipedia.org/wiki/B-spline

for more info about the correct b-spline smoothing. Now it looks, on first look, more like hermitan polynome interpolation instead of B-spline smoothing.
Comment 1 Markus Mohrhard 2013-02-14 16:40:02 UTC 
The B-Spline algorithm is specified by ODF 1.2 so we have to implement the algorithm mentioned there. However there is still an issue in the implementation and I was yet unable to spend enough time in fixing it.

*** This bug has been marked as a duplicate of bug 47787 ***