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sddsinterp returns error when interpolating on the grid

Posted: 13 Sep 2011, 10:10
by wguo
Hi Michael,

When I use sddsinterp and set -order=4, the program returns an error message: zero denominator in LagrangeInterp when
the interpolation happens to be on the grid. What should I do?

Many thanks,

Weiming

Re: sddsinterp returns error when interpolating on the grid

Posted: 13 Sep 2011, 10:23
by michael_borland
Weiming,

Can you send me (or post) the data and the full command used?

--Michael

Re: sddsinterp returns error when interpolating on the grid

Posted: 13 Sep 2011, 15:04
by wguo
Hi Michael,

The error circumstance is not what I thought.
Use the attched file: test0.sdds and the following command:

sddsinterp test0.sdds test1.sdds -col=x,Byn10 -atValues=0.00013942073576 -order=4

The reason it quits is because there are many repeated values as following:

x: -2,-1,0,0,0,0,0,0,1,2
Byn10: 4002,4001,4000,4000,4000,4000,4000,4000,3999,3998

Can I claim it as a bug, or, should I fix the data myself?

Many thanks,

Weiming

Re: sddsinterp returns error when interpolating on the grid

Posted: 13 Sep 2011, 15:37
by michael_borland
Weiming,

The program doesn't give a clear enough error message, so we'll fix it. Thanks for reporting the problem.

By the way, you can easily fix the problem with
% sddssort test0.sdds -column=x -unique

--Michael

Re: sddsinterp returns error when interpolating on the grid

Posted: 13 Sep 2011, 15:39
by wguo
Hi Michael,

Thanks for showing me the trick!

Weiming