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cspline routine

Posted: Sat Feb 23, 2013 10:25 am
by BruceWilliams2010
Need someone to develop a macro that can do a cspline output with the results in the Calc spreadsheet and do it with the same accuracy as the smooth function when graphing XY plots. This is for Open Offcie 3.4.?
Have tried some of the VBA codes listed on this site but none produce results even close to accurate, some are actually reversed in the results or have discontinuities or results way out of range. If you are interested I will send you a spread sheet with 3 sheets. Each one with different values and the associated graph for test purposes.

Re: cspline routine

Posted: Sat Feb 23, 2013 5:44 pm
by acknak
Could I suggest that you attach your sample document to your discussion thread: http://forum.openoffice.org/en/forum/vi ... 65#p264865

And, perhaps, a comment as to why this particular function is important for your analysis? (I'm just curious, but it might help to get someone interested in cobbling something up).

Maybe you want to wait until someone steps up before putting the time in, but a link to some background on the function and some sample data and correct output would all be necessary at some point; again, it could help get someone interested sooner rather than later.

I'd also suggest that any follow-up posts not directly involving paid support should go on the other thread. You can mention your offer there as well and paste a link to this thread, if you like.

Re: cspline routine

Posted: Sun Feb 24, 2013 8:59 pm
by BruceWilliams2010
Here is an OO calc sheet that I tested the routines with. If your routine can match the graphs output then I will be willing to pay for it.

I wish to use this routine to check for frequency shifts as light passes through different detectors. In other words, how reproducible are they?

Thank you for your time
Bruce Williams

Re: cspline routine

Posted: Sun Feb 24, 2013 10:14 pm
by Villeroy

Re: cspline routine

Posted: Mon Feb 25, 2013 5:28 am
by BruceWilliams2010
cspline ver 0.5 has some major problems with OOo 3.4.1 in Windows 7 and a google search only shows Excell spread sheet add ons. No real help sorry to say.

Thank you for your help though.

Bruce Williams

Re: cspline routine

Posted: Wed Feb 27, 2013 1:46 am
by Villeroy
http://forum.openoffice.org/en/forum/vi ... =45&t=4574

there are 19 more search results when you type cubic spline into this forum's search box.

Re: cspline routine

Posted: Tue Feb 10, 2015 7:57 am
by MrProgrammer
BruceWilliams2010 wrote:Here is an OO calc sheet that I tested the routines with. If your routine can match the graphs output then I will be willing to pay for it.
Spline Interpolation describes how to interpolate data points using cubic splines. It's not hard to implement in Calc with formulas. I've attached an example of the calculations with your data. You can see that the charts made with the interpolated points match the charts created by requesting Smooth Lines → Properties → Cubic Spline.

If this method satisfies your needs, and you were sincere about paying for the support, simply make a donation, say US$ 100, to the Open Office project. I won't receive any of that money, but it will go to a good cause.

If this answered your question please go to your first post use the Edit button and add [Solved] to the start of the title. You can select the green checkmark icon at the same time.

Re: cspline routine

Posted: Wed Feb 18, 2015 12:49 am
by haptsurk
Thank you for taking the time to produce this spread sheet. I just got time to go through my emails today. I will test it against some of my manual results and if it gives me good answers I will be more than happy to donate the $100.

Thank you for your time

Bruce Williams