Sparse data interpolation [surface fit]

[cRIO+FPGA Apps]

I've seen this problem before in the forums however, I'm still hitting a wall!

I have a set of sparse x, y, z data (see attached). I need to interpolate and populate a table with the interpolated valuesand finally get the surface plot. This topic was discussed in , http://forums.ni.com/ni/board/message?board.id=170&message.id=376161&query.id=73383#M376161 , but the VIs provided (also attached) would not work, could someone please tell me why. Other ways to attack this problem are also welcome.

Thanks!

[Will_S.]

Hi cRIO,

Is the issue you receive an error or unexpected behavior from running these VIs, or that they are not providing you with a desired interpolation and surface plot?

[Batman1]

Did you ever solve this problem?

We are trying to do a 3d surface fit of a grid of sparse points and there is no built in vi in Labview that does this in one step.

Any solution?

Thanks. 

[GregSands]

What have you tried already?  There is a Mathscript command called intrp2d_uneven (used to be called griddata) which does interpolation of unevenly spaced grid points.  Have a look here too.

If this doesn't work for you, I've found Kriging interpolation to give good results for many cases.