Why is my surface not fitting the data points smoothly?

Hi,

I have a set of 125 (x,y,z) data points that are supposed to represent smooth planes. I am trying to calculate the curvature on these planes but the surfaces are not fitting the data points smoothly (please see below). I don't know why this is happening and if anyone could provide advice that would be much fantastic.

[Star Strider]

The gap could be NaN values. Do you have any in your data?

[Nicholas]

No I don't have any NaNs in the data set - is it possible that there aren't enough points?

[Star Strider]

If you have 125 data triplets, and none of them are NaN, you should have enough points to define your surface. I would use scatter3 or stem3 (that I prefer because it tells me where the x and y coordinates for a particular z are located) to see what your data look like with it. It could give you some insight into the problem.

Answer 1

[Alessandro Masullo]

You can try to plot your surface with trisurf:

     [x,y]=meshgrid(1:15,1:15);
     tri = delaunay(x,y);
     z = peaks(15);
     trisurf(tri,x,y,z)

Can your problem be related to the points order?

There's also a Matlab bug related with the plot of surfaces. Try to execute opengl software, close all your windows and try again.

[Nicholas]

I think the points order is probably influencing this as if I change the shape of the arrays, a different surface appears. I have no clue as to why reshaping the arrays would be doing this though