Problems with MathScript node

[Quizma]

Hi!

I have following Matlab-code that works fine with Matlab, but when I try to use it with Mathscript node, it won't work properly. The inputs r, th and Z are 2D-arrays. The problem seems to be that "hold on" function won't work and when I try to display the contour within a polar axes, I get error: "-90052 occurred at Error in function polar at line 9.  You specified an invalid number of output parameters for this function". I'm just a novice at LabView and I appreciate if You can help me a bit.

[X,Y] = pol2cart(th*3.14159/180,r);
[XI,YI] = meshgrid(-1:0.01:1,-1:.01:1);
ZI = griddata(X,Y,Z,XI,YI,'cubic');
surf(XI,YI,ZI)
hold on
surf(X,Y,zeros(size(X)))
hold off
axis equal
h = polar([0 2*pi], [0 1]);
delete(h)
hold on
contourf(XI,YI,ZI,20)

Sincerely

Quizma

[altenbach]

What is your LabVIEW version? Can you attach a small VI containing typical data?

[Quizma]

LabView verison is 8.5.1

[Quizma]

And with correct data...:

[GrantM]

Hello Quizma,

Unfortunately, your script exposes a few weaknesses in MathScript.  Currently, hold on doesn't work for 3D graphs (such as surf).  There is currently a bug report for this (id: 53392).  Also, the MathScript polar command does not produce any output.  This is why you receive the error you mention.  Remove the "h =" from line 9 of your script and then you can delete line 10.  In my testing with 8.5.1, there seems to be a bug in the griddata function when using the 'cubic' option.  It produces an array of zeros.  Try using the 'v4' option instead.  I have also tried your VI in LabVIEW 8.6.  It seems to hang with both the 'cubic' and 'linear' option, but works fine with the 'v4' option.  I have filed a bug report for this issue as well (id: 124923).

Grant M.
Staff Software Engineer | LabVIEW Math & Signal Processing | National Instruments