Error when using streamline() function

Hello,

I would like to produce a streamline plot of some data I have generated with another program. The data are of u-velocities(stream wise) and v-velocities (span wise) generated by a navier stokes solver on a 2-d mesh using Finite Volume Method.

I can get the streamline function to work with data that was generated on a square mesh with uniform cell spacing. However, when I try to use the streamline function with data that was generated on a non-square mesh with non-uniform spacing I get this error:

>> streamline(coordsx,coordsy,u(:,:,11),v(:,:,11),0.5,0.5) Error using griddedInterpolant Interpolation requires at least two sample points in each dimension.

Error in interp1 (line 191) F = griddedInterpolant(X,V,method);

Error in stream2 (line 63) sxi=interp1(xx(:),1:szu(2),sx(k));

Error in streamline (line 63) verts = stream2(x,y,u,v,sx,sy,options);

Here is what the actual data looks like on the non-square mesh using surf plot

I don't understand what this error means because when I use the function on a square, uniform mesh, it works fine.

Please note that the size of coordsx, coordsy, u(:,:,11), v(:,:,11) are 201x51 (i.e. the size of the mesh shown in the pictures).

Can anyone help me figure out why streamline is producing this error when I use perfectly good data?

Thank you.

Answer 1

[Kasper van der Vaart]

I also stumbled upon this error. It turns out that going from: streamline(x,y,u,v,startx,starty)

to

streamline(x',y',u',v',startx,starty)

did the trick for me. Interestingly enough quiver does not seem to have a problem with this.

[Andrew Winter]

Thank you so much for coming back to post your solution! I was having the same problem and this saved me so much trouble. Thanks again!

Best regards, Andrew

Answer 2

[Kalpit Bakal]

I am still facing the same problem even after doing what Kasper suggested. Can somebody help me with this.

Answer 3

[Mohan Mond]

Thx!!

This issue exists still in R2019b for streamslices.