How to use curl for 2D-vector field correctly?

Hi everyone,

I've some data from a simulation like (x,y,u,v) which u corresponds to velocity in x-direction and v in y-direction. In order to compute the curl of vector V(u,v) i did it like so:

x = data(:,1);
y = data(:,2);
u = data(:,3);
v = data(:,4);
V = [u v];
R = [x y];
curl = curl(V,R);

Now i wanna to see if my code is correct or is there any mistake?

Many thanks!

[Andreas Passos]

I have the exact same question,

'how to calculate the curl of a trajectory'

if you found the answer please let me know

Answer 1

[Jess Lovering]

I think you might have to make those inputs into matrix format first with meshgrid. Then you can pass those directly into curl.

x = data(:,1);

y = data(:,2);

u = data(:,3);

v = data(:,4);

[X,Y] = meshgrid(x,y);

[U,V] = meshgrid(u,v);

curl = curl(X,Y,U,V);

[Nima]

If I use meshgrid, then I will receive 0 and NAN as results of curl!

[Jess Lovering]

Sorry - you are right. I am not sure because the help says it needs to be a matrix "as if produced by meshgrid."