How to plot contour without interpolation on a nonuniform grid?

Hi. The data I wish to plot (or post-process) is CFD data (vorticity, pressure, etc) from fluent. The grid is non-uniform, as the image shows, with a finner mesh near the square cavity.

Obviously I can use either 'scatteredinterpolate' or 'griddata' with a regenerated grid, like:

xmin = min(xx); xmax = max(xx);
ymin = min(yy); ymax = max(yy);
 
[x,y]=meshgrid(xmin:1e-3:xmax,ymin:1e-3:ymax);
vq = griddata(xx,yy,Vort,x,y);

However, I think this interpolation compromises the integrity of my data, since many details may be lost. I thought of using 'reshape', but since the grid is not non-uniform, this becomes very difficult. I attempted creating a uniform grid with lots of 'NaN' indicating no data. But plotting it just gave me no data at all. I have attached my code. The data is too big for attachment ~300Mb. Can someone please help? Much appreciated.

Answer 1

[Star Strider]

Have you experimented to see how contour (or contourf) works with your data? Did the function throw an error?

If not, just let contour (or contourf) loose on your data and see what the result is.

The function is reasonably robust.

Example:

x = randn(10);
y = randn(10);
z = randn(10);

figure
contourf(x, y, z, 'LineStyle','none')

[Abdallah Ghazal]

Hi, I have a similar problem. I want to plot a contour with the original data for a nonuniform grid. The output file that I want to draw gives X, Y and Z as vectors, therefore, the contourf will not work. Any suggestions?