Hi. I’m currently trying to calculate the vorticity and the q-criterion using the “Gradient of Unstructured Data set” filter, with the velocity data set of a Cartesian grid, formatted as follows.

density u v w

value value value value

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I use the calculator filter and use

u*iHat+v*jHat+w*kHat

to construct my velocity factor, to which I apply the “Gradient of Unstructured Data set” filter.

From my online research, it should show me the “Compute vorticity” and “Compute QCriterion” options, but I do not see those options pop up when I select the filter. I’d appreciate it if you could let me know why I don’t see those options.

Thanks for you time.