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Computing second derivative with deformed Geometry

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Hello,

I'm trying to figure out how set the second derivative of a boundary as a variable, but the mesh is changing so it has to be re-calculated every time step. Is there some way to have the second derivative along the boundary be recalculated every time the mesh is updated?

In addition, I'm also having trouble even plotting the second derivative, I can plot (in axis-symmetrical) z(r), a Gaussian, but when I try to plot 'd(z,r)' it gives me a constant 0, which I know isn't right.

-Ben
EDIT:
I was able to plot a first derivative with dtang(z,r), but if I did dtang(dtang(z,r),r) then I get a constant 0 value again.


0 Replies Last Post 13 juin 2016, 14:45 UTC−4
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Hello Ben Cutler

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