Hi,
I’m a little new to NGSolve and was looking for an operator for a simple partial derivative to solve a problem with a Bilinear form that might look like this:

I found that coefficient functions have a partial derivative method called diff(), I was hoping there would be somthing similar for test and trial functions that might look something like this:

a = BilinearForm(fes)
a+=(diff(u,x)*diff(v,x))*dx

Does such an function exist in NGSolve (obviously the above doesn’t work)? Sorry if I simply haven’t read the documentation well enough

Thanks for your post. What if u and v are not scalars? In other words, if u is a vector, can we get one component of u first, then take the gradient, then pick the i th component? Thanks in advance!