Hi Eddy,
If you are taking derivatives w.r.t a parameter, a finer mesh may give you very wrong results unless you vary the parameter slowly too. That is, the finer your mesh the smaller the variation of your parameter should be. So take a very small dL say for the variation of length.
I have...
Hi Eddy,
I think this is some how theoretical.
Usually the values of your independent variable are computed over the nodes during processsing and you get the derivatives by post processing (like strain is obtained as a derivative of displacements). The unknowns are continuous over elements. So...
