Local Jacobian matrix

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1

Hello,

is there a way to retrieve the element jacobian matrix G of the transformation from local (u,v,w) to global (x,y,z) coordinates in a Pythonic way?

I would like to compute the forces via the direct virtual work approach on element level. Therefore, I need the determinant of the jacobian and the derivative of the jacobian along the direction s.

I would be glad about any hint!

2

Hi creativeworker,

the specialcf.JacobianMatrix(dim) gives the Jacobian matrix of the transformation to the physical elements.

Best
Michael

3

Thank you for this hint!
I wonder, how I could manage to generate a CoefficientFunction which represents the derivative of the Jacobian along the direction s?
I think of finite differences and a mesh that is deformed conformly. But I could not manage to find a way how to work it out.

4

A neat solution would be to make use of the Differentiation of the CoefficientFunction (here the JacobianMatrix) with included parameter s. But I can’t see how the virtual mesh deformation could be realized using the parameter.