# Re: [deal.II] FE w/ Gauss Point DoFs

```Dear Jonathan,

Is FE_DGQArbitraryNodes
<http://dealii.org/8.5.1/doxygen/deal.II/classFE__DGQArbitraryNodes.html>
perhaps what youâ€™re looking for? From the documentation:```
```
> The primary purpose of this class is to provide an element for which the mass
> matrix can be made diagonal by choosing basis functions that are not either
> zero or one at the vertices of the cell, but instead are zero or one at a
> given set of quadrature points.

J-P

> On 07 Mar 2018, at 18:09, Jonathan Russ <jr3...@columbia.edu> wrote:
>
> Bruno -
>
> Thank you for your help. I see what you are saying. In this way I would need
> to make sure I have the same number of gauss points as nodes in the finite
> element since deal.II will assume that the stress degrees of freedom are
> associated with the nodes. For now I don't believe this is too strict of a
> limitation for me since I will likely choose the quadrature rule such that
> the number of quadrature points is equal to the number of nodes anyways.
> Perhaps there is a better way to handle this situation but I will try this
> for now. Thanks again!
>
> Jonathan
>
> On Wednesday, March 7, 2018 at 11:04:33 AM UTC-5, Bruno Turcksin wrote:
> Jonathan,
>
> 2018-03-07 10:43 GMT-05:00 Jonathan Russ <jr3...@columbia.edu <javascript:>>:
>
> Thank you for your fast reply. I'm sorry I'm not doing a great job of
> explaining this. Here is an example from elasticity that illustrates what I
> would like:
> In this case there are displacement degrees of freedom at the nodes but the
> stress is a quantity typically derived from the displacements. However, one
> could make the stress an independent degree of freedom at the gauss points.
>
> So, in the element there would be displacement degrees of freedom at the
> nodes and stress degrees of freedom at the gauss points. Does this make sense?
> I don't think there is a way to do that in deal unless you can split your
> finite elements, i.e., you have one FE_Q for the displacement and another
> FE_Q for the stress. Then, you can use FESystem. But do I understand
> correctly that the stress is not describe by any finite element but you would
> like to use dof_handler to help you manage some data. In that case, I think
> that using a FESystem should work, you just will never call FEValues for the
> stress since you don't care about the associated finite element but the
> dof_handler will associate a degree of freedom to each quadrature point.
>
> Best,
>
> Bruno
>
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