Finite element discretization spaces
Full de Rham complex
The picture below taken from here , displays from left to right:

H1−conforming (continuous)
H(curl)−conforming (continuous tangential component)
H(div)−conforming (continuous normal component)
L2−conforming (discontinuous)
The picture also displays from top to bottom the increasing discretization order for the full de Rham complex.

Quesiton
Integration points
Is the right-hand side of the picture above, i.e. L2−conforming (discontinuous), actually showing the equivalent of the integration points discussed on CCX documentation ?

In mfem you can choose different integration schemes or even code a custom one.
I think the standard in mfem is the gauss legendre.

You would need to compare the integration point coordinates from mfem with the calculix source code to see if they are equivalent.

https://docs.mfem.org/html/intrules_8cpp_source.html

```
!
! contains Gauss point information
!
! gauss1d1: lin, 1-point integration (1 integration point)
! gauss1d2: lin, 2-point integration (2 integration points)
! gauss1d3: lin, 3-point integration (3 integration points)
! gauss2d1: quad, 1-point integration (1 integration point)
! gauss2d2: quad, 2-point integration (4 integration points)
! gauss2d3: quad, 3-point integration (9 integration points)
! gauss2d4: tri, 1 integration point
! gauss2d5: tri, 3 integration points
! gauss2d6: tri, 7 integration points
! gauss3d1: hex, 1-point integration (1 integration point)
! gauss3d2: hex, 2-point integration (8 integration points)
! gauss3d3: hex, 3-point integration (27 integration points)
! gauss3d4: tet, 1 integration point
! gauss3d5: tet, 4 integration points
! gauss3d6: tet, 15 integration points
! gauss3d7: wedge, 2 integration points
! gauss3d8: wedge, 9 integration points
```

This file has been truncated. show original

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