an encyclopedia of finite element definitions

# P1-iso-P2

 Alternative names P2-iso-P1, iso-P2 P1 Orders $$k=1$$ Reference elements interval, triangle, quadrilateral DOFs On each vertex: point evaluations On each edge: point evaluations On each face: point evaluations Number of DOFs interval: $$3$$triangle: $$6$$quadrilateral: $$9$$ Number of DOFs on subentities vertices: $$1$$edges: $$1$$faces: $$0$$ (triangle), $$1$$ (quadrilateral) Mapping identity continuity Function values are continuous. Categories Scalar-valued elements, Macro elements

## Implementations

 Basix basix.ElementFamily.iso↓ Show Basix examples ↓ This implementation is correct for all the examples below. Basix.UFL basix.ElementFamily.iso↓ Show Basix.UFL examples ↓ This implementation is correct for all the examples below. Symfem "P1-iso-P2"↓ Show Symfem examples ↓ This implementation is used to compute the examples below and verify other implementations.

## Examples

 intervalorder 1 (click to view basis functions) triangleorder 1 (click to view basis functions) quadrilateralorder 1 (click to view basis functions)

## References

• Bercovier, Michel and Pironneau, Olivier. Error estimates for finite element method solution of the Stokes problem in the primitive variables, Numerische Mathematik 33, 211–224, 1979. [DOI: 10.1007/BF01399555] [BibTeX]

## DefElement stats

 Element added 06 July 2022 Element last updated 16 September 2023