an encyclopedia of finite element definitions
Degree 2 Lagrange on a interval
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- \(R\) is the reference interval. The following numbering of the subentities of the reference is used:
- \(\mathcal{V}\) is spanned by: \(1\), \(x\), \(x^{2}\)
- \(\mathcal{L}=\{l_0,...,l_{2}\}\)
- Functionals and basis functions:
\(\displaystyle l_{0}:v\mapsto v(0)\)
\(\displaystyle \phi_{0} = 1 - x\)
This DOF is associated with vertex 0 of the reference element.
\(\displaystyle \phi_{0} = 1 - x\)
This DOF is associated with vertex 0 of the reference element.
\(\displaystyle l_{1}:v\mapsto v(1)\)
\(\displaystyle \phi_{1} = x\)
This DOF is associated with vertex 1 of the reference element.
\(\displaystyle \phi_{1} = x\)
This DOF is associated with vertex 1 of the reference element.
\(\displaystyle l_{2}:\mathbf{v}\mapsto\displaystyle\int_{R}(\sqrt{3} \cdot \left(60 s_{0}^{2} - 60 s_{0} + 10\right))v\)
where \(R\) is the reference element;
and \(s_{0}\) is a parametrisation of \(R\).
\(\displaystyle \phi_{2} = \sqrt{3} x \left(x - 1\right)\)
This DOF is associated with edge 0 of the reference element.
where \(R\) is the reference element;
and \(s_{0}\) is a parametrisation of \(R\).
\(\displaystyle \phi_{2} = \sqrt{3} x \left(x - 1\right)\)
This DOF is associated with edge 0 of the reference element.