Table 1 Algorithm 5.1, Example 1

Mesh

$\mathbf{\parallel }\mathit{u}\mathbf{-}{\mathit{u}}_{\mathit{h}}\mathbf{\parallel }$

$\mathbf{\parallel }\mathit{y}\mathbf{-}{\mathit{y}}_{\mathit{h}}\mathbf{\parallel }$

$\mathbf{\parallel }\mathit{p}\mathbf{-}{\mathit{p}}_{\mathit{h}}\mathbf{\parallel }$