hplgit/fem-book

Equation 5.35 dimensionaly incorrect

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thank for sharing this nice book on the web.

In section 5.5.5 Convenient formulas for P1 elements

!bt
\begin{equation}
\basphi_I (x,y) = \half\Delta \left( \alpha_I + \beta_Ix
+ \gamma_Iy\right),
label{fem:approx:fe:2D:phi:I}
\end{equation}
!et

The formula for $\phi_I$ is dimensionaly incorrect. $\phi_I$ should have no unit and the right hand side has $[m^2]$. It should be $\frac{1}{2 \Delta}$ in the prefactor and not $\frac{1}{2 } \Delta$

grafik