Derivative of the surface function considering the z-axis
\[\begin{split}\frac{\partial\Phi}{\partial z}(r,\phi,z)=
\begin{bmatrix}0\\0\\1\end{bmatrix}\end{split}\]
with radius \(r\), polar angle \(\phi\) and cylinder length
\(z\).
Parameters: |
- r : float
Radius
- phi : float
Polar angle
- z : float
Distance ins z-axis
|
Returns: |
- pos : list
Cartesian coordinates for given polar coordinates
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