The surface I want to plot is $z^2 + r^2 = 25\, \theta$.
Please tell me how to do it in Mathematica.
Brandon: You could modify the example given in: How do I make a 3DPlot using cylindrical coordinates? as follows:
cylinderPlot3D[f_, {rMin_, rMax_}, {\[Theta]Min_, \[Theta]Max_},opts___] :=ParametricPlot3D[{r Cos[\[Theta]], r Sin[\[Theta]],f[r, \[Theta]]}, {r, rMin, rMax}, {\[Theta], \[Theta]Min, \[Theta]Max}, opts]
g[r_, \[Theta]_] := Sqrt[25 \[Theta] - r^2];
cylinderPlot3D[g, {0, 1}, {0, 2 Pi}, Mesh -> None, Boxed -> True]
ContourPlot3D
? $\endgroup$TransformedField
. You can then applyContourPlot3D[Evaluate@TransformedField[..],...]
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