[?] Why does this ParametricPlot3D show no output?

Questions
1

Hello,

I am trying around with some code I found on the web:

ParametricPlot3D[{r Sin[theta], r Cos[theta], 
  0.01 Sin[7 (4 r - theta)] - 0.1/r, EdgeForm[]}, {r, 0.1, 
  Sqrt[2]}, {theta, 0, 2 Pi}, 
 PlotRange -> {{-1, 1}, {-1, 1}, {-1, 0}}, PlotPoints -> {50, 360}, 
 Boxed -> False, Axes -> None]

But the output is ‘nothing’/empty when I evaluate it. Same if I try to export as a .jpg…but why? Any ideas what is wrong?

Many thanks already.

2

try without EdgeForm[]

ParametricPlot3D[{r Sin[theta],r Cos[theta],0.01 Sin[7 (4 r-theta)]-0.1/r},
{r,0.1,Sqrt[2]},
{theta,0,2 Pi},
PlotRange->{{-1,1},{-1,1},{-1,0}},
PlotPoints->{50,360},
Boxed->False,Axes->None]

Untitled3.jpg
Untitled3.jpg479×250 33.4 KB

3

Ok,that works, and why does EdgeForm[] not work this way? Isn’t it ‘responsible’ for the black grid?
How could I remove it, the black grid?

Edit: Got it, Mesh->None

4

You can suppress the grid with Mesh -> None. Where did you get the idea of adding a fourth argument to the function? I wonder if it was a pre-version-6 trick.

5

You’re right, its a code from Paul Nylander, probably from 1997.

There are also many other older sourcecodes which seems to work in a bit different way today, using RasterArray for example…but verry interesting anyway for newbies like me.