how to plot a cone using 3D control

[richjoh]

I just can't seem to get the geometry right on the 3D surface plot. I am attempting to plot a cone shape use an x-component and y-component in a 360 degree circle at every z elevation (height). I either wind up with a plane (2D)surface or some obscure shape. What am I missing here? I have attached a sample vi.

I LV examples don't help me for this case.

[richjoh]

Whoops the above attachment was not the right one. It is an example from another post.

 The VI I want to attached is now correct.

[Evan]

You are close.  The parametric equation for z is z(theta,r)=r

So you just need a 2D array of r.  Take a look at the attached.

[richjoh]

Oh that's news to me. I forgot to mention I am using LV 7.1 can you save the VI as a 7.1.

Thanks again.

[Evan]

The VI was in 7.1 but here is another copy.  All I did was remove the bottom loop.  And instead in the top 2 loops take the i from the outer loop into the inner loop and then right out to the z input, allow autoindexing on both loops.  Basically a 2D array is created of the r you are using.

To find the equation I just googled parametric equation cone and found this pdf   So thanks University of Minnesota

http://www.math.umn.edu/~edman/math2374/solutions9.pdf

[richjoh]

Evan,

Thanks, I was able to open your original file, I had to replace the Pic Control to get it to run. I'm not getting a cone shape are you? see the attached pic

Thanks for your help

[Evan]

Here is what I get.

[richjoh]

OK I got it. My radius was set to zero ;^). It now looks like yours when there's a radius.

Thx Much.