Define Paraboloid of Revolution

Hi guys,

I want to define a surface through GH which essentially is a Paraboloid of Revolution.

The equation is: b*z = x^2 + y^2

b is a constant I have.

How do I do this?

(I know how to create it by defining a parabola and then revolve it around an axis, but I wonder if there is a way to define directly the whole surface since I have the value b only for the equation of the paraboloid and not for its parabola)

Thanks!

Replies to This Discussion

Permalink Reply by Pieter Segeren on September 30, 2014 at 2:35pm

Hi marinako,
is this what you mean:
or maybe trim it so it's a "revolution":

Attachments:

paraboloid from pointgrid_Trimmed_PSG.gh, 23 KB

Permalink Reply by marinako on September 30, 2014 at 3:03pm

works :)

Permalink Reply by nikos tzar on September 30, 2014 at 3:00pm

Hello marinako, Pieter,

Only thing to add to Pieter's definition is you can define x and y to be inside a circle so that you have an untrimed surface:

Attachments:

paraboloid.gh, 11 KB

Permalink Reply by marinako on September 30, 2014 at 3:03pm

Thanks guys

Great!

Permalink Reply by Pieter Segeren on September 30, 2014 at 3:20pm

Nice one Nikos, thanks.

Permalink Reply by alparslan zafar on February 7, 2015 at 10:31am

I tried this tutorial in order to get sphere instead of paraboloid. But ı can't get a surface.I got only dots. Is there any body to say where is my error. Thanks everybody.

Permalink Reply by alparslan zafar on February 7, 2015 at 11:47am

here is graskopper screen shoot

Attachments:

Yeni Bit Eşlem Resmi.bmp, 1.3 MB

Permalink Reply by Pieter Segeren on February 7, 2015 at 1:35pm

Besides the fact that the SurfaceFromPoints should get a flat list of points (I flattened the DivideSurface P(Points) output back then to ensure that), I think your Expression always fails (results in all NaN's (NotANumber)) because of the negative values between the Sqrt() brackets. Hum, I hope that was understandable/english enough to pass as an answer ;)

Permalink Reply by alparslan zafar on February 13, 2015 at 5:38pm

thank you very much.

Permalink Reply by alparslan zafar on February 13, 2015 at 5:58pm

To be able to draw same sphere with the following parameter istedad of using an implicit equation what changes should I make?

x=1-s^2-t^2/1+s^2+t^2

y=2*s/1+s^2+t^2

z=2*t/1+s^2+t^2

ı spare two day to draw it but ı can'T.

could ı ask you also,if it is possible to draw it using single function by vector notation {x,y,z}

Thank you very much a gain.

Permalink Reply by alparslan zafar on February 7, 2015 at 11:46am

here is grashoper screen