how can i get.................

[dipt]

hi
how can i get the co-ordinates of each node of a octagon circle around a central node having co-ordinate (0,0,0)
plz help me

 

[harsha_jois]

If I'm getting this right you have a circle circumscribing an octagon with centre at the origin.
But, as both the objects described are planes, the coordinates need only be (0,0).
Calculate the angle subtended by each pair of radii marking the vertices of the octagon 360/8
then use the arcsine function to get the length of the segment ie the edge.
use distance formula backwards.
Hope this is clear

 

[doraemon]

Hello!

I will assume that:
Your octagon is in a circle of radius r.
The center of this circle is (0,0). Is it right?

Now let's assume that you have 4 "nodes" on the axes. Therefore, these 4
nodes will be (r, 0), (0, r), (-r, 0), (0, -r)
As for the 4 other nodes, they will be:
(r*root2, r*root2), (-r*root2, r*root2), (-r*root2, -r*root2), (r*root2, -r*root2)

where root2 = half of root of 2 or 0.707...

And more generally, if you have an octagon rotated by angle phi, the "nodes"
will be:
(r*cos(phi+i*pi/4), r*sin(phi+i*pi/4), i being in {0, 1, 2, 3, 4, 5, 6, 7}.

Dora

hi
how can i get the co-ordinates of each node of a octagon circle around a central node having co-ordinate (0,0,0)
plz help me

 

[dipt]

thanx
it is really helpful to me.