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DSERKEZ
Jul 5th, 2003, 02:21 PM
According to the picture, I'd like to have the code to plot point "P" , (X,Y), coordinates.

Thanks in advance.

Regards

DSerkez

twanvl
Jul 5th, 2003, 03:12 PM
If C is at (0,0), then the condition:
x2/a2 + y2/b2 = 1
will be true for all points on the ellipse.
So for a given x:
y2/b2 = 1 - x2/a2
y2 = (1 - x2/a2) * b2
y = +/- sqrt((1 - x2/a2) * b2)

where +/- means that y can have two values, +... and -...., and sqrt is the square root (?0.5)

You could also calculate the ellipse based on:
r1 + r2 = 2(a-c) + 2c = 2a

DSERKEZ
Jul 6th, 2003, 08:47 AM
Hi and thank you for the reply.

But what I am trying to do is to move point "P" around the ellipse and connecting two lines (F1,F2) to P while moving.

I tried some things but did not work.


Thanks again.

NotLKH
Jul 6th, 2003, 12:21 PM
So, you mean something like this example progie, except for an ellipse, and not a sphere?

;)

DSERKEZ
Jul 7th, 2003, 09:43 AM
That's exactly what I needed.

Thank you Twanvl, thank you NotLKH.



Bye.