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Subject: Re: SOLVE 4 NONLINEAR EQUATIONS (HELP PLEASE)
Date: Thu, 29 Apr 2010 21:03:04 +0000 (UTC)
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"GAURAV " <gsharda@engineering.uiowa.edu> wrote in message <hrcrc2$3me$1@fred.mathworks.com>...
> Hello Eveyone,
> 
> I am trying to get an ellipse passing through the four points I have which are not symmetric.
> So, I am using the equation (X-Xc)^2/(a^2) + (Y-Yc)^2/(b^2) =1
> 
> I have four points which wil go in X and Y of the equation above.
> Let the points be (a1,b1), (a2,b2), (a3,b3) and (a4,b4)..
> 
> How do I get a,b,Xc and Yc from this??
> 
> Please help me out. Really appreciate..
> 
> Thanks,
> Gaurav

  Are you certain the ellipse you are looking for has its major and minor axes aligned with the x and y axes?  If not, a minimum of five points is necessary.

Roger Stafford