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Q.Ronnie August 16, 2000 05:01

Circumference of Ellipse
 
Hello.

Is there anyone to know a formula to determine the circumference of ellipse(x2/a2+y2/b2=1).

Thanks in advance.

E.Buchanan August 16, 2000 06:01

Re: Circumference of Ellipse
 
have a look at http://forum.swarthmore.edu/dr.math/...q.ellipse.html

Daniel Jaeggi August 24, 2000 06:56

Re: Circumference of Ellipse
 
There is a neat approximation which has a maximum error of 0.4%. After Roger Maertens.

Perimeter = ((a^y+b^y)^(1/y))*4

where a,b = major/minor semi axis y = const = ln(2)/(ln(pi/2))

Hope that's helpful!

Or you could always do a little numerical integration.

dan


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