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Subject: Re: sqrt complex
Date: Tue, 11 May 2010 17:04:05 +0000 (UTC)
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"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <hsc0es$988$1@fred.mathworks.com>...
> I read at the help and doc but I could not find any specification of SQRT for complex numbers.
> 
> It seems the output keeps the same sign of the imaginary part as the input, and the discontinuity (in the complex plane) is the negative real axis. This is what I want, but I love to see it documented somewhere.
> 
> Any opinion?
===============

Probably the closest thing you can get right now is

doc angle

After some experimentation it is pretty clear that the underlying algorithm is

sqrt(A)=sqrt(abs(A))*exp(-i*angle(A)/2);