From: Jean-Julien Fleck <jeanjulien.fleck@...>
Date: 2010-05-30T05:03:19+09:00
Subject: Re: Square Root

Hello Angus,

2010/5/29 Angus Hammond <angushammond@hotmail.co.uk>:
> Is there a way to get an accurate square root?
> This means that a negative number should return the appropriate complex
> number. I have been having some trouble with this in a program that solves
> quadratic equations recently. Ideally but not necessarily it should be able
> to get the square root of complex numbers as well.
> NB Neither -2**0.5 or Math::sqrt(-2) return appropriate answers. (-2 and an
> error respectively)

require 'complex'
include Math
c = Complex(-2,0)
sqrt(c)

>> require 'complex'
=> true
>> include Math
=> Object
>> c = Complex(-2,0)
=> Complex(-2, 0)
>> sqrt(c)
=> Complex(0.0, 1.4142135623731)

Cheers,

-- 
JJ Fleck
PCSI1 Lycée Kléber