From: jzakiya <jzakiya@...>
Date: 2010-06-03T01:50:07+09:00
Subject: Re: Square Root

On May 29, 3:33 pm, Angus Hammond <angushamm...@hotmail.co.uk> wrote:
> Thanks I had tried require complex and Math::sqrt but only separately.
> Thanks again.
> Angus
>
> On 29/05/10 21:03, Jean-Julien Fleck wrote:
>
> > Hello Angus,
>
> > 2010/5/29 Angus Hammond<angushamm...@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,
>
>

FYI. For more extensive (and easy) way to add the ability
to find the nth roots of all numerical types check out
my Roots module here:

http://gist.github.com/422636

Jabari