On Numbers

Erik Max Francis max at alcyone.com
Tue Jan 17 03:53:43 CET 2006


Steven D'Aprano wrote:

> The square root of 1 is +1 (the negative root being 
> explicitly rejected). Pure mathematicians, who may be 
> expected to care whether the root is the integer 1 or 
> the real number 1, are unlikely to write 1**0.5, 
> prefering the squareroot symbol.
> 
> For the rest of us, including applied mathematicians, 
> 1**0.5 implies floating point, which implies the 
> correct answer is 1.0.
> 
> So I don't really know what point you are making. What 
> solution(s) for 1**0.5 were you expecting?

He's probably getting at the fact that if you're dealing with complex 
numbers, square root get a lot more complicated:

	http://mathworld.wolfram.com/SquareRoot.html

But still, that doesn't change the fact that x**0.5 as is meant here is 
the principal (positive) real square root, and that can be true whether 
your hierarchy of numeric types includes a complex type or not.

-- 
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
San Jose, CA, USA && 37 20 N 121 53 W && AIM erikmaxfrancis
   Walk into a room and make the / Whole interior inferior
   -- Ice Cube



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