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:


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/
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