On 19 Nov, 18:26, Robert Bradshaw <[EMAIL PROTECTED]>
wrote:
> On Nov 19, 2008, at 10:18 AM, John H Palmieri wrote:
>
>
>
>
>
> > The documentation for the nth_root method for finite fields (repeated
> > in each of the files sage/structure/element.pyx, sage/rings/
> > finite_field_element.py, and sage/rings/finite_field_givaro.pyx) says
> > this:
>
> > INPUT:
> > n -- integer >= 1 (must fit in C int type)
> > extend -- bool (default: True); if True, return a square
> > root in an extension ring, if necessary. Otherwise,
> > raise a ValueError if the square is not in the base
> > ring.
> > all -- bool (default: False); if True, return all square
> > roots of self, instead of just one.
>
> > OUTPUT:
> > If self has an nth root, returns one (if all == False) or a
> > list of
> > all of them (if all == True). Otherwise, raises a
> > ValueError (if
> > extend = False) or a NotImplementedError (if extend =
> > True).
>
> > The entirety of the code dealing with 'extend' is this:
>
> > if extend:
> > raise NotImplementedError
>
> > Should the 'extend' option be removed altogether, or should it be left
> > in with a big warning saying that it's not implemented? (Or is
> > someone out there willing to implement it?)
>
> > (The same goes for the square_root method in finite_field_element.py.
> > The code for the sqrt method in finite_field_givaro.pyx is similar,
> > but the extend option, while present, isn't documented.)
>
> > I can open up a ticket for this, but it would be nice to have a
> > suggestion about which direction to go in the short term -- remove the
> > option or document the fact that it's not implemented -- to go on the
> > ticket.
>
> I think it's better to have the not implemented error. The signature
> of this function is modeled after the square root,
So is the docstring, rather too closely!
and it is handy to
> be able to rely on it being consistent across all types. For example,
> if I were writing the nth root method of a power series, I might want
> to take the nth root of the constant coefficient, and could just pass
> it the extend option that I got. Removing this option means I'd have
> to check whether or not the extend option were valid, or get a (less
> clear) type error when running the code.
>
> - Robert
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to sage-devel@googlegroups.com
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at http://groups.google.com/group/sage-devel
URLs: http://www.sagemath.org
-~----------~----~----~----~------~----~------~--~---
