[bcc'ing numpy-discussion. Comments should probably try to stay on the python-3000 list.]
On 4/25/07, Josiah Carlson <[EMAIL PROTECTED]> wrote: > Are the base number operations in Python all that difficult to > understand? Do we really need to add mathematical formalism into > Python's type system before people understand the meaning of X * Y? > Because all I really see this doing is confusing the hell out of people > who aren't mathematicians; I'm a theoretical computer scientist and I > had to try to think for a moment to verify that all of those were really > necessary to separate the cases. > > I really do understand wanting to be able to ask "is operation X > supported for values Y and Z", but is this really necessary for numbers? If you don't want to use the full power of the system, nothing forces you to. If someone doesn't know what a Ring or a complex number is, they can just check for Real and rely on the same operations, at the small cost of overconstraining their inputs. One reason I'm suggesting splitting the classes into the "algebra" and "numbers" modules is so that people who don't know or care about the algebra can rely on just "numbers" and still get nearly all of the benefits. However, I think it's important to provide a framework for people who want to do more powerful things. If you write a function that can take an arbitrary ring, it should Just Work on a python int, or any other Complex subclass, without you having to check for a lot of operations separately. The Haskell98 numerical hierarchy actually does start at Num, ignoring the algebraic structures underneath, and it draws a lot of criticism for it. That does mean that the names and documentation in the numbers module need to be as clear as we can make them for non-mathematical audiences. I'm certainly open to suggestions on that front. -- Namasté, Jeffrey Yasskin _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
