deriving from float or int

[gene tani]

Russ wrote:
> Does it ever make sense to derive a class from a basic type such as
> float or int? Suppose, for example, that I want to create a class for
> physical scalars with units. I thought about deriving from float, then
> adding the units. I played around with it a bit, but it doesn't seem to
> work very well. Am I missing something here? Thanks.

you could look at how sciPy does it:
http://starship.python.net/~hinsen/ScientificPython/