On Tue, Mar 4, 2014 at 1:45 PM, Albert van der Horst <alb...@spenarnc.xs4all.nl> wrote: >>No, the Python built-in float type works with a subset of real numbers: > > To be more precise: a subset of the rational numbers, those with a denominator > that is a power of two.
And no more than N bits (53 in a 64-bit float) in the numerator, and the denominator between the limits of the exponent. (Unless it's subnormal. That adds another set of small numbers.) It's a pretty tight set of restrictions, and yet good enough for so many purposes. But it's a far cry from "all real numbers". Even allowing for continued fractions adds only some more; I don't think you can represent surds that way. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
