Steven D'Aprano <steve+comp.lang.pyt...@pearwood.info>: >> >>> Rational(2).sqrt() * Rational(2).sqrt() == Rational(2) >> False > > Square root of 2 is not a rational number.
Nobody said it was. It's just that even "arbitrary-precision" rational numbers wouldn't free you from the issues of floating-point numbers. The Decimal number class won't do it, either, of course. On the other hand, floating-point numbers are perfect whenever you deal with science and measurement. And when you deal with business (= money), integers are the obvious choice. I would venture to say that the real applications for Decimal are very rare. In practice, I'm afraid, people with rather a weak understanding of numbers and computation might gravitate toward Decimal unnecessarily. Marko -- https://mail.python.org/mailman/listinfo/python-list
