Zentrader wrote: > You can use Python's decimal class if floating point arithmetic is not > exact enough
This is a misleading statement. While it's true that decimal can be more precise in the sense that smaller fractions are representable, the underlying problem of certain values not being representable properly & leading to rounding errors still exists: >>> import decimal >>> d = decimal.Decimal >>> d("1") / d("3") Decimal("0.3333333333333333333333333333") >>> otrd = d("1") / d("3") >>> otrd * 3 Decimal("0.9999999999999999999999999999") >>> otrd * d("3") Decimal("0.9999999999999999999999999999") >>> Diez -- http://mail.python.org/mailman/listinfo/python-list