Greg Ewing <greg.ew...@canterbury.ac.nz> writes: > On 5/09/21 2:42 am, Hope Rouselle wrote: >> Here's what I did on this case. The REPL is telling me that >> 7.23 = 2035064081618043/281474976710656 > > If 7.23 were exactly representable, you would have got > 723/1000. > > Contrast this with something that *is* exactly representable: > >>>> 7.875.as_integer_ratio() > (63, 8) > > and observe that 7875/1000 == 63/8: > >>>> from fractions import Fraction >>>> Fraction(7875,1000) > Fraction(63, 8) > > In general, to find out whether a decimal number is exactly > representable in binary, represent it as a ratio of integers > where the denominator is a power of 10, reduce that to lowest > terms, and compare with the result of as_integer_ratio().
That makes perfect sense and answers my question. I appreciate it. -- https://mail.python.org/mailman/listinfo/python-list
