Numeric literals in other than base 10 - was Annoying octal notation

James Harris james.harris.1 at googlemail.com
Sun Aug 23 23:45:39 CEST 2009


On 23 Aug, 21:55, James Harris <james.harri... at googlemail.com> wrote:

...

> >  However for floating point you
> > need at least three letters because a floating point number has
> > three parts: the fixed point point, the exponent base, and the
> > exponent.  Now we can represent the radices of the individual
> > parts with the 'r'scheme, e.g., 2r101001, but we need separate
> > letters to designate the exponent base and the exponent.  B and E
> > are the obvious choices, though we want to be careful about a
> > confusion with 'b' in hex.  For example, using 'R',
>
> > 3R20.1B2E16Rac
>
> Ooh err!
>
> > is 20.1 in trinary (6 1/3) times 2**172 (hex ac).
>
> > I grant that this example looks a bit gobbledegookish,
>
> You think? :-)
>
> > but normal
> > usage would be much simpler.  The notation doesn't handle
> > balanced trinary; however I opine that balanced trinary requires
> > special notation.
>
> When the programmer needs to construct such values how about allowing
> him or her to specify something like
>
>   (20.1 in base 3) times 2 to the power of 0xac
>
> Leaving out how to specify (20.1 in base 3) for now this could be
>
>   (20.1 in base 3) * 2 ** 0xac

Using the suggestion from another post would convert this to

  0.(3:20.1) * 2 ** 0xac

>
> The compiler could convert this to a constant.




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