Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » sci.math.* » sci.math

Topic: Is there a name for this notation?
Replies: 8   Last Post: Oct 9, 2011 9:17 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Kaba

Posts: 289
Registered: 5/23/11
Re: Is there a name for this notation?
Posted: Oct 9, 2011 8:52 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

A N Niel wrote:
> In article <4e919166$0$29981$c3e8da3$5496439d@news.astraweb.com>,
> Steven D'Aprano <steve+comp.lang.python@pearwood.info> wrote:
>

> >[...]>
> > You'd need either a digit for 100, or some notation for grouping digits.
> > E.g.:
> >
> > 2^10 => A
> > 2^11 => B
> > 2^12 => C
> > ...
> >
> > but since we can't realistically have an infinite number of unique symbols,
> > a grouping notation might be better:
> >
> > 2^100 + 2^50 + 2^10 + 2^2 = (100)(50)(10)2

>
> Since it is just a set anyway, maybe {100,50,10,2}


In the case of "base 2", this can be seen as a sparse form of the
traditional base-2 representation. Let I subset NN. Then the value of I
is given by

V(I) = sum_{i in I} 2^i,

i.e. the set I encodes the positions of the 1-bits, rather than giving a
"dense" tuple of coefficients where some elements might be 0. Higher
bases probably sacrifice some property, possibly uniqueness.

--
http://kaba.hilvi.org



Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.