Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Ethan Furman <ethan@stoneleaf.us>
Newsgroups: comp.lang.python
Subject: Re: What is precision of a number representation?
Date: Mon, 11 Jul 2016 14:22:03 -0700
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On 07/11/2016 01:56 PM, Ben Finney wrote:

> Precision is not a property of the number. It is a property of the
> *representation* of that number.
>
> The representation “1×10²” has a precision of one digit.
> The representation “100” has a precision of three digits.
> The representation “00100” has a precision of five digits.
> The representation “100.00” also has a precision of five digits.

Your first, second, and fourth example have zeroes to the right, and I 
understand them just fine.

Your third example has zeroes to the left, and you haven't explained how 
00100 is more precise than 100.  I mean, if somebody told me that one 
hundred was closer to one hundred than it was to ten thousand I would 
have to say "D'oh!"

> We gain clarity of speech: we distinguish the different aspects (how
> many digits of this representation are actually claimed to represent the
> number?) communicated by a representation.

Nope, still not clear to me.  :(

--
~Ethan~