[racket] What is inexactness about?

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Wed Sep 1 09:29:15 EDT 2010

On Sep 1, 2010, at 9:14 AM, Stephen Bloch wrote:

> (since the only arithmetic involved is addition, subtraction, multiplication, and division), so the argument could be made that putting #i in there is distracting and pedantic.

I second this opinion (re pedantic). 

;; --- 

The #i indicates inexactness as far as computer arithmetic is concerned, that is, what the so-called 'machine' level arithmetic supplies. In HtDP terms, since this representation of information (numbers) and functions on it (arithmetic, etc) uses a fixed and finite amount of resources, you cannot represent all the numbers on the number line. Ergo, when you have some information (number) for which there is no piece of data on the machine (Number), you choose something close by. That's true for operations and for people mapping information to data. 

-- Matthias

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