Re: Natural data type ?

[Georg Bauhaus <sb463ba@l1-hrz.uni-duisburg.de>]

Peter I. Hansen <pih@oek.dk> wrote:

: No, this is a misunderstanding. The natural numbers are defined to be 
: the numbers you can count to.

There exists a book, the author of which has defined the
natural numbers such that "You can count to 1, you can count to 2, 
: you can count to 3, ... and so forth." (Does there exist
a book on theretical computer science that defines N without 0?)

: You cannot count to Zero.
How many coins will this ticket vending machine throw out?
How do you answer that questions with N = {1,2,...}?

If you read characters into storage from some input
you count how many have arrived. There might be zero.
I like this very natural idea.

What is the neutral element when you want to do the very natural
thing of adding natural numbers? (O.K., that leads nowhere. But
you see an advantage, do you?)

OTOH, positive has a meaning outside mathematics.  And even if
you do not refer to Latin, take medicine.
A test may be positive, because there was at least one thing
that makes the doctors say so.

: 
: The question 'How many?' is the reason for defining other numbers than 
: natural.
: 'Q: How many apples did you eat ? A: 2 and a half (=2.5 a rational number)'.

That is dealt with by computers by introducing half-apples :-)

- Georg