Subj : Re: Reversing a number
To   : comp.programming
From : Willem
Date : Thu Sep 15 2005 05:25 pm

Antoon wrote:
) Op 2005-09-15, Willem schreef <willem@stack.nl>:
)> I disagree.  The problem only states what the end-result should be and
)> does NOT specify how it should be done.
)
) The statement of the end result implies that is about numerals,
) strings representations of numbers, and not about numbers itself.

So what ?  That doesn't mean you're suddenly allowed to interpret
the problem as if it species how it should be solved.

)> It is simpler in the very real sense that no strings are involved.
)> ('strings' as defined by the programming language.)
)> The only thing that is involved is digits, and base-10 representation.
)
) base-10 representation says it all, this is about the representations
) in a particular base. It is not about the numbers themselves.

So what ?
Lemme ask you a question:  Suppose I have an algorithm that solves the
following problem:

Return (as a number) the base-10 digits of the input number, repeated
twice.  (That is: f(123) = 123123, f(15) = 1515, f(100200) = 100200100200)

Would you claim that that algorithm involves strings ?


)> The algorithm described (it's not my algorithm by the way) extracts
)> base-10 digits from one number and injects it into another, one by one.
)> That's all it does.  No strings.
)
) Extracting base-10 digits is conceptually working with strings.
) That you keep the digits as a number because that works easier
) changes nothing about that. Digits is what numerals in particular
) notations have. Numbers don't have digits.
)
) Yes your algorithm works with numbers, but when you explain what
) it does you are constantly reffering to numeral concepts and
) not to number concepts, thus betraying that conceptually you
) are working with strings.

That I'm using the numeral concept 'digit' does not mean that
I necessarily have to also use the numeral concept 'string'.

Furthermore, even if I had to use strings to explain *why* the
algorithm works, that *still* would not mean that the algorithm
*uses* strings.

By the way, what part of 'it's not my algorithm' did you not understand ?


SaSW, Willem
-- 
Disclaimer: I am in no way responsible for any of the statements
            made in the above text. For all I know I might be
            drugged or something..
            No I'm not paranoid. You all think I'm paranoid, don't you !
#EOT

.