All --

> As I understand it, computer languages differ in their implementation
> of the mod() function. I've heard some architectures differ, too, so
> that the same language (such as C or Perl) might behave differently on
> different machines (I'd be interested to know if this is really true).

Besides the Calendrical Calculations reference I originally sited,
here's another reference to troubles with mod, from [1], page 23:

    Commercial machines are usually deficient in their support of
    integer arithmetic. For example, they almost never produce the
    true quotient floor(x/y) and true remainder x mod y when x is
    negative or y is negative; ...

You can find [1] online at:

    http://www-cs-faculty.stanford.edu/~knuth/fasc1.ps.gz

I'd definitely suggest anyone who has not already read it get it and
read it. See especially the answer to exercise 2 of section 1.3.1' :)

Knuth's stuff on the MMIX simulator is very good as well (but, heck,
*everything* he writes is very good).


References:

  [1] Donald E. Knuth, *The Art of Computer Programming Fascicle 1:
      MMIX*. Addison-Wesley, 1999.


Regards,

-- Gregor
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   Gregor N. Purdy                          [EMAIL PROTECTED]
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