In message <[EMAIL PROTECTED]>, Dan Cross writes:
>On Thu, Dec 15, 2005 at 10:53:06PM -0600, erik quanstrom wrote:
>> | Please note that this definition of DIV and MOD differs from the
>> | definition given in [M. Reiser, N. Wirth. Programming in Oberon. p.
>> | 36]:
>> | x  = (x DIV y) * y + (x MOD y), and
>> | 0 <= (x MOD y) < y
>    ^^^^^^^^^^^^^^^^^^
>> | 
>> | So, what *is* -5 MOD 3?
>> | 
>> 
>> -2
>
>Are you sure?  It looks to me more than it'd be +1.  Wirth's definition
>above would tend to indicate that x MOD y is always positive, unless I'm

This also matches Knuth's in Vol 1.  He states it as:

x mod y = x - y * floor( x / y )

and then observes that the mod follows the sign of y and that
the magnitude of the mod is strictly less than that of y.

Brian L. Stuart

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