Re: % operator incompatibility...

From: Arjen Markus (arjen.markus_at_wldelft.nl)
Date: 03/30/04

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    Date: Tue, 30 Mar 2004 08:57:30 +0200

    Derk Gwen wrote:
    >
    > "Volker Hetzer" <volker.hetzer@ieee.org> wrote:
    > # Hi!
    > # When I do expr -1%360 in tcl I get 359.
    > # When I do this in C I get -1.
    > # Why the difference?
    >
    > Try Pascal and Ada as well. Everybody agrees when the numbers are positive.
    > They don't agree when either or both are negative.
    >

    Well, I just checked:

    Fortran (at least as of the Fortran 90 standard) defines two functions:
    MOD - the remainder function
    MODULO - the modulo function

    I think the confusion arises because people assume that the remainder
    is identical to modulo.

    Still, the solution offered by plain C is the worst: leave it up to the
    machine to select modulo or remainder ....

    Regards,

    Arjen

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