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Re: Negating a number

by Illuminatus (Curate)
on Mar 04, 2009 at 17:24 UTC ( #748246=note: print w/replies, xml ) Need Help??

in reply to Negating a number

What is right, indeed... Depends on what you are trying to do. Please read 2's compleent. If you are doing ordinary arithmetic, then what you are doing is probably what you want. If you are doing something like calculating a TCP checksum, then the other method is closer to (but not exactly) what you want.

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Re^2: Negating a number
by ramrod (Curate) on Mar 04, 2009 at 17:33 UTC
    Illuminatus is going the right direction.
    Your first example yields the binary of negative seven.
    The second example is the negation of the bits of a hex seven.