in reply to Digest (checksum) Algorithm for 12 Decimal Digits?

use a 16 bit algorithm, and use only 12 of them

Oha

update: sorry i re-read. use any algorithm which give you more information, and truncate this information to the data you need.

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Re^2: Digest (checksum) Algorithm for 12 Decimal Digits?
by cmv (Chaplain) on Oct 05, 2007 at 16:01 UTC
    Doesn't it mean that if I truncate data, I'll be exposing myself to higher risk of having different data generating the exact same digest value?

    I believe that is true, but maybe the risk is still so small as to be negligable!?!

[reply]
      suppose you have a 3 bit hash function: the best is if all the value populate the 8 possibilities in equal density. now you remove 1 bit. it means that you have only 4 buckets now, and being the result of the union of two who are equal density, they are equal density.
      IOW, if the hash function you used was good, the result is good.

      Oha

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