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Re: Java Source of Meiyan Hash Scrambler?

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Hi Lazyweb,

I have also seen this code already, thanks very much. And
Meiyan is said to be a variant of fnv. But problem with
your code samples is as follows:

     The checksum as you call it, is computed for
     a byte[] argument and returns an int.

But I need a scrambler which is based on the following
interface and still fast:

     The scrambler should take an int and
     return an int.

Now I see different problems with porting the byte[] solution.
Primarily that what looks as an efficient algorithm is suddently
not so efficient.

Just remember the number of arithmetic/bitwise ops:

     Oracle/Java: 2 Operations (>>>, ^)
         return h ^ (h >>> 16)

     murmur: 5 Operations (>>, ^, *, >>, ^)
         x ^= x >> 13;
         x *= 0x5bd1e995;
         return x ^ (x >> 15);

So if somebody has Meiyan AND its even shorter than
murmur in number of operations this would be great.

But a Meiyan which is longer in number of operations
would be also of interest to take a look.

Bye

Roedy Green schrieb:
> On Sun, 5 Jun 2016 17:22:07 -0700 (PDT), bursejan@gmail.com wrote:
>
>> Does somebody have Java code for the Meiyan hash scrambler.
>
> I have posted the code for a seven types of checksums
> with variants.
>
> see http://mindprod.com/jgloss/checksum.html
>
> Unfortunately, Meiyan is not among them.
>

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Thread

Java Source of Meiyan Hash Scrambler? bursejan@gmail.com - 2016-06-05 17:22 -0700
  Re: Java Source of Meiyan Hash Scrambler? Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-06-06 07:48 -0400
    Re: Java Source of Meiyan Hash Scrambler? Jan Burse <janburse@fastmail.fm> - 2016-06-06 14:13 +0200
      TreeBins Problem and Float/Double (Was: Java Source of Meiyan Hash Scrambler?) Jan Burse <janburse@fastmail.fm> - 2016-06-06 14:45 +0200
      Re: Java Source of Meiyan Hash Scrambler? Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-06-06 08:47 -0400
      Floating-point hash keys (Was: Java Source of Meiyan Hash Scrambler?) Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-06-06 12:02 -0400
        Re: Floating-point hash keys (Was: Java Source of Meiyan Hash Scrambler?) Roedy Green <inquiry@mindprod.com> - 2016-06-09 05:33 -0700
          Re: Floating-point hash keys (Was: Java Source of Meiyan Hash Scrambler?) Jan Burse <janburse@fastmail.fm> - 2016-06-09 16:27 +0200
  Re: Java Source of Meiyan Hash Scrambler? Roedy Green <inquiry@mindprod.com> - 2016-06-07 03:24 -0700
    Re: Java Source of Meiyan Hash Scrambler? Jan Burse <janburse@fastmail.fm> - 2016-06-07 15:38 +0200
    Re: Java Source of Meiyan Hash Scrambler? Jan Burse <janburse@fastmail.fm> - 2016-06-07 15:39 +0200
      Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Jan Burse <janburse@fastmail.fm> - 2016-06-07 15:42 +0200
        Re: Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Roedy Green <inquiry@mindprod.com> - 2016-06-09 05:29 -0700
          Re: Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Mike Amling <mamling@chaff.us> - 2016-06-09 08:00 -0500
            Re: Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Eric Douglas <e.d.programmer@gmail.com> - 2016-06-09 06:07 -0700
              Re: Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Jerry Stuckle <jstucklex@attglobal.net> - 2016-06-09 11:41 -0400
              Re: Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Roedy Green <inquiry@mindprod.com> - 2016-06-11 01:17 -0700
                Re: Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Daniel Pitts <usenet@coloraura.com> - 2016-06-11 12:31 -0700
                Re: Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Mike Amling <mamling@chaff.us> - 2016-06-12 15:42 -0500
                Re: Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Daniel Pitts <usenet@coloraura.com> - 2016-06-12 21:03 -0700
                Re: Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Roedy Green <inquiry@mindprod.com> - 2016-06-13 14:13 -0700
        Re: Sideremark II ( Re: Java Source of Meiyan Hash Scrambler?) Roedy Green <inquiry@mindprod.com> - 2016-06-10 14:11 -0700
      Re: Java Source of Meiyan Hash Scrambler? Roedy Green <inquiry@mindprod.com> - 2016-06-07 20:38 -0700
        Re: Java Source of Meiyan Hash Scrambler? Roedy Green <inquiry@mindprod.com> - 2016-06-09 05:15 -0700
          Re: Java Source of Meiyan Hash Scrambler? Jan Burse <janburse@fastmail.fm> - 2016-06-09 16:26 +0200
            Re: Java Source of Meiyan Hash Scrambler? Roedy Green <inquiry@mindprod.com> - 2016-06-12 02:28 -0700
              Re: Java Source of Meiyan Hash Scrambler? j4n bur53 <janburse@fastmail.fm> - 2016-06-12 12:03 +0200
                Re: Java Source of Meiyan Hash Scrambler? Andreas Leitgeb <avl@logic.at> - 2016-06-13 14:07 +0000
                Re: Java Source of Meiyan Hash Scrambler? Andreas Leitgeb <avl@logic.at> - 2016-06-13 14:17 +0000
                Re: Java Source of Meiyan Hash Scrambler? Andreas Leitgeb <avl@logic.at> - 2016-06-13 14:20 +0000
                Re: Java Source of Meiyan Hash Scrambler? j4n bur53 <janburse@fastmail.fm> - 2016-06-13 16:23 +0200

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