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Re: Converting a string to a number by using INT (no hash method)

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Date Tue, 22 Jan 2013 14:08:14 -0500
From Dave Angel <d@davea.name>
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Subject Re: Converting a string to a number by using INT (no hash method)
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On 01/22/2013 01:37 PM, Ferrous Cranus wrote:
>
>>  <snip>
>>
>
> ==============================================
> pin = int( htmlpage.encode("hex"), 16 ) % 10000
> ==============================================
>
> Can you please explain the differences to what you have posted opposed to this perl coding?
>
> ==============================================
> foreach my $ltr(@ltrs){
>          $hash = ( $hash + ord($ltr)) %10000;
> ==============================================
>
> I want to understand this and see it implemented in Python.
>

The perl code will produce the same hash for  "abc.html" as for 
"bca.html"  That's probably one reason Leonard didn't try to 
transliterate the buggy code.

In any case, the likelihood of a hash collision for any non-trivial 
website is substantial.  As I said elsewhere, if you hash 100 files you 
have about a 40% chance of a collision.

If you hash 220 files, the likelihood is about 90%

-- 
DaveA

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Thread

Converting a string to a number by using INT  (no hash method) Ferrous Cranus <nikos.gr33k@gmail.com> - 2013-01-22 08:15 -0800
  RE: Converting a string to a number by using INT  (no hash method) "Leonard, Arah" <Arah.Leonard@bruker-axs.com> - 2013-01-22 16:27 +0000
    Re: Converting a string to a number by using INT  (no hash method) Ferrous Cranus <nikos.gr33k@gmail.com> - 2013-01-22 09:02 -0800
      RE: Converting a string to a number by using INT  (no hash method) "Leonard, Arah" <Arah.Leonard@bruker-axs.com> - 2013-01-22 17:24 +0000
        Re: Converting a string to a number by using INT  (no hash method) Ferrous Cranus <nikos.gr33k@gmail.com> - 2013-01-22 09:39 -0800
          Re: Converting a string to a number by using INT (no hash method) John Gordon <gordon@panix.com> - 2013-01-22 18:36 +0000
          Re: Converting a string to a number by using INT  (no hash method) Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-01-22 17:22 -0500
        Re: Converting a string to a number by using INT  (no hash method) Ferrous Cranus <nikos.gr33k@gmail.com> - 2013-01-22 09:39 -0800
        Re: Converting a string to a number by using INT  (no hash method) Ferrous Cranus <nikos.gr33k@gmail.com> - 2013-01-22 10:37 -0800
          Re: Converting a string to a number by using INT  (no hash method) Michael Torrie <torriem@gmail.com> - 2013-01-22 12:02 -0700
            Re: Converting a string to a number by using INT  (no hash method) Ferrous Cranus <nikos.gr33k@gmail.com> - 2013-01-22 11:28 -0800
              Re: Converting a string to a number by using INT  (no hash method) Alan Spence <alan.spence@ntlworld.com> - 2013-01-22 20:00 +0000
            Re: Converting a string to a number by using INT  (no hash method) Ferrous Cranus <nikos.gr33k@gmail.com> - 2013-01-22 11:28 -0800
              Re: Converting a string to a number by using INT (no hash method) John Gordon <gordon@panix.com> - 2013-01-22 20:40 +0000
                Re: Converting a string to a number by using INT (no hash method) Ferrous Cranus <nikos.gr33k@gmail.com> - 2013-01-23 00:44 -0800
          Re: Converting a string to a number by using INT  (no hash method) Dave Angel <d@davea.name> - 2013-01-22 14:08 -0500
          RE: Converting a string to a number by using INT  (no hash method) "Leonard, Arah" <Arah.Leonard@bruker-axs.com> - 2013-01-22 20:30 +0000
          Re: Converting a string to a number by using INT  (no hash method) Dave Angel <d@davea.name> - 2013-01-22 15:43 -0500
        Re: Converting a string to a number by using INT  (no hash method) Ferrous Cranus <nikos.gr33k@gmail.com> - 2013-01-22 10:37 -0800
    Re: Converting a string to a number by using INT  (no hash method) Ferrous Cranus <nikos.gr33k@gmail.com> - 2013-01-22 09:02 -0800
  Re: Converting a string to a number by using INT  (no hash method) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-01-22 16:27 +0000
  Re: Converting a string to a number by using INT  (no hash method) Dave Angel <d@davea.name> - 2013-01-22 11:40 -0500
    Re: Converting a string to a number by using INT (no hash method) alex23 <wuwei23@gmail.com> - 2013-01-22 17:32 -0800
      Re: Converting a string to a number by using INT (no hash method) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-01-23 03:02 +0000
        Re: Converting a string to a number by using INT (no hash method) alex23 <wuwei23@gmail.com> - 2013-01-22 19:59 -0800
  Re: Converting a string to a number by using INT  (no hash method) "D'Arcy J.M. Cain" <darcy@druid.net> - 2013-01-22 12:04 -0500

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