Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.python > #37347

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

Show key headers only | View raw

On 01/22/2013 03:30 PM, Leonard, Arah wrote:
>> 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.
>>
>
> Actually, to give credit where it's due, it wasn't me.  I just modified someone else's interesting solution in this thread and added the silly limit of 10000 to it.
>

That's okay.  The OP doesn't seem to know anything about programming, or 
about information theory, so the fact you gave a single line that 
actually "works" must be extraordinarily valuable to him.  When he was 
trying to use the md5 module, I gave him the hints about his five 
programming errors, and was about to expand on it when i noticed his 4 
digit limitation.

>> In any case, the likelihood of a hash collision for any non-trivial website is substantial.
>>
>
> Exactly.  Four digits is hardly enough range for it to be even remotely safe.  And even then range isn't really the issue as technically it just improves your odds.
>
> The results of a modulus operator are still non-unique no matter how many digits are there to work with ... within reason.  Statistically anyone who buys a ticket could potentially win the lottery no matter how bad the odds are.  ;)
>
> And now back to the OP, I'm still confused on this four-digit limitation.  Why isn't the limitation at least adhering to a bytelength like byte/short/long?  Is this database storing a string of characters instead of an actual number?  (And if so, then why not just block out 255 characters instead of 4 to store a whole path?  Or at the very least treat 4 characters as 4 bytes to greatly increase the numeric range?)
>

I wish I had done the internet search earlier.  This name 'ferrous 
cranus' is a pseudonym of various trolls, and anybody who'd adopt it 
isn't worth our time.

Thanks to Alan Spence for spotting that.  I'll plonk 'ferrous cranus' now.


-- 
DaveA

Back to comp.lang.python | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

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

csiph-web