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Groups > comp.lang.python > #92271

Re: Testing random

From Thomas 'PointedEars' Lahn <PointedEars@web.de>
Newsgroups comp.lang.python
Subject Re: Testing random
Date 2015-06-07 18:36 +0200
Organization PointedEars Software (PES)
Message-ID <1656356.OjxBvjpJ5d@PointedEars.de> (permalink)
References <87oaksowwg.fsf@Equus.decebal.nl> <1451048.pW9z17ilMA@PointedEars.de> <mailman.242.1433677915.13271.python-list@python.org> <3158703.Lr4HFMbMOd@PointedEars.de> <mailman.257.1433694323.13271.python-list@python.org>

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Chris Angelico wrote:

> On Mon, Jun 8, 2015 at 1:51 AM, Thomas 'PointedEars' Lahn
> <PointedEars@web.de> wrote:
>> Chris Angelico wrote:
>>
>>> On Sun, Jun 7, 2015 at 8:40 PM, Thomas 'PointedEars' Lahn
>>> <PointedEars@web.de> wrote:
>>>> Cecil Westerhof wrote:
>>>>> I wrote a very simple function to test random:
>>>>>     def test_random(length, multiplier = 10000):
>>>>>         number_list = length * [0]
>>>>>         for i in range(length * multiplier):
>>>>>             number_list[random.randint(0, length - 1)] += 1
>>>>>         minimum = min(number_list)
>>>>>         maximum = max(number_list)
>>>>>         return (minimum, maximum, minimum / maximum)
>>>>
>>>> As there is no guarantee that every number will occur randomly, using a
>>>> dictionary at first should be more efficient than a list:
>>>
>>> Hmm, I'm not sure that's actually so. His code is aiming to get
>>> 'multiplier' values in each box; for any serious multiplier (he starts
>>> with 10 in the main code), you can be fairly confident that every
>>> number will come up at least once.
>>
>> The wording shows a common misconception: that random distribution would
>> mean that it is guaranteed or more probable that every element of the set
>> will occur at least once.  It is another common misconception that
>> increasing the number of trials would increase the probability of that
>> happening.  But that is not so.
> 
> The greater the multiplier, the lower the chance that any element will
> have no hits.

Wrong.

> [ex falso quodlibet]

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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Thread

Testing random Cecil Westerhof <Cecil@decebal.nl> - 2015-06-07 08:27 +0200
  Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 12:40 +0200
    Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-07 21:51 +1000
      Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 17:51 +0200
        Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 02:25 +1000
          Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 18:36 +0200
            Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 02:44 +1000
              Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 20:23 +0200
                Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 04:52 +1000
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 21:41 +0200
                Re: Testing random Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2015-06-07 22:08 +0300
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 21:29 +0200
                Re: Testing random random832@fastmail.us - 2015-06-07 15:44 -0400
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 22:09 +0200
                Re: Testing random random832@fastmail.us - 2015-06-07 16:41 -0400
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 22:59 +0200
                Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-08 11:26 +1000
                Re: Testing random random832@fastmail.us - 2015-06-07 21:34 -0400
                Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 11:42 +1000
                Re: Testing random MRAB <python@mrabarnett.plus.com> - 2015-06-08 02:49 +0100
                Re: Testing random random832@fastmail.us - 2015-06-07 21:57 -0400
                Re: Testing random Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2015-06-08 10:40 +0300
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-10 19:03 +0200
                Re: Testing random sohcahtoa82@gmail.com - 2015-06-10 10:52 -0700
                Re: Testing random Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2015-06-10 23:00 +0300
                Re: Testing random Ian Kelly <ian.g.kelly@gmail.com> - 2015-06-10 12:02 -0600
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-12 23:32 +0200
                Re: Testing random alister <alister.nospam.ware@ntlworld.com> - 2015-06-12 21:46 +0000
                Re: Testing random random832@fastmail.us - 2015-06-12 17:52 -0400
                Re: Testing random Ian Kelly <ian.g.kelly@gmail.com> - 2015-06-12 16:00 -0600
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-13 00:09 +0200
                Re: Testing random sohcahtoa82@gmail.com - 2015-06-12 15:55 -0700
                Re: Testing random random832@fastmail.us - 2015-06-12 18:57 -0400
                Re: Testing random Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-06-13 08:53 +0100
                Re: Testing random random832@fastmail.us - 2015-06-10 14:26 -0400
                Re: Testing random Ned Batchelder <ned@nedbatchelder.com> - 2015-06-07 14:21 -0700
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-16 21:18 +0200
                Re: Testing random random832@fastmail.us - 2015-06-16 16:23 -0400
                Re: Testing random Ned Batchelder <ned@nedbatchelder.com> - 2015-06-16 13:48 -0700
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-16 23:57 +0200
                Re: Testing random sohcahtoa82@gmail.com - 2015-06-16 15:30 -0700
                Re: Testing random Ian Kelly <ian.g.kelly@gmail.com> - 2015-06-16 16:58 -0600
                Re: Testing random Laura Creighton <lac@openend.se> - 2015-06-17 11:28 +0200
                Re: Testing random Ned Batchelder <ned@nedbatchelder.com> - 2015-06-16 16:26 -0700
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-17 01:45 +0200
                Re: Testing random sohcahtoa82@gmail.com - 2015-06-16 17:36 -0700
                Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-17 11:01 +1000
                Re: Testing random Ethan Furman <ethan@stoneleaf.us> - 2015-06-16 18:32 -0700
                Re: Testing random Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-06-17 09:41 +0100
                Re: Testing random Grant Edwards <invalid@invalid.invalid> - 2015-06-17 14:04 +0000
                Re: Testing random Ian Kelly <ian.g.kelly@gmail.com> - 2015-06-17 09:01 -0600
                Re: Testing random MRAB <python@mrabarnett.plus.com> - 2015-06-17 01:42 +0100
                Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-17 08:53 +0200
                Re: Testing random Christian Gollwitzer <auriocus@gmx.de> - 2015-06-17 09:22 +0200
                Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-17 17:28 +1000
                Re: Testing random Tim Golden <mail@timgolden.me.uk> - 2015-06-17 08:30 +0100
                Re: Testing random Cecil Westerhof <Cecil@decebal.nl> - 2015-06-17 11:57 +0200
                Re: Testing random Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-06-17 01:36 +0000
                Re: Testing random Laura Creighton <lac@openend.se> - 2015-06-17 12:33 +0200
                Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-17 22:47 +1000
                Re: Testing random Laura Creighton <lac@openend.se> - 2015-06-17 15:50 +0200
                Re: Testing random Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-06-17 01:35 +0000
                Re: Testing random Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2015-06-17 07:41 +0300
                Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-08 11:11 +1000
            Re: Testing random Ian Kelly <ian.g.kelly@gmail.com> - 2015-06-07 11:07 -0600
            Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 03:20 +1000
            Re: Testing random "C.D. Reimer" <chris@cdreimer.com> - 2015-06-07 10:36 -0700
            Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-08 04:28 +1000
              Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 04:40 +1000
        Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-08 04:24 +1000
  Re: Testing random Jonas Wielicki <jonas@wielicki.name> - 2015-06-07 12:41 +0200
  Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-07 22:52 +1000
    Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-07 23:06 +1000
    Re: Testing random Peter Otten <__peter__@web.de> - 2015-06-07 15:35 +0200
      Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 18:36 +0200
        Re: Testing random Peter Otten <__peter__@web.de> - 2015-06-07 18:48 +0200
          Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 22:15 +0200
      Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-08 11:35 +1000
  Re: Testing random Christian Gollwitzer <auriocus@gmx.de> - 2015-06-07 14:53 +0200
  Re: Testing random Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2015-06-07 11:04 -0400

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