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Groups > comp.os.linux.advocacy > #383651
| From | deplorable owl <owl@rooftop.invalid> |
|---|---|
| Newsgroups | comp.os.linux.advocacy |
| Subject | Re: Where are you, sdb? I have something fun for your little morons to try |
| Date | 2016-12-11 07:09 +0000 |
| Organization | O.W.L. |
| Message-ID | <ahjblc00g.a3i@rooftop.invalid> (permalink) |
| References | (10 earlier) <o2imdt$q5o$1@news.albasani.net> <ahjgepg00q.ga@rooftop.invalid> <o2iqn3$5n7$1@news.albasani.net> <ahjgjb00ag.it@rooftop.invalid> <20161211075236.12628ebe@maxa-pc> |
Melzzzzz <mel@zzzzz.com> wrote:
> On Sun, 11 Dec 2016 06:49:30 +0000 (UTC)
> deplorable owl <owl@rooftop.invalid> wrote:
>
>> Melzzzzz <Melzzzzz@zzzzz.com> wrote:
>> > On 11/12/16 06:55 AM, deplorable owl wrote:
>> >> Melzzzzz <Melzzzzz@zzzzz.com> wrote:
>> >>> On 11/12/16 05:27 AM, deplorable owl wrote:
>> >>>> Melzzzzz <Melzzzzz@zzzzz.com> wrote:
>> >>>>> On 11/12/16 05:00 AM, deplorable owl wrote:
>> >>>>>> Melzzzzz <mel@zzzzz.com> wrote:
>> >>>>>>> On Sat, 10 Dec 2016 19:56:49 +0000 (UTC)
>> >>>>>>> deplorable owl <owl@rooftop.invalid> wrote:
>> >>>>>>>
>> >>>>>>>> Melzzzzz <Melzzzzz@zzzzz.com> wrote:
>> >>>>>>>>> On 10/12/16 07:25 AM, deplorable owl wrote:
>> >>>>>>>>>> Melzzzzz <Melzzzzz@zzzzz.com> wrote:
>> >>>>>>>>>>
>> >>>>>>>>>> BTW, what's the proper approach to randomizing such a huge
>> >>>>>>>>>> number of values? (A large enough pool of seconds so that
>> >>>>>>>>>> randoms would have a good chance of falling on 100,000
>> >>>>>>>>>> different days).
>> >>>>>>>>>>
>> >>>>>>>>>>
>> >>>>>>>>> You don't have to just filter out dupes ;p
>> >>>>>>>>> It is not needed to have 100000k uniques at all.
>> >>>>>>>>
>> >>>>>>>> Yeah, but filtering is just to get uniques. Say you want
>> >>>>>>>> 100000 unique days using random second values, minimizing
>> >>>>>>>> dups and generating exactly 100000 values, how would you
>> >>>>>>>> approach that?
>> >>>>>>>
>> >>>>>>> I would generate 100000 days in order, then shuffle.
>> >>>>>>>
>> >>>>>>
>> >>>>>> Yes, that's easy, but it dodges the pre-generation randomizing
>> >>>>>> problem rather than addressing it, and also requires generation
>> >>>>>> of a full 8.64 billion numbers then modulo 86400 to get 100000
>> >>>>>> unique sequential days before shuffling.
>> >>>>>
>> >>>>> Hm, I don't get it ;)
>> >>>>> Just create 100k dates and then shuffle, what's the problem?
>> >>>>>
>> >>>>
>> >>>> It's not really about dates. It's about the rand problem that
>> >>>> arises if you randomize 100,000 time_t values with the goal of
>> >>>> 100,000 unique DD-MM-YYYY values. Consider it generically.
>> >>>> Forget that it's a date function, and assume that you have a
>> >>>> pool of input values for which output values only change for
>> >>>> every 86400 inputs. You want to get 100,000 random (but
>> >>>> hopefully unique) outputs given only 100,000 randomly chosen
>> >>>> inputs. How do you randomize your inputs where the input pool is
>> >>>> minimum 8.64 billion to guarantee that you *might* get 100,000
>> >>>> unique outputs.
>> >>>>
>> >>>>
>> >>> You first get starting date and ending date. Then generate all
>> >>> possible dates in range. Then randomly pick required number of
>> >>> dates from that list..
>> >>
>> >> Again, forget that it's dates. Say you have a step function f(x)
>> >> that only changes values for every 86400 values of x (x +/-
>> >> integers). You don't get to select random f(x). You must select
>> >> 100000 random x and get 100000 hopefully unique f(x). What does
>> >> your rand routine look like?
>> > Same answer.
>> >
>>
>> Did you note this part: "You don't get to select random f(x)" ?
>> You must pick 100000 random x, not 100000 random f(x).
>>
>
> It all boils down to same. If you dont have pool of unique numbers to
> pick, you can't produce unique numbers... random functions are random...
>
True, but you can A) choose a big enough pool, or B) choose an efficient
randomizing algorithm. It's easy enough to get a big pool and reduce
the dupes to zero. I would like to have your take on a randomizing
algorithm that would not require a pool of seconds spanning 70,000
years.
This is my approach, and it's far from ideal:
for(i=0;i<100000;i++)
{
rannum[i]=random()%INT_MAX+(-INT_MAX/2);
rannum[i]*=random()%(atoi(argv[1]));
}
anon@lowtide:~/code/dfsdates$ ./dupes 1
generated 100000 random time_t values to get 100000 days
day dupes: 99999
sorted:
rannum[0]: 0: 31-Dec-1969
rannum[99999]: 0: 31-Dec-1969
anon@lowtide:~/code/dfsdates$ ./dupes 5
generated 100000 random time_t values to get 100000 days
day dupes: 4081
sorted:
rannum[0]: -4294563276: 29-Nov-1833
rannum[99999]: 4294923596: 06-Feb-2106
anon@lowtide:~/code/dfsdates$ ./dupes 9
generated 100000 random time_t values to get 100000 days
day dupes: 1231
sorted:
rannum[0]: -8587334984: 16-Nov-1697
rannum[99999]: 8589040944: 05-Mar-2242
anon@lowtide:~/code/dfsdates$ ./dupes 99
generated 100000 random time_t values to get 100000 days
day dupes: 7
sorted:
rannum[0]: -105146334440: 17-Jan--1362 (year is BC)
rannum[99999]: 105017655638: 15-Nov-5297
anon@lowtide:~/code/dfsdates$ ./dupes 999
generated 100000 random time_t values to get 100000 days
day dupes: 0
sorted:
rannum[0]: -1068460845381: 28-Oct--31889 (year is BC)
rannum[99999]: 1063842312377: 26-Oct-35681
anon@lowtide:~/code/dfsdates$
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Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-07 12:27 -0500
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-07 19:52 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-07 21:28 -0500
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-08 05:52 +0000
Re: Where are you, sdb? I have something fun for your little morons to try chrisv <chrisv@nospam.invalid> - 2016-12-08 07:02 -0600
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-08 09:02 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Adlbifhr Mjduhgfks <am@random.us> - 2016-12-08 00:32 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-07 21:48 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Adlbifhr Mjduhgfks <am@random.us> - 2016-12-08 14:17 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-08 11:00 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Steve Carroll <fretwizzer@gmail.com> - 2016-12-08 09:13 -0800
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-08 18:41 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Steve Carroll <fretwizzer@gmail.com> - 2016-12-08 17:32 -0800
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-08 21:12 -0500
Cartoons are easier to read than the Wall Street Journal. Jeff-Relf.Me <@.> - 2016-12-08 20:16 -0800
Re: Where are you, sdb? I have something fun for your little morons to try Steve Carroll <fretwizzer@gmail.com> - 2016-12-09 09:03 -0800
Re: Where are you, sdb? I have something fun for your little morons to try Adlbifhr Mjduhgfks <am@random.us> - 2016-12-08 15:49 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-08 11:00 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Adlbifhr Mjduhgfks <am@random.us> - 2016-12-08 16:24 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-08 18:43 -0500
Only _results_ matter; i.e.: What does it do ? Jeff-Relf.Me <@.> - 2016-12-08 19:45 -0800
Re: Only _results_ matter; i.e.: What does it do ? flatfish+++ <flatfish@linuxmail.org> - 2016-12-08 22:50 -0500
I don't need the source code. Jeff-Relf.Me <@.> - 2016-12-08 20:39 -0800
Re: I don't need the source code. flatfish+++ <flatfish@linuxmail.org> - 2016-12-08 23:48 -0500
I'm hard to copy, thank God. Jeff-Relf.Me <@.> - 2016-12-08 22:30 -0800
Re: I'm hard to copy, thank God. flatfish+++ <flatfish@linuxmail.org> - 2016-12-09 01:54 -0500
Re: I'm hard to copy, thank God. Steve Carroll <fretwizzer@gmail.com> - 2016-12-09 12:30 -0800
Re: I don't need the source code. Poutnik <poutnik4nntp@gmail.com> - 2016-12-09 07:12 +0100
Re: I don't need the source code. flatfish+++ <flatfish@linuxmail.org> - 2016-12-09 01:15 -0500
Re: I don't need the source code. Poutnik <poutnik4nntp@gmail.com> - 2016-12-09 07:27 +0100
Re: I don't need the source code. flatfish+++ <flatfish@linuxmail.org> - 2016-12-09 01:44 -0500
Usenet is not CraigsList nor WikiPedia, Reddit. Jeff-Relf.Me <@.> - 2016-12-08 23:00 -0800
Re: Usenet is not CraigsList nor WikiPedia, Reddit. flatfish+++ <flatfish@linuxmail.org> - 2016-12-09 02:12 -0500
If/When Cola is being honest, they don't think MicroSoft is "Evil". Jeff-Relf.Me <@.> - 2016-12-08 23:56 -0800
Re: Usenet is not CraigsList nor WikiPedia, Reddit. Poutnik <poutnik4nntp@gmail.com> - 2016-12-09 08:16 +0100
Usually, the __DEFAULT__ "Subject:" line isn't best. Jeff-Relf.Me <@.> - 2016-12-08 22:53 -0800
Re: Usually, the __DEFAULT__ "Subject:" line isn't best. Poutnik <poutnik4nntp@gmail.com> - 2016-12-09 08:19 +0100
Please lookup the word "Default". Jeff-Relf.Me <@.> - 2016-12-08 23:31 -0800
Re: Please lookup the word "Default". Poutnik <poutnik4nntp@gmail.com> - 2016-12-09 08:42 +0100
The parent post. -- Re: Please lookup the word "Default". Jeff-Relf.Me <@.> - 2016-12-09 00:12 -0800
Re: The parent post. -- Re: Please lookup the word "Default". Poutnik <poutnik4nntp@gmail.com> - 2016-12-09 11:28 +0100
Threads branch like a tree, SubTopics sprout. Jeff-Relf.Me <@.> - 2016-12-09 03:35 -0800
Re: Threads branch like a tree, SubTopics sprout. Poutnik <poutnik4nntp@gmail.com> - 2016-12-09 16:18 +0100
Re: The parent post. -- Re: Please lookup the word "Default". moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-12-09 15:05 +0000
I want details, Michael Moroney. Jeff-Relf.Me <@.> - 2016-12-09 07:18 -0800
Re: I want details, Michael Moroney. Steve Carroll <fretwizzer@gmail.com> - 2016-12-09 10:38 -0800
Re: I want details, Michael Moroney. moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-12-10 04:03 +0000
I never had to deal with such problems. Jeff-Relf.Me <@.> - 2016-12-09 21:15 -0800
Re: I never had to deal with such problems. moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-12-11 01:50 +0000
Re: The parent post. -- Re: Please lookup the word "Default". chrisv <chrisv@nospam.invalid> - 2016-12-09 09:37 -0600
Re: The parent post. -- Re: Please lookup the word "Default". moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-12-09 20:32 +0000
Re: I don't need the source code. chrisv <chrisv@nospam.invalid> - 2016-12-09 06:39 -0600
Re: I don't need the source code. Poutnik <poutnik4nntp@gmail.com> - 2016-12-09 16:19 +0100
Re: I don't need the source code. Silver Slimer <.m@nsn.s> - 2016-12-09 11:51 -0500
Re: I don't need the source code. flatfish+++ <flatfish@linuxmail.org> - 2016-12-09 12:07 -0500
Re: I don't need the source code. Silver Slimer <.m@nsn.s> - 2016-12-09 12:22 -0500
Re: I don't need the source code. flatfish+++ <flatfish@linuxmail.org> - 2016-12-09 12:28 -0500
Re: I don't need the source code. moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-12-09 17:52 +0000
I only have time to read a few select authors, sorry. Jeff-Relf.Me <@.> - 2016-12-09 10:05 -0800
Re: I don't need the source code. chrisv <chrisv@nospam.invalid> - 2016-12-09 12:26 -0600
Re: I don't need the source code. Silver Slimer <.m@nsn.s> - 2016-12-09 14:06 -0500
Re: I don't need the source code. Chris Ahlstrom <OFeem1987@teleworm.us> - 2016-12-09 19:56 -0500
Re: I don't need the source code. Silver Slimer <.m@nsn.s> - 2016-12-10 09:23 -0500
Re: Only _results_ matter; i.e.: What does it do ? fr314159@gmail.com - 2016-12-09 07:17 -0800
Re: Only _results_ matter; i.e.: What does it do ? DFS <nospam@dfs.com> - 2016-12-12 18:54 -0500
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-12 18:39 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <mel@zzzzz.com> - 2016-12-09 03:38 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-09 19:00 +0000
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <mel@zzzzz.com> - 2016-12-10 00:33 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-10 05:24 +0000
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <Melzzzzz@zzzzz.com> - 2016-12-10 06:54 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-10 06:25 +0000
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <Melzzzzz@zzzzz.com> - 2016-12-10 07:28 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-10 19:56 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 15:19 -0500
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 15:23 -0500
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-10 20:44 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 17:55 -0500
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-11 00:02 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 19:39 -0500
C/CPP's "srand( int Seed )" generates an array of (PseudoRandom) int's. Jeff-Relf.Me <@.> - 2016-12-10 23:09 -0800
Re: C/CPP's "srand( int Seed )" generates an array of (PseudoRandom) int's. deplorable owl <owl@rooftop.invalid> - 2016-12-11 07:23 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 19:56 -0500
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 20:07 -0500
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-11 04:07 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-11 00:18 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <mel@zzzzz.com> - 2016-12-11 03:40 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-11 04:00 +0000
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <Melzzzzz@zzzzz.com> - 2016-12-11 05:08 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-11 04:27 +0000
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <Melzzzzz@zzzzz.com> - 2016-12-11 05:58 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-11 05:55 +0000
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <Melzzzzz@zzzzz.com> - 2016-12-11 07:11 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-11 06:49 +0000
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <mel@zzzzz.com> - 2016-12-11 07:52 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-11 07:09 +0000
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <Melzzzzz@zzzzz.com> - 2016-12-11 08:23 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-11 07:37 +0000
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <Melzzzzz@zzzzz.com> - 2016-12-11 08:40 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-11 09:05 +0000
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-10 19:41 +0000
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <mel@zzzzz.com> - 2016-12-10 20:48 +0100
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-10 20:06 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 10:32 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Melzzzzz <mel@zzzzz.com> - 2016-12-10 16:40 +0100
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 11:03 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Steve Carroll <fretwizzer@gmail.com> - 2016-12-10 09:26 -0800
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 12:38 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Steve Carroll <fretwizzer@gmail.com> - 2016-12-10 09:52 -0800
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 13:01 -0500
Re: Where are you, sdb? I have something fun for your little morons to try Steve Carroll <fretwizzer@gmail.com> - 2016-12-10 10:06 -0800
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-10 19:38 +0000
Re: Where are you, sdb? I have something fun for your little morons to try DFS <nospam@dfs.com> - 2016-12-10 19:55 -0500
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-10 19:33 +0000
Re: Where are you, sdb? I have something fun for your little morons to try deplorable owl <owl@rooftop.invalid> - 2016-12-10 20:00 +0000
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