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

Groups > comp.sys.acorn.programmer > #5775

Re: Specific numbers but in a random sequence

Show all headers | View raw

On 22/06/2019 16:46, Richard Ashbery wrote:
> In article <qel12p$ibq$1@dont-email.me>,
>     druck <news@druck.org.uk> wrote:
>> On 21/06/2019 22:27, Gavin Crawford wrote:
>>> Richard Ashbery <basura@invalid.addr.uk> Wrote in message:
> 
> [snip]
> 
> 3,4,5,6,8,9,10,12,15,18,20,24,30,36,45,60,90,120I would like to be
> able to use these variables in a random sequence.
> 
>>> Why not put them into an array and use a random number to choose
>>>    the array index.
> 
>> Yes, and make sure you seed the random number generator, or it may
>> always go through the same pseudo random sequence each time its run.
> 
>> IIRC to seed do RND(-TIME) before any other call to RND.
> 
> Not quite there yet - if I use the following...
> 
> DIM array%(18)
> array%() = 3,4,5,6,8,9,10,12,15,18,20,24,30,36,45,60,90,120
> y = RND(-TIME)
> FOR loop = 1 TO 5
> FOR I% = 0 TO 18
> PRINT array%(RND(I%))
> NEXT I%
> NEXT loop
> 
> 90 random numbers gives poor distribution:
> 
> 3 x10
> 4 x14
> 5 x16
> 6 x8
> 8 x9
> 9 x4
> 10 x6
> 12 x3
> 15 x2
> 18 x3
> 20 x7
> 24 x7
> 30 x2
> 36 none
> 45 none
> 60 x2
> 90 none
> 120 x1
> 
> 5 is repeated 3 times in a row.
> 
> Is there any way of improving it?
> 
Does it always give such a poor distribution,  even across multiple 
runs?    What about if you did RND(someBigNumber) MOD 18 ?

Back to comp.sys.acorn.programmer | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Specific numbers but in a random sequence Richard Ashbery <basura@invalid.addr.uk> - 2019-06-21 21:31 +0100
  Re:Specific numbers but in a random sequence Gavin Crawford <gc@dentrassis.com> - 2019-06-21 22:27 +0100
    Re: Specific numbers but in a random sequence druck <news@druck.org.uk> - 2019-06-22 11:48 +0100
      Re: Specific numbers but in a random sequence Richard Ashbery <basura@invalid.addr.uk> - 2019-06-22 12:03 +0100
      Re: Specific numbers but in a random sequence Richard Ashbery <basura@invalid.addr.uk> - 2019-06-22 16:46 +0100
        Re: Specific numbers but in a random sequence Someone Somewhere <nntpac@gmail.com> - 2019-06-22 17:11 +0100
          Re: Specific numbers but in a random sequence Richard Ashbery <basura@invalid.addr.uk> - 2019-06-22 18:21 +0100
            Re: Specific numbers but in a random sequence Steve Fryatt <news@stevefryatt.org.uk> - 2019-06-22 21:29 +0100
              Re: Specific numbers but in a random sequence Richard Ashbery <basura@invalid.addr.uk> - 2019-06-23 11:17 +0100
                Re: Specific numbers but in a random sequence Ian <Ian.Hamilton@AAUG.net> - 2019-06-23 12:07 +0100
                Re: Specific numbers but in a random sequence Paul Oates <oatespaul@btinternet.com> - 2019-06-23 13:17 +0100
                Re: Specific numbers but in a random sequence Steve Fryatt <news@stevefryatt.org.uk> - 2019-06-23 13:51 +0100
                Re: Specific numbers but in a random sequence Richard Ashbery <basura@invalid.addr.uk> - 2019-06-23 14:10 +0100
                Re: Specific numbers but in a random sequence Steve Fryatt <news@stevefryatt.org.uk> - 2019-06-23 15:59 +0100
                Re: Specific numbers but in a random sequence Richard Ashbery <basura@invalid.addr.uk> - 2019-06-23 17:14 +0100
                Re: Specific numbers but in a random sequence Richard Ashbery <basura@invalid.addr.uk> - 2019-06-23 14:01 +0100
        Re: Specific numbers but in a random sequence Paul Oates <oatespaul@btinternet.com> - 2019-06-22 17:52 +0100
        Re: Specific numbers but in a random sequence Julian Fry <julianfry@orpheusmail.co.uk> - 2019-06-22 17:56 +0100
        Re: Specific numbers but in a random sequence Julian Fry <JulianFry@compuserve.com> - 2019-06-22 18:05 +0100
  Re: Specific numbers but in a random sequence Sebastian Barthel <naitsabes@freenet.de> - 2019-06-24 07:37 +0000
    Re: Specific numbers but in a random sequence Richard Ashbery <basura@invalid.addr.uk> - 2019-06-24 20:13 +0100

csiph-web