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Re: calculating pi [Re: php and big data and predictive modelling...]

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On Saturday, December 28, 2019 at 10:52:33 AM UTC+2, Luuk wrote:
> On 26-12-2019 23:18, Azathoth Hastur wrote:
> > On Sunday, December 22, 2019 at 5:43:09 AM UTC-5, robamm...@gmail.com wrote:
> >> pühapäev, 29. september 2019 18:41.47 UTC+3 kirjutas azathot...@gmail.com:
> >>> Anyone doing php psotgresql for this?
> >>>
> >>> The java framework craziness I see at work must have better alternatives!
> >>
> >> I have used postgresql and php. And doing some statistical calculations in php. For example I have tried to calculate Pi. I used the so called "bombing"(method with random numbers). But the result came out so that the first 4 numbers of the number were only correct. 3.141 . I ran the code about 50 times, and there were no differences in the about 3-4 first numbers. Maybe the "bombing" method is not very good for this. I got the idea of it from schools programming lesson. I'm sure other mathematical methods would be better, but it was intresting for me to program and test it.
> >>
> >> Basically I think, if you can program, then there is no difference in which language you program.
> >>
> >> With the best wishes,
> >> Kristjan Robam
> > 
> > Why not use the postgresql to calculate and sort, and php to just get in put and output?
> > 
> 
> Ok, its not postgresql, i tried to do 'calculate pi' in MSSQL 2017:
> 
> WITH pi (x, f, a, kwartpi) as
>    (SELECT 1,1.0,1,
>        CONVERT(float(53), 0.0)
>    UNION ALL
>    SELECT x+2,-f,x,
>        CONVERT(float(53),kwartpi+(f/x)) from pi where x<20000 and x>=a
>    )
> 
> SELECT top 10
>    x, 4*kwartpi
> FROM pi
> order by x desc
> OPTION(MAXRECURSION 10000)
> 
> 
> Output:
> x
> ----------- ----------------------
> 20001       3,14149265341197
> 19999       3,14169266341197
> 19997       3,14149263340797
> 19995       3,14169268341997
> 19993       3,14149261339597
> 19991       3,14169270343597
> 19989       3,14149259337597
> 19987       3,14169272345997
> 19985       3,14149257334797
> 19983       3,14169274349197
> 
> (10 rows affected)
> 
> 
> Completion time: 2019-12-28T09:49:58.2239611+01:00
> 
> *Will postgresql be better in doing this job?*
> 
> 
> Follow-up set to comp.databases.postgresql
> -- 
> Luuk

What is the idea of this ?
I used a circle inside a square and Pi=(Circle area)*4/(Square area)
And by the way the First numbers of pi area 3.14159.
My algorithm: https://groups.google.com/forum/#!topic/eesti-programmeerijad/qieWYzn8RxI


With the best wishes,
Kristjan Robam

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Re: calculating pi [Re: php and big data and predictive modelling...] robamman2019@gmail.com - 2019-12-28 02:22 -0800
  Re: calculating pi [Re: php and big data and predictive modelling...] robamman2019@gmail.com - 2019-12-28 04:55 -0800
    Re: calculating pi [Re: php and big data and predictive modelling...] robamman2019@gmail.com - 2019-12-28 08:30 -0800
    Re: calculating pi [Re: php and big data and predictive modelling...] robamman2019@gmail.com - 2019-12-28 09:40 -0800
      Re: calculating pi [Re: php and big data and predictive modelling...] robamman2019@gmail.com - 2019-12-29 04:15 -0800

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