Re^3: rand() function on Windows systems (pure Perl)

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Re^4: rand() function on Windows systems (pure Perl) by BillKSmith (Monsignor) on Dec 31, 2016 at 05:03 UTC
Thanks, BrowserUK. I have a low priority project which has been on hold for several years awaiting a solution to the problem described by the OP. Somehow, I overlooked the possibility of writing a generator. (The quality of the sequence is not an issue.) Your solution seems perfect! Bill	[reply]
Re^4: rand() function on Windows systems (pure Perl) by bakiperl (Beadle) on Dec 30, 2016 at 23:23 UTC
Wow! This is even better. Thank you.	[reply]
Re^5: rand() function on Windows systems (pure Perl)(Correction) by BrowserUk (Patriarch) on Jan 01, 2017 at 19:12 UTC
Hm. I forgot that Perl would upgrade the seed to a float; that needs to be clamped back to a 32-bit integer as the new line below: `{ my $seed; sub ppSrand{ $seed = int( $_[ 0 ] & 32767 ); } sub ppRand{ my $max = shift // 1; $seed = ( $seed * 214013 + 2531011 ); $seed &= 0xffffffff; return ( ( $seed >> 16 ) & 32767 ) / 32768 * $max; } }` [download] With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". The enemy of (IT) success is complexity. In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]
Re^6: rand() function on Windows systems (pure Perl)(Correction) by bakiperl (Beadle) on Jan 01, 2017 at 23:09 UTC
Great job man! This last fix cleared all my problems. Thank you again.	[reply]
Re^4: rand() function on Windows systems (pure Perl) by stevieb (Canon) on Dec 31, 2016 at 00:08 UTC
That's very nice. I'm glad we have statistical analysts/mathematicians here.	[reply]
Re^5: rand() function on Windows systems (pure Perl) by bakiperl (Beadle) on Dec 31, 2016 at 02:59 UTC
Small correction in the code above: This line of code : `return ( ( $seed >> 16 ) & 32767 ) / 32767 * $max;` [download] should be: `return ( ( $seed >> 16 ) & 32767 ) / 32768 * $max;` [download] The difference can be seen if you don't use the integer (int) function.	[reply] [d/l] [select]
Re^6: rand() function on Windows systems (pure Perl) by BrowserUk (Patriarch) on Dec 31, 2016 at 03:10 UTC
The difference can be seen if you don't use the integer (int) function. You are absolutely correct++! With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". The enemy of (IT) success is complexity. In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]
Re^7: rand() function on Windows systems (pure Perl) by bakiperl (Beadle) on Dec 31, 2016 at 16:10 UTC
Re^8: rand() function on Windows systems (pure Perl) by BrowserUk (Patriarch) on Dec 31, 2016 at 22:55 UTC
Re^8: rand() function on Windows systems (pure Perl) by BrowserUk (Patriarch) on Dec 31, 2016 at 20:18 UTC
Some notes below your chosen depth have not been shown here
Re^5: rand() function on Windows systems (pure Perl) by BrowserUk (Patriarch) on Dec 31, 2016 at 01:15 UTC
I'm glad we have statistical analysts/mathematicians here. He he. I am abysmal at statistics -- it is the second most unintuitive subject on the planet -- and I am to a mathematician, what a draughtsman is to an artist. I did a search and found this, the conversion to Perl was trivial :) With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". The enemy of (IT) success is complexity. In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]


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