FAQ Topic - How do I generate a random integer in [1..N]?

[FAQ server]

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FAQ Topic - How do I generate a random integer in [1..N]?
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function Random(x) { return Math.floor(x*Ma th.random()) }

gives a random number in the range 0..(x-1);
`` Random(N)+1 '' for [1..N]

http://msdn.microsoft.com/library/en...smthrandom.asp

http://docs.sun.com/source/816-6408-10/math.htm

How to Deal and Shuffle:

http://www.merlyn.demon.co.uk/js-randm.htm
===
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[Dr John Stockton]

JRS: In article <44************ ***********@new s.sunsite.dk>, dated Sun,
3 Sep 2006 23:00:02 remote, seen in news:comp.lang. javascript, FAQ
server <ja********@dot internet.bepost ed :

>-----------------------------------------------------------------------
FAQ Topic - How do I generate a random integer in [1..N]?
-----------------------------------------------------------------------

function Random(x) { return Math.floor(x*Ma th.random()) }

gives a random number in the range 0..(x-1);
`` Random(N)+1 '' for [1..N]

Identifier x should be renamed N or similar.

I'd change it to

FAQ Topic - How do I generate a random integer in [0..N-1]?

function Random(N) { return Math.floor(Math .random()*N) }

gives a random number in the range 0..(N-1);

// `` Random(N)+1 '' for [1..N]
That should be obvious. Omit?

--
© John Stockton, Surrey, UK. ?@merlyn.demon. co.uk Turnpike v4.00 MIME. ©
<URL:http://www.merlyn.demo n.co.uk/TP/BP/Delphi/&c., FAQqy topics & links;
<URL:http://www.merlyn.demo n.co.uk/clpb-faq.txt RAH Prins : c.l.p.b mFAQ;
<URL:ftp://garbo.uwasa.fi/pc/link/tsfaqp.zipTimo Salmi's Turbo Pascal FAQ.

[Evertjan.]

Dr John Stockton wrote on 04 sep 2006 in comp.lang.javas cript:

FAQ Topic - How do I generate a random integer in [0..N-1]?

function Random(N) { return Math.floor(Math .random()*N) }

gives a random number in the range 0..(N-1);

// `` Random(N)+1 '' for [1..N]
That should be obvious. Omit?

Omitting that would be an omission.

--
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)

[John G Harris]

In article <QQ************ **@merlyn.demon .co.uk>, Dr John Stockton
<jr*@merlyn.dem on.co.ukwrites

>JRS: In article <44************ ***********@new s.sunsite.dk>, dated Sun,
3 Sep 2006 23:00:02 remote, seen in news:comp.lang. javascript, FAQ
server <ja********@dot internet.bepost ed :

>>-----------------------------------------------------------------------
FAQ Topic - How do I generate a random integer in [1..N]?
-----------------------------------------------------------------------

function Random(x) { return Math.floor(x*Ma th.random()) }

gives a random number in the range 0..(x-1);
`` Random(N)+1 '' for [1..N]

Identifier x should be renamed N or similar.

n (lower case) would be even better.

>I'd change it to

FAQ Topic - How do I generate a random integer in [0..N-1]?

Now explain what the square brackets mean, and the Pascal ".." .

>function Random(N) { return Math.floor(Math .random()*N) }

gives a random number in the range 0..(N-1);

"0 to (n-1) inclusive"

// `` Random(N)+1 '' for [1..N]
That should be obvious. Omit?

John
--
John Harris