OpenEuphoria

Re: 32-bit random numbers

• Posted by Tommy Carlier <tommy.carlier at pandora.be> Jul 03, 2004
• 607 views

I'll have another go:

function rand32(atom n)
	atom r
	if n <= #3FFFFFFF then return rand(n)
	else
		r = rand(#100) - 1
		for i = 1 to 3 do
			r = r * #100 + rand(#100) - 1
		end for
		return remainder(r, n) + 1
	end if
end function

What does it do? It composes r out of 4 bytes, each byte is a random number
between 0 and 255 ( = "rand(#100)-1" ).
This makes r a random integer between 0 and #FFFFFFFF. The distribution should
be as uniform as rand (each byte is independent from the other bytes).
The "remainder(r, n) + 1" produces a random integer between 1 and n.

--
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