> It will always be less precise, i.e. choosing among fewer numbers. No?

even if you don't want to use a self defined precission you could try this

perl -Mposix -E" say rand(1+1/2**47) for 1..20"

So why 47?

Just try and error on my system

C:\Windows\system32>perl -E" say 1+1/2**47;"                          
+         
1.00000000000001
C:\Windows\system32>perl -E" say 1+1/2**48;"
1

[download]

I'm too lazy to figure out how exactly the limits of the mantissa is used internally and where the caveats are.

And taking the rounding errors in these into assumption this shouldn't matter much. (as BUK mentioned under windows before 5.20 rand is limted to 15 bits only.)

The practical value of this is too small to justify more elaboration.

update

or alternatively to avoid floats and rounding errors

C:\Windows\system32>perl -E"$r=int rand(1e15+1); say $r==1e15 ? 1 : sp
+rintf '0.%015s', $r"

0.176483154296875

[download]

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Re^5: inclusive rand by LanX
in thread inclusive rand by msh210

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