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Re: [ns] Random Number Generator
On Wed, 25 Jul 2001, Sungwon Yi wrote:
> I am trying to generate random number to use it
> as traffic starting time between 30 to 40 sec.
> I used following ...
>
> set rng [new RNG]
> $rng seed 0
> $rng uniform 30.0 40.0
>
> $ns at $rng "$cbr0 start"
>
> However, It not seems to work. The traffic seems to
> be generated earlier than 30.0., and Please let me
> know if there is a way that I can check this value.
>
By default, there's a RNG created with every NS simulation. It's called
defaultRNG. So, here's what I think you want:
global defaultRNG
$defaultRNG seed 0
set unif [new RandomVariable/Uniform]
$unif set min_ 30.0
$unif set max_ 40.0
$ns at [$unif value] "$cbr0 start"
Michele
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Michele C. Weigle [email protected],
CB# 3175, Sitterson Hall [email protected]
Department of Computer Science http://www.cs.unc.edu/~clark
University of North Carolina Sitterson 327
Chapel Hill, NC 27599-3175 (919) 962-1909
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