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Re: [ns] Generating random values having the probability density function



You could check the class RandomVariable to get an idea of how one can generate 
random numbers. You could also look at traffic generators (expoo, pareto).


>From: "Kejvan Redjamand (ERV)" <[email protected]>
>To: [email protected]
>Subject: [ns] Generating random values having the probability density function
>Date: Wed, 11 Oct 2000 16:08:14 +0200
>MIME-Version: 1.0
>
>Hi
>I'm a student doing my  Master Thesis. I need to implement a  function which
>calculates (actually generates random value of I/S values given its
>probability density function, f(x). How should the algorithm look like?
>Can any one help me with checking my thoughts below?
> I/S-values which is continuously distributed: f(x). It depends On N, number
>of users in our system which can take discrete values. We must know the
>typical values for I/S (we call it stochastic variable 'u'). 
> f(x) means actually P(u=x), where x is an actual concrete value from the
>values which the stochastic var u can take. 
>Then by assuming N form MIN to MAX (e.g.-1000) we can calculate 
>	1. probabilities f1, f2,... fmax and store them in an array: P.
>	2. I/S values (i.e. concrete u's- u1..umax  corresponding to
>probabilities) and store them in array U.
>The first question is which u's can we take? (Note that u is takes continuos
>values)
>Then second question is that we need to use random I/S- values from (U), but
>according to their probabilities from P; How can it be done?
>The main question is: Is the whole idea reasonable?
>
>regards
>
>// Kejvan
>Chalmers University of Technology, Sweden
>	

Tarik Alj

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