Message-ID: <4885A545-1CD1-4A8C-B69E-4CE42D86332C@utoronto.ca>
Date: 2014-11-22T15:29:18Z
From: Boris Steipe
Subject: Generate random numbers under constrain
In-Reply-To: <DUB125-W5735070367D5D71AE1EB02B3740@phx.gbl>
These are contradictory requirements: either you have n random numbers from the interval [0,1), then you can't guarantee anything about their sum except that it will be in [0,n). Or you constrain the sum, then your random numbers cannot be random in [0,1). You could possibly scale the random numbers:
n <- 13
x <- runif(n)
x <- x / sum(x)
x; sum(x)
This will guarantee that their sum is 1 (to numerical accuracy), but your numbers are then effectively drawn from the interval [0,2/n) for large n.
B.
On Nov 22, 2014, at 9:29 AM, Ragia Ibrahim <ragia11 at hotmail.com> wrote:
>
> Dear all,
> I use R 3.1.1 for Windows.
> kindly how can I generate n number of random numbers with probability from [0,1]
> and their sum must not be more than one
> thanks in advance
> Ragia
>
>
>
> [[alternative HTML version deleted]]
>
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