[R] generate random numbers that sum up to 1

[Peter Dalgaard]

"sun" <as at hut.at> writes:

> I am trying to generate a vector of random numbers with the constraint that 
> they have to sum up to one with uniform distribution.
> 
> eg. {0.1,0.7,0.2 }
> 
> any function to do this? Thanks.

Depending on what you mean by "uniform", this may be a solution

> x<-runif(3)
> x/sum(x)
[1] 0.1130642 0.4098608 0.4770750

What you can't have is the individual components uniform and
identically distributed because the sum of the means would be 1.5 and
equal to the mean of the sum which is 1...

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