[R] Replace a for loop with a function

[Eik Vettorazzi]

Hi Iris,
maybe I misinterpret this, but I think in the end it all comes down to
sample(1:3,50,prob=c(0.5,0.15,0.35),replace=T))

cheers

Am 19.09.2011 17:16, schrieb Eekhout, I.:
> Hi all, 
> 
> I would like to replace the for loop in the code below with a function
> to improve the speed and to make the script more efficient. 
> The loop creates a vector of integers (x) with the probability of f for
> each integer.
> The length of f is variable, but sums to 1. 
> I tried to use a function with optional arguments which did not work.
> 
> Here is the code:
> 
> f <- data.matrix(c(0.5,0.15,0.35))
> u <- runif(50) 
> x <- data.matrix(rep(1, n)) 
> fc <- 0
> 	for(i in 1:length(f))	{
> 		fc <- fc + f[i]         
> 		cf <- ifelse(u>fc,1,0)
> 		x <- x + cf
> 	}
> x
> 
> Can anyone help me with this translation?
> Thanks in advance, 
> 
> Iris
> 
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Eik Vettorazzi
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