[R] How to subtract the counter i in for loop?

[Berend Hasselman]

On 30-11-2012, at 07:18, C W wrote:

> thanks, Berend.  Both of your code works great.  Is there a function that can do it?  
> 
> Something like this:
> x <- matrix(NA, nrow=15, ncol=2)
> for(i in 1:15){
>    x[i,] <- sample(c(NA, 20, 77), 2, prob=c(0.2, 0.3, 0.4))
> }
> 
> > x
> 
>       [,1] [,2]
> 
>  [1,]   NA   77
> 
>  [2,]   77   NA
> 
>  [3,]   NA   77
> 
>  [4,]   77   20
> 
>  [5,]   77   20
> 
>  [6,]   77   20
> 
>  [7,]   20   NA
> 
>  [8,]   77   20
> 
>  [9,]   77   NA
> 
> [10,]   77   NA
> 
> [11,]   77   20
> 
> [12,]   20   77
> 
> [13,]   NA   77
> 
> [14,]   77   20
> 
> [15,]   77   20
> 
> I want to have a column of 15 samples without NA's.  Is there an R function like ifelse()?
> 

It's not clear what you exactly want.
A matrix with 15 rows and some columns?
How do you want to remove the NA's in each column?
Then why don't you leave out the NA in the sample?

Berend