[R] missing value where TRUE/FALSE needed

[David Croll]

Hello dear R people,


for my MSc thesis I need to program some functions, and some of them 
simply do not work. In the following example, I made sure both vectors 
have the same length (10), but R gives me the following error:

Error in if (vector1[i] == vector2[j]) { :
  missing value where TRUE/FALSE needed

I googled for possible solutions, but I did not find a good explanation 
for this...


The code:

test <- function() {
   
    vector1 <- sample(1:100,10)
    vector2 <- sample(1:100,10)
   
    for (i in vector1) {
       
        for (j in vector2) {
           
            if (vector1[i] == vector2[j]) {
               
                show(list(i,j))
               
                }
               
            }
       
        }
   
    }   


Regards, David