R: How to replace a character in a string after sampling and print out character instead of index?
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I'd like to replace a character in a string with another character, by first sampling by the character. I'm having trouble having it print out the character instead of the index. 

Example data, is labelled "try": 

    L	0.970223325	-	0.019851117	X	0.007444169
    K	0.962779156	-	0.027295285	Q	0.004962779
    P	0.972704715	-	0.027295285	NA	0
    C	0.970223325	-	0.027295285	L	0.00248139
    V	0.970223325	-	0.027295285	T	0.00248139

I'm trying to sample a character for a given row using weighted probabilities.
    
    samp <- function(row) {
    sample(try[row,seq(1, length(try), 2)], 1, prob = try[row,seq(2, length(try), 2)])
    }

Then, I want to use the selected character to replace a position in a given string.

    subchar <- function(string, pos, new) {
	paste(substr(string, 1, pos-1), new , substr(string, pos+1, nchar(string)), sep='')
    }

My question is - if I do, for example
    
    > subchar("KLMN", 3, samp(4))
    [1] "KL1N"

But I want it to read "KLCN". As.character(samp(4)) doesn't work either. How do I get it to print out the character instead of the index?