[R] Strange "Error: subscript out of bounds"

[Petri Lankoski]

Dear all,


I am trying to write a function for visualizing ordinal model results. 
The function works fine with some values, but then I get "Error: 
subscript out of bounds" even there the index should be pointing a legal 
item. Code is below as well as the example of failure:

plotProb <- function(pre.mat, parts, split, titles, xlab="") {
	par(mfrow = split)
	n <- 1
	for(k in parts) {
		print("debug")
		print(k)
		print(n)
		print(length(pre.mat))
		print(pred.mat[k,])
		print(titles[n])
		plot(1:5, pred.mat[k,], lty=2, type="l", ylim=c(0,1), xlab=xlab, 
axes=FALSE, ylab="Probability", las=1, main=titles[n])
		axis(1)
		axis(2)
		lines(1:5, pred.mat[k+1,], lty=1)
		lines(1:5, pred.mat[k+2,], lty=3)
		legend("topright", c("avg. player", "5th %-tile player", "95th %-tile 
player"), lty=1:3, bty="n")
		n<-n+1
	}
}

plotProb(q8.pred.mat.v13, c(193, 196, 199, 205, 217,241,289), c(3,3), 
q8.titles3, "identification")
[1] "debug"
[1] 193
[1] 1
[1] 1920
Error in print(pred.mat[k, ]) :
   error in evaluating the argument 'x' in selecting a method for 
function 'print': Error: subscript out of bounds
 > print(q8.pred.mat.v13[193,])
[1] 0.28478261 0.39674035 0.22653917 0.07992141 0.01201645

(However, a call, plotProb(q8.pred.mat.v13, c(1,4,7,13,25,49,97), 
c(3,3), q8.titles2, "identification"), seems to work ok.)


Any hints how to tackle this are appreciated.


-- 
Petri Lankoski, petri.lankoski at iki.fi
www.iki.fi/petri.lankoski