a silly question on index of a matrix
?which
> X <- matrix(2:10, nrow=3)
> which(X == 10, arr.ind=TRUE)
row col
[1,] 3 3
HTH,
simon.
At 11:52 AM 26/10/2005, you wrote:
Hi netters, This is probably a silly question,but I can't find the answer after searching the R-help archives online. ok, I have a matrix. I know there is a "10" somewhere in it. Now I want to know the index of the element "10" in this matrix. That is, if X[i,j]=10, I want to know i and j. Is there a R function to do this? Just like the "find" function in matlab. Thanks all!
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