Finding the column with the maximum value by row
apply(a, 1, which.max) Apply the which.max() function to the matrix a row-wise (1) Michael On Tue, Jul 17, 2012 at 5:03 PM, Christopher Desjardins
<cddesjardins at gmail.com> wrote:
Hi, Let's say I have the following data:
a=matrix(c(1,2,4,4,2,1,1,2,4),nrow=3,byrow=T)
a
[,1] [,2] [,3]
[1,] 1 2 4
[2,] 4 2 1
[3,] 1 2 4
What syntax should I use to get R to tell me the column that corresponds to
the maximum value for each row?
For my example, I would like to get a vector that says 3, 1, 3 because the
maximum value for row 1 is in column 3, the maximum value for row 2 is in
column 1, and the maximum value for row 3 is in column 3.
Does that make sense?
Please cc me if you reply!
Chris
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