A user has the following matrix but wants to select the column which has a value of 11.how to do that?
one two three four
[1,] 1 6 11 16
[2,] 2 7 12 17
[3,] 3 8 11 18
[4,] 4 9 11 19
[5,] 5 10 15 20
Now to extract submatrix having column ‘three’ of value 11 we can do the following
m[m[, "three"] == 11,]
one two three four
[1,] 1 6 11 16
[3,] 3 8 11 18
[4,] 4 9 11 19