I am trying to remove duplicated rows by one column (e.g the 1st column) in an R matrix. How can I extract the unique set by one column from a matrix? I've used
x_1 <- x[unique(x[,1]),]
While the size is correct, all of the values are NA. So instead, I tried
x_1 <- x[-duplicated(x[,1]),]
But the dimensions were incorrect.