Change row order in a matrix/dataframe

Question

I need to change/invert rows in my data frame, not transposing the data but moving the bottom row to the top and so on. If the data frame was:

1 2 3 
4 5 6
7         


        

Answer 1

Encounter this problem today and here I am providing another solution for your interests.

m <- matrix(1:9, ncol=3, byrow=TRUE)    
apply(m,2,rev)