R - Sort dataframe with multiple columns

• An example to show how to sort (including descending order) dataframe with multiple column values.

 > data  # if we have data.frame (variable data here)
   b x y z  
 1 Hi A 8 1  
 2 Med D 3 1  
 3 Hi A 9 1  
 4 Low C 9 2    
 > data[order(data[,4]),]  # sort by 4th column, which is z here
   b x y z  
 1 Hi A 8 1  
 2 Med D 3 1  
 3 Hi A 9 1  
 4 Low C 9 2  
 > data[order(-data[,4]),]  # sort by 4th column, with descending order 
   b x y z  
 4 Low C 9 2  
 1 Hi A 8 1  
 2 Med D 3 1  
 3 Hi A 9 1  
 > data[order(-data[,4], data[,3]),]  # sort by 4th column(z), then sort by 3rd column(y)
   b x y z  
 4 Low C 9 2  
 2 Med D 3 1  
 1 Hi A 8 1  
 3 Hi A 9 1