How to prevent merge from reordering columns

Question

In the following example

x <- data.frame(code = 7:9, food = c(\'banana\', \'apple\', \'popcorn\'))
y <- data.frame(food = c(\'banana\', \'apple\', \'po         


        

Answer 1

plyr makes this easy:

 x <- data.frame(code = 7:9, food = c('banana', 'apple', 'popcorn'))
 y <- data.frame(food = c('banana', 'apple', 'popcorn'),
                isfruit = c('fruit', 'fruit', 'not fruit'))

library(plyr)
join(x,y)

        #GOOD 
#Joining by: food
#  code    food   isfruit
#1    7  banana     fruit
#2    8   apple     fruit
#3    9 popcorn not fruit

    #BAD  
# merge(x,y)
#     food code   isfruit
#1   apple    8     fruit
#2  banana    7     fruit
#3 popcorn    9 not fruit