match two data.frames based on multiple columns

Question

My head stands still at the moment. I would like to match/extract data from a larger data.frame (df) based on the columns in a smaller data.frame (mdf). What I\'m getting st

Answer 1

Another way would be:

library(dplyr)
inner_join(df, mdf)

#Joining by: c("car_1", "car_2")
#              car_1          car_2  mpg cyl disp
#1        Datsun 710 Ford Pantera L 22.8   4  108
#2    Hornet 4 Drive   Ferrari Dino 21.4   6  258
#3 Hornet Sportabout  Maserati Bora 18.7   8  360
#4           Valiant     Volvo 142E 18.1   6  225