sorting - Keep observations only overlapped id in two data sets in R? -

i have 2 data sets. suppose data , data b , 2 data sets have id variables. in 2 data sets, want remove ids not overlapped. in other words, want keep ids exist in 2 data sets.

it depends on whether want separately each data set or if merge both data sets 1 data set (or data frame). can try dplyr.

library(dplyr) df1 <- data.frame(id = c("a", "b", "c"),                   var1 = c(1,2,3)) df2 <- data.frame(id = c("a", "c", "e"),                   var2 = c(4,5,6))  # matching ids in data frame 1 dplyr::semi_join(df1, df2, "id")  >   id var1 > 1     1 > 2  c    3  # matching ids in data frame 2 dplyr::semi_join(df2, df1, "id")  >   id var1 > 1     4 > 2  c    5  # merge column both data frames # matching id dplyr::inner_join(df1, df2, "id")  >   id var1 var2 > 1     1    4 > 2  c    3    5