cbind two different column lengths

[z.ageru]

the first dataframe contains duplicate values of a single observation which the column length is long, while the second dataframe contains identifiers or unique values which column lengh is shorter than the first data frame. so how we can combine or merge the two dataframes?
thank you in advance!!

[siddharthprabhu]

You could use a join(). Here's an example.

library(dplyr, warn.conflicts = FALSE)

long_df <- data.frame(id = c("A", "A", "B", "A", "B"), 
                      value = c(30L, 10L, 5L, 20L, 15L))

short_df <- data.frame(id = c("A", "B"),
                       cat = c("Apple", "Banana"))

long_df %>% left_join(short_df, by = "id")
#>   id value    cat
#> 1  A    30  Apple
#> 2  A    10  Apple
#> 3  B     5 Banana
#> 4  A    20  Apple
#> 5  B    15 Banana

^{Created on 2020-04-27 by the reprex package (v0.3.0)}

[z.ageru]

thank you very much i satisfied by the answer