r - Merge two tables with same id -


this question has answer here:

i have data frame this:

df1:     x1  x2   x3 1    1   4    7 2    2   5    8 3    3   6    9  class(df1[1,"x1"])

[1] "character"

now have data frame this:

df2:     id    name 1     1       2     2       c 3     3       b 4     4       z 5     5       x 6     6       g 7     7       e 8     8       y 9     9       h

the id here numeric

every character in df1 same number in df2. result need:

    x1  x2   x3 1      z    e 2    c   x    y 3    b   g    h

i know can merge 2 tables same key, in case, key on df1 data in table.

we can use match this

df1[] <-  lapply(df1, function(x) df2$name[match(x, df2$id)]) df1 #   x1 x2 x3 #1   z  e #2  c  x  y #3  b  g  h

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