Related Articles

# Merge Two Data Frames by common Columns in R Programming – merge() Function

• Last Updated : 12 Jun, 2020

`merge()` function in R Language is used to merge two data frames by common columns.

Syntax: merge(arg1, arg2, by.x, by.y)

Parameters:
arg1 and arg2: Data frames to be merged
by.x: Common argument of first data frame
by.y: Common argument of second data frame

Example 1:

 `# R program to merge two data frames`` ` `# Creating data frames``df1 <``-` `data.frame(row1 ``=` `c(``"a"``, ``"b"``, ``"c"``), row2 ``=` `c(``"d"``, ``"e"``, ``"f"``))``df2 <``-` `data.frame(col1 ``=` `c(``"a"``, ``"b"``, ``"c"``), col2 ``=` `c(``"Hello"``, ``"Geeks"``, ``"gfg"``))`` ` `# Calling merge() function``df <``-` `merge(df1, df2, by.x ``=``"row1"``, by.y ``=``"col1"``)``print``(df)`

Output:

```  row1 row2  col2
1    a    d Hello
2    b    e Geeks
3    c    f   gfg
```

Example 2:

 `# R program to merge two data frames`` ` `# Creating data frames``df1 <``-` `data.frame(row1 ``=` `c(``"d"``, ``"e"``, ``"f"``), row2 ``=` `c(``1``, ``2``, ``3``))``df2 <``-` `data.frame(col1 ``=` `c(``1``, ``2``, ``3``), col2 ``=` `c(``"Hello"``, ``"Geeks"``, ``"gfg"``))`` ` `# Calling merge() function``df <``-` `merge(df1, df2, by.x ``=``"row2"``, by.y ``=``"col1"``)``print``(df)`

Output:

```  row2 row1  col2
1    1    d Hello
2    2    e Geeks
3    3    f   gfg
```

My Personal Notes arrow_drop_up