**union() **function in R Language is used to combine the data of two objects. This function takes two objects like Vectors, dataframes, etc. as arguments and results in a third object with the combination of the data of both the objects.

Syntax:union(x, y)

Parameters:

x and y: Objects with sequence of items

**Example 1: Union of two Vectors**

`# R program to illustrate ` `# union of two vectors ` ` ` `# Vector 1 ` `x1 <` `-` `c(` `1` `, ` `2` `, ` `3` `, ` `4` `, ` `5` `, ` `6` `, ` `5` `, ` `5` `) ` ` ` `# Vector 2 ` `x2 <` `-` `c(` `8` `, ` `9` `) ` ` ` `# Union of two vectors ` `x3 <` `-` `union(x1, x2) ` ` ` `print` `(x3) ` |

*chevron_right*

*filter_none*

**Output:**

[1] 1 2 3 4 5 6 8 9

Here in the above code, the vector x1 contains values from 1-6, and x2 has two values. Now the union of these two vector x1 and x2 will combine each of the values present in them just once.

Note:Union of two vectors removes the duplicate elements in the final vector.

**Example 2: Union of two dataframes**

`# R program to illustrate ` `# the union of two data frames ` ` ` `# Data frame 1 ` `data_x <` `-` `data.frame(x1 ` `=` `c(` `5` `, ` `6` `, ` `7` `), ` ` ` `x2 ` `=` `c(` `1` `, ` `1` `, ` `1` `)) ` ` ` `# Data frame 2 ` `data_y <` `-` `data.frame(y1 ` `=` `c(` `2` `, ` `3` `, ` `4` `), ` ` ` `y2 ` `=` `c(` `2` `, ` `2` `, ` `2` `)) ` ` ` `# R union two data frames ` `data_z <` `-` `union(data_x, data_y) ` ` ` `print` `(data_z) ` |

*chevron_right*

*filter_none*

**Output:**

[[1]] [1] 5 6 7 [[2]] [1] 1 1 1 [[3]] [1] 2 3 4 [[4]] [1] 2 2 2

Here in the above code, we have created two data frames first with x1, x2 and second have y1, y2. Union of these two data frames creates a third data frame with combined values.