# Test for Equality of All Vector Elements in R

In this article, we will test the equality of all vector elements in R programming language.

**Method 1: Using variance**

We can say that all vector elements are equal if the variance is zero. We can find variance by using the var() function

**Syntax:**

var(vector)==0

where vector is an input vector

This function returns true if all elements are the same, otherwise false.

**Example: **R program to check all elements in a vector equality

## R

`# consider a vector with same elements` `vec1 = ` `c` `(7, 7, 7, 7, 7, 7, 7)` ` ` `print` `(` `var` `(vec1) == 0)` ` ` `# consider a vector with different elements` `vec2 = ` `c` `(17, 27, 37, 47, 57, 7, 7)` ` ` `print` `(` `var` `(vec2) == 0)` |

**Output:**

[1] TRUE [1] FALSE

**Method 2: Using ****length()**** and unique() function**

By using unique function if all the elements are the same then the length is 1 so by this way if the length is 1, we can say all elements in a vector are equal.

**Syntax:**

length(unique(vector))==1

- length() is used to find the length of unique vector
- unique() is used to get the unique values in a vector

If all elements are the same it returns true, otherwise false

**Example:** R program to test the equality of all elements in a vector

## R

`# consider a vector with same elements` `vec1 = ` `c` `(7, 7, 7, 7, 7, 7, 7)` ` ` `print` `(` `length` `(` `unique` `(vec1)) == 1)` ` ` `# consider a vector with different elements` `vec2 = ` `c` `(17, 27, 37, 47, 57, 7, 7)` ` ` `print` `(` `length` `(` `unique` `(vec2)) == 1)` |

**Output:**

[1] TRUE [1] FALSE