Here we are explaining how to write an R program to change the first level of a factor with another level of a given factor. Here we are using built-in functions **levels(),factor()** for this conversion. The vector values are passed to these functions directly here. The **levels(), factor()** functions in R computes the levels of factors of the vector in a single function.

Using the function **factor() **we can create a factor of the vector and by using the **level()** function we can find levels of a factor. Factors are stored as integer vectors and which is closely related to vectors. The syntax of these functions are

```
```**levels(x)** #where x is an object, for example, a factor
**factor(x = character(), levels, labels = levels,exclude = NA, ordered = is.ordered(x), nmax = NA)**
#Where x is a vector of data, usually taking a small number of distinct values

Below are the steps used in the R program to find the levels of a factor of a given vector. In this R program, we directly give the values to built-in functions. And print the function result. Here we used variable **A** for assigning vector values variable** fa **for finding the factor value of the vector

**STEP 1**: Assign variable **A** with vector values

**STEP 2**: First print original vector values

**STEP 3**:Call the built-in function factor as **fa = factor(A)**

**STEP 4**: Print the factor of the vector

**STEP 6**:Call the built-in function levels as **levels(fa)[1] = "e"**

**STEP 7**: print the variable **fa**

` ````
A= c("a", "b", "a", "c", "b")
print("Original vector is:")
print(A)
fa = factor(A)
print("Factor of the vector is:")
print(fa)
levels(fa)[1] = "e"
print(fa)
```

[1] "Original vector is:" [1] "a" "b" "a" "c" "b" [1] "Factor of the vector is:" [1] a b a c b Levels: a b c [1] e b e c b Levels: e b c