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