Invoices: These are a type of data object in the R programming language that are used to classify data and store it as a surface. These factors can store both strings and integers.
R programming language, They are useful for columns that have a limited number of specific values. Such as “Male”, “Female”, True, False, etc. They are useful in data analysis for statistical modeling.
Example
# Create a vector as input.
data <- c (“East”, “West”, “East”, “North”, “North”, “East”, “West”, “West”, “West”, “East”, “North”)
print (data)
print (is.factor (data))
# Apply the factor function.
factor_data <- factor (data)
print (factor_data)
print (is.factor (factor_data))
When we run the above code; The following result is obtained:
[1] “East” “West” “East” “North” “North” “East” “West” “West” “West” “East” “North”
[1] FALSE
[1] East West East North North East East West West West East
Levels: East North West
[1] TRUE
Invoices in the data frame
In creating any data frame with a column of textual data, R treats the textual column as an absolute data and generates factors on it:
# Create the vectors for data frame.
height <- c (132,151,162,139,166,147,122)
weight <- c (48,49,66,53,67,52,40)
gender <- c (“male”, “male”, “female”, “female”, “male”, “female”, “male”)
# Create the data frame.
input_data <- data.frame (height, weight, gender)
print (input_data)
# Test if the gender column is a factor.
print (is.factor (input_data $ gender))
# Print the gender column so see the levels.
print (input_data $ gender)
When we run the above code; The following results are obtained:
height weight gender
1 132 48 male
2 151 49 male
3 162 66 female
4 139 53 female
5 166 67 male
6 147 52 female
7 122 40 male
[1] TRUE
[1] male male female female male female male
Levels: female male
Change the order of the levels
The order of the levels in an invoice can be determined by re-applying the invoice function to a new order of levels; Changed.
data <- c (“East”, “West”, “East”, “North”, “North”, “East”, “West”,
“West”, “West”, “East”, “North”)
# Create the factors
factor_data <- factor (data)
print (factor_data)
# Apply the factor function with required order of the level.
new_order_data <- factor (factor_data, levels = c (“East”, “West”, “North”))
print (new_order_data)
data <- c (“East”, “West”, “East”, “North”, “North”, “East”, “West”,
“West”, “West”, “East”, “North”)
# Create the factors
factor_data <- factor (data)
print (factor_data)
# Apply the factor function with required order of the level.
new_order_data <- factor (factor_data, levels = c (“East”, “West”, “North”))
print (new_order_data)
When we run the above code; The following result is obtained:
[1] East West East North North East East West West West East
Levels: East North West
[1] East West East North North East East West West West East
Levels: East West North
Generate levels in one invoice
We can create invoice levels using the gl () function . This function takes two integers as input, which represent the number of levels and the number of repetitions of each level.
Syntax
gl (n, k, labels)
The parameters used in the above code are:
- n is an integer that indicates the number of levels.
- k is an integer that indicates the number of repetitions.
- lables is the removal of labels for invoice levels.
Example
v <- gl (3, 4, labels = c (“Tampa”, “Seattle”, “Boston”))
print (v)
When we run the above code; We get the following result:
Tampa Tampa Tampa Tampa Seattle Seattle Seattle Seattle Seattle Boston
[10] Boston Boston Boston
Levels: Tampa Seattle Boston