Convert string from Lowercase to Uppercase - toupper() function in R

The toupper() function in R is utilized to convert strings from lowercase to uppercase. Here's a concise tutorial on how to use the toupper() function:

1. Basic Usage:

Convert a simple string to uppercase:

str1 <- "hello world"
str1_upper <- toupper(str1)
print(str1_upper)  # "HELLO WORLD"

2. Using with Character Vectors:

toupper() can be applied to character vectors, and it will operate element-wise:

fruits <- c("apple", "banana", "cherry")
fruits_upper <- toupper(fruits)
print(fruits_upper)  # "APPLE" "BANANA" "CHERRY"

3. Mixed Case Strings:

If a string has mixed case (both uppercase and lowercase letters), toupper() will convert only the lowercase letters:

mixed_str <- "HeLLo WoRlD"
mixed_upper <- toupper(mixed_str)
print(mixed_upper)  # "HELLO WORLD"

4. Non-Alphabetic Characters:

For characters that don't have a case (like numbers, punctuation, etc.), toupper() will not modify them:

special_str <- "Hello123! World."
special_upper <- toupper(special_str)
print(special_upper)  # "HELLO123! WORLD."

5. Using with Factors:

If you try to apply toupper() directly to a factor, you might encounter unexpected behavior since it's not designed for factors. To safely convert factor levels to uppercase:

Convert the factor to character.
Apply toupper().
Convert back to a factor (if desired).

fact <- factor(c("apple", "banana", "cherry"))
fact_upper <- factor(toupper(as.character(fact)))
print(fact_upper)

Key Takeaways:

toupper() is a straightforward and essential function in R for converting strings to uppercase.
The function can be applied to both individual strings and character vectors.
Always be cautious when working with factors. Convert them to character vectors first before applying toupper().

With this tutorial, you should be equipped to confidently convert strings from lowercase to uppercase in R using the toupper() function.

Convert string to uppercase in R:

# Create a character string
lowercase_string <- "hello, world!"

# Convert string to uppercase using toupper()
uppercase_string <- toupper(lowercase_string)

How to change case in R using toupper():

# Create a character vector
mixed_case_vector <- c("apple", "Banana", "Cherry")

# Change case to uppercase using toupper()
uppercase_vector <- toupper(mixed_case_vector)

String manipulation in R toupper():

# Create a character string
mixed_case_string <- "mIxEdCaSe"

# Perform uppercase conversion using toupper()
uppercase_result <- toupper(mixed_case_string)

R convert all letters to uppercase:

# Create a character string
mixed_case_string <- "convert me to uppercase"

# Convert all letters to uppercase using toupper()
all_uppercase_result <- toupper(mixed_case_string)

toupper() function in R with strings:

# Create a character string
lowercase_string <- "transform me to uppercase"

# Apply toupper() function to convert to uppercase
uppercase_result <- toupper(lowercase_string)

R programming change case of characters:

# Create a character vector
mixed_case_vector <- c("change", "CASE", "oF", "characters")

# Change case to uppercase using toupper()
uppercase_result <- toupper(mixed_case_vector)

Uppercase conversion in R with toupper():

# Create a character vector
lowercase_vector <- c("one", "two", "three")

# Perform uppercase conversion using toupper()
uppercase_result <- toupper(lowercase_vector)

R toupper() vs tolower() function:

# Create a character string
mixed_case_string <- "MiXeDcAsE"

# Compare toupper() and tolower() functions
uppercase_result <- toupper(mixed_case_string)
lowercase_result <- tolower(mixed_case_string)