strs: String Manipulation Functions in R

Overview

strs is an R package that provides a comprehensive set of string manipulation functions, mirroring the functionality and naming conventions of Python’s str methods. It aims to make string operations in R more accessible for users familiar with Python. Under the hood, every function uses the stringi package to ensure the results are consistent.

Installation

You can install the strs package directly from GitHub.

# Install devtools if you haven't already
install.packages("devtools")

# Install strs package from GitHub
devtools::install_github("pythonicr/strs")

Getting Started

Basic Usage

Here are some examples demonstrating how to use the functions provided by the strs package.

Capitalize the First Character of Each Sentence

The strs_capitalize function capitalizes the first character of each string in a character vector.

library(strs)

# Capitalize the first character of each sentence
capitalized <- strs_capitalize("hello world")
print(capitalized)
#> [1] "Hello world"

Perform Case Folding on Strings

The strs_casefold function performs case folding on each element of a character vector, useful for case-insensitive matching.

# Perform case folding
folded <- strs_casefold("HELLO World")
print(folded)
#> [1] "hello world"

Center a String in a Field of a Given Width

The strs_center function centers each element of a character vector in a field of a specified width, padding with a specified character.

# Center a string with padding
centered <- strs_center("hello", 10)
print(centered)
#> [1] "  hello   "

Check if String Contains a Substring

The strs_contains function checks whether each element of a character vector contains a specified substring.

# Check if strings contain a substring
contains <- strs_contains("hello world", "world")
print(contains)
#> [1] TRUE

Count Occurrences of a Substring in a String

The strs_count function counts the number of times a specified substring occurs in each element of a character vector.

# Count occurrences of a substring
count <- strs_count("hello world", "o")
print(count)
#> [1] 2

Check if String Ends With a Specified Suffix

The strs_endswith function determines whether each element of a character vector ends with a specified suffix.

# Check if strings end with a suffix
endswith <- strs_endswith("hello world", "world")
print(endswith)
#> [1] TRUE

Expand Tabs in a String to Spaces

The strs_expandtabs function replaces each tab character (\t) in a string with a specified number of spaces.

# Expand tabs to spaces
expanded <- strs_expandtabs("hello\tworld", 4)
print(expanded)
#> [1] "hello    world"

Find the First Occurrence of a Substring in a String

The strs_find function locates the first occurrence of a specified substring within each element of a character vector.

# Find the first occurrence of a substring
first_occurrence <- strs_find("hello world", "world")
print(first_occurrence)
#> [1] 7

Check if String is Alphanumeric

The strs_isalnum function checks whether each element of a character vector is alphanumeric.

# Check if strings are alphanumeric
isalnum <- strs_isalnum("hello123")
print(isalnum)
#> [1] TRUE

Check if String Contains Only Alphabetical Characters

The strs_isalpha function checks whether each element of a character vector contains only alphabetical characters.

# Check if strings are alphabetical
isalpha <- strs_isalpha("hello")
print(isalpha)
#> [1] TRUE

Check if String Contains Only ASCII Characters

The strs_isascii function determines whether each element of a character vector contains only ASCII characters.

# Check if strings are ASCII
isascii <- strs_isascii("hello")
print(isascii)
#> [1] TRUE

Check if String Contains Only Decimal Characters

The strs_isdecimal function checks whether each element of a character vector contains only decimal characters.

# Check if strings are decimal
isdecimal <- strs_isdecimal("12345")
print(isdecimal)
#> [1] TRUE

Check if String Contains Only Digits

The strs_isdigit function checks whether each element of a character vector contains only digits.

# Check if strings are digits
isdigit <- strs_isdigit("12345")
print(isdigit)
#> [1] TRUE

Check if String is in Lowercase

The strs_islower function checks whether each element of a character vector is in lowercase.

# Check if strings are lowercase
islower <- strs_islower("hello")
print(islower)
#> [1] TRUE

Check if String Contains Only Numeric Characters

The strs_isnumeric function checks whether each element of a character vector contains only numeric characters.

# Check if strings are numeric
isnumeric <- strs_isnumeric("12345")
print(isnumeric)
#> [1] TRUE

Check if String Contains Only Whitespace Characters

The strs_isspace function checks whether each element of a character vector contains only whitespace characters.

# Check if strings are whitespace
isspace <- strs_isspace("    ")
print(isspace)
#> [1] TRUE

Check if String is in Title Case

The strs_istitle function checks whether each element of a character vector is title case.

# Check if strings are title case
istitle <- strs_istitle("This Is Title Case")
print(istitle)
#> [1] TRUE

Check if String is in Uppercase

The strs_isupper function checks whether each element of a character vector is in uppercase.

# Check if strings are uppercase
isupper <- strs_isupper("HELLO")
print(isupper)
#> [1] TRUE

Join Elements into a Single String with a Separator

The strs_join function concatenates elements of an iterable using a separator.

# Join elements with a separator
joined <- strs_join("-", c("hello", "world"))
print(joined)
#> [1] "hello-world"

Left-justify String in a Field of a Given Width

The strs_ljust function left-justifies each element of a character vector in a field of a specified width.

# Left-justify a string
ljust <- strs_ljust("hello", 10)
print(ljust)
#> [1] "     hello"

Convert String to Lowercase

The strs_lower function converts each element of a character vector to lowercase, based on the specified locale.

# Convert strings to lowercase
lower <- strs_lower("HELLO WORLD")
print(lower)
#> [1] "hello world"

Left Strip Characters from a String

The strs_lstrip function removes leading characters (spaces by default) from each element of a character vector.

# Left-strip characters
lstrip <- strs_lstrip("    hello world")
print(lstrip)
#> [1] "hello world"

Normalize Whitespace in a String

The strs_normalize_whitespace function normalizes the whitespace in each element of a character vector.

# Normalize whitespace
normalized <- strs_normalize_whitespace("  hello   world  ")
print(normalized)
#> [1] "hello world"

Remove a Prefix from a String

The strs_removeprefix function removes a specified prefix from the start of each element of a character vector.

# Remove a prefix
removed_prefix <- strs_removeprefix("testString", "test")
print(removed_prefix)
#> [1] "String"

Remove a Suffix from a String

The strs_removesuffix function removes a specified suffix from the end of each element of a character vector.

# Remove a suffix
removed_suffix <- strs_removesuffix("StringTest", "Test")
print(removed_suffix)
#> [1] "String"

Replace Substring in a String

The strs_replace function replaces all occurrences of a specified substring in each element of a character vector.

# Replace a substring
replaced <- strs_replace("hello world", "world", "there")
print(replaced)
#> [1] "hello there"

Find the Last Occurrence of a Substring in a String

The strs_rfind function locates the last occurrence of a specified substring within each element of a character vector.

# Find the last occurrence of a substring
last_occurrence <- strs_rfind("hello world", "o")
print(last_occurrence)
#> [1] 8

 # 8

Right-justify String in a Field of a Given Width

The strs_rjust function right-justifies each element of a character vector in a field of a specified width.

# Right-justify a string
rjust <- strs_rjust("hello", 10)
print(rjust)
#> [1] "hello     "

Right Strip Characters from a String

The strs_rstrip function removes trailing characters (spaces by default) from each element of a character vector.

# Right-strip characters
rstrip <- strs_rstrip("hello world    ")
print(rstrip)
#> [1] "hello world"

Slice Substrings from a String

The strs_slice function extracts substrings from each element of a character vector, specified by start and stop positions.

# Slice substrings
sliced <- strs_slice("hello world", 1, 5)
print(sliced)
#> [1] "hello"

Split String into Substrings

The strs_split function splits each element of a character vector into substrings based on a separator.

# Split strings into substrings
split <- strs_split("hello world", " ")
print(split)  # list("hello", "world")
#> [[1]]
#> [1] "hello" "world"

Split String into Lines

The strs_splitlines function splits each element of a character vector into separate lines.

# Split strings into lines
split_lines <- strs_splitlines("hello\nworld\n")
print(split_lines)  # list("hello", "world")
#> [[1]]
#> [1] "hello" "world"

Check if String Starts With a Specified Prefix

The strs_startswith function determines whether each element of a character vector starts with a specified prefix.

# Check if strings start with a prefix
startswith <- strs_startswith("hello world", "hello")
print(startswith)
#> [1] TRUE

Strip Characters from Both Ends of a String

The strs_strip function removes leading and trailing characters (spaces by default) from each element of a character vector.

# Strip characters from both ends
strip <- strs_strip("    hello world    ")
print(strip)
#> [1] "hello world"

Convert String to Title Case

The strs_title function converts each element of a character vector to title case, based on the specified locale.

# Convert strings to title case
title <- strs_title("hello world")
print(title)
#> [1] "Hello World"

Convert String to Uppercase

The strs_upper function converts each element of a character vector to uppercase, based on the specified locale.

# Convert strings to uppercase
upper <- strs_upper("hello world")
print(upper)
#> [1] "HELLO WORLD"

Contributing

We welcome contributions to the strs package. If you have suggestions, bug reports, or want to contribute code, please open an issue or submit a pull request on our GitHub repository.

License

strs is released under the MIT License. See the LICENSE file in the package’s repository for more details.