Python is a programming language of exceptional versatility, offering a wide range of applications. One of its most prevalent uses is in manipulating and handling strings.
In this article, we will delve deep into Python’s various string methods and gain a comprehensive understanding of how to employ them effectively for optimal results.
See Also: How To Use Python With Open Statement?
Table of Contents
String Methods in Python
In Python, a string is a sequence of characters represented by the “str” data type. Strings are immutable, meaning their value cannot be altered once created. Nevertheless, this immutability helps the ability to manipulate strings through various methods. This Guide will explore some of Python’s most common string methods.
Python string is a sequence of Unicode characters that can be enclosed by double or, more commonly, single quotes.
Point to be noted: These string methods in Python do not alter the initial string. Instead, they return new string values as the output of these methods, which have changed attributes.
len()
The first method we will delve into is the “len()” function. This function determines the length of a string. For example, in the case of a string “Good Morning,” the len() function would return the value 12, as there are 12 characters in the string.
strip()
The following method is the “strip()” method. This method removes leading and trailing whitespaces from a string. For example, if we have a string “Good Morning “, the strip() method will return the value “Good Morning” by removing the leading and trailing whitespaces.
replace()
The “replace()” method is another commonly used string method. This method replaces a specific substring with another substring. For example, if we have a string “Good Morning” and we want to replace the word “Morning” with “Afternoon,” we would use the replace() method as follows:
spilt()
The “split()” method splits a string into a list of substrings based on a specified delimiter. For example, if we have a string “Good Morning” and we want to split it into a list of words, we would use the split() method as follows:
join()
The “join()” method serves as the inverse of the “split()” method. This method concatenates a series of strings into a single string using a pre-specified delimiter. For instance, if we were to have a list of words [“Good”, “Morning”] and desired to combine them into the single string “Good Morning,” we would use the join() method in the following manner:
find()
To locate the first occurrence of a specific substring within a string, use the “find()” function. For example, if we have a string “Good Morning” and we want to find the index of the word “Morning,” the result would be ‘5,’ and we would use the find() method as follows:
count()
The “count()” method determines the frequency of a specific substring within a string. For instance, if we were to use the string “Good Morning” and wish to determine the number of occurrences of the letter “l” (answer: 1), we would use the count() method as illustrated:
upper()
A string’s characters can convert to uppercase using the “upper()” function. For example, if we have a string “Good Morning” and we want to convert it to “GOOD MORNING,” we will use the upper() method as follows:
lower()
The “lower()” method serves as the inverse of the “upper()” method. It converts all characters within a string to lowercase. For instance, when working with the string “Good Morning” and the desire is to convert it to “good morning”, use the lower() method as follows:
Other String Methods In Python
Understanding and mastering these methods allows you to quickly manipulate and work with strings in your Python projects. However, it’s important to note that this is not an exhaustive list of all string methods available in Python. You can utilize many more ways and functionality to manipulate and work with strings in Python.
Method | Function |
---|---|
capitalize() | It changes the string's beginning character to uppercase |
casefold() | It changes all of the string's characters to lower case |
center() | It centers the string with the specified value and gives it back as the output |
count() | It provides the frequency with which a certain value appears in a string |
encode() | It encodes the string and returns the new encoded value |
endswith() | If the string concludes with the specified value, the output is returned as "True" |
expandtabs() | It sets the tab size to a specified value to replace the “\t” in the string |
find() | Looks for a specific value in the string, then gives out the position of its first occurrence |
format() | In the string, it formats the specified values |
format_map() | Just like format, it formats the specified values in the string |
index() | Looks for a specific value in the string, then gives out the position of its first occurrence |
isalnum() | The output is returned as "True", only if all the characters in the string qualify as alphanumerics |
isalpha() | The output is returned as "True", only if all the characters in the string qualify as letters of the alphabet |
isascii() | The output is returned as "True", only if all the characters in the string qualify as ASCII characters |
isdecimal() | The output is returned as "True", only if all the characters in the string qualify as decimals |
isdigit() | The output is returned as "True", only if all the characters in the string qualify as digits |
isidentifier() | If the string is an identifier, the output is returned as "True" |
islower() | The output is returned as "True" only if all letters in the string are lowercase |
isnumeric() | The output is returned as "True", only if all the characters in the string qualify as numerics |
isprintable() | The output is returned as "True", only if all the characters in the string qualify as printable |
isspace() | The output is returned as "True", only if all the characters in the string qualify as whitespaces |
istitle() | If the string is titlecased, the output is returned as "True" |
isupper() | The output is returned as "True" only if all letters in the string are uppercase |
join() | It joins or links the elements into a string |
ljust() | It left aligns the string and returns the new version |
lower() | It converts the string into lowercase and returns the new version |
lstrip() | It trims the string from the left, and returns the new version |
maketrans() | It gives out a translation table to use in translations |
partition() | It gives out a tuple, in which the string is divided into three parts |
replace() | It gives out a string, in which a specified value is replaced with a different specified value |
rfind() | It looks for a specified value in the string, and gives back the position of where it was last found |
rindex() | It looks for a specified value in the string, and gives back the position of where it was last found |
rjust() | It trims the string from the right, and returns the new version |
rpartition() | It gives out a tuple, in which the string is divided into three parts |
rsplit() | It divides the string from the right, at the specified separator, and gives back a list |
rstrip() | It right trims the string and returns the new version |
split() | It divides the string at the specified separator, and gives back a list |
splitlines() | It divides the string at line breaks and gives back a list |
startswith() | If the string starts with the specified value, the output is returned as "True" |
strip() | It trims the string from both sides and returns the new version |
swapcase() | It swaps the cases of the characters in the string, i.e., lower case becomes upper case and vice versa |
title() | It converts the to title case |
translate() | It translates the string and gives back the new version |
upper() | It converts the entire string into upper case |
zfill() | It fills the string with a certain specified number of 0 values at the beginning |
FAQs
How do you convert a string to uppercase in Python?
You can convert a string to uppercase in Python using the upper() method. For example, the string 'hello' can be converted to 'HELLO' using the code: 'hello’.upper()
How do you check if a string contains a specific substring in Python?
You can check if a string contains a specific substring in Python using the in a keyword or the find() method. The in keyword returns a boolean value indicating whether the substring is present in the string, while the find() method returns the index of the first occurrence of the substring or -1 if the substring is not found.
How do you split a string into a list of substrings in Python?
You can split a string into a list of substrings in Python using the split() method. The split() method takes a delimiter as an argument. It returns a list of substrings separated by the delimiter.
How do you remove whitespace from a string in Python?
You can remove whitespace from a string in Python using the strip() method. The strip() method removes the string's leading or trailing whitespace.
How do you get the length of a string in Python?
You can get the length of a string in Python using the len() function. The len() function takes a string as an argument and returns the number of characters.
Conclusion
Python has various string techniques that may modify and interact with strings. Mastering these techniques will allow you to create more effective and reusable code. This Guide comprehensively overviews some of the most commonly used string methods. Still, exploring the official Python documentation for more information on string methods and other functionality is always a good idea. See how to do linear programming in Python.
See Also: How To Set Environment Variables In Python