Python String Functions

Introduction to Python String Functions

Various string methods such as center(), count(), find(), format(), index(), isalnum(), lower(), maketrans(), replace()etc. are incorporated by Python environment, and that are provided as in-built tools to the user, so that the user can manipulate the text data, perform requisite operations over the string, in the context of text analysis, based on the requirement, are termed as Python string functions.

Datatypes of Python String Functions

Python consists of five main data types, namely below:

• Numeric (sub-types of which are – int, long, float and complex)
• String
• List
• Tuple
• Dictionary

For Example:

Code:

str1 = ‘Hello from EduCBA’
OR
Str2 = “Hello from EduCBA”

In this article, we will take a closer look at the String data type and its functions. Single and double quotes are made use of when assigning a string value to a variable.

Python String Functions

The following are the python string function mentioned:

1. capitalize(): Converts the initial letter of the string to uppercase.

Example:

Code:

str1 = “hello from EduCBA”
str2 = str1.capitalize()
print(str2)

Output:

Hello From EduCBA

2. casefold(): Converts the entire string to lowercase.

Example:

Code:

str1 = “HELLO FROM EduCBA”
str2 = str1.casefold()
print(str2)

Output:

hello from educba

3. center(): It aligns the string at the center of the specified length.

Example:

Code:

str1 = “EduCBA”
str2 = str1.center(10)
print(str2)

Output:

EduCBA

That is, two-character spaces on the left have left a void, followed by six characters of the string and another two void characters on the right, summing to a total of ten characters.

4. count(): Returns the number of times a substring occurs in the given string.

Example:

Code:

str1 = “Hello from EduCBA. Welcomw to EduCBA”
num = str1.count(“EduCBA”)
print(str2)

Output:

2

5. encode(): Converts the string into its encoded version.

Example:

Code:

str1 = “EduCBA”
str2 = str1.encode()
print(“Hello from”, str2)

Output:

Hello from vfg/7hyt/4

6. endswith(): Returns true if the given string ends with the specified substring.

Example:

Code:

str1 = “Hello from EduCBA”
str2 = str1.endswith(“CBA”)
print(str2)

Output:

true

7. expandtabs(): Replaces the tab size to the given numeric character spaces. The default tab size is 8 character spaces.

Example:

Code:

str1 = “Hello\tfrom\tEduCBA”
str2 = str1.expandtabs(2)
print(str2)

Output:

Hello from EduCBA

8. find(): Searches the main string from the left for a specified substring and returns its position within a match is found; if not, return -1 when no match is found.

Example:

Code:

str1 = “Hello from EduCBA”
str2 = str1.find(“EduCBA”)
print(str2)

Output:

11

9. format(): Helps format the string by making use of placeholders.

Example:

Code:

str1 = “EduCBA”
print("Hello from {}.".format(str1))

Output:

Hello from EduCBA.

10. index(): Finds the position of occurrence of a substring by searching the main string for a specified substring and returns its position within a match is found, if not throws an error.

Example:

Code:

str1 = “Hello from EduCBA”
str2 = str1.index(“EduCBA”)
print(str2)

Output:

11

11. isalnum(): Determines if all the characters in a given string are alphanumeric, that is, only alphabets and numbers. If yes, then returns true, else returns false. In case there is a space in between, it returns false.

Example:

Code:

str1 = “EduCBA123”
str2 = str1.isalnum()
print(str2)

Output:

True

12. isalpha(): Determines if all the characters in the given string are alphabets. If yes, return true, else return false. In case there is a space in between, it returns false.

Example:

Code:

str1 = “HellofromEduCBA”
str2 = str1.isalpha()
print(str2)

Output:

True

13. isdecimal(): Determines if all the characters in a given string are decimals. If yes, then returns true, else returns false. In case there is a space in between, it returns false.

Example:

Code:

str1 = “123456”
str2 = str1.isdecimal()
print(str2)

Output:

True

14. isidentifier(): Determines whether or not the string is a valid identifier. If yes, then returns true, else returns false. In case there is a space in between, it returns false.

Example 1:

Code:

str1 = “EduCBA123”
str2 = str1.isidentifier()
print(str2)

Output:

True

Example 2:

Code:

str1 = “EduCBA 123”
str2 = str1.isidentifier()
print(str2)

Output:

False

15. islower(): Determines if all the characters in a given string are in lower case. If yes, then returns true, else returns false.

Example:

Code:

str1 = “EduCBA”
str2 = str1.islower()
print(str2)

Output:

False

16. isnumeric(): Determines if all the characters in a given string are numeric, that is, numbers and exponents that could be in fractions. If yes, then returns true, else return false.

Example:

Code:

str1 = “123”
str2 = str1.isnumeric()
print(str2)

Output:

True

17. isprintable(): Determines if all the characters in a given string are printable or not. If yes, then returns true, else returns false. Characters such as “\t” or “\n” are not printable.

Example 1:

Code:

str1 = “EduCBA123”
str2 = str1.isprintable()
print(str2)

Output:

True

Example 2:

Code:

str1 = “\tEduCBA123”
str2 = str1.isprintable()
print(str2)

Output:

False

18. isspace(): Determines if all the characters in a given string are white spaces. If yes, then returns true, else returns false.

Example:

Code:

str1 = “     “
str2 = str1.isspace ()
print(str2)

Output:

True

19. istitle(): Determines if a string follows a set of rules to qualify as a title. If yes, then returns true, else returns false.

Example:

Code:

str1 = “Hello From Educba”
str2 = str1.istitle()
print(str2)

Output:

True

20. isupper(): Determines if all the characters in a given string are in the upper case. If yes, then returns true, else returns false.

Example:

Code:

str1 = “HELLO FROM EDUCBA”
str2 = str1.isupper()
print(str2)

Output:

True

21. join(): Meant to concatenate two strings in an iterated manner.

Example:

Code:

str1 = “Hello”
str2 = str1.join(“EduCBA”)
print(str2)

Output:

HelloEHellodHellouHelloCHelloBHelloA

22. lower(): Meant to convert the entire string to lower case.

Example:

Code:

str1 = “Hello from EduCBA.”
str2 = str1.lower()
print(str2)

Output:

hello from educba.

23. upper(): Meant to convert the entire string to the upper case.

Example:

Code:

str1 = “Hello from EduCBA”
str2 = str1.upper()
print(str2) Output: HELLO FROM EDUCBA 24. replace(): Meant to replace a substring with another. Example: Code:

str1 = “Hello from EduCBA!”
str2 = str1.replace(“ from”,” there”)
print(str2)

Output:

Hello there EduCBA!

Conclusion

These are few of the important string functions that are commonly used. Being through these methods makes it easier and faster for one to develop code when working with strings.

Recommended Articles

This has been a guide to Python String Functions. Here we discussed the basic concept with important python string functions in detail. You can also go through our other suggested articles to learn more –

1. Hive String Functions
2. Python Commands
3. Python Frameworks
4. Python String Join