Python Strings (With Examples)

PYTHON STRING:

A string in Python is a sequence of characters enclosed within single quotes (' ') or double quotes (" "). It is an ordered collection of characters that can include letters, digits, symbols, and whitespace. Strings are used to represent textual data and can be manipulated using various string methods and operations provided by the Python programming language.

Python Strings

• CREATING STRING IN PYTHON:

In Python, we create strings using single quotes (' '), double quotes (" "), and also triple quotes ('''  ''').

EXAMPLE:

• ACCESSING VALUE IN STRING:           

Accessing values in a string in Python involves using indexing to retrieve individual characters or portions of the string. Indexing starts at 0 for the first character and goes up to one less than the length of the string. You can also use negative indices to access characters from the end of the string.

EXAMPLE:       

ESCAPE CHARACTERS IN STRING:

Escape characters in Python strings are special characters that are used to represent characters that are difficult to input directly, such as newline characters, tab characters, or characters that have a special meaning in strings. Escape characters are denoted by a backslash (\) followed by a specific character or sequence of characters.   

Sr.	Escape Sequence	Description	Example
1.	\newline	It ignores the new line.	print("Python1 \ Python2 \ Python3") Output: Python1 Python2 Python3
2.	\\	Backslash	print("\\") Output: \
3.	\'	Single Quotes	print('\'') Output: '
4.	\\''	Double Quotes	print("\"") Output: "
5.	\a	ASCII Bell	print("\a")
6.	\b	ASCII Backspace(BS)	print("Hello \b World") Output: Hello World
7.	\f	ASCII Formfeed	print("Hello \f World!") Hello  World!
8.	\n	ASCII Linefeed	print("Hello \n World!") Output: Hello  World!
9.	\r	ASCII Carriege Return(CR)	print("Hello \r World!") Output: World!
10.	\t	ASCII Horizontal Tab	print("Hello \t World!") Output: Hello    World!
11.	\v	ASCII Vertical Tab	print("Hello \v World!") Output: Hello  World!
12.	\ooo	Character with octal value	print("\110\145\154\154\157") Output: Hello
13	\xHH	Character with hex value.	print("\x48\x65\x6c\x6c\x6f") Output: Hello

 

STRING OPERATOR:

Python provides several operators that you can use with strings to perform various operations, such as concatenation, repetition, and comparison.

Operator	Description	Example
+	Concatenation - Adds values on either side of the operator	a + b will give HelloPython
*	Repetition - Creates new strings, concatenating multiple copies of the same string	a*2 will give -HelloHello
[]	Slice - Gives the character from the given index	a[1] will give e
[ : ]	Range Slice - Gives the characters from the given range	a[1:4] will give ell
in	Membership - Returns true if a character exists in the given string	H in a will give 1
not in	Membership - Returns true if a character does not exist in the given string	M not in a will give 1
r/R	Raw String - Suppresses actual meaning of Escape characters. The syntax for raw strings is exactly the same as for normal strings with the exception of the raw string operator, the letter "r," which precedes the quotation marks. The "r" can be lowercase (r) or uppercase (R) and must be placed immediately preceding the first quote mark.	print r'\n' prints \n and print R'\n'prints \n
%	Format - Performs String formatting	See at next section

STRING BUILT-IN FUNCTION:

Python provides a variety of built-in functions that you can use to manipulate and work with strings

 

Sr.No.	Methods with Description
1	capitalize() Capitalizes first letter of string
2	center(width, fillchar) Returns a space-padded string with the original string centered to a total of width columns.
3	count(str, beg= 0,end=len(string)) Counts how many times str occurs in string or in a substring of string if starting index beg and ending index end are given.
4	decode(encoding='UTF-8',errors='strict') Decodes the string using the codec registered for encoding. encoding defaults to the default string encoding.
5	encode(encoding='UTF-8',errors='strict') Returns encoded string version of string; on error, default is to raise a ValueError unless errors is given with 'ignore' or 'replace'.
6	endswith(suffix, beg=0, end=len(string)) Determines if string or a substring of string (if starting index beg and ending index end are given) ends with suffix; returns true if so and false otherwise.
7	expandtabs(tabsize=8) Expands tabs in string to multiple spaces; defaults to 8 spaces per tab if tabsize not provided.
8	find(str, beg=0 end=len(string)) Determine if str occurs in string or in a substring of string if starting index beg and ending index end are given returns index if found and -1 otherwise.
9	index(str, beg=0, end=len(string)) Same as find(), but raises an exception if str not found.
10	isalnum() Returns true if string has at least 1 character and all characters are alphanumeric and false otherwise.
11	isalpha() Returns true if string has at least 1 character and all characters are alphabetic and false otherwise.
12	isdigit() Returns true if string contains only digits and false otherwise.
13	islower() Returns true if string has at least 1 cased character and all cased characters are in lowercase and false otherwise.
14	isnumeric() Returns true if a unicode string contains only numeric characters and false otherwise.
15	isspace() Returns true if string contains only whitespace characters and false otherwise.
16	istitle() Returns true if string is properly "titlecased" and false otherwise.
17	isupper() Returns true if string has at least one cased character and all cased characters are in uppercase and false otherwise.
18	join(seq) Merges (concatenates) the string representations of elements in sequence seq into a string, with separator string.
19	len(string) Returns the length of the string
20	ljust(width[, fillchar]) Returns a space-padded string with the original string left-justified to a total of width columns.
21	lower() Converts all uppercase letters in string to lowercase.
22	lstrip() Removes all leading whitespace in string.
23	maketrans() Returns a translation table to be used in translate function.
24	max(str) Returns the max alphabetical character from the string str.
25	min(str) Returns the min alphabetical character from the string str.
26	replace(old, new [, max]) Replaces all occurrences of old in string with new or at most max occurrences if max given.
27	rfind(str, beg=0,end=len(string)) Same as find(), but search backwards in string.
28	rindex( str, beg=0, end=len(string)) Same as index(), but search backwards in string.
29	rjust(width,[, fillchar]) Returns a space-padded string with the original string right-justified to a total of width columns.
30	rstrip() Removes all trailing whitespace of string.
31	split(str="", num=string.count(str)) Splits string according to delimiter str (space if not provided) and returns list of substrings; split into at most num substrings if given.
32	splitlines( num=string.count('\n')) Splits string at all (or num) NEWLINEs and returns a list of each line with NEWLINEs removed.
33	startswith(str, beg=0,end=len(string)) Determines if string or a substring of string (if starting index beg and ending index end are given) starts with substring str; returns true if so and false otherwise.
34	strip([chars]) Performs both lstrip() and rstrip() on string.
35	swapcase() Inverts case for all letters in string.
36	title() Returns "titlecased" version of string, that is, all words begin with uppercase and the rest are lowercase.
37	translate(table, deletechars="") Translates string according to translation table str(256 chars), removing those in the del string.
38	upper() Converts lowercase letters in string to uppercase.
39	zfill (width) Returns original string leftpadded with zeros to a total of width characters; intended for numbers, zfill() retains any sign given (less one zero).
40	isdecimal() Returns true if a unicode string contains only decimal characters and false otherwise.