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Python String Methods

method	description
capitalize	makes first character is upper case and rest lower case.
index	index returns given sub string's first index
isspace	string has atleast one or more spaces , then returns True,otherwise False
removesuffix	If the given string ends with given string , removes it and returns new string
startswith	is string starts with given substring
casefold	Return a version of the string suitable for caseless comparisons.
isalnum	Returns true if String contains alpha-numeric otherwise Fase.
istitle	If first character is in Upper case returns True other-wise False
replace	replaces the given string with all characters of the substring, if count is given then replaces according to count occurances.
strip	Removes leading and trailing spaces
center
isalpha	Returns True if all characters are alphabetic otherwise False
isupper	All characters are in upper case returns True or False
rfind	returns highest index if sub string is found, otherwise -1
swapcase	converts all lower case letters to upper case,all upper case letters to lower case
count	counts occurance of given character
isascii	is string contains all ascii characters
join	Concatenate any number of Strings
rindex	returns highest index if sub string is found, otherwise raises exception ValueError
title	Converts every word starting character as Upper Case
encode
isdecimal	Returns True, if string is Decimal String , othwerwise False
ljust
rjust
translate
endswith	checks string ends with specified characters
isdigit	does string has only numbers
lower	converts all upper case characters to lower case
rpartition
upper	converts all lower case characters to upper case
expandtabs	Expands all tabs using spaces and returns a new string
isidentifier	Returns True,string is valid Python Identifier
lstrip	trims left side spaces
rsplit
zfill	Pad a numeric string with zeros on the left, to fill the field of the given width
find	searches the string for a given substring, if found returns lowest index,otherwise -1
islower	all characters in the string is lower case returns True else False
maketrans
rstrip	trims right side spaces
format
isnumeric	string has all numbers,return True else False
partition	Partition the string into 3 parts
split	split based on delimter, returns list
format_map
isprintable	String returns True, if all characters are consedered in repr() as printable, otherwise False
removeprefix	if the string starts with the given string removes it, returns new string
splitlines	splits string based on newline character,returns list

String capitalize, title methods

capitalize method makes first character as Upper case letter, remaining all lower case
title method , makes every word's first letter as upper case

	>>> sports='gymnastics is a sport'
	>>> sports.capitalize()
	'Gymnastics is a sport'
	>>>

		>>> game_name='The Expanse: a telltale series, cost is $99.99'
		>>> game_name.title()
		'The Expanse: A Telltale Series, Cost Is $99.99'
		>>>

String join method

Initial string which called this method,is going to be inserted between in given string.

	  >>> init=' '
	  >>>

--init string is space character, it is going to stuffed/inserted between each character.
		>>>init.join('abc')
		'a b c'

Note: Python String join method , is different from java string join method.

Insert dot between each item in the list or to form a IP Address note:each item in the list should a string

		>>>
		>>>
		>>>'.'.join(['127','0','0','1'])
		'127.0.0.1'

String find , index, count methods

find,index count has similar functionality, search for a given character or substring. if it finds returns index , otherwise some methods throw exception, some methods throw -1 etc.,

Choose appropriate method for your requirement. Here is the string

	s = 'they began to hoard food and save money'

index method

index method ,returns index number starting from 0 to length-1, if found otherwise ValueError exception is thrown.

		>>>s.index('t') 
		0 
		
		't' is found at index 0(lowest index). 't' found many places in above string, bu returns lowest index
		
		>>>s.index('save')
		29
		'save' substring is found at starting index 29.
		
		>>>s.index('zoo')
		ValueError: substring not found
		
		catch the ValueError exception
		--------------------------------
		>>> try:
		...   s.index('zoo')
		... except: print('zoo not found')
 
		zoo not found

find method

find method ,returns index number starting from 0 to length-1, if found otherwise -1.

		>>>s.find('t') 
		0 
		
		't' is found at index 0(lowest index). 't' found many places in above string, but returns lowest index
		
		>>>s.find('save')
		29
		'save' substring is found at starting index 29.
		
		>>>s.find('zoo')
		-1
		
		substring 'zoo' not found , returns -1

count method

count method ,returns count of substring, if found otherwise 0 occurances.

		>>>s.count('t')
		2
		letter 't' found in 2 places
		>>>s.count('a')
		4  letter 'a' found in 4 places
		>>>s.count('an')
		2
		substring 'an' found in 'began' and 'and'
		
		>>>s.count('zoo')
		0
		
		substring 'zoo'  not found in string s

String rfind, rindex methods

find method returns lowest-index, rfind returns highest-index.
similarly rindex returns highest index.

String strip,rstrip ,lstrip Methods

All these strip methods removes trailing and leading empty spaces in a string

String strip method

	----Removes leading and trailing empty spaces and creates a new string 
	>>>s='   they began to hoard   '
	'they began to hoard'

	 -- Removes special symbols like >>>> and <<<<, (leading and trailing), special symbols should be passed to strip method.
	>>> ">>>> This is is email body <<<<<".strip('><')
	' This is is email body '

String lstrip method

	-- removes leading spaces using lstrip method
	>>>"  you been fired".lstrip()
	'you been fired'

String rstrip method

	-- removes trailing spaces using rstrip method
	>>>"you are hired as Senior Manager  ".rstrip()
	'you are hired as Senior Manager'

String upper, lower , isupper,islower,isdigit methods

These methods changes the aplhabets into upper or lower case.

String upper method

>>>s='cheetahs are the fastest living land animals'
>>>s.upper()
'CHEETAHS ARE THE FASTEST LIVING LAND ANIMALS'

String lower method

	>>>s='CHEETAHS ARE THE FASTEST LIVING LAND ANIMALS'
	>>>s.lower()
	'cheetahs are the fastest living land animals'

String islower,isupper method

 >>>sports='tennies'
 >>>sports.isupper()
 False
 >>>sports.islower()
 True
 >>>

String isdigit method

Checks entire string has numbers only

	>>>s='0123456'
	>>>s.isdigit()
	True
	--if string has only digits, then using this method can convert to int type
	
	>>>i=int(s)

Mix upper and lower methods

You can mix string methods as a pipe in UNIX or Fluent API in java.
as shown below
here calling upper and lower methods in same statement.

	>>>s='tortoise'
	>>>s.upper()
	TORTOISE
	>>>s.upper().lower()
	'tortoise'

String split and splitlines method

split & splitlines methods returns a list, split splits based on delimiter, by default delimiter is space, otherwise user specified one. for splitlines delimiter is new line

String split method

	-- here delimiter is  color(:)
	>>>s='name:sam'
	>>>s.split(':')
	['name','sam']
	
	-- convert INDIA into a list  'I",'N','D','I','A'
	>>>s='INDIA'
	>>>' '.join(s).split()
	['I",'N','D','I','A']

String splitlines method

splitlines method splits string using newline as delimter, returns list

>>> s="this is first line\nthis is second line\nthis is third line"
>>> s.splitlines()
['this is first line', 'this is second line', 'this is third line']

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