String Functions

String Functions

len(str)

Returns the length (no of characters) of the string.

Example:

>>> A="Corporation"
>>> print(len(A))

Output:

11

capitalize( )

 Used to capitalize the first character of the string

Example:

>>> city="chennai"
>>> print(city.capitalize())

Output:

Chennai

center(width, fillchar) 

Returns a string with the original string centered to a total of width columns and filled with fillchar in columns that do not have characters

Example:

>>> str1="Welcome"
>>> print(str1.center(15,'*') )

Output:

****Welcome****

find(sub[, start[, end]])

The function is used to search the first occurrence of the sub string in the given string. It returns the index at which the substring starts. It returns -1 if the substring does not occur in the string.

Example:

>>>str1=’mammals’
>>>str1.find(‘ma’)

Output:

0

On omitting the start parameters, the function starts the search from the beginning.

Example:

>>>str1.find(‘ma’,2)

Output:

3

Example:

>>>str1.find(‘ma’,2,4)

Output:

-1

Displays -1 because the substring could not be found between the index 2 and 4-1.

isalnum( )

Returns True if the string contains only letters and digit. It returns False. If the string contains any special character like _, @, #, *, etc.

Example;

>>>str1=’Save Earth’
>>>str1.isalnum()

Output:

False

The function returns False as space is an alphanumeric character.

Example:

>>>’Save1Earth’.isalnum()

Output:

True

isalpha( )

Returns True if the string contains only letters. Otherwise return False.

Example:

>>>’Click123’.isalpha()

Output:

False

Example;

>>>’python’.isalpha( )

Output:

True

isdigit( )

Returns True if the string contains only numbers. Otherwise it returns False.

Example:

>>> str1=’Save Earth’
>>>print(str1.isdigit( ))

Output:

False

lower( )

Returns the exact copy of the string with all the letters in lowercase.

Example:

>>>str1=’SAVE EARTH’
>>>print(str1.lower())

Output:

save earth

islower( )

Returns True if the string is in lowercase.

Example:

>>> str1=’welcome’

>>>print (str1.islower( ))

Output:

True

isupper( )

Returns True if the string is in uppercase.

Example:

>>> str1=’welcome’
>>>print (str1.isupper( ))

Output:

False

upper( )

Returns the exact copy of the string with all letters in uppercase.

Example:

>>> str1=’welcome’

>>>print (str.upper( ))

Output:

WELCOME

title( )

Returns a string in title case

Example:

>>> str1='education department'
>>> print(str1.title())

Output:

Education Department

swapcase( )

It will change case of every character to its opposite case vice-versa.

Example:

>>> str1="tAmiL NaDu"
>>> print(str1.swapcase())

Output:

TaMIl nAdU