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On compiling and running the above program, this will produce the following result :

OOOOOOOOthis is string example….wow!!! 000000000000000000this is string 

example…. wow!!!

Min character: ! 

Min character: !

The following code is-

True False

Output 

Max character: y 

Max character: x 

Output

[‘Linel-a b c d e f’, ‘Line2- a b c’, “, ‘Line4- abed’] 

[‘Linel-a b c d e f’, ‘Line2- a b c’, “, ‘Line4- abed’] 

[‘Linel-a b c d e f\ri, ‘Line2- a b c\ri, ‘\n’, ‘Line4- a b c d’] 

[‘Linel-a b c d e f\n’, ‘Line2- a b c\ri, ‘\ri, ‘Line4- a b c d’] 

[‘Linel-a b c d e f\ri, ‘Line2- a b c\ri, ‘\n’, ‘Line4- a bed’]

The method strip( ) returns a copy of the string in which all chars have been stripped from the beginning and the end of the string (default whitespace characters)

Syntax: str.strip([chars]);

The method isdecimal( ) checks whether the string consists of only decimal characters. 

This method are present only on Unicode objects. Below is the example. 

Syntax

str.isdecimal( ) 

Example 

# !/usr/bin/python 

str = u”this2009″; 

print str.isdecimal( ); 

str = u”23443434″; 

print str.isdecimal( );

This will produce the following result : 

False 

True

The method split( ) returns a list of all the words in the string, using str as the separator (splits on all whitespace if left unspecified), optionally limiting the number of splits to num.

Syntax

str.split(str=””, num=string.count(str)). 

Parameters 

str — This is any delimeter, by default it is space. 

num — This is number of lines to be made.

Example

# !/usr/bin/python

str = “Linel-abcdef \nLine2-abc \nLine4-abcd”;

print str.split( ); print str.split(‘ 1 );

OUTPUT

[‘Linel-abcdef’, ‘Line2-abc’, ‘Line4-abcd’] 

[‘Linel-abcdef’, ‘\nLine2-abc \nLine4-abcd’]

Strings are immutable means that the contents of string cannot be chrnged after it is created.

For example : 

>>> str = ‘Meney’ 

>>> str [3] = ‘h’

Type Error : ‘str’ object not support item assignment Python does not allow to change a character in a string. So an attempt to replace ‘e’ in the string by ‘h’ displays a Type Error.

string = raw_input (“Enter a string:”) 

length = len (string) 

string2 = ” ”

for a in range (0, length, 2): 

string 2 + – string [a]

if a < (length-1): 

string 2+ = string [a+1],upper() 

print “Original string is”, string 

print “Converted string is”, string2

email = raw_input (“Enter email ID :”) 

domain = “@gmail.com” 

lendo = len(domain) 

lenm = len(email) 

sub = email [lenm – lendo:]

if sub = = domain : 

if lendo ! = lenm : 

print “It is a valid email ID” 

else :

print “It is an invalid email ID” 

else : 

print “It’s domain is different”

def wsearch ( ) :

 imprt re 

word = ‘good’

search1 = re.search (word, ‘I am a good person’) if search1 :

position = search1.start ( ) 

print “matched”, word, “at position”, position 

else :

print “No match found”

def palindrom ( ) : 

str = input (“Enter the string”) 

l = len (str) 

P = l – 1 

inex = 0

while (index < p) : 

if (str[index] = = str [p]): 

index = index + 1

p = p-1 else : 

print “String is not a palindrom” break 

else : 

print “String is a palindrom” 

def letcount ( ) :

word = ‘successor’ 

count = 0 

for letter in word :

if letter = = ‘s’ : 

count = count + 1 

print (count)

Output 

this is string example….wow!!! 

this is string example..,.wow!!!8888888

string = raw_input (“Enter a string :”) 

length = len (string) 

a = 0 end – length

string 2 = ” # empty string 

while a < length 

if a == 0 

string 2 += string [0].upper() 

a += 1

elif (string [a] = = ‘ ‘ and string [a+1) !=”) : 

string 2 + = string [a] 

string 2 + = string [a+l].upper( ) 

a + = 2

else : 

string 2 + = string [a] 

a + = 1 

print “Original string :”, string 

print “Converted string :”, string2

def reverseorder(list 1) :

relist = [ ] 

i = len (list 1) -1 

while i > = 0 : 

relist.append (list [i]) 

i = 1 -1 return relist

The method expandtabs( ) returns a copy of the string in which tab characters ie. ‘\t’ have been expanded using spaces, optionally using the given tabsize (default 8).

Syntax

Following is the syntax for expandtabs( ) method : str.expandtabs(tabsize=8)

Example 

#!/usr/bin/python 

str = “this is\tstring example….wow!!!”;

print “Original string: ” + str; 

print “Defualt exapanded tab: ” +

str.expandtabs( ); 

print “Double exapanded tab: ” + str.

expandtabs(16);

OUTPUT 

Original string: this is string example….wow!!! Defualt exapanded tab: this is string example…. wow!!! 

Double exapanded tab: this is string example…. wow!!! 

The method zfill( ) pads string on the left with zeros to fill width.

Syntax : str.zfill(width)

Parameters: This is final width of the string. This is the width which we would get after filling zeros. Return Value: This method returns padded string

Following is the syntax for capitalize( ) method : str.capitalize( )

The method maketrans( ) returns a translation table that maps each character in the intab string into the character at the same position in the outtab string. Then this table is passed to the translate( ) function.

Syntax : str.maketrans(intab, outtab]);

Following is the syntax for find( ) method : str.find(str, beg=0 end=len(string))

Following is the syntax for isalpha( ) method : str.isalpha( )

The method islower( ) checks whether all the case-based characters (letters) of the string are lowercase

The method translate( ) returns a copy of the string in which all characters have been translated using table (constructed with the maketrans( ) function in the string module), optionally deleting all characters found in the string deletechars

The given code will produce following result : 

th3s 3s str3ng 21pl2….w4w!M

Above code will produce the following result : 

5 

5 

-1 

2 

2 

-1

The following example shows the usage of swapcase( ) method. 

# !/usr/bin/py thon

str = “this is string example….wow!!!”;

print str.swapcase( ); 

str = “THIS IS STRING EXAMPLE….WOW!!!”; print str.swapcase( );

This will produce the following result : 

THIS IS STRING EXAMPLE….WOW!!! 

this is string example….wow!!!

The following example shows the usage of title( ) method 

# !/usr/bin/python 

str = “this is string example….wow!!!”;

print str.title( ); 

On compile and run the above program, this will produce the following result : 

This Is String Example….Wow!!!

In Python strings, each individual character is ! given a location number, called “index” and this process is called “indexing”. Python allocates indices in two directions :

1. in forward direction, the indexes are numbered as 0,1, 2, length-1. 

2. in backward direction, the indexes are numbered as -1, -2, -3,…. length. This is known as “two-way indexing”.

Traversing a string means accessing all the elements of the string one after the other by using the subscript. A string can be traversed using for loop or while loop. 

For example :

A = ‘Python’

i = 0

while i < lenn (A) :

print A[i] 

i = i + 1

Output : 

P

y 

t

h 

o 

n

Normal strings in Python are stored internally as 8-bit ASCII, while Unicode strings are stored as 16- bit Unicode. This allows for a more varied set of characters, including special characters from most languages in the world.

Example…….

#!/usr/bin/python 

print u’Hello, world!’

The following code. is -

True 

False

Output : [‘sing’, ‘sing’]

Justification : fmdall( ) finds all occurences of the given substring with 

metacharacter.

The output would be “N match found” 

Justification : re.search( ) rill attempt the pattern throughout the string, i ntil it finds a match. re.match( ) on the other hand, only attempts the pattern at the very start of the string.

Example :

>>>re.match(“d”, “abcdef’) # No match >>>re.search(“d”, “abcdef’) # Match

string = raw_input (“Enter a string :”) 

length = len (string) 

max length = 0 

max sub = ‘ ‘ 

sub = ‘ ‘ lensub = 0

for a in range (length) : 

if string [a] in aeiou ‘or string [a] in’AEIOU’: 

if lensub > maxlength : 

maxsub = sub 

maxlength – lensub 

sub = ‘ ‘ lensub 0

else : 

sub += string[a]

 lensub = len(sub) 

a + = 1 

print “Maximum length consonent 

substring is :”, maxsub, 

print “with”, maxlength, “characters”

The method replace( ) returns a copy of the string in which the occurrences of old have been replaced with new, optionally restricting the number of replacements to max. 

Syntax 

str.replace(old, new[, max]) 

Parameters –

old — This is old substring to be replaced. 

new — This is new substring, which would replace old substring. 

max — If this optional argument max is given, only the first count occurrences are replaced.

Example 

# !/usr/bin/python

str = “this is string example….wow!!! this is really string”; 

print str.replace(“is”, “was”); print str.replace(“is”, “was”, 3);

OUTPUT

thwas was string example….wow!!! thwas was really string 

thwas was string example….wow!!! thwas is really string

The method encode( ) returns an encoded version of the string. Default encoding is the current default string encoding.