String In Python

Definition: A string is a Sequence of one or more characters (Letters, numbers, symbols) enclosed in single, double or triple quotation marks.

                                                                                    OR

A string is a sequence of characters enclosed within quotes. You can use either single ('hello') or double ("hello") quotes to define a string.

Example:

# Using single quotes

name = 'Naitik'

# Using double quotes

greeting = "Hello, world!"

# Using triple quotes for multi-line strings

message = """This is

a multi-line

string."""

Basics of String:

Ø Strings in Python are immutable, which means they cannot be changed after they are created. If you modify a string, Python creates a new one instead.

Ø Each character has its index or can be accessed using its index.

Ø String in python has two-way index for each location. (0, 1, 2, ……. In the forward direction and -1, -2, -3, …….. in the backward direction.)

Example:  str=”prakash”    # Total length of string is 7

                    

            The index of string in forward direction starts from 0 and in backward direction starts from  -1.

   The size of string is total number of characters present in the string. (If there are n characters in the string, then last index in forward direction would be n-1 and last index in backward direction would be –n.)

           String are stored each character in contiguous location.

         The character assignment is not supported in string because strings are immutabl

>>>s=’Python’ >>>type(s)	>>>s1=”Python” >>>type(s1)	>>>s2=”’Programming”’ >>>type(s2)	>>>s[0]	>>>s[3]
Output: <class ‘str’>	Output:      <class ‘str’>	Output:          <class ‘str’>	Output:’P’	Output: ’h’
>>> s=’aaa’ >>>id(s)	>>> s=’bbb’ >>>id(s)	>>>s1=”Python” >>>s1[0]	>>>s1=”Python” >>>len(s1)	>>>s1=”Python” >>>s1[-1]
Output:43695392	Output: 43175296	Output: p	Output: 6	Output: n