.. Objectives

.. ----------

.. At the end of this tutorial, you should know --

..   1. How to define strings

..   #. Different ways of defining a string

..   #. How to concatenate strings 

..   #. How to print a string repeatedly 

..   #. Accessing individual elements of the string

..   #. Immutability of strings

.. Prerequisites

.. -------------

.. 1. getting started with ipython

.. Author              : Madhu

   Internal Reviewer   : 

   External Reviewer   :

   Checklist OK?       : <put date stamp here, if OK> [2010-10-05]

Script

------

{{{ Show the slide containing the title }}}

Hello friends. Welcome to this spoken tutorial on Getting started with

strings.

{{{ Show the slide containing the outline }}}

{{{ Shift to terminal and start ipython }}}

To begin with let us start ipython, by typing::

  ipython

on the terminal

or double quotes or triple single quotes or triple double quotes are

{{{ Type in ipython the following and read them as you type }}}::

  'This is a string'

  "This is a string too'

  '''This is a string as well'''

  """This is also a string"""

  'p'

  "Python's string manipulation functions are very useful"

using any escaping. Everything within the triple quotes is a single

string no matter how many lines it extends::

   """Having more than one control character to define

   strings come as very handy when one of the control

   characters itself is part of the string."""

We can assign this string to any variable::

  a = 'Hello, World!'

Now 'a' is a string variable. String is a collection of characters. In

addition string is an immutable collection. So all the operations that

are applicable to any other immutable collection in Python works on

string as well. So we can add two strings::

  a = 'Hello'

  b = 'World'

  c = a + ', ' + b + '!'

We can add string variables as well as the strings themselves all in

the same statement. The addition operation performs the concatenation

of two strings.

Similarly we can multiply a string with an integer::

  a = 'Hello'

  a * 5

gives another string in which the original string 'Hello' is repeated

5 times.

  a[0]

gives us the first character in the string. The indexing starts from 0

gives us second element from the end of the string

Let us attempt to change one of the characters in a string::

  a = 'hello'

  a[0] = 'H'

As said earlier, strings are immutable. We cannot manipulate the

string. Although there are some methods which let us to manipulate the

strings. We will look at them in the advanced session on strings. In

addition to the methods that let us manipulate the strings we have

methods like split which lets us break the string on the specified

separator, the join method which lets us combine the list of strings

into a single string based on the specified separator.

{{{ Show summary slide }}}

This brings us to the end of another session. In this tutorial session

we learnt

  * How to define strings

  * Different ways of defining a string

  * Accessing individual elements of the string

  * Immutability of strings

{{{ Show the "sponsored by FOSSEE" slide }}}

This tutorial was created as a part of FOSSEE project, NME ICT, MHRD India

Hope you have enjoyed and found it useful.

Thank you!