1 * Data Types

     2 *** Outline

     3 ***** Introduction

     4 ******* What are we going to do?

     5 ******* How are we going to do?

     6 ******* Arsenal Required

     7 ********* None

     8 *** Script

     9     Welcome friends. 

    10     

    11     In this tutorial we shall look at data types available in Python and 

    12     how to perform simple Input and Output operations. 

    13     for 'Numbers' we have: int, float, complex datatypes

    14     for Text content we have strings.

    15     For conditional statements, 'Booleans'.

    16     

    17     Now we shall look at Python Strings.

    18     In python anything enclosed inside quotes(single or double) is a string

    19     so 

    20     a = 'This is a string'

    21     print a

    22     b = "This too!"

    23     print b

    24     c = '''This one too!'''

    25     print c

    26     d = """And one more."""

    27     print d

    28     

    29     Similar to lists we covered earlier even string elements can be accessed 

    30     via index numbers starting from 0

    31 

    32     print a[0]    

    33     print a[5]

    34     will 

    35     To access last element we can use a[-1] which is one of Pythons feature.

    36     print a[-1]

    37     len function works with the strings also as it does with the arrays and 

    38     returns length of the string.

    39     

    40     One thing to notice about the string variables is that they are 

    41     immutable, that is

    42     a[0] = 't'

    43     will throw an error

    44     

    45     Some of methods available for string are:

    46     a.startswith('Thi')

    47     returns true if initial of the string is same

    48     similarly there is endswith

    49     a.endswith('ING')

    50     a.upper() returns a string with all letters capitalized.

    51     and a.lower() returns a string with all smaller case letters.

    52     As we have seen earlier use of split function, it returns the list after

    53     splitting the string, so

    54     a.split()

    55     will give list with three elements.

    56     we also have 'join' function, which does the opposite of what

    57     split does. 

    58     ''.join(['a','b','c']) will return a joined string of the list we pass

    59     to it. Since join is performed on '' that is empty string we get 'abc'

    60     if we do something like

    61     '-'.join(['a','b','c'])

    62     

    63     we come to the end of this tutorial on introduction of Data types in

    64     Python. In this tutorial we have learnt what are supported data types, 

    65     supported operations and performing simple IO operations in Python.

    66 

    67 *** Notes