1. Introduction to Python

2. Outline Python IS ……. History Installation Data Structures Flow of Control Functions Modules References

3. Python IS …..  Interpreted  Like pseudo code, hence development-friendly  Intuitive, easy to learn, understandable  White-space sensitive; acts as delimiter  Portable  Extensive standard libraries  Compatible with other languages  It is OPEN source

4. History  Invented in 1990 by Guido Van Rossum  The name ‘Python’ stems from "Monty Python's Flying Circus“  Currently, he works for Google (since 2005). He wrote a web based code review tool for Google in Python.

5. Installation  Available for FREE online  IDLE is a known editor $cmd> python // opens the console >> print “hello” hello >> import “filename” ….

6. Data Structures  Variables - need not be declared  String - comes with usual string manipulations “hello” + “123” – gives  “hello123” // Concat “Hello”*3 – gives  “HelloHelloHello” // Repetition len(“array_name”) – gives  10  Lists list = [‘a’, ’b’, ’c’] Dynamic array Items can be of any type Indexed basedprint list[0] // prints ‘a’ Operations such as append(), insert(), pop(), reverse(), sort()‏

7.  Dictionary Map of keys and values E.g. dictionary = {“key1:value1”, “key2:value2”, …..} Operations such as insert, delete, has_key(), keys(), values(), …. Example >> Polygons = {“triangle:3”, “rectangle:4”, “pentagon:5”} >> print Polygons[“triangle”] 3

8.  References Address to the object referred Pointer_a = Pointer_b // doesn’t copy value  Both now point to same object  >> Pointer_a = [1,2]  >> Pointer_b = Pointer_a  >> Pointer_a.append(3)‏  >> print b  [1,2,3]

9.  Tuples Consists of values separated by commas  E.g. >> tuple = “12”, “abc”, 890  >> tuple[0]  12 Nesting allowed  T = ((“1”, “abc”, 1234), (“2”, “pqr”, 5678))‏ Acts like a DB Tuples are immutable x,y,z = T // unpacking Special case for tuple with 0 or 1 items  >> empty = ()// 0 items  >> single = (‘123’,)// trailing comma

10. Flow of Control (no braces)‏ If (condition): statement 1// Mark the indentation statement 2// Grouping else: statement1 while(condition): statement for var in seq: statement

11.  break  Continue Functions  def name(arg1, arg2,….): statement… return // optional Example: def sum(num1, num2): return (num1 + num2)‏

12. Modules/Scripts:  File containing statements and functions  Comes with “.py” suffix  Invoked by “import filename” Object-oriented

13. References:  Python Homepage http://www.python.org  Python Tutorial http://www.python.org/tut  Python Documentation http://www.python.org/doc