A First Python Program

• First Python Program:

  #!/usr/bin/python
  
  print "Hello, Python!";

• Quotation in Python:

  word = 'word'
  sentence = "This is a sentence."
  paragraph = """This is a paragraph. It is
  made up of multiple lines and sentences."""

• Comments in Python:

  #!/usr/bin/python
  
  # First comment
  print "Hello, Python!"; # second comment

• Waiting for the User:

  #!/usr/bin/python
  
  raw_input("\n\nPress the enter key to exit.")

• Multiple Statement Groups as Suites:

  if expression :
  suite
  elif expression :
  suite
  else :
  suite

• Assigning Values to Variables:

  #!/usr/bin/python
  
  counter = 100 # An integer assignment
  miles = 1000.0 # A floating point
  name = "John" # A string
  
  print counter
  print miles
  print name

• Multiple Assignment:

  a = b = c = 1
  a, b, c = 1, 2, "john"

• Python Strings:

  #!/usr/bin/python
  
  str = 'Hello World!'
  
  print str # Prints complete string
  print str[0] # Prints first character of the string
  print str[2:5] # Prints characters starting from 3rd to 5th
  print str[2:] # Prints string starting from 3rd character
  print str * 2 # Prints string two times
  print str + "TEST" # Prints concatenated string

• Python Lists:

  #!/usr/bin/python
  
  list = [ 'abcd', 786 , 2.23, 'john', 70.2 ]
  tinylist = [123, 'john']
  
  print list # Prints complete list
  print list[0] # Prints first element of the list
  print list[1:3] # Prints elements starting from 2nd till 3rd
  print list[2:] # Prints elements starting from 3rd element
  print tinylist * 2 # Prints list two times
  print list + tinylist # Prints concatenated lists

• Python Tuples:

  #!/usr/bin/python
  
  tuple = ( 'abcd', 786 , 2.23, 'john', 70.2 )
  tinytuple = (123, 'john')
  
  print tuple # Prints complete list
  print tuple[0] # Prints first element of the list
  print tuple[1:3] # Prints elements starting from 2nd till 3rd
  print tuple[2:] # Prints elements starting from 3rd element
  print tinytuple * 2 # Prints list two times
  print tuple + tinytuple # Prints concatenated lists

• Python Dictionary:

  #!/usr/bin/python
  
  dict = {}
  dict['one'] = "This is one"
  dict[2] = "This is two"
  
  tinydict = {'name': 'john','code':6734, 'dept': 'sales'}
  
  
  print dict['one'] # Prints value for 'one' key
  print dict[2] # Prints value for 2 key
  print tinydict # Prints complete dictionary
  print tinydict.keys() # Prints all the keys
  print tinydict.values() # Prints all the values