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Let’s Learn PythonAn introduction to Python       Jaganadh G Project Lead NLP R&D   365Media Pvt. Ltd.  jaganadhg@gmail.co...
Just a word about me !!    Working in Natural Language Processing (NLP), Machine    Learning, Data Mining    Passionate ab...
Python    Python is an easy to learn, powerful programming    language.    It has efficient high-level data structures and a...
Features of Python    Simple      1   Python is a simple and minimalist language      2   Reading a good Python program fe...
Features of Python    Interpreted    Object Oriented    Extensible    Embeddable    Batteries included                    ...
Installing Python    If you are using a Linux distribution such as Fedora or    Ubuntu then you probably already have Pyth...
Hello world !!!     Lets write a ”Hello world!!” program     Fire-up the terminal and invoke Python interpreter     Type p...
Hello world !!! #!/usr/bin/env python #Just a Hello World !! program print "Hello World!!"     You can write the code in y...
Using the Python Interpreter    The Python iterpreter can be used as a calculator !!                     Jaganadh G   Let’...
Keywords     The following are keywords or reserved words in Python     These words can’t be used as variable names or fun...
Variables age = 32 year = 1997 avg = 12.5 Note: There is no need to specify the type as like in C or Java                 ...
String name = ”jagan” anname = ’jagan’ annname = ”””jagan””” Note: There is no need to specify the type as like in C or Ja...
Identifier Naming    Identifiers    Identifiers are names given to identify something.    Rules to follow for naming identifie...
Operators             +          Plus             -        Minus             /         divide             *       Multiply...
Basic Math                     !=      Not equal to                     not     Boolian NOT                     and     Bo...
Data Structure: List    A list is a data structure that holds an ordered collection    of items    fruits = [’apple’,’bana...
Data Structure: List    elemnts can be accessed by index numbers    fruits[0]    elements can be accessed with positive or...
Data Structure: List    elements can be deleted del fruits[0]    list can be sliced new list = fruits[1:3]    lists can be...
Data Structure: List    The pop method removes an element from a list    fruits.pop()    The remove method is used to remo...
Data Structure: List >>> numbers = [5, 2, 9, 7] >>> numbers.sort(cmp) >>> numbers [2, 5, 7, 9] >>> x = [’aardvark’, ’abalo...
Data Structure: Tuple    Tuples are sequences like lists .    The only difference is that tuples are immutable    Values in...
Data Structure: Tuple     There is a way to sort and reverse tuple     atuple = (9,6,4,8,3,7,2)     sortuple = tuple(sorte...
Data Structure: Dictionary    Another useful data type built into Python is the    dictionary    Dictionaries are sometime...
Basic Dictionary Operations    len(d) returns the number of items (key-value pairs) in d    d = {’Alice’: ’2341’, ’Beth’: ...
Data Structure: Dictionary    Key types: Dictionary keys dont have to be integers    (though they may be). They may be any...
Data Structure: Dictionary    All the keys in a dictionary can be accessed as a list    phonebook.keys()    [’Beth’, ’Alic...
Control Flow:The if statement The if statement is used to check a condition and if the condition is true, we run a block o...
Control Flow:The if statement    name = raw_input(""Enter your name: "")    if name == "trisha":       print "Hi trisha ha...
Control Flow:The while statement The while statement allows you to repeatedly execute a block of statements as long as a c...
Control Flow:The while statement #!/usr/bin/python a = 0 b = 10 while a < b:   print a   a += 1 #0123456789               ...
Control Flow:The for loop The for..in statement is another looping statement which iterates over a sequence of objects i.e...
Control Flow:The for loop #!/usr/bin/python names = [’Jaganadh’,’Biju’,’Sreejith’, ’Kenneth’,’Sundaram’] for name in names...
Control Flow:The for loop #!/usr/bin/python for i in range(1, 5):   print i else:   print ’The for loop is over’          ...
Control Flow: The break,continue and passstatement The break statement is used to break out of a loop statement i.e. stop ...
Control Flow: continue    #Example for continue    x = 10    while x:       x = x -1       if x % 2 != 0: continue       p...
Control Flow:break #Example for break while True:   s = raw_input(’Enter something : ’)     if s == ’quit’:       break   ...
Control Flow:pass  #Example for pass   while 1:     pass                  Jaganadh G   Let’s Learn Python
Functions Functions are reusable pieces of programs. They allow you to give a name to a block of statements and you can ru...
Functions with parameters A function can take parameters which are just values you supply to the function so that the func...
Functions: Using Keyword Arguments #!/usr/bin/python # Filename: func_key.py def func(a, b=5, c=10):   print ’a is’, a, ’a...
Functions: Return Statement #!/usr/bin/python # Filename: func_return.py def maximum(x, y):   if x > y:     return x   els...
Functions: Arbitrary Arguments def minimum(*args):   res = args[0]     for arg in args[1:]:       if arg < res: res = arg ...
Functions: Arbitrary Arguments def arbArg(**args):     print args print arbArg(a=1,b=2,c=6) #{’a’: 1, ’c’: 6, ’b’: 2}     ...
Object Oriented Programming #!/usr/bin/python # Filename: simplestclass.py class Person:   pass # An empty block p = Perso...
Object Oriented Programming:Using ObjectMethods Class/objects can have methods just like functions except that we have an ...
Object Oriented Programming:The                          initmethod The init method is run as soon as an object of a class...
Object Oriented Programming:Class andObject Variables There are two types of fields - class variables and object variables ...
Object Oriented Programming:Class andObject Variables #!/usr/bin/python # Filename: objvar.py class Person:   ’’’Represent...
Object Oriented Programming:Class andObject Variables    def __del__(self):      ’’’I am dying.’’’      print ’%s says bye...
Object Oriented Programming:Class andObject Variables   def howMany(self):     ’’’Prints the current population.’’’     if...
Object Oriented Programming: Inheritance #!/usr/bin/python # Filename: inherit.py class SchoolMember:   ’’’Represents any ...
Object Oriented Programming: Inheritance class Teacher(SchoolMember):   ’’’Represents a teacher.’’’   def __init__(self, n...
Object Oriented Programming: Inheritance class Student(SchoolMember):   ’’’Represents a student.’’’   def __init__(self, n...
Modules A module is basically a file containing all your functions and variables that you have defined. To reuse the module ...
I/O Operations #File reading myfile = open("help.txt",’r’) filetext = myfile.read() myfile.close() #file reading 2 myfile ...
I/O Operations with open(help.txt, r) as f:   read_data = f.read() #file writing out = open(’out.txt’,’w’) out.write("Hell...
Handling Exceptions while True:   try:     x = int(raw_input("Please enter a number: "))     break   except ValueError:   ...
Handling Exceptions import sys try:   f = open(myfile.txt)   s = f.readline()   i = int(s.strip()) except IOError as (errn...
Questions ??               Jaganadh G   Let’s Learn Python
Where can I post questions?    Search in the net . If nothing found    Post in forums    ILUGCBE http://ilugcbe.techstud.o...
References    A Byte of Python : Swaroop CH    Dive in to Python    Many wikibooks .............                   Jaganad...
Finally          Jaganadh G   Let’s Learn Python
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Let’s Learn Python An introduction to Python

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Let’s Learn Python
An introduction to Python

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  1. 1. Let’s Learn PythonAn introduction to Python Jaganadh G Project Lead NLP R&D 365Media Pvt. Ltd. jaganadhg@gmail.com KiTE, Coimbatore 19 July 2011 Jaganadh G Let’s Learn Python
  2. 2. Just a word about me !! Working in Natural Language Processing (NLP), Machine Learning, Data Mining Passionate about Free and Open source :-) When gets free time teaches Python and blogs at http://jaganadhg.freeflux.net/blog reviews books for Packt Publishers. Works for 365Media Pvt. Ltd. Coimbatore India. Member of Indian Python Software Society Jaganadh G Let’s Learn Python
  3. 3. Python Python is an easy to learn, powerful programming language. It has efficient high-level data structures and a simple but effective approach to object-oriented programming. Elegant syntax Dynamic typing Interpreted Ideal for scripting and rapid application development Developed by Guido Van Rossum Free and Open Source Jaganadh G Let’s Learn Python
  4. 4. Features of Python Simple 1 Python is a simple and minimalist language 2 Reading a good Python program feels almost like reading English Easy to Learn 1 Python is extremely easy to get started with 2 Python has an extraordinarily simple syntax Free and Open Source High-level Language Portable, You can use Python on 1 Linux 2 Microsoft Windows 3 Macintosh 4 ........... Jaganadh G Let’s Learn Python
  5. 5. Features of Python Interpreted Object Oriented Extensible Embeddable Batteries included Jaganadh G Let’s Learn Python
  6. 6. Installing Python If you are using a Linux distribution such as Fedora or Ubuntu then you probably already have Python installed on your system. To test it open a shell program like gnome-terminal or konsole and enter the command python -V If you are using windows - go to http://www.python.org/download/releases/2.7/ and download http://www.python.org/ftp/python/2.7/python-2.7.msi. Then double click and install it. You may need to set PATH variable in Environment Settings Jaganadh G Let’s Learn Python
  7. 7. Hello world !!! Lets write a ”Hello world!!” program Fire-up the terminal and invoke Python interpreter Type print ”Hello World !!! ” Jaganadh G Let’s Learn Python
  8. 8. Hello world !!! #!/usr/bin/env python #Just a Hello World !! program print "Hello World!!" You can write the code in you favorite editor, save and run it. Extension for the filename should be .py Save it as hello.py and make it as executable ! #chmod +x hello.py Run the program #python hello.py Jaganadh G Let’s Learn Python
  9. 9. Using the Python Interpreter The Python iterpreter can be used as a calculator !! Jaganadh G Let’s Learn Python
  10. 10. Keywords The following are keywords or reserved words in Python These words can’t be used as variable names or function names or class names and del for is raise assert elif from lambda return break else global not try class except if or while continue exec import pass yield def finally in print Jaganadh G Let’s Learn Python
  11. 11. Variables age = 32 year = 1997 avg = 12.5 Note: There is no need to specify the type as like in C or Java Jaganadh G Let’s Learn Python
  12. 12. String name = ”jagan” anname = ’jagan’ annname = ”””jagan””” Note: There is no need to specify the type as like in C or Java Jaganadh G Let’s Learn Python
  13. 13. Identifier Naming Identifiers Identifiers are names given to identify something. Rules to follow for naming identifiers 1 The first character of the identifier must be a letter of the alphabet (upper or lowercase) or an underscore (’ ’). 2 The rest of the identifier name can consist of letters (upper or lowercase), underscores (’ ’) or digits (0-9). 3 Identifier names are case-sensitive. For example, myname andmyName are not the same. Note the lowercase n in the former and the uppercaseN in te latter. 4 Examples of valid identifier names arei, my name, name 23 and a1b c3 . 5 Examples of invalid identifier names are 2things, this is spaced out and my-name. Jaganadh G Let’s Learn Python
  14. 14. Operators + Plus - Minus / divide * Multiply ** Power // Floor Division % Modulo < Less than > Greater than <= Less than or equal to >= Greater than equal to == Equal to Jaganadh G Let’s Learn Python
  15. 15. Basic Math != Not equal to not Boolian NOT and Boolian AND or Boolian OR & Bitwise AND Note: Operator precedence is as same as of other programming languages Jaganadh G Let’s Learn Python
  16. 16. Data Structure: List A list is a data structure that holds an ordered collection of items fruits = [’apple’,’banana’,’orange’] marks = [12,15,17] avgs = [1.5, 4.5,7.8] avgm = [1.5, 4.5,7.8,avgs] lists are mutable elemnts can be accessed by index numbers either positive index or negative index can be used to access elements Jaganadh G Let’s Learn Python
  17. 17. Data Structure: List elemnts can be accessed by index numbers fruits[0] elements can be accessed with positive or negative index avgs[-1] new elements can be appended to a list fruits.append(’cherry’) list can be sorted or reversed fruits.sort() fruits.reverse() length of a list can be identified by the ’len’ function len(fruits) Jaganadh G Let’s Learn Python
  18. 18. Data Structure: List elements can be deleted del fruits[0] list can be sliced new list = fruits[1:3] lists can be extended flowers = [’rose’,’lilly’,’tulip’] fruits.extend(flowers) the index method can be used to find index of an item in a list fruits.index(’apple’) Jaganadh G Let’s Learn Python
  19. 19. Data Structure: List The pop method removes an element from a list fruits.pop() The remove method is used to remove the first occurrence of a value: flowers = [’rose’,’lilly’,’tulip’,’rose’] flowers.remove(’rose’) The reverse method reverses the elements in the list. flowers.reverse() The sort method is used to sort lists in place flowers.sort() Jaganadh G Let’s Learn Python
  20. 20. Data Structure: List >>> numbers = [5, 2, 9, 7] >>> numbers.sort(cmp) >>> numbers [2, 5, 7, 9] >>> x = [’aardvark’, ’abalone’, ’acme’, ’add’, ’aerate’] >>> x.sort(key=len) >>> x [’add’, ’acme’, ’aerate’, ’abalone’, ’aardvark’] >>> x = [4, 6, 2, 1, 7, 9] >>> x.sort(reverse=True) Jaganadh G Let’s Learn Python
  21. 21. Data Structure: Tuple Tuples are sequences like lists . The only difference is that tuples are immutable Values in a tuple are enclosed in parentheses (()) mytuple = (2,3,4,5,6,7,8) Elements in a tuple can be accessed by index value It is not possible to sort or reverse tuple Jaganadh G Let’s Learn Python
  22. 22. Data Structure: Tuple There is a way to sort and reverse tuple atuple = (9,6,4,8,3,7,2) sortuple = tuple(sorted(atuple)) revtuple = tuple((reversed(atuple)) Note: A tuple can be converted to list and vice versa tup = (1,2,3) li = list(tup) atup = tuple(li) Jaganadh G Let’s Learn Python
  23. 23. Data Structure: Dictionary Another useful data type built into Python is the dictionary Dictionaries are sometimes found in other languages as associative memories or associative arrays. Dictionaries consist of pairs (called items) of keys and their corresponding values phonebook = {’Alice’: ’2341’, ’Beth’: ’9102’, ’Cecil’: ’3258’} phonebook[’Alice’] #’2341’ Jaganadh G Let’s Learn Python
  24. 24. Basic Dictionary Operations len(d) returns the number of items (key-value pairs) in d d = {’Alice’: ’2341’, ’Beth’: ’9102’, ’Cecil’: ’325 len(d) 3 d[’Alice’] returns the value associated with the key k ie ”2341” d[’Alice’] = ’456’ associates the value ’456’ with the key ’Alice’ del d[’Alice’] deletes the item with key ’Alice’ ’Alice’ in d checks whether there is an item in d that has the key ’Alice’ Jaganadh G Let’s Learn Python
  25. 25. Data Structure: Dictionary Key types: Dictionary keys dont have to be integers (though they may be). They may be any immutable type, such as floating-point (real) numbers, strings, or tuples. Automatic addition: You can assign a value to a key, even if that key isnt in the dictionary to begin with; in that case, a new item will be created. You cannot assign a value to an index outside the lists range (without using append or something like that). phonebook[’Ravi’] = ’567’ Membership: The expression k in d (where d is a dictionary) looks for a key, not a value. ’Alice’ in phonebook Jaganadh G Let’s Learn Python
  26. 26. Data Structure: Dictionary All the keys in a dictionary can be accessed as a list phonebook.keys() [’Beth’, ’Alice’, ’Cecil’] All the values in a dictionary can be accessed as a list phonebook.values() [’9102’, ’2341’, ’3258’] The keys and values in a dictionary can be accessed as a list of tuples phonebook.items() [(’Beth’, ’9102’), (’Alice’, ’2341’), (’Cecil’, ’3258’)] Jaganadh G Let’s Learn Python
  27. 27. Control Flow:The if statement The if statement is used to check a condition and if the condition is true, we run a block of statements (called the if-block), else we process another block of statements (called the else-block). The else clause is optional. if <test1>: #if test <statement1> #associated block elif <test2>: # Optional else if (elif) <statement2> else: #optional else <statement3> Jaganadh G Let’s Learn Python
  28. 28. Control Flow:The if statement name = raw_input(""Enter your name: "") if name == "trisha": print "Hi trisha have you seen my chitti" elif name == "aishwarya": print "Hai Aishu have u seen my chitti" else: print "Oh!! my chitti !!!!" Jaganadh G Let’s Learn Python
  29. 29. Control Flow:The while statement The while statement allows you to repeatedly execute a block of statements as long as a condition is true. A while statement is an example of what is called a looping statement. A while statement can have an optional else clause.The structure of while loop is while <test>: <statement> else: <statement> Jaganadh G Let’s Learn Python
  30. 30. Control Flow:The while statement #!/usr/bin/python a = 0 b = 10 while a < b: print a a += 1 #0123456789 Jaganadh G Let’s Learn Python
  31. 31. Control Flow:The for loop The for..in statement is another looping statement which iterates over a sequence of objects i.e. go through each item in a sequence. for <target> in <object>: <statement> else: statement Jaganadh G Let’s Learn Python
  32. 32. Control Flow:The for loop #!/usr/bin/python names = [’Jaganadh’,’Biju’,’Sreejith’, ’Kenneth’,’Sundaram’] for name in names: print "Hello %s" %name Jaganadh G Let’s Learn Python
  33. 33. Control Flow:The for loop #!/usr/bin/python for i in range(1, 5): print i else: print ’The for loop is over’ Jaganadh G Let’s Learn Python
  34. 34. Control Flow: The break,continue and passstatement The break statement is used to break out of a loop statement i.e. stop the execution of a looping state-ment, even if the loop condition has not become False or the sequence of items has been completely iterated over. while <test1>: <statement> if <test1>:break else <test2>:continue else: <statement> Jaganadh G Let’s Learn Python
  35. 35. Control Flow: continue #Example for continue x = 10 while x: x = x -1 if x % 2 != 0: continue print x Jaganadh G Let’s Learn Python
  36. 36. Control Flow:break #Example for break while True: s = raw_input(’Enter something : ’) if s == ’quit’: break print ’Length of the string is’, len(s) print ’Done’ Jaganadh G Let’s Learn Python
  37. 37. Control Flow:pass #Example for pass while 1: pass Jaganadh G Let’s Learn Python
  38. 38. Functions Functions are reusable pieces of programs. They allow you to give a name to a block of statements and you can run that block using that name anywhere in your program and any number of times. This is known as calling the function. Defining Functions def <name>(arg1,arg2,...argN): <statement> #!/usr/bin/python # Filename: function1.py def sayHello(): print ’Hello World!’ # End of function sayHello() # call the function Jaganadh G Let’s Learn Python
  39. 39. Functions with parameters A function can take parameters which are just values you supply to the function so that the function can do something utilising those values. #!/usr/bin/python # Filename: func_param.py def printMax(a, b): if a > b: print a, ’is maximum’ else: print b, ’is maximum’ printMax(3, 4) # directly give literal values x = 5 y = 7 printMax(x, y) Jaganadh G Let’s Learn Python
  40. 40. Functions: Using Keyword Arguments #!/usr/bin/python # Filename: func_key.py def func(a, b=5, c=10): print ’a is’, a, ’and b is’, b, ’and c is’, c func(3, 7) func(25, c=24) func(c=50, a=100) Jaganadh G Let’s Learn Python
  41. 41. Functions: Return Statement #!/usr/bin/python # Filename: func_return.py def maximum(x, y): if x > y: return x else: return y print maximum(2, 3) Jaganadh G Let’s Learn Python
  42. 42. Functions: Arbitrary Arguments def minimum(*args): res = args[0] for arg in args[1:]: if arg < res: res = arg return res print minimum(3,4,1,2,5) Jaganadh G Let’s Learn Python
  43. 43. Functions: Arbitrary Arguments def arbArg(**args): print args print arbArg(a=1,b=2,c=6) #{’a’: 1, ’c’: 6, ’b’: 2} Jaganadh G Let’s Learn Python
  44. 44. Object Oriented Programming #!/usr/bin/python # Filename: simplestclass.py class Person: pass # An empty block p = Person() print p Jaganadh G Let’s Learn Python
  45. 45. Object Oriented Programming:Using ObjectMethods Class/objects can have methods just like functions except that we have an extra self variable. class Person: def sayHi(self): print ’Hello, how are you?’ p = Person() p.sayHi() Jaganadh G Let’s Learn Python
  46. 46. Object Oriented Programming:The initmethod The init method is run as soon as an object of a class is instantiated. The method is useful to do any initialization you want to do with your object. Notice the double underscore both in the beginning and at the end in the name. #!/usr/bin/python # Filename: class_init.py class Person: def __init__(self, name): self.name = name def sayHi(self): print ’Hello, my name is’, self.name p = Person(’Jaganadh G’) p.sayHi() Jaganadh G Let’s Learn Python
  47. 47. Object Oriented Programming:Class andObject Variables There are two types of fields - class variables and object variables which are classified depending on whether the class or the object owns the variables respectively. Class variables are shared in the sense that they are accessed by all objects (instances) of that class.There is only copy of the class variable and when any one object makes a change to a class variable, the change is reflected in all the other instances as well. Object variables are owned by each individual object/instance of the class. In this case, each object has its own copy of the field i.e. they are not shared and are not related in any way to the field by the samen name in a different instance of the same class. Jaganadh G Let’s Learn Python
  48. 48. Object Oriented Programming:Class andObject Variables #!/usr/bin/python # Filename: objvar.py class Person: ’’’Represents a person.’’’ population = 0 def __init__(self, name): ’’’Initializes the person’s data.’’’ self.name = name print ’(Initializing %s)’ % self.name Person.population += 1 Jaganadh G Let’s Learn Python
  49. 49. Object Oriented Programming:Class andObject Variables def __del__(self): ’’’I am dying.’’’ print ’%s says bye.’ % self.name Person.population -= 1 if Person.population == 0: print ’I am the last one.’ else: print ’There are still %d people left.’ % Person.population def sayHi(self): ’’’Greeting by the person. Really, that’s all it does.’’’ print ’Hi, my name is %s.’ % self.name Jaganadh G Let’s Learn Python
  50. 50. Object Oriented Programming:Class andObject Variables def howMany(self): ’’’Prints the current population.’’’ if Person.population == 1: print ’I am the only person here.’ else: print ’We have %d persons here.’ % Person.population swaroop = Person(’Swaroop’) swaroop.sayHi() swaroop.howMany() kalam = Person(’Abdul Kalam’) kalam.sayHi() kalam.howMany() Jaganadh G Let’s Learn Python
  51. 51. Object Oriented Programming: Inheritance #!/usr/bin/python # Filename: inherit.py class SchoolMember: ’’’Represents any school member.’’’ def __init__(self, name, age): self.name = name self.age = age print ’(Initialized SchoolMember: %s)’ % self.name def tell(self): ’’’Tell my details.’’’ print ’Name:"%s" Age:"%s"’ % (self.name, self.age), Jaganadh G Let’s Learn Python
  52. 52. Object Oriented Programming: Inheritance class Teacher(SchoolMember): ’’’Represents a teacher.’’’ def __init__(self, name, age, salary): SchoolMember.__init__(self, name, age) self.salary = salary print ’(Initialized Teacher: %s)’ % self.name def tell(self): SchoolMember.tell(self) print ’Salary: "%d"’ % self.salary Jaganadh G Let’s Learn Python
  53. 53. Object Oriented Programming: Inheritance class Student(SchoolMember): ’’’Represents a student.’’’ def __init__(self, name, age, marks): SchoolMember.__init__(self, name, age) self.marks = marks print ’(Initialized Student: %s)’ % self.name def tell(self): SchoolMember.tell(self) print ’Marks: "%d"’ % self.marks t = Teacher(’Mrs. Shrividya’, 40, 30000) s = Student(’Swaroop’, 22, 75) members = [t, s] for member in members: member.tell() Jaganadh G Let’s Learn Python
  54. 54. Modules A module is basically a file containing all your functions and variables that you have defined. To reuse the module in other programs, the filename of the module must have a .py extension. By using the import statement you can use built-in modules in Python import sys , os sys.argv[1] os.name os.curdir import math math.sqrt(9) Jaganadh G Let’s Learn Python
  55. 55. I/O Operations #File reading myfile = open("help.txt",’r’) filetext = myfile.read() myfile.close() #file reading 2 myfile = open("help.txt",’r’) filetext = myfile.readlines() myfile.close() Jaganadh G Let’s Learn Python
  56. 56. I/O Operations with open(help.txt, r) as f: read_data = f.read() #file writing out = open(’out.txt’,’w’) out.write("Hello out file") out.close() Jaganadh G Let’s Learn Python
  57. 57. Handling Exceptions while True: try: x = int(raw_input("Please enter a number: ")) break except ValueError: print "Oops! That was no valid number.Try again" Jaganadh G Let’s Learn Python
  58. 58. Handling Exceptions import sys try: f = open(myfile.txt) s = f.readline() i = int(s.strip()) except IOError as (errno, strerror): print "I/O error({0}): {1}".format(errno, strerror) except ValueError: print "Could not convert data to an integer." except: print "Unexpected error:", sys.exc_info()[0] raise Jaganadh G Let’s Learn Python
  59. 59. Questions ?? Jaganadh G Let’s Learn Python
  60. 60. Where can I post questions? Search in the net . If nothing found Post in forums ILUGCBE http://ilugcbe.techstud.org Jaganadh G Let’s Learn Python
  61. 61. References A Byte of Python : Swaroop CH Dive in to Python Many wikibooks ............. Jaganadh G Let’s Learn Python
  62. 62. Finally Jaganadh G Let’s Learn Python
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