Python Dominicana Presentation

1. Leonardo Jimenez
@leonardoajim
ljimenez@stancedata.com

2. Python for Dummies

3. Python for Dummies
Newbies

4. What is Python or What
the hell I am doing here?
- Programming Language
-Easy to Read
-Productive ( ha ha, Java programmer!!)
-Portable (.net anyone?)
-Big Library ( We got all type of wheels!)
...Fun

5. Created by Guido Van Rossum
I am in the same
picture, awesome!!
This is Guido

6. Where is python used?

7. Let's Begin
http://python.org/download/

8. Python Building Blocks
Interpreted Language
Compiler Computer

9. Python Building Blocks
A language is made by Statements
An statement is an order of what You want the
computer to do.
Examples:
Print in the screen the name of the user
Create a new windows
Calculate age
Show Image

10. Python Building Blocks
A language is made by Statements
An statement is an order of what You want the computer to do.
Examples:

11. Python Building Blocks
Variable
We have to keep track of a lot of information.
Examples:
"Engineer"
01/27/2013
example@example.com
12,0000

12. Python Building Blocks
Variable
Reserved Words.
and del from not while
as elif global or with
assert else if pass yield
break except import print
class exec in raise
finally is return continue
def for lambda try

13. Python Building Blocks
Variables

14. Python Building Blocks
Variables
title party_date email debt

15. Python Building Blocks
Variables
"Engineer" 01/27/2013
e@ex.com 12000
title party_date email debt

16. Python Building Blocks
Variables
Are Key sensitives:
myVariable != MyVariable

17. Python Building Blocks
Variables
Are Key sensitives:
myVariable != MyVariable

18. Python Building Blocks
Object
Int ex.1234 long ex. 35L float1234 35L 3.1415
bool True False
str
"Hello World" , 'simply "hello" ' """ Complex strings"""
list
dict
tuple
college = [ "awful teachers", "boring books", "some partying"]
words_said_by_women_meaning= { "best_friend" : " You lose your chance"}
(1, 'other item', 54, 'U')

19. Python Building Blocks -Int
Int ex.1234 long ex. 35L float1234 35L 3.1415
Naturals Complex
Numbers ( a + bj)
Real numbers
(a+bj)
Basic operations
+,-,*,/ , %, **
Compare
=, <, >, !=
Division by integers
Division by zero

20. Python Building Blocks -Int

21. Python Building Blocks
Test Pause
Work with Variables.py

22. Python Building Blocks -Int/LInt

23. Python Building Blocks -String

24. Python Building Blocks -String
"Hello World"
0 1 2
3
4 5 6 7
8
9 10

25. Python Building Blocks -String

26. Python Building Blocks -String
Some useful methods:
str.capitalize()
str.count(sub[, start[, end]])
str.find(sub, [,start[, end]])
str.index(sub, [,start[, end]])
str.replace(old, mes[,count])
str.lower() / str.upper()
str.join(iterable)
str.split([sep[,maxsplit]])
Pretty function
len(str)

27. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure

28. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure
training = [ ]
Training

29. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure
training = [ ]
training.append(50)
training.append(60)
training.append("Mouse")
[0]
[1]
[2]
Training
50
"Mouse"
60

30. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure
training = [ ]
training.append(50)
training.append(60)
training.append("Mouse")
[0]
[1]
[2]
Training
50
"Mouse"
60
Index

31. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure
training = [ ]
training.append(50)
training.append(60)
training.append("Mouse")
Another way of creating it is:
training = [ 50, 60, "Mouse"]
[0]
[1]
[2]
Training
50
"Mouse"
60

32. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure
training.extend([3])
[0]
[1]
[2]
[3]
Training
50
"Mouse"
60
3

33. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure
training.append(50)
[0]
[1]
[2]
[3]
[4]
Training
50
"Mouse"
60
3
50

34. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure
training.remove(50)
[0]
[1]
[2]
[3]
Training
50
"Mouse"
60
3

35. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure
training.remove(50)
[0]
[1]
[2]
[3]
Training
50
"Mouse"
60
3

36. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure
training.pop()
[0]
[1]
[2]
Training
50
"Mouse"
60
3

37. Python Building Blocks -Lists
A list if a basic structure on python, is defined as :
list = [ n1
, n2
, .... nn
] , where N is any basic python data
structure
training.pop()
[0]
[1]
[2]
Training
50
"Mouse"
60
3

38. Python Building Blocks -Lists
We treated:
list.append(x)*
list.extend(L)*
list.remove(x)*
Other Important functions:
list.insert(i, x)*
list.pop([i])*
list.count(x)*
list.sort()
list.reverse()
*Notes : x: element, i : index, l: list

39. Python Building Blocks -Lists
We treated:
list.append(x)*
list.extend(L)*
list.remove(x)*
Other Important functions:
list.insert(i, x)*
list.pop([i])*
list.count(x)*
list.sort()
list.reverse()
*Notes : x: element, i : index, l: list

40. Python Building Blocks -Tuples
Remember the lists, they are the same but You can't modify
them. They are immutable.

41. Python Building Blocks -Tuples
Remember the lists, they are the same but You
can't modify them. They are immutable.
Let's have the immutability talk!

42. Python Building Blocks -Dictionaries
Also called Hash or associative Array. Is defined as a collection
of references called keys that point to a value.
dictionary = {
'key1
' : value1
,
'key2
' : value2
,
.....................
'keyN
' : valueN
,
}

43. Python Building Blocks -Dictionaries
Also called Hash or associative Array. Is defined as a collection
of references called keys that point to a value.
dictionary = {
'key1
' : value1
,
'key2
' : value2
,
.....................
'keyN
' : valueN
,
}

44. Python Building Blocks -Dictionaries
Also called Hash or associative Array. Is defined as a collection
of references called keys that point to a value.
Key
Value

45. Python Building Blocks -Dictionaries
Also called Hash or associative Array. Is defined as a collection
of references called keys that point to a value.
You can initialize a Dictionary with the following:
d = {} #empty dictionary
d = dict()#empty dictionary
d = { "hello": "World"}
d = dict(hello="world")

46. Python Building Blocks -Dictionaries
Some Useful Dictionary methods:
len(d)
d[key]
d[key] = value
del d[key]
key in d / key not in d
d.clear()
d.has_key(key)
d.keys()
d.values()
pop(key[, default])
popitem()

47. Python Building Blocks -Other Structures
Sets
Frozensets
Files

48. Python Functions or How to be lazy with style?
1- def goes before the function you are defining. the function name can't be name of
another python defined function.
2 - It can have multiple arguments.
4- All functions must have a return value
Functions are reusable block
codes.
def function_name(argument1
, argument2
,.. .., argumentn
):
code block
return result
1 2
3
4

49. Python Functions or How to be lazy with style?
Some examples:

50. Control Structures, What If...?
Conditionals
if condition :
do something
If you have more than one option else comes handy
if condition :
do something
else:
do something else

51. Control Structures, What If...?
Conditionals
When if and else is not enough, maybe you need
elif
if condition :
do something
elif:
do something different
else:
do something else

52. Control Structures, What are you waiting for?
Conditionals
The for is one of the most used control structures
example 1:
for i in structure :
do something with i block
example 2:
for i in range(n):
do something with i block

53. Control Structures, While We wait...
Conditionals
The while is another control structure used
example 1:
variable = value
while i has condition :
do something with i block

54. Control Structures, Other things
Somethings of interest
Continue:
jumps one step
Break:
break the loop

55. List Comprehension (optional)
Somethings of interest
[ F(x) for x in object/range + conditional]
[F(x1
, x2
, ... xn
) for (x1
, x2
, ... xn
) in object/range(x1
, x2
, ... xn
) +
conditional(x1
, x2
, ... xn
)]

56. Tuple Comprehension
Somethings of interest
tuple([ F(x) for x in object/range + conditional])
tuple([F(x1
, x2
, ... xn
) for (x1
, x2
, ... xn
) in object/range(x1
, x2
, ...
xn
) + conditional(x1
, x2
, ... xn
)])

57. Tuple Comprehension
Somethings of interest
tuple([ F(x) for x in object/range + conditional])
tuple([F(x1
, x2
, ... xn
) for (x1
, x2
, ... xn
) in object/range(x1
, x2
, ...
xn
) + conditional(x1
, x2
, ... xn
)])

58. Dictionary Comprehension
Somethings of interest
{ F(x): G(x) for x in object/range + conditional}
{F(x1
, x2
, ... xn
):G(x1
, x2
, ... xn
) for (x1
, x2
, ... xn
) in object/range
(x1
, x2
, ... xn
) + conditional(x1
, x2
, ... xn
)}

59. The Files talk
The way Python interacts with files.

60. The Files examples
# Open a file
fo = open("foo.txt", "wb")
print "Name of the file: ", fo.name
print "Closed or not : ", fo.closed
print "Opening mode : ", fo.mode
print "Softspace flag : ", fo.softspace

61. The Files examples
class BankAccount(object):
def __init__(self, initial_balance=0):
self.balance = initial_balance
def deposit(self, amount):
self.balance += amount
def withdraw(self, amount):
self.balance -= amount
def overdrawn(self):
return self.balance < 0
my_account = BankAccount(15)
my_account.withdraw(5)
print my_account.balance

62. Python Building Blocks -Dir
Using "dir":
One of the most beautiful functions in
Python to study object types.

63. Looking for Help
- Exceptions
- Dir
- Documentation (help)
- Documentation (developer)
- Stackoverflow.com
- IRC
- Python Usergroup

64. Python Building Blocks -Int
dir is not clear enough, so I made a
function
Internal Attributes
Methods We care

65. Looking for Help
- Dir
- Documentation (help)
- Documentation (developer)
- Stackoverflow.com
- IRC
- Python Usergroup

66. Questions?