Angel's Blog

Python: Tricks, Fun & More.

Angel — Sun, 20 Nov 2016 02:29:31 GMT

Parsing a json string:

>>> import json
>>> 
>>> jsonString = """[
...   {"firstName":"John", "lastName":"Doe"},
...   {"firstName":"Anna", "lastName":"Smith"},
...   {"firstName":"Angel", "lastName":"Cool"}
... ]"""
>>> 
>>> 
>>> print jsonString
[
  {"firstName":"John", "lastName":"Doe"},
  {"firstName":"Anna", "lastName":"Smith"},
  {"firstName":"Angel", "lastName":"Cool"}
]
>>> 
>>> data = json.loads(jsonString)
>>> 
>>> print data[2]['firstName']
Angel
>>> print data[2]['lastName']
Cool
>>> 
>>> type(data)

>>> 
>>> 
>>> for person in data:
...     print person['firstName'] + ' ' + person['lastName']
... 
John Doe
Anna Smith
Angel Cool
>>> 
>>> data.reverse()
>>> 
>>> for person in data:
...     print person['firstName'] + ' ' + person['lastName']
... 
Angel Cool
Anna Smith
John Doe
>>>

Reversing strings:

>>> print 'Donald Trump'[::-1]
pmurT dlanoD
>>> print 'lion oil'[::-1]
lio noil
>>> print 'A car, a man, a maraca.'[::-1]
.acaram a ,nam a ,rac A

Python: Getting started with virtualenv

Angel — Sat, 19 Nov 2016 21:19:56 GMT

# install virutalenv
[aesteban@localhost ~]$ sudo pip install virtualenv

# create virtual environment
[aesteban@localhost ~]$ mkdir virt_env
[aesteban@localhost ~]$ virtualenv virt_env/virt1 --no-site-packages
New python executable in /home/aesteban/virt_env/virt1/bin/python
Installing setuptools, pip, wheel...done.
[aesteban@localhost ~]$ 

# load environment
[aesteban@localhost ~]$ source virt_env/virt1/bin/activate
(virt1) [aesteban@localhost ~]$

# deactivate environment
(virt1) [aesteban@localhost ~]$ deactivate
[aesteban@localhost ~]$ 
[aesteban@localhost ~]$ 

# listing installed packages with yolk
[aesteban@localhost ~]$ sudo pip install yolk
[aesteban@localhost ~]$ yolk -l

# installing yolk in our virutal environment
[aesteban@localhost ~]$ source virt_env/virt1/bin/activate
(virt1) [aesteban@localhost ~]$ pip install yolk
(virt1) [aesteban@localhost ~]$ yolk -l


# let's create another environment
(virt1) [aesteban@localhost ~]$ deactivate
[aesteban@localhost ~]$ virtualenv virt_env/virt2 --no-site-packages

# let's switch back to virt1 and install Pylons and SqlAlchemy
(virt1) [aesteban@localhost ~]$ pip install Pylons
...
(virt1) [aesteban@localhost ~]$ pip install SqlAlchemy

# compare virt1 and virt2 using: yolk -l

Big shout-out to:
http://www.simononsoftware.com/virtualenv-tutorial/

Thank you guys!

Python 101: Learning by doing.

Angel — Tue, 27 Oct 2015 22:51:32 GMT

Looping through a dictionary (aka map):

Python 2.7.5

>>> map = {50+i:i for i in range(10)}
>>> map
{50: 0, 51: 1, 52: 2, 53: 3, 54: 4, 55: 5, 56: 6, 57: 7, 58: 8, 59: 9}
>>> for key, value in map.iteritems():
...     print key,'-',value
... 
50 - 0
51 - 1
52 - 2
53 - 3
54 - 4
55 - 5
56 - 6
57 - 7
58 - 8
59 - 9
>>>

Python 3.3.2

>>> map = {50+i:i for i in range(10)}
>>> map
{50: 0, 51: 1, 52: 2, 53: 3, 54: 4, 55: 5, 56: 6, 57: 7, 58: 8, 59: 9}
>>> for key, value in map.items():
...  print(key,' - ',value)
... 
50  -  0
51  -  1
52  -  2
53  -  3
54  -  4
55  -  5
56  -  6
57  -  7
58  -  8
59  -  9
>>>

Fetching url data:

Python 2

[aesteban@localhost corpemployees-filtered]$ python
Python 2.7.5 (default, Apr 10 2015, 08:09:05) 
[GCC 4.8.3 20140911 (Red Hat 4.8.3-7)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> 
>>> import urllib
>>> urllib.urlopen('https://graph.facebook.com/?id=http://www.barney.com').read()
'{"id":"http:\\/\\/www.barney.com","shares":792}'

Python 3

[aesteban@localhost corpemployees-filtered]$ python3
Python 3.3.2 (default, Dec  4 2014, 12:49:00) 
[GCC 4.8.3 20140911 (Red Hat 4.8.3-7)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> 
>>> import urllib.request
>>> 
>>> urllib.request.urlopen('https://graph.facebook.com/?id=http://www.barney.com').read()
b'{"id":"http:\\/\\/www.barney.com","shares":792}'