Python Looping Techniques

looping thru list

li = ['cube', 'sphere', 'reactangle' ]

for i, v in enumerate(li):
    print i,v

0 cube
1 sphere
2 reactangle

Looping thru Dictionary

a = {'translate': '25', 'rotate': '4'} 

for k, v in a.iteritems():
     print k, v

translate 25
rotate 4

List Comprehension

squares = [x**2 for x in range(10)]

 [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

squares = map(lambda x: x**2, range(10))

 [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

Python: list objects to string

Python tips - How to easily convert a list to a string for display

if it is a list of strings, you may simply use join this way:

>>> mylist = ['spam', 'ham', 'eggs']
>>> print ', '.join(mylist)
spam, ham, eggs 

Using the same method, you might also do this:

>>> print '\n'.join(mylist) spam ham eggs

spam
ham
eggs

u can store the result in string variable. this time its and empty space between list objects 

 >>> c =  ' '.join(mylist)

spam ham eggs  

for non-string objects, such as integers.

If you just want to obtain a comma-separated string, you may use this shortcut:

>>> list_of_ints = [820, 547, 8080, 8081] 
>>> print str(list_of_ints).strip('[]') 

820, 547, 8080, 8081 

Or this one, if your objects contain square brackets:

>>> print str(list_of_ints)[1:-1] 

820, 547, 8080, 8081 

Finally, you may use map() to convert each item in the list to a string, and then join them:

>>> print ', '.join(map(str, list_of_ints)) 
820, 547, 8080, 8081 
>>> print '\n'.join(map(str, list_of_ints)) 

820 547 8080 8081