Tuesday, October 22, 2013

Python

Python is an interpreted and Object oriented language.

Variable is simply defined as:
my_int=7
my_float=1.23
my_bool=True
my_string = "Always look on the bright side of life!"

Never use quotation marks (' or ") with booleans, and always capitalize the first letter! Python is case-sensitive (it cares about capitalization). 

In Python, statements are separated by whitespace (no ; at the end!).

Code needs to be indented by 4 spaces (or a tab).
Ex:
def spam():
    eggs = 12
    return eggs

Comments begin with # or use triple quotation marks for a multi-line comment.
Ex:
""" Hi there 
this is my comment

Long one indeed!"""

Arithmetic operators: +, -, *, /, % and ** (Exponentiation). The ** operator raises the first number, the base, to the power of the second number, theexponent.
Ex:
my_var = 10**2
Ans: 100

Backslash (\) escapes a string with quotes.
Ex:
'Help! Help! I\'m being repressed!'

So if you wanted "Y", you could just type "PYTHON"[1].

String methods: string methods are pre-built pieces of code that perform specific tasks for strings. They are: len(), lower(), upper() and str()
Ex:
print "The value of pi is around " + str(3.14)
+ works as string concat operator but first we need to convert 3.14 (a float) to string using str()

print "The %s who %s %s!" % ("Knights", "say", "Ni")

Getting user input on Console:
name = raw_input("What is your name?")


Using datetime:
from datetime import datetime

now = datetime.now()
print str(now.month) + "/" + str(now.day) + "/" + str(now.year)



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