View source for Python quick reference

==Introduction==
==Lexical analysis==
==Data model==
==Execution model==
==Expressions==
==Simple statements==
===variable operations===
'''assigenment examples'''

====simple string assignment====
<source lang="python">
 >>> var1 = 'foo'
</source>

this automatically creates a variable of type string

 >>> type(var1)
 <type 'str'>

printing your variable...

<source lang="python">
 >>> print var1
 foo
</source>

string assignment like above must be incapsulated by quotes or the right side is interpretted as a variable name.

example:

 >>> var1 = foo
 Traceback (most recent call last):
 File "<stdin>", line 1, in ?
 NameError: name 'foo' is not defined

====integer variable====

<source lang="python">
>>> my_int_var1 = 1
>>> print my_int_var1
1
</source>

====assigning a variable to another variable====

<source lang="python">
>>> var2 = 'bar'
>>> var1 = var2
>>> print var1
bar
</source>

muli-variable example:

<source lang="python">
>>> var1 = 'foo'
>>> var2 = 'bar'
>>> new_var = "%s %s" % (var1,var2)
>>> print new_var
foo bar
</source>

===print===

print sing variable named foo
<source lang="python">
>>> print foo
</source>

print variables with text
<source lang="python">
print 'my variable is %s' % FOO
</source>
or
<source lang="python">
print 'my variable are %s %s' % (FOO, BAR)
</source>

print without a newline, use comma at the end of the print statement
<source lang="python">
for i in range(10):
...     print i,
... else:
...     print
...
0 1 2 3 4 5 6 7 8 9
</source>

==Common string operations==

print nth word of string
<source lang="python">
 print s.split()[n]
</source>

<source lang="python">
str = "this is string example....wow!!!"
print (str.split( ))
print (str.split('i',1))
print (str.split('w'))
</source>


 >>> print (str.split( ))[0]
 this
===string replace===

string = "geeks for geeks geeks geeks geeks" 
   
Prints the string by replacing geeks by Geeks  
 print(string.replace("geeks", "Geeks"))  
  
Prints the string by replacing only 3 occurrence of Geeks   
 print(string.replace("geeks", "GeeksforGeeks", 3))

==System-specific parameters and functions==
===Command line arguments - sys.argv===
required...
<br>import sys 
<br>usage....
<br>sys.argv[0] = name of script
<br>sys.argv[1] = first arg
<br>sys.argv[x] = xth arg, where x=some integer
<br>len(sys.argv) = number of args
<br> str(sys.argv) = argument list