Python Tutorial

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I've been learning Python and here is what I have learned so far:

1. Python is a scripted language

2. In Python, indentation matters because it's how logic blocks are grouped together

3. Python is not strongly typed like C++, C#, and Java

4. Python has the following data types - dynamic

a. Lists - dynamic array can be appended, sorted, and all kinds of goodies; defined by []

b. Tuples - array that can't be changed

c. Dictionaries - ie {'key': 'value', 'a' : 'b'}, d['k'] = 'v‘

d. integer

e. float

f. string

g. Special statements

i pass,del, raise, assert, exec
ii global
iii break
iv continue
v try

5. For loops

for item in sequence:

Statements

else:

statements

– Example:

for item in (1,3,5,7,9,15,2003):

print item

for item in xrange (1, 50):

sum += item

6. While loops
While ... [else]

while a == b:

work ()

else:

finalize ()

7. If statements
If ... [elif ... else]

if a == c:

print “a equals c”

else:

print “a and c are different”

8. Functions and Procedures
def name(arg1, arg2, ...):
"""documentation""" # optional doc string
statements

return # from procedure
return expression # from function

9. Exception
def foo(x):
return 1/x

def bar(x):
try:
print foo(x)
except ZeroDivisionError, message:
print "Can’t divide by zero:", message

bar(0)

10 File Input/output

f = open(filename[, mode[, buffersize])
mode can be "r", "w", "a" (like C stdio); default "r"
append "b" for text translation mode
append "+" for read/write open
buffersize: 0=unbuffered; 1=line-buffered; buffered

methods:
read([nbytes]), readline(), readlines()
write(string), writelines(list)
seek(pos[, how]), tell()
flush(), close()
fileno()

Some links to examples in Python
Simple Sample Python Code
Python Recipes