The document provides an overview of Python, highlighting its ease of learning, dynamic typing, fast development cycle, and high-level data structures. It includes examples of Python syntax, data types, and structures like lists, tuples, dictionaries, and classes, alongside references to related resources and libraries. Additionally, it discusses the Timemap and Memento concepts with links to source code and documentation.

1. Python
Scott G. Ainsworth
for ODU ACM
22 Sept 2011

2. What is Python?
 Easy to learn
 Simple syntax
 Dynamic typing
 High-level data structures  Free
 Linux/Unix, OS X, Windows
 MIT’s language of choice

3. Why Python?
 Fast development cycle
 Interactive & edit, debug/run
 vs. edit, compile, debug/run
 Extensive standard and add-on libraries
 (MIT’s language of choice)
 Python, Jython, & IronPython
 Google AppEngine

4. Basic Syntax
 Block structured
 But no braces
 Indent defines blocks
def fib(n):
a, b = 0, 1
while b < n:
print b,
a, b = b, a+b

5. Numbers & Strings
 Integers: -231 – 231-1  'value' == "value"
 5 + 23
 """multiple
 Long: unlimited lines"""
 1234567890123456789  u'unicode'
 Boolean:  'substring'[2:5] == 'bst'
 True or False
0 or 1
 Real and Complex:
 1.25 / 6.3
 Complex(1.1,2.2)

6. Sequence Types
 Lists
 primes = [ 2, 3, 5, 7, 11, 13, 17, 19, 23 ]
 primes.append(27)
 Primes[-2:] = [ 23, 27 ]
 Tuples
 primes = ( 2, 3, 5, 7, 11, 13, 17,19, 23 )
 primes.append(27) # fails, tuples are immutable
 primes[-2:] = ( 23, 27 )
 Strings are an immutable list of single characters

7. Dictionaries & Sets
 Dictionaries
 pdict = { "p1" : 2, "p2" : 3, "p3" : 5 }
 pdict["p4"] = 7
 pdict["p2"] == 3
 Sets
 primes = Set([ 2, 3, 5, 7, 11, 13, 17,19, 23 ])
 primes.append(27) # fails, set are unordered
 primes.add(27) # succeeds

8. Classes
Class complex:
"""implement complex numbers"""
def __init__(self, r, i):
self.__r = r
self.__i = i
def isreal(self):
return self.c == 0
def __add__(self, c):
return complex(self.r + c.r, self.i + c.i)

9. Memento & Timemap for
www.cs.odu.edu
http://api.wayback.archive.org/memento/timemap/link/http://www.cs.odu.edu
1. <http://www.cs.odu.edu>; rel="original",
2. <http://api.wayback.archive.org/list/timemap/link/http://www.cs.odu.edu>;
rel="timemap"; type="application/link-format”,
3. <http://api.wayback.archive.org/memento/19970102130137/http://cs.odu.edu/>;
rel="first memento"; datetime="Thu, 02 Jan 1997 13:01:37 GMT”,
4. <http://api.wayback.archive.org/memento/19970606105039/http://www.cs.odu.edu/
>; rel="memento"; datetime="Fri, 06 Jun 1997 10:50:39 GMT",
Output from timemap.py test
1. Original: http://www.cs.odu.edu
2. Time Map:
http://api.wayback.archive.org/list/timemap/link/http://www.cs.odu.edu
3. First Memento:
(datetime.datetime(1997, 1, 2, 13, 1, 37, tzinfo=tzutc()), 'http://api.wayback.archive.o
rg/memento/19970102130137/http://cs.odu.edu/')
4. 1997-06-06 10:50:39+00:00 =
http://api.wayback.archive.org/memento/19970606105039/http://www.cs.odu.edu/

10. timemap.py Output
Original: http://www.cs.odu.edu
Time Bundle: http://api.wayback.archive.org/list/timebundle/
http://www.cs.odu.edu
Time Gate: http://api.wayback.archive.org/list/timegate/
http://www.cs.odu.edu
Time Map: http://api.wayback.archive.org/list/timemap/link/
http://www.cs.odu.edu
First Memento: 1997-01-02 13:01:37+00:00
Last Memento: 2011-07-20 01:58:31+00:00
Mementos:
1997-06-06 10:50:39+00:00 = http://api.wayback.archive.org/memento/
19970606105039/http://www.cs.odu.edu/
1997-10-10 20:16:32+00:00 = http://api.wayback.archive.org/memento/
19971010201632/http://www.cs.odu.edu/

11. Code Walk Through
 class TimeMap: Memento timemap container class
 class TimeMapTokenizer: Helper class to tokenize a link-style
timemap
 __main__: Used for quick unit testing
Download the code:
http://www.cs.odu.edu/~sainswor/uploads/Downloads/timemap.py

12. Summary
 Easy to learn  Fast development cycle
 Dynamic typing  Extensive standard and
add-on libraries
 High-level data structures
 Widely-supported
 Free
 Linux/Unix, OS X, Windows

13. Questions?

14. Links
 Slides: http://www.cs.odu.edu/~sainswor/uploads/Downloads/ACM-Python.py
 Code: http://www.cs.odu.edu/~sainswor/uploads/Downloads/timemap.py
 Python: http://www.python.org
 Python Docs: http://docs.python.org
 Python Libraries: http://pypi.python.org