Computational Modeling
Fall 2005

For today, you should have:

1) created an account on the wiki (http://wb/cm/cm-wiki.cgi/)

2) signed up for the class mailing list 
   (http://lists.olin.edu/mailman/listinfo/CompMod)

3) read a chunk of your book

4) done HomeworkOne


Today's outline:

1) present reviews from last time

2) identify recurring examples and concepts, and think about
   creating pages for some of them.  When we have roughly one
   page per person, each of you will be in charge of maintaining
   an example/concept page.

3) trade books

4) learn a little Python


For next time you should:

1) do HomeworkTwo

2) get a Python book


Python crash course
-------------------

Goal: introduction for people who don't know Python, review
      for those who do.

      More Pythonic than Software Design.


Python for Java programmers:

1) Python is dynamically-typed, so no need to declare variables

   x = 5
   x = 'allen'
   x = Histogram()


2) Python uses indentation to indicate nesting, no squiggly-braces
   and no semi-colons.

   The first line of a compound statement is a header that ends
   with a colon:

   if x<0 or x>100:
       print 'Pirate falls!'

   def square(x):
       return x**2

   
3) lists and dictionaries are built-in types with special syntax

   t = [1, 2, 3]
   print t[1]

   d = {}
   d['allen'] = 17


4) Python's OO features are very similar to Java's

   class Histogram(dict):
       def __init__(self, t):
           for x in t:
               self.count(x)

       def count(self, x):
           try:
               self[x] += 1
           except KeyError:
               self[x] = 1

   __init__ is a special name for the constructor, so when
   you invoke Histogram(), Python creates a new object and
   invokes __init__ on it

   exception handling!


5) Lots of online documentation at python.org