Tying Up Loose Ends

1
Tying Up Loose Ends
2
Topics

• Interpreter working directory (files)
• Complex Data structures
• Specialized Data structures

3
Working Directory

• Sometimes we dont want to write in a complete
  path for our files
• So what does this do?
• fopen("test.txt)
• How can we get it to do what we want?

4
Current Working Directory

• File names without paths default to the current
  working directory that the python interpreter was
  started in
• So the trick is to start the interpreter in the
  directory that we want to be current.

5
CWD Advantages

• CWD is already in sys.path
• You can import modules easily
• Files dont require the full path

6
Complex Data Structures

• 2D lists
• 3D lists
• Sparse structures with maps

7
2D Lists

• Why?
• Game boards
• Lookup tables
• How
• X 0 for i in xrange(10) for j in
  xrange(10)
• Are there any other ways?

8
Using 2D lists

• X34 1
• How about pretty printing it?
• for i in X
• for x in i
• print x,
• print

9
3D Lists

• These are like 2D only one more dimension
• We may use these for 3D board games, but they are
  less common than 2D structures
• How do we make them?
• ?
• How do we use them?
• ?

10
Cheating with Maps

• We can use tuples and maps to cheat
• Creating
• X
• Reading
• X.setdefault((3,4),0)
• Writing
• X(3,4) 3

11
Challenge

• Build a 2D Tic Tac Toe game
• Build a 3D Tic Tac Toe game