Object-Oriented Design Frequently Asked Questions

Python

Where do I find answers to questions about Python ?

Tutorials, references, and links kan be found at http://www.python.org.

How does one check whether an object `c` is of "type" `C` ?

For builtin types, one can use the operator type(). For example:

     >>> type(2)
     <type 'int'>

If we declare a class C and create an instance c as shown below, type() will give rather general information:

    >>> class C:
        pass
    >>> c=C()
    >>> type(C)
    <type 'classobj'>
    >>> type(c)
    <type 'instance'>

If we want to check whether c is an instance of class C, we can use the test
```
    >>> isinstance(c, C)
    True
    
```
This will evaluate to True if c is an instance of class C or any of C's sub-classes.
In recent versions of Python, it is possible to test for basic types with isinstance as in isinstance(1,int), isinstance(1.2,float) and isinstance([1,2],list).

How do I generate nice HTML from Python source code ?

Colorized pretty-printing for file code.py can be done with
```
enscript -Whtml -Epython --color code.py -o code.html
```
An API document for file code.py can be generated with
```
pydoc -w code
```

Assignments

What are the algorithms needed to `evaluate()` a spreadsheet ?

The topological sort and strong component algorithms are given here in pseudo-code. More details (on for example algorithm complexity) are found in the literature.

MUST we work in teams of 2 ?

You must work in a team of exactly two people. Previous experience has shown that after the initial transient chaos of finding a partner, this works really well. Try to find a team partner after class. Remember that "pair programming" requires you to actually work together (same place, same time). You may form different teams for different assignments.