Week 7: Recursion

    If you're confused as to why I included the picture above (and what it has to do with recursion - the mandatory topic this week), look at the picture on the cereal box. Then look at the picture on the cereal box on the picture of the cereal box. Then look at the picture of the cereal box on the picture of the cereal box on the the picture of the cereal box... You probably get the idea now.

    Recursion can definitely be a little overwhelming to think about at first. For me, the greatest mental barrier I had to overcome was figuring out how a function can be defined when what it does depends on what it does... when what it does hasn't been defined yet. Regardless of how involved this sounds, I found that once I went through a couple clear examples of recursive functions, there was really nothing so daunting about the concept at all.

   And  in some cases, a recursive function can truly be the simplest, most elegant, and most efficient way to tackle a problem. Take this example we did in class, that returns the nested depth of a list:

def nested_depth(L):
    """
    Return nested depth of list L.

    Nested depth is:
    0                                   --- if L is a non-list
    1 + maximum nested of elements of L --- if L is a list

    >>> nested_depth(3)
    0
    >>> nested_depth([1, 2, 3])
    1
    >>> nested_depth([1, [2, 3], 4])
    2
    """
    return (1 + 

            # maximum nested depths of elements of L, concatenated with 0
            # to deal with possibility that L is empty
            max([nested_depth(x) for x in L] + [0])

            # 0 if L is a non-list
            if isinstance(L, list) else 0)

Any iterative function that returns the same result would certainly be much longer and more complex, not to mention trickier to build and understand.

    Recursion is fun. Yay.

Week 6

    This week, assignment 1 was due. Luckily, I ended up finishing the project a few days prior to the due date, so I had a good amount of time to go over my code and make sure everything was clear and efficient. I also made an attempt at the bonus problem. My function passed the test case in the doc-string, so hopefully I'll get the extra credit!
    In class, we focused mainly on leaves and trees. I was a little confused at first, because I didn't really understand what the point of it was. It took me some time to really realize that  a tree is just an abstract data type like any other, with its own characteristics and features. I feel good about class this week; I feel like I have a good grasp on the material. Now time to study for the midterm!

Week 5

This week, we spent some time in class discussing Assignment II, "Towers of Anne Hoy". I decided to work on this project alone, so the extra help was certainly welcome. So far, I'm about half-way through. I'm having fun with it. I'm finding that my progress isn't really continuous, but sort of jolting, stop-start. I'm stuck; I figure it out; I work a little; then I'm stuck again. With this sort of assignment that requires so much intensive and constant problem solving, I think it really takes time to deeply understand what has to be done and how to approach it. I also found that it was really worth the effort to read through the starter code and make sure to fully understand it before going on and doing any actual coding. So hopefully the rest will go smoothly enough, and it won't be too much of a rush to meet the deadline.