In which python is great

Apr 22, 2012 - 02 p.m.

To me, python's greatest strength is that the syntax is almost identical to the form that programs take when they appear in your mind. This makes the time from the initial thought to final code shorter, and makes it easy for others reading your code to understand your thinking. This makes it ideal for interview problems, but mostly just makes it a joy to work with.

To profile some code that I had written, I was calculating the average of many page loads. My inital approach was to write down the numbers and then plug them into a calculator. Simple enough, but like most pure programming problems, very boring for numbers greater than three or four. Sounds like a good time for some python.

To start, I formatted my numbers as simply as possible. The file looked like this:

Baseline
Wall 130 45 300 312 60 77
CPU 100 50 330 300 60 78
Mem 2000 2121 400 3100 1945 1224

I wanted it to print out the name of the run (Baseline in this case), and then print an average of each measurement. The code I wrote was this:

f = open('runs', 'r')

for line in f:
    parts = line.split(' ')
    sum = 0
    count = 0
    for part in parts:
        try:
            n = int(part)
            sum += n
            count += 1
        except ValueError:
            print part

    try:
        print sum / count
    except ZeroDivisionError:
        pass

Short, and gets the job done. The best part is that it only took about five minutes from inception to working code. I needed to run it twice to get the names of the exceptions correct, but beyond that, it took me almost no time compared to the amount of time it saved, and that's a beautiful thing.

Could I have done it with awk? or excel? Certainly. However, one requires opening up excel (if you even have it. Also, yuck), and the other would require a bit of reading to figure out. Neither is really ideal. Although the awk one might be sort of fun. Perhaps we'll see about that in a future post.