Programming on mellowd.co.uk

Visualising Big O notation

Mon, 05 Oct 2015 17:38:39 +0000

I’m currently learning as much computer science as I can on the side. I’ve come across Big O notation a few times already, and while I understand it, I’m much more of a visual guy.

It’s rather easy to use Python and matplotlib to graph out how a function’s execution time grows as the size of the input grows. The important things to note is not total execution time, but rather how the runtime of that function grows in relation to the input size. This can be plotted onto a graph which should give us a nice representation of Big O notations.

Linked lists

Thu, 14 May 2015 17:28:16 +0000

Python has a rather handy list method. It allows you to add and remove items at will. How it actually does this is rather elaborate and you can read all about it over here.

C doesn’t give you the same flexibility. When you create an array, it is of X size. That size cannot change as there is no guarantee that memory on either side of the existing array space is even free for you. For this reason there is a handy data structure called the linked list.

Structs in C

Tue, 05 May 2015 20:53:04 +0000

Back in March 2014 I wrote an app in Python that would log in and check various OSPF properties.

When putting the data into a structure, I was limited both by knowledge and Python at the time. I ended up using a dictionary which worked rather well, but I was never 100% happy with it.

Recently I’ve stumbled across structs in C, in which I can make pretty much any data structure I would like.

Basic OOP Python

Tue, 28 Oct 2014 13:43:30 +0000

I’ve just started with object oriented programming in Python so I thought I’d cover some of the basics here. Please don’t assume this is a thorough tutorial on OOP!

The beauty of OOP is that it allows me to create a template with which I can create objects. The building blocks of the object sit in the class, while the object itself is created from that blueprint with various properties. I can then make as many of these objects as I desire from that single class. I can see this being very beneficial for certain types of programming (games especially)