Code
Here is a list of some of my python coding projects.
 Fitting an ellipse.
Suppose a rockets moves around the earth in a perfectly circular orbit.
Suddenly the captain decides to hit the break for an infinitely short amount of time.
The orbit should then become an ellipse.
I once analyzed this behavior with the
scipy
s numerical differential equation solver. The result was a set of points that, once plotted, appeared to by elliptical. To check whether this was indeed true, I developed this code.
Probability theory related

Weighted random shuffling This code helps to sample from a list of items, but such that the selection of items is not uniformly distributed, which you would get with
random.sample
, but in proportion to a given set of weigths $w$. 
Markov chains Generating Markov chains, and computing the stationary distribution, can be a bit painfull. With this code it is hopefully a bit simpler.
Miscellaneous
 Memoization Examples Memoization is extremely useful when some computations involve recursions, such as in dynamic programming problems with finite horizon. Here I show two simple examples how to apply this programming concept in python.