TDD katas for Data Scientists
Whenever I talk about TDD to data science and data engineering folks, they say that either TDD is not working for algorithmic work, or “I’ve tried FizzBuzz and it is not fun [^1]”. I can understand. Most katas in places like kata-log are more oriented towards more traditional software developers.
So, I’ve decided to come up with some katas that might be more interesting for DS folks. Here they are.
ModPlus
ModPlus is a simple hashing algorithm. It takes in a positive integer X and returns a combinatorial sum of a binary representation of X after it is split into chunks of given length.
For example, modplus(12, chunk_length=3) should return 6.
Variation: ModPlusDot. Instead of combinatorial sum, use a combination of binary AND and OR when combining chunks.
Simple enough for an algorithmic problem. Skills to practice: splitting the problems into smaller problems, naming things, simplify by extraction, refactoring while in green, make it work first.
Practical application: Luhn algorithm.
2D vector
Imagine you are working for Khan Academy (KA). KA wants to modernize their basic math classes, especially the display. Implement a cartesian 2D Vector class, that supports scalar multiplication, addition with another Vector, norm (magnitude) and dot product between 2 vectors(see vector).
This is more of a design kata, but still requires to implement a couple of formulas.