I was showing a friend my typed dataframe API. The whole pitch was: look, you derive a schema from your data, and then the compiler catches column name typos, type mismatches, all the stuff that would otherwise blow up at runtime. I had a nice demo ready using the Kaggle credit card fraud dataset (about 284,000 rows, 31 columns).

Every dataframe library ships with hundreds of operations. pandas alone has over 200 methods on a DataFrame. Is pivot different from melt? Is apply different from map? What about transform, agg, applymap, pipe? Some of these seem like the same operation wearing different hats. Others seem genuinely distinct. Without a framework for telling them apart, you end up memorizing APIs instead of understanding structure.

A lot of tabular modeling gets easier the moment you stumble onto the right derived quantity. Not something mysterious or “deep.” It’s usually something you can name: a ratio that turns two raw columns into a rate; a difference that becomes a margin; a simple count that captures what a bunch of messy fields were hinting at.

I couldn’t find any instructions online so I thought I’d post them here for anyone who goes through a similar struggle.

Introduction

This post kicks off the second part of a hands-on series about program synthesis. We’ll apply the previously explored technique (an enumerative bottom-up search) to a slightly more realistic problem: automatically generating features for the Iris dataset.

There’s been a lot of work in the Haskell ecosystem that has made it easier to write interactive Kaggle-like scripts. I’d like to showcase the synergy between 3 such tools: dataframe (my own creation), hasktorch, and IHaskell.

Introduction

This post kicks off a hands-on series about program synthesis—the art of teaching machines how to generate code. We’ll build a tiny, FlashFill-style synthesiser that learns to turn strings like “Joshua Nkomo” into “J. Nkomo” from input/output pairs. We’ll see how to define a tiny string-manipulation language, write an interpreter, and search the space of programs to find one that solves our toy problem.

My fondness for alternative Haskells

I’ve been working on a dataframe implementation in Haskell for about a year now. While my focus has been on ergonomics the question of performance has inevitably come up. I haven’t made significant performance investments but I thought it might be worth snapshotting the performance to establish a baseline.