Modeling the Covid-19 Outbreak with J (2020)

- J is a niche, array-oriented programming language (descended from APL) known for its extreme concision and mathematical notation. It is rarely used in mainstream data science but has a devoted following. - This post appeared in March 2020, at the very start of the global pandemic, when simple epidemiological models (like the SIR model shown) were being widely discussed by the public for the first time. - The SIR model divides a population into Susceptible, Infected, and Recovered compartments; it is the classic starting point for epidemic modeling. - The article is interesting as a historical artifact: it demonstrates how even an obscure language like J could be used to simulate the pandemic in real time, and it reflects the early-pandemic moment when many technically-minded people were trying to understand exponential growth and "flattening the curve."