Demographic Data with Zero-Truncated Poisson

The zero-truncated Poisson distribution is useful to model certain demographic data, such as sizes of households and families ​1​. This post illustrates this on historical data from the United Kingdom and demonstrates how to assess the goodness-of-fit in Python. The zero-truncated Poisson distribution is defined as\begin{align}\mathbf{P}\{Y=x\} = \mathbf{P}\{ X = x | X > 0\}, …

Diagnosing regression with interactive QQ plots

QQ plots, despite their importance, are not well-supported in Python, as of the moment of writing this note. The package statsmodels offers plots of rather poor quality and non-interactive, and even Plotly doesn’t come with its own recipe. In this note, I am sharing how to build an interactive QQ plot and apply it to …

Compiling Torch Code – Example on Memory Reduction

Staring from the version 2.x PyTorch, a popular deep-learning framework, introduces a JIT compiler torch.compile. In this post, I am sharing a non-trivial example demonstrating how this tool can reduce memory footprint on GPU. The point of departure is a sub-routine which computes similarity, similar to covariance but not as friendly to compute. For two …

Lego Bricks in LaTeX

Who does not enjoy lego bricks, raise a hand! In this post, I am sharing an elegant and efficient way of plotting bricks under 3d view in TikZ. Briefly speaking, it utilizes canvas transforms to plot facets, and describes boundaries of studs in a simple way with cylindrical coordinates based on the azimuth angle (localizing …

Cylinders in LaTeX the Easy and Correct Way

Drawing cylinders in vector graphic is a common task. It is less trivial as it looks at first glance, due to the challenge of finding a proper projection. In this post, I share a simple and robust recipe using the tikz-3dplot package of LaTeX. As opposed to many examples shared online, this approach automatically identifies …

Automating Accessors and Mutators Tests

In object-oriented programming, there are plenty of accessors and mutators to test. This post demonstrates that this effort can be automated with reflection 🚀. The inspiration came from discussions I had with my students during our software-engineering class: how to increase code coverage without lots of manual effort? 🤔 Roughly speaking, the reflection mechanism allows …