R has a reputation as a statistics tool — the thing you reach for when you need a regression or a publication-quality plot. That framing undersells it. The part of R that earns its place in a practical engineering workflow is its I/O story: the breadth of data sources it can connect to, and the consistency of the analysis layer once data arrives in a data frame regardless of where it came from.
Read more →Colour blindness affects roughly 8% of men and 0.5% of women with Northern European ancestry. For a data visualisation that uses colour as the primary encoding — a choropleth, a multi-series line chart, a heatmap — that’s a meaningful share of the audience for whom the visual may be conveying the wrong information, or none at all.
The right time to test this is during design, not after a complaint. ImageMagick’s -color-matrix flag lets you simulate the major forms of colour vision deficiency directly on any image — screenshots, design exports, chart renders — from the command line. This makes it scriptable, batchable, and easy to drop into a CI pipeline alongside screenshot tests.
SVG paths are written as a single d attribute — a mini-language of commands and coordinates that describes shapes. Each command is a letter; uppercase means absolute coordinates, lowercase means relative to the current position. This is a reference for all path commands with examples, followed by a worked pie chart that puts the arc command through its paces.
The full MDN reference lives at developer.mozilla.org/en-US/docs/Web/SVG/Tutorial/Paths.
M x y
Lifts the pen and moves to (x, y) without drawing. Every path starts with an M. On its own it’s invisible — it’s a positioning command.