---
title: 'Math and list recipes'
part: 'Part IX — Standard Library and Reusable Design'
partNumber: 9
order: 2
subtitle: 'std.mathx and std.listx: easing, probability, sorting, grouping, and sequence tools'
---

_Content coming soon._ The emphasis is on recurring generative recipes: easing a parameter,
interpolating headings across the wrap point, weighted choice without hidden randomness, and
turning lists into ordered, paired, chunked, or grouped design data.

<Run>{`import std.mathx.easeinout as ease
import std.mathx.lerpheading as turnbetween

repeat 24 [
let t = (repcount - 1) / 23
seth turnbetween(330, 30, t)
fd lerp(2, 10, ease(t))
]`}</Run>

<Checkpoint chapterId="ch-55">Chapter content coming soon.</Checkpoint>