Lessons: at the prompt
Ten short lessons on using Leonardo as a calculator you talk to — no Scala, no build, no installation. Everything here runs in the browser REPL: open it in another tab and type along.
Start with R1 — Five minutes, or pick a lesson below.
If you would rather call Leonardo from your own Scala code, the other branch is Lessons: in your program.
The lessons
| R1 | Five minutes | What it is for, before any vocabulary |
| R2 | Expressions and free variables | Why an unknown name is an answer, and two notation traps |
| R3 | Naming things | := versus =, definitions that track their dependencies |
| R4 | Calculus | derive, integral, limit, taylor — and what a refusal looks like |
| R5 | Equations | solve, inequalities, systems — and the answer it stores for you |
| R6 | Matrices | Literals, det/inv, decompositions, stacked display |
| R7 | Drawing and sampling | plot in the browser, samples everywhere, and dropped points |
| R8 | Exact arithmetic | Fractions instead of decimals; the two precisions |
| R9 | Your session | Saving, loading, sharing, and the settings worth knowing |
| R10 | The terminal REPL | The same language offline, and the three differences |
What this branch assumes
Ordinary mathematics — that you know what a derivative is. It does not assume you have used a computer algebra system before, and it teaches the command language, not the library.
Each lesson ends with an exercise, and every transcript on these pages is executed when the site is built, so what you read is what the library actually answers.
A note on the two REPLs
They are the same program. Session — the whole command language — is shared, so a command that works in the browser works in the terminal, with two exceptions called out where they arise: the terminal cannot draw, and the browser has no file system. R10 covers the differences.