An ag(e)ing hacker - posts tagged as "tutorial"

Languages and complexity, Part I: why I love Anki — 2024-01-02 19:47 Updated: 2024-01-28 10:13

Lately I have not been as active in GNU (https://www.gnu.org) as I would have liked—which I plan to change. Apart from work I was busy with happy family life next to E.; and, I guess, with contemplating the dismal state of the West as it descends further and further into tyranny amid the general indifference. Maybe in part seeking solace from the news I focused with renewed intensity on my hobby, studying the Russian language for no reason much more practical than my love for Nineteenth-Century novels. I have heard more than one Russian teacher vocally disapproving of literature as [...] Read more

A practical GNU epsilon tutorial — 2013-08-23 12:54 Updated: 2023-09-29 17:57

A practical GNU epsilon tutorial Audience Lexical conventions Rationale and introduction My PhD thesis Implementation, and the relation beteen epsilon0 and epsilon1 The bootstrap problem Setup Writing more comfortably, from ‘guile+whatever’ and Emacs Basics of epsilon1 The stuff values are made of: fixnums, pointers, buffers Error situations in epsilon1 Slightly higher-level data structures: vectors, strings, boxes, tuples, records Equality and boxedness tags Lists, and simple programming examples Digression: a look at epsilon0 Practical programming in epsilon1 Sums A programming example: structural equality with boxedness tags A look at reflective data structures ‘e1:define’ is just a macro! S-expressions What’s the point [...] Read more

Happy pi approximation day 2013 — 2013-07-21 12:34 Updated: 2014-07-21 21:14

The fraction 22/7 has been known since antiquity as a simple rational approximation of pi. The fraction decimal expansion is 3.(142857); since pi is about 3.141592653589793, the approximation has three correct digits. Of course nowadays we can compute much better approximations with computers, and billions of digits are known: <http://en.wikipedia.org/wiki/Approximationsofπ> is a nice review also explaining some efficient computation methods. For example if you want to obtain a lot of pi digits in a short time you may like the series by Ramanujan, yielding very good approximations even with a small number of terms; but that’s not the point now. [...] Read more