Christian Rotzoll rtzll

2019 update: this essay has been updated on my personal site, together with a followup on how to get started

2020 update: I'm now writing a book with updated versions of all these essays and 35 other chapters!!!!

1. Learn in public

If there's a golden rule, it's this one, so I put it first. All the other rules are more or less elaborations of this rule #1.

You already know that you will never be done learning. But most people "learn in private", and lurk. They consume content without creating any themselves. Again, that's fine, but we're here to talk about being in the top quintile. What you do here is to have a habit of creating learning exhaust. Write blogs and tutorials and cheatsheets. Speak at meetups and conferences. Ask and answer things on Stackoverflow or Reddit. (Avoid the walled gardens like Slack and Discourse, they're not public). Make Youtube videos

High-Performance Matrix Multiplication

This is a short post that explains how to write a high-performance matrix multiplication program on modern processors. In this tutorial I will use a single core of the Skylake-client CPU with AVX2, but the principles in this post also apply to other processors with different instruction sets (such as AVX512).

Intro

Matrix multiplication is a mathematical operation that defines the product of

How Clojure's documentation can leapfrog other languages

Summary

I made a documentation generator that cashes in on Clojure's dynamism. See the play-cljs docs (a ClojureScript game library) for an example of its output.

The Problem

Like many of you, I've often wondered what my final regret will be on my deathbed. My best guess came to me in a dream recently. I was walking across the charred earth of an apocalyptic future world, maneuvering around the remains of the less fortunate. I was startled to find a young girl, barely holding onto her life. She murmured something to me. I asked her to repeat it, and she said more loudly: "I...wish your Clojure projects didn't have such crappy documentation."

	import openai
	import streamlit as st
	from streamlit_chat import message
	from dotenv import load_dotenv
	import os
	from langchain.embeddings.openai import OpenAIEmbeddings
	from langchain.vectorstores import Chroma
	import openai
	from langchain.document_loaders import UnstructuredMarkdownLoader
	from langchain.chains.question_answering import load_qa_chain

	import openai
	import streamlit as st
	from streamlit_chat import message
	from dotenv import load_dotenv
	import os
	from langchain.embeddings.openai import OpenAIEmbeddings
	from langchain.vectorstores import Chroma
	import openai
	from langchain.document_loaders import UnstructuredMarkdownLoader
	from langchain.chains.question_answering import load_qa_chain

	import * as d3 from "d3";
	import {
	eachMonthOfInterval,
	endOfMonth,
	format,
	isSameMonth,
	parseISO,
	startOfMonth,
	} from "date-fns";
	import useMeasure from "react-use-measure";

	import { isTest } from "@/lib/constants";
	import { Dialog } from "@headlessui/react";
	import { motion } from "framer-motion";

	const TRANSITIONS = {
	DURATION: !isTest ? 0.5 : 0,
	EASE: [0.32, 0.72, 0, 1],
	};

	function Modal({ onClose = () => {}, initialFocusRef, children }) {

	function findBreakoutElem(rootElem = document.body) {
	function checkElemWidth(elem) {
	if (elem.clientWidth > window.outerWidth) {
	console.log("The following element has a larger width than the window's outer width");
	console.log(elem);
	console.log('<-------------------------------------------------------------------->');
	} else if (elem.scrollWidth > window.outerWidth) {
	console.log("The following element has a larger width than the window's scroll width");
	console.log(elem);
	console.log('<-------------------------------------------------------------------->');

	#!/bin/bash

	while :; do

	verf=$(cat /dev/urandom \| tr -dc '0-9' \| fold -w 8 \| head -n 1)
	pin=$(cat /dev/urandom \| tr -dc '0-9' \| fold -w 5 \| head -n 1)

	ip=$(printf "%d.%d.%d.%d\n" "$((RANDOM % 256))" "$((RANDOM % 256))" "$((RANDOM % 256))" "$((RANDOM % 256))")

	const MY_DOMAIN = "agodrich.com"
	const START_PAGE = "https://www.notion.so/gatsby-starter-notion-2c5e3d685aa341088d4cd8daca52fcc2"
	const DISQUS_SHORTNAME = "agodrich"

	addEventListener('fetch', event => {
	event.respondWith(fetchAndApply(event.request))
	})

	const corsHeaders = {
	"Access-Control-Allow-Origin": "*",