Visualization toolmaker. Founder @observablehq. Creator @d3. Former @nytgraphics. Pronounced BOSS-tock.
testInstructions = parseProgram(test)
function parseProgram(input) {
return input.trim().split("\n").map(parseInstruction);
}
function parseInstruction(input) {
const [command, value] = input.split(/\s+/);
return {command, value: value ? +value : undefined};
}
testStates = [...executeInstructions(testInstructions)]
function* executeInstructions(instructions) {
let X = 1;
let cycle = 0;
for (const {command, value} of instructions) {
let delay;
function currentState(phase) {
return {cycle, phase, X, command, value, delay};
}
switch (command) {
case "noop": delay = 1; break;
case "addx": delay = 2; break;
default: throw new Error(`unknown command: ${command}`);
}
++cycle;
yield currentState("start");
while (--delay) {
yield currentState("end");
++cycle;
yield currentState("start");
}
switch (command) {
case "noop": break;
case "addx": X += value; break;
default: throw new Error(`unknown command: ${command}`);
}
yield currentState("end");
}
}
largeTestInstructions = parseProgram(largeTest)
largeTestEvaluation = [...executeInstructions(largeTestInstructions)]
sumSignalStrength(largeTestEvaluation)
function sumSignalStrength(states, cycles = [20, 60, 100, 140, 180, 220]) {
let sum = 0;
cycles = new Set(cycles);
for (const {cycle, phase, X} of states) {
if (phase === "start" && cycles.has(cycle)) {
sum += X * cycle;
}
}
return sum;
}
instructions = parseProgram(input)
states = [...executeInstructions(instructions)]
sumSignalStrength(states)
largeTestInstructions
renderCrt(largeTestInstructions)
function* renderCrt(instructions) {
let crt = "";
let i = 0;
yield crt;
for (const {cycle, phase, X} of executeInstructions(instructions)) {
if (phase === "start") {
if (i === 0) crt += "\n";
crt += Math.abs(X - i) < 2 ? "#" : ".";
yield crt;
i = (i + 1) % 40;
}
}
}
renderCrt(instructions)
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
