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/*
The MIT License (MIT)

Copyright (c) 2014 Ismael Celis

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is

dhilip89

DHT Walkthrough Notes

I've put together these notes as I read about DHT's in depth and then learned how the libtorrent implementation based on the Kademlia paper actually works.

What problem does this solve?

400,000,000,000 (400 billion stars), that's a 4 followed by 11 zeros. The number of atoms in the universe is estimated to be around 10^82. A DHT with keys of 160 bits, can have 2^160 possible numbers, which is around 10^48

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/**
 * wraps a promise in a timeout, allowing the promise to reject if not resolve with a specific period of time
 * @param {integer} ms - milliseconds to wait before rejecting promise if not resolved
 * @param {Promise} promise to monitor
 * @Example
 *  promiseTimeout(1000, fetch('https://courseof.life/johndoherty.json'))
 *      .then(function(cvData){
 *          alert(cvData);
 *      })
 *      .catch(function(){

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// run with : 
// node --trace_deopt --allow-natives-syntax FILENAME

function adder(a, b) {
    return new Function('a', 'b', 'return b%2 ? a + b : b%3 ? a - b : b%5 ? b / a : a * b')(a, b);
}
function addereval(a, b) {
    return eval('b%2 ? a + b : b%3 ? a - b : b%5 ? b / a : a * b');
}

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// http://www.nullskull.com/a/768/7zip-lzma-inmemory-compression-with-c.aspx
// http://www.7-zip.org/sdk.html
namespace SevenZip.Compression.LZMA
{


    public static class SevenZipHelper
    {

dhilip89

d3.transform = function(string) {
  d3_transformG.setAttribute("transform", string);
  var m = d3_transformG.transform.baseVal.consolidate().matrix;
  if (m.a * m.d - m.b * m.c) return new d3_transform(m); // if invertible
};

// Compute x-scale and normalize the first row.
// Compute shear and make second row orthogonal to first.
// Compute y-scale and normalize the second row.
// Finally, compute the rotation.

dhilip89

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

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Device	OS	OS version	Browser	Browser version	WebGL	WebGL2
Apple iPad 5th	iOS	11.0.3	Mobile Safari	11.0	X
Apple iPad Air 2	iOS	8.4	Mobile Safari	8.0	X
Apple iPad Mini 3	iOS	8.1.2	Mobile Safari	8.0	X
Apple iPad Pro	iOS	11.2.1	Mobile Safari	11.0	X
Apple iPhone 5S	iOS	8.1.3	Mobile Safari	8.0	X
Apple iPhone 6 Plus	iOS	8.1	Mobile Safari	8.0	X
Apple iPhone 6	iOS	8.1.3	Mobile Safari	8.0	X
Apple iPhone 6S Plus	iOS	9.0.1	Mobile Safari	9.0	X

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function worker() {
  setInterval(function() {
    postMessage({foo: "bar"});
  }, 1000);
}

var code = worker.toString();
code = code.substring(code.indexOf("{")+1, code.lastIndexOf("}"));

var blob = new Blob([code], {type: "application/javascript"});

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/**
 * 1. Original JS Implementation by Jeff Greenberg 2/2001 - http://home.earthlink.net/~kendrasg/info/js_opt/
 * 2. (fast duff's device) from an anonymous donor to Jeff Greenberg's site
 * 3. (faster duff's defice) by Andrew King 8/2002 for WebSiteOptimization.com
 * 4. bug fix (for iterations<8) by Andrew B. King April 12, 2003
 */
function duffsDevice (iterations) {
  var testVal = 0,
      n = iterations % 8;