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@jcchurch
jcchurch / diskstra.m
Created April 20, 2011 03:22
Dijkstra's Algorithm in Matlab
function D = dijkstra(G, pairs)
% This function takes an adjacency matrix called G
% and a p-by-2 matrix called pairs.
% The pairs matrix will contain pairs of indices.
% This function will determine the shortest distance from
% the first index in the pair to the second index for
% every pair in matrix pairs.
%
% The function will only return a p-by-1 matrix of shortest
% distances. I could use it to also return the shortest path,
@gavinandresen
gavinandresen / sendalert.cpp
Created December 15, 2011 16:30
Bitcoin CAlert code (without private key, of course)
#include "headers.h"
#include "net.h"
static const int64 DAYS = 24 * 60 * 60;
void ThreadSendAlert();
class CSendAlert
{
public:
@hellerbarde
hellerbarde / latency.markdown
Created May 31, 2012 13:16 — forked from jboner/latency.txt
Latency numbers every programmer should know

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

@chad3814
chad3814 / gist:2924672
Last active January 16, 2024 20:27
deleting array items in javascript with forEach() and splice()
// This is from my comment here: http://wolfram.kriesing.de/blog/index.php/2008/javascript-remove-element-from-array/comment-page-2#comment-466561
/*
* How to delete items from an Array in JavaScript, an exhaustive guide
*/
// DON'T use the delete operator, it leaves a hole in the array:
var arr = [4, 5, 6];
delete arr[1]; // arr now: [4, undefined, 6]
@AliMD
AliMD / gist:3344523
Created August 13, 2012 22:28
All github Emoji (Smiles)

All github Emoji (Smiles)

ali.md/emoji

:bowtie: | 😄 | 😆 | 😊 | 😃 | ☺️ | 😏 | 😍 | 😘 | :kissing_face: | 😳 | 😌 | 😆 | 😁 | 😉 | :wink2: | 👅 | 😒 | 😅 | 😓

😩 | 😔 | 😞 | 😖 | 😨 | 😰 | 😣 | 😢 | 😭 | 😂 | 😲 | 😱 | :neckbeard: | 😫 | 😠 | 😡 | 😤 | 😪 | 😋 | 😷

😎 | 😵 | 👿 | 😈 | 😐 | 😶 | 😇 | 👽 | 💛 | 💙 | 💜 | ❤️ | 💚 | 💔 | 💓 | 💗 | 💕 | 💞 | 💘 | ✨

@typeofgraphic
typeofgraphic / mapD3JsonGeocode.html
Created January 4, 2013 23:47
Adaptation of Google Maps + D3.js Data file looks like this: [ {"country": "eth", "city": "adis abeba", "time": "2012-12-04T04:00:00", "count": 5}, {"country": "deu", "city": "munich", "time": "2012-12-04T19:00:00", "count":21}, {"country": "chn", "city": "wuhan", "time": "2012-12-04T18:00:00", "count": 1}, {"country": "usa", "city": "winthrop",…
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no"/>
<script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=true"></script>
<script type="text/javascript" src="http://mbostock.github.com/d3/d3.js?1.29.1"></script>
<style type="text/css">
html, body, #map {
width: 100%;
@kyledrake
kyledrake / bitcoind.js
Last active December 20, 2015 16:38
Probably the smallest feature-complete bitcoind RPC interface in existence.
var request = require('request');
function Bitcoind(url) {
this.url = url;
};
Bitcoind.prototype.rpc = function(method, params, callback) {
this.request({jsonrpc: '2.0', method: method, params: params}, callback);
};
@scaryguy
scaryguy / change_primary_key.md
Last active July 15, 2024 16:57
How to change PRIMARY KEY of an existing PostgreSQL table? 
-- Firstly, remove PRIMARY KEY attribute of former PRIMARY KEY
ALTER TABLE <table_name> DROP CONSTRAINT <table_name>_pkey;
-- Then change column name of  your PRIMARY KEY and PRIMARY KEY candidates properly.
ALTER TABLE <table_name> RENAME COLUMN <primary_key_candidate> TO id;
@magicznyleszek
magicznyleszek / jekyll-and-liquid.md
Last active January 12, 2024 03:46
Jekyll & Liquid Cheatsheet

Jekyll & Liquid Cheatsheet

A list of the most common functionalities in Jekyll (Liquid). You can use Jekyll with GitHub Pages, just make sure you are using the proper version.

Running

Running a local server for testing purposes:

@Jonty
Jonty / uk_parl_wikipedia.md
Last active December 13, 2023 19:59
Every IP address in the UK Parliament netblock that has edited Wikipedia