DavidBuchanan314

#include <stdio.h>

#define SQ(x) (x)*(x)

#define M0(x,y) SQ(x)+SQ(y)<4?0:0xe0
#define M1(x,y,x0,y0) (SQ(x)+SQ(y)<4)?M0(SQ(x)-SQ(y)+(x0),2*(x)*(y)+(y0)):0xc0
#define M2(x,y,x0,y0) (SQ(x)+SQ(y)<4)?M1(SQ(x)-SQ(y)+(x0),2*(x)*(y)+(y0),x0,y0):0xa0
#define M3(x,y,x0,y0) (SQ(x)+SQ(y)<4)?M2(SQ(x)-SQ(y)+(x0),2*(x)*(y)+(y0),x0,y0):0x80
#define M4(x,y,x0,y0) (SQ(x)+SQ(y)<4)?M3(SQ(x)-SQ(y)+(x0),2*(x)*(y)+(y0),x0,y0):0x60
#define M5(x,y,x0,y0) (SQ(x)+SQ(y)<4)?M4(SQ(x)-SQ(y)+(x0),2*(x)*(y)+(y0),x0,y0):0x40

bearfrieze

Comprehensions in Python the Jedi way

by Bjørn Friese

Beautiful is better than ugly. Explicit is better than implicit.

-- The Zen of Python

I frequently deal with collections of things in the programs I write. Collections of droids, jedis, planets, lightsabers, starfighters, etc. When programming in Python, these collections of things are usually represented as lists, sets and dictionaries. Oftentimes, what I want to do with collections is to transform them in various ways. Comprehensions is a powerful syntax for doing just that. I use them extensively, and it's one of the things that keep me coming back to Python. Let me show you a few examples of the incredible usefulness of comprehensions.

vasanthk

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

1. Clarify and agree on the scope of the system

• User cases (description of sequences of events that, taken together, lead to a system doing something useful)
  • Who is going to use it?
  • How are they going to use it?

MichaelPote

#
# Himawari-8 Downloader
#
#
#
# This script will scrape the latest image from the Himawari-8 satellite, recombining the tiled image,
# converting it to a JPG which is saved in My Pictures\Himawari\ and then set as the desktop background.
#
# http://himawari8.nict.go.jp/himawari8-image.htm
#

bishboria

These links no longer work. Springer have pulled the free plug.

Graduate texts in mathematics

duplicates = multiple editions

A Classical Introduction to Modern Number Theory, Kenneth Ireland Michael Rosen

A Classical Introduction to Modern Number Theory, Kenneth Ireland Michael Rosen

paulirish

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.

Element APIs

Getting box metrics

• elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent

psi-4ward

CoreOS mdadm RAID1 for ROOT

• Setup SoftwareRAID for the CoreOS root partition without data-loss.
• Only for ext4!
• The Trick is to use the right volume label and fs-types :)
• We assume CoreOS is on /dev/sdaX and the second RAID Device is /dev/sdb
• Drawback: only / gets mirrored, Node goes down when sda fails

1. Boot into any recovery system like Grml
2. If not already done: install CoreOS

Jaza

*

aras-p

// Just before switching jobs:
// Add one of these.
// Preferably into the same commit where you do a large merge.
//
// This started as a tweet with a joke of "C++ pro-tip: #define private public",
// and then it quickly escalated into more and more evil suggestions.
// I've tried to capture interesting suggestions here.
//
// Contributors: @r2d2rigo, @joeldevahl, @msinilo, @_Humus_,
// @YuriyODonnell, @rygorous, @cmuratori, @mike_acton, @grumpygiant,

dypsilon

Backend Development

• node.js
  • Installation paths: use one of these techniques to install node and npm without having to sudo.
  • Node.js HOWTO: Install Node+NPM as user (not root) under Unix OSes
  • Felix's Node.js Guide
  • Creating a REST API using Node.js, Express, and MongoDB
  • Node Cellar Sample Application with Backbone.js, Twitter Bootstrap, Node.js, Express, and MongoDB
  • JavaScript Event Loop
• Node.js for PHP programmers