jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

mucar

var colorArray = ['#FF6633', '#FFB399', '#FF33FF', '#FFFF99', '#00B3E6', 
		  '#E6B333', '#3366E6', '#999966', '#99FF99', '#B34D4D',
		  '#80B300', '#809900', '#E6B3B3', '#6680B3', '#66991A', 
		  '#FF99E6', '#CCFF1A', '#FF1A66', '#E6331A', '#33FFCC',
		  '#66994D', '#B366CC', '#4D8000', '#B33300', '#CC80CC', 
		  '#66664D', '#991AFF', '#E666FF', '#4DB3FF', '#1AB399',
		  '#E666B3', '#33991A', '#CC9999', '#B3B31A', '#00E680', 
		  '#4D8066', '#809980', '#E6FF80', '#1AFF33', '#999933',
		  '#FF3380', '#CCCC00', '#66E64D', '#4D80CC', '#9900B3', 
		  '#E64D66', '#4DB380', '#FF4D4D', '#99E6E6', '#6666FF'];

sam

package util

object Slug {
  def apply(input:String) = slugify(input)

  def slugify(input: String): String = {
    import java.text.Normalizer
    Normalizer.normalize(input, Normalizer.Form.NFD)
      .replaceAll("[^\\w\\s-]", "") // Remove all non-word, non-space or non-dash characters
      .replace('-', ' ')            // Replace dashes with spaces

atenni

Problem: When linking to the raw version of a gist, the link changes with each revision.

Solution:

To return the first file from a gist: https://gist.github.com/[gist_user]/[gist_id]/raw/

• Example: https://gist.github.com/atenni/5604522/raw/
• Works even when you change the filename.

To get a file from multi–file gist: https://gist.github.com/[gist_user]/[gist_id]/raw/[file_name]

shawndumas

[mergetool]
    prompt = false
    keepBackup = false
    keepTemporaries = false

[merge]
    tool = winmerge

[mergetool "winmerge"]
    name = WinMerge

liabru

var testObject = {
    pi: Math.PI,
    e: Math.E,
    one: 1,
    x: 1.5,
    str: "1.2345"
};
 
var places = 2,
    json = JSON.stringify(testObject, function(key, value) {

owainlewis

*.class
*.log

# sbt specific
.cache/
.history/
.lib/
dist/*
target/
lib_managed/

leommoore

File Magic Numbers

Magic numbers are the first bits of a file which uniquely identify the type of file. This makes programming easier because complicated file structures need not be searched in order to identify the file type.

For example, a jpeg file starts with ffd8 ffe0 0010 4a46 4946 0001 0101 0047 ......JFIF.....G ffd8 shows that it's a JPEG file, and ffe0 identify a JFIF type structure. There is an ascii encoding of "JFIF" which comes after a length code, but that is not necessary in order to identify the file. The first 4 bytes do that uniquely.

This gives an ongoing list of file-type magic numbers.

Image Files

protrolium

ffmpeg

Converting Audio into Different Formats / Sample Rates

Minimal example: transcode from MP3 to WMA:
ffmpeg -i input.mp3 output.wma

You can get the list of supported formats with:
ffmpeg -formats

You can get the list of installed codecs with:

joshuashaffer

#!/usr/bin/env python
#
# Tests distance between point and triangle in 3D. Aligns and uses 2D technique.
#
# Was originally some code on mathworks

import numpy
from numpy import dot
from math import sqrt