hellerbarde

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

willurd

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000

rxaviers

People

:bowtie:	😄 :smile:	😆 :laughing:
😊 :blush:	😃 :smiley:	☺️ :relaxed:
😏 :smirk:	😍 :heart_eyes:	😘 :kissing_heart:
😚 :kissing_closed_eyes:	😳 :flushed:	😌 :relieved:
😆 :satisfied:	😁 :grin:	😉 :wink:
😜 :stuck_out_tongue_winking_eye:	😝 :stuck_out_tongue_closed_eyes:	😀 :grinning:
😗 :kissing:	😙 :kissing_smiling_eyes:	😛 :stuck_out_tongue:

soheilhy

Virtual Hosts on nginx (CSC309)

When hosting our web applications, we often have one public IP address (i.e., an IP address visible to the outside world) using which we want to host multiple web apps. For example, one may wants to host three different web apps respectively for example1.com, example2.com, and example1.com/images on the same machine using a single IP address.

How can we do that? Well, the good news is Internet browsers

patriciogonzalezvivo

Please consider using http://lygia.xyz instead of copy/pasting this functions. It expand suport for voronoi, voronoise, fbm, noise, worley, noise, derivatives and much more, through simple file dependencies. Take a look to https://github.com/patriciogonzalezvivo/lygia/tree/main/generative

Generic 1,2,3 Noise

float rand(float n){return fract(sin(n) * 43758.5453123);}

float noise(float p){
	float fl = floor(p);
  float fc = fract(p);

eatonphil

/**
 * This are a collection of examples for C 201.
 * These combine concepts you may or may not be
 * familiar with and are especially useful for
 * students new to C. There is a lot of really
 * cool stuff you can do in C without any cool
 * languages.
 * 
 * This is file in particular is an introduction
 * to fun function usage in C.

denilsonsa

#
# ███╗   ███╗ ██████╗ ██╗   ██╗███████╗██████╗     ████████╗ ██████╗
# ████╗ ████║██╔═══██╗██║   ██║██╔════╝██╔══██╗    ╚══██╔══╝██╔═══██╗
# ██╔████╔██║██║   ██║██║   ██║█████╗  ██║  ██║       ██║   ██║   ██║
# ██║╚██╔╝██║██║   ██║╚██╗ ██╔╝██╔══╝  ██║  ██║       ██║   ██║   ██║
# ██║ ╚═╝ ██║╚██████╔╝ ╚████╔╝ ███████╗██████╔╝       ██║   ╚██████╔╝
# ╚═╝     ╚═╝ ╚═════╝   ╚═══╝  ╚══════╝╚═════╝        ╚═╝    ╚═════╝
#
# ╔═════════════════════════════════════════════════════════════════╗
# ║      https://github.com/denilsonsa/udev-joystick-blacklist      ║

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:

abstractalgo

Gamma, gamut, tone mapping, color, sRGB

sRGB learning curve
https://gamedevdaily.io/the-srgb-learning-curve-773b7f68cf7a#.y9sitvhmm

Color Math
http://www.essentialmath.com/GDC2015/VanVerth_Jim_DoingMathwRGB.pdf

The Importance of Terminology and sRGB Uncertainty
http://colour-science.org/posts/the-importance-of-terminology-and-srgb-uncertainty/

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?