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#!/bin/bash
###!/usr/bin/python3

#Encode

#Binary [b]
python3 << code
print((lambda s,b: format(int(bytearray(s, "ascii").hex(), 16), b))("Hello friend!", "b"))
code

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http://radio.garden/live/ibiza/costadelmar-radio/

http://radio.garden/live/ibiza/openlab/

http://radio.garden/live/ibiza/beachgrooves-radio/

http://radio.garden/live/palma/fibwi-radio/

http://radio.garden/live/palma/mallorca-sunshine-radio/

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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

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Disabling GNOME Tracker and Other Info

GNOME's tracker is a CPU and privacy hog. There's a pretty good case as to why it's neither useful nor necessary here: http://lduros.net/posts/tracker-sucks-thanks-tracker/

After discovering it chowing 2 cores, I decided to go about disabling it.

Directories

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System λ

The untyped Lambda Calculus

e ::=             terms:
  x               variable
  e e             application
  λ x . e         abstraction

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Latency Comparison Numbers
--------------------------
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

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Colours in terminal

It's a common confusion about terminal colours... Actually we have this:

• plain ascii
• ansi escape codes (16 colour codes with bold/italic and background)
• 256 colour palette (216 colours + 16 ansi + 24 gray) (colors are 24bit)
• 24bit true colour ("888" colours (aka 16 milion))

printf "\x1b[${bg};2;${red};${green};${blue}m\n"

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Advanced Functional Programming with Scala - Notes

Copyright © 2017 Fantasyland Institute of Learning. All rights reserved.

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

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#!/bin/bash
#
# rotate_desktop.sh
#
# Rotates modern Linux desktop screen and input devices to match. Handy for
# convertible notebooks. Call this script from panel launchers, keyboard
# shortcuts, or touch gesture bindings (xSwipe, touchegg, etc.).
#
# Using transformation matrix bits taken from:
#   https://wiki.ubuntu.com/X/InputCoordinateTransformation