Osazeme Usen osazemeu

Download videos from egghead

Install the React Developer Tools Chrome Extension.
Go to the egghead website, i.e. Getting Started with Redux
Click View -> Developer -> Javascript Console, then the React tab, then the <NextUpLessonList ...> tag.
Click back to the Console tab, then run:

Rails naming conventions

General Ruby conventions

Class names are CamelCase.

Methods and variables are snake_case.

Methods with a ? suffix will return a boolean.

UPDATE a fork of this gist has been used as a starting point for a community-maintained "awesome" list: machine-learning-with-ruby Please look here for the most up-to-date info!

Resources for Machine Learning in Ruby

Gems

liblinear-ruby: Ruby interface to LIBLINEAR using SWIG

CHEAT SHEETS

$ command line ruby cheat sheets

INSTALL

$ gem install rspec

Update and upgrade the system

sudo apt-get update && sudo apt-get upgrade && sudo apt-get dist-upgrade && sudo apt-get autoremove
sudo reboot

Configure timezone

Originally published in June 2008

When hiring Ruby on Rails programmers, knowing the right questions to ask during an interview was a real challenge for me at first. In 30 minutes or less, it's difficult to get a solid read on a candidate's skill set without looking at code they've previously written. And in the corporate/enterprise world, I often don't have access to their previous work.

To ensure we hired competent ruby developers at my last job, I created a list of 15 ruby questions -- a ruby measuring stick if you will -- to select the cream of the crop that walked through our doors.

What to expect

Candidates will typically give you a range of responses based on their experience and personality. So it's up to you to decide the correctness of their answer.

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

	require 'rails_helper'

	RSpec.describe TodosController, :type => :controller do

	describe "GET #index" do
	#describe "POST #create" do
	#describe "GET #show" do
	#describe "PATCH #update" do (or PUT #update)
	#describe "DELETE #destroy" do
	#describe "GET #new" do

	# Thee will be more information here when I share the entire problem space I'm working on, but
	# in short, this is preview material for my second talk in a series called "What Computer Scientists Know".
	# The first talk is on recursion, and goes through several examples., leading up to a problem based
	# on a simple puzzle that initial estimates based on performance of a previous puzzle would take years
	# to solve on modern computers with the techniques shown in Ruby. That sets the stage for improving the
	# performance of that problem with threading, concurrency, and related tuning.
	#
	# The second talk is on threading and concurrency, touching on algorithmic performance as well.
	# Using some knowledge of the problem (board symmetry, illegal moves, etc), we reduce the problem space
	# to about .5% of what we initially thought it was. Still, the initial single threaded solution took more

	# This is a skeleton for testing models including examples of validations, callbacks,
	# scopes, instance & class methods, associations, and more.
	# Pick and choose what you want, as all models don't NEED to be tested at this depth.
	#
	# I'm always eager to hear new tips & suggestions as I'm still new to testing,
	# so if you have any, please share!
	#
	# This skeleton also assumes you're using the following gems:
	#
	# rspec-rails: https://github.com/rspec/rspec-rails