leandromoreira

Image = imread('Cameraman256.bmp');
Frequency = zeros(256);
Samples = 256 * 256;

for i = 1:256
    for j = 1:256
        % convert 0-255 to index-wise
        IntensityIndex = Image(i,j) + 1; 
        Frequency(IntensityIndex) = Frequency(IntensityIndex) + 1;
    end

leandromoreira

% it creates a simple gray image (4x4)
I = [255, 255, 30, 100 
    255, 50, 90, 20 
    70, 70, 20, 10 
    100, 20, 10, 0];
% it converts it to grayscale
I = mat2gray(I);
% shows it 
imshow(I);

leandromoreira

// This post will briefly explain (omiting, skipping some parts) in code what is 
// Functor, Pointed Functor, Monad and Applicative Functor. Maybe by reading the
// code you will easily grasp these functional concepts.

// if you only want to run this code go to:
// https://jsfiddle.net/leandromoreira/buq5mnyk/
// or https://gist.github.com/leandromoreira/9504733c7f8c6361c46270ea953d8409

// This code requires you to have require.js loaded (or you can load ramda instead :P)
requirejs.config({

leandromoreira

var a = []; document.onkeyup=function(e){a+=[(e||self.event).keyCode-37]  ; if (/113302022928/.test(a)) { alert('Konami Code'); a = ""}}

leandromoreira

# creating an amazon machine
docker-machine create --driver amazonec2 --amazonec2-access-key XXX --amazonec2-secret-key "xxxxx" --amazonec2-vpc-id vpc-xxx --amazonec2-zone Y amazon
# creating a digital ocean machine
docker-machine create --driver digitalocean --digitalocean-access-token=XXX do

# let's take note of our ip
docker-machine ip amazon

# let's deploy our application
docker-machine up

leandromoreira

# we'll create a "machine" called dev on virtualbox
docker-machine create --driver virtualbox dev
# let's use this machine
eval "$(docker-machine env dev)"
# let's take note of our docker-ip
docker-machine ip dev
# let's run this app
docker-compose up
# now go to your browser and type ip :) it should show something

leandromoreira

# we'll use 2 processors/core
worker_processes 2;
# we set a new limit for open files for our workers
worker_rlimit_nofile 100000;

# we define how we're going to work 
events {
  # for each worker we'll handle 4000 requests (enquee them)
  worker_connections  4000;
  # we'll accept multiple

leandromoreira

# we'll build our container from an existent image :)
FROM nginx
# for some reason we need to create this folder 
RUN mkdir -p /var/lib/nginx/proxy
# copy our app config to nginx
COPY sites-enabled/myapp.conf /etc/nginx/nginx.conf

leandromoreira

# we'll call our web app of web
web:
  # it'll build this container based the docker file ./Dockerfile
  build: .
  # it'll run this command to star the server
  command: bash -c "rm -f tmp/pids/server.pid || true && bundle exec rails s -p 3000 -b '0.0.0.0'"
  # it'll export the port 3000
  ports:
    - "3000:3000"
  # it links to db container (on mongoid.yaml at rail's config we say host: db:27017 it's linked)

leandromoreira

# we'll use an existent image which already have ruby installed
FROM ruby:2.3.0
# creating our app folder
RUN mkdir /myapp
# move to this folder
WORKDIR /myapp
# move the Gemfile to our app's root folder
ADD Gemfile /myapp/Gemfile
# move the Gemfile.lock too
ADD Gemfile.lock /myapp/Gemfile.lock