Di Wen ifyouseewendy

ifyouseewendy / multi_level_page_table.rb

Last active December 5, 2015 10:47

Code work on Multi-level Page Tables, from Chap20, Operating Systems - Three Easy Pieces

	class MultiLevelPageTable
	PAGE_DIRECTORY_BASE_REGISTER = 108

	# Save all intermedial state in binary string
	attr_reader :pages, :virtual_address,
	:page_directory_index, :page_table_index, :offset,
	:page_directory, :page_directory_entry, :page_frame_number,
	:page_table, :page_table_entry, :physical_frame_number,
	:physical_address, :value

ifyouseewendy / distinct_file_logger.rb

Created December 10, 2015 14:56

Log to different files based on logging level using Ruby logger

	require 'logger'

	# Examples
	#
	# logger = DistinctFileLogger.new(STDOUT)
	# logger.set_error_path('/Users/wendi/tmp/logger/error.log')

	# logger.info "processing: 1/10"
	# logger.info "processing: 2/10"
	# logger.info "processing: 3/10"

ifyouseewendy / thread_pool.rb

Created December 30, 2015 11:45

	require 'thread'

	QUEUE_SIZE = 2
	POOL_SIZE = 5

	queue = SizedQueue.new(QUEUE_SIZE)

	producers = POOL_SIZE.times.map do
	Thread.new do
	item = rand(10)

ifyouseewendy / pg.rake

Last active January 4, 2016 14:56 — forked from hopsoft/db.rake

Rails rake tasks for dump & restore of PostgreSQL databases

	# lib/tasks/pg.rake
	namespace :pg do
	desc "Dumps the database to backups"
	task :dump => :environment do
	cmd = nil
	with_config do \|app, host, db, user\|
	cmd = "pg_dump -h #{host} -d #{db} -U #{user} -Ft -v -c -f #{Rails.root}/public/resources/duoduo/db_backup/#{Time.now.strftime("%Y%m%d%H%M%S")}_#{db}.tar"
	end
	puts cmd
	exec cmd

ifyouseewendy / flatten_a_nesting_array.rb

Created March 14, 2016 07:17

Flatten an array of arbitrarily nested arrays of integers into a flat array of integers. e.g. [[1,2,[3]],4] -> [1,2,3,4].

	# In Ruby, we can just use Array#flatten
	#
	# def flatten(array)
	# array.flatten
	# end

	# In case you want a manmade version
	def flatten(array)
	array.reduce([]) do \|res, element\|
	Array === element ? res += flatten(element) : res << element

ifyouseewendy / redis_client_ip.rb

Last active May 25, 2016 10:16

Get client ips of redis connection.

	#!/usr/bin/env ruby

	# Usage
	#
	# echo 'client list' \| redis-cli -h $HOST -p $PORT \| ./redis_client_ip.rb
	#
	# Reference
	#
	# http://www.jstorimer.com/blogs/workingwithcode/7766125-writing-ruby-scripts-that-respect-pipelines
	# http://redis.io/commands/client-list

ifyouseewendy / intro_to_elm.elm

Created July 23, 2016 15:51

Demo code from Richard Feldman's https://www.youtube.com/results?search_query=introduction+to+elm

	import Html exposing (..)
	import Html.Attributes exposing (..)
	import Html.Events exposing (..)
	import Html.App as Html

	-- model

	type alias Model =
	{
	shelves : Int,

ifyouseewendy / boilerplate.elm

Created November 28, 2016 14:44

ifyouseewendy / max_heap.rb

Created November 29, 2016 02:25

	# Use a max heap to sort an array
	def heap_sort!(array) # Use ! to represent inplace
	# setup
	n = array.length
	array.unshift nil

	# build
	(n/2).downto(1) do \|k\|
	sink(array, k, n)
	end

ifyouseewendy / index.html

Created March 19, 2017 16:03

Tic Tac Toe