O-I

def get_character(hexnum)
  char = ''
  char << hexnum.to_i(16)
end

O-I

Quicksort

This is an implementation of the quicksort algorithm written in Ruby. Basically, the same code you'll find on Wikibook's entry for quicksort implementations. A gem from the 'Book'.

O-I

Further reading on nil in Ruby & Rails

Ruby: Is nil?

• Lukasz Wrobel demystifies nil in Ruby

Why the id of nil is 4 in Ruby

• An older post by Neeraj Singh on nil's object_id

a World Without Nil

O-I

require 'matrix'

# Input: an array of the n coefficients [a_n, a_n-1,..., a_1] of 
# a univariate polynomial p of degree n ([a_n]x^n + [a_n-1]x^n-1 + ... + a_1)
#
# Output: an array of all n roots of p
#
# Exploits the fact that the eigenvalues of the companion matrix of the
# monic equivalent of p are the roots of p
#

O-I

fizzbuzz :: Int -> [String]
fizzbuzz n = take n $ addNums $ zipWith (++) fizz buzz
  where fizz     = cycle ["", "", "Fizz"]
        buzz     = cycle ["", "", "", "", "Buzz"]
        addNums  = zipWith numOrNot $ map show [1..]
        numOrNot = \ x y -> if null y then x else y

O-I

# Question source: http://codegolf.stackexchange.com/q/8574/12268

# Write an algorithm in any programming language you desire
# that generates n unique randomly-distributed random natural
# numbers (i.e. positive integers, no zero), sum of which is
# equal to t, where t is bigger than or equal to n*(n+1)/2.

# Example: Generate 10 unique random natural numbers, sum of which is equal to 500.

def rand_sum(size, sum)

O-I

require 'open-uri'
require 'dotenv'
require 'json'
require 'pry'

Dotenv.load

# Basic structure of a Guardian API request:

# BASE_URI + endpoint + queries + api-key + params

O-I

# nsect takes an array and optional positive integer n (default is 3)
# and returns the array partitioned into n arrays, (n-1) of which are
# of size i, the nth partition being of size (i-1), i, or (i+1).
# Examples below:

def nsect(arr, n = 3)
  i = (arr.size + 1) / n  
  ans = []  
  (n-1).times do |j|  
     ans << arr[(0+j)*i...(1+j)*i]    

O-I

require 'prime'

def ulam_spiral(n)
  matrix = Array.new(n) { Array.new(n) }
  path = [*1..n*n].reverse
  padding = (n*n).to_s.size
  layer = 0
  until path.empty?
    matrix[layer].map! { |l| l || path.shift }
    matrix = matrix.transpose.reverse

O-I

Here's today's scenario. I'm working on mocking requests to an API to test a Ruby wrapper I've built for it. I have a spec_helper file with several convenience methods that look something like this:

# spec_helper.rb
# snip

def stub_get(path, options = {})
  endpoint = DEFAULT_API_URL + path
  headers  = DEFAULT_HEADERS
 stub_request(:get, endpoint)