Iron Yard Homework, Week 1

input_statistics.rb

#!/usr/bin/env ruby

# Need the ability to determine if input text is really just a number. This
# will return a simple true/false
def is_number?(f)
  begin
    Float(f)
    return true
  rescue
    return false
  end
end

# Because a lot of white text causes eyes to bleed, I want the ability to color
# text that I'm printing
class String
  def colorize(color_code)
    "\e[#{color_code}m#{self}\e[0m"
  end
end

# Setup infinite loop that will end when the user enters nothing and hits return.
# This loop will also organize input into two separate arrays so we can mess
# with them later.

puts "Enter text or numbers, and I will statistic them. Press enter when you're finished."
numbers = []
strings = []
while true
  print "Input: ".colorize(36)
  s = gets.chomp!
  if s == ""
    puts "\e[A\e[K" #clear the last input line so I don't have a hanging input
    break
  end
  is_number?(s) ? numbers.push(s.to_f) : strings.push(s)

  # and why should I limit it to one 'mode' versus accepting both?
  if numbers.length > 0 && strings.length > 0
    puts "Don't mix strings and numbers. Please relaunch.".colorize(101)
    exit
  end
end


#puts "Numbers: #{numbers}"
#puts "Strings: #{strings}"

if numbers.length > 0
  puts ""
  puts "Number Statistics".colorize(31)
  puts "==================================".colorize(31)

  # Determine the sum of the numbers
  sumnum = 0.0
  numbers.each { |num| sumnum += num }
  print "Sum of numbers: ".colorize(33)
  puts "#{sumnum}"

  # Determine the average of the numbers
  averagenum = (sumnum / (numbers.length))
  print "Average of numbers: ".colorize(33)
  puts "#{averagenum}"

  # Determine the standard deviation of the numbers
  standarddev = 0.0
  variances = []
  numbers.each { |n| variances.push((n - averagenum)**2.0) }
  variancessum = 0.0
  variances.each { |n| variancessum += n }
  #puts "Variances: #{variances}"
  #puts "Variance Sum: #{variancessum}"
  variance = variancessum / variances.length
  standarddev = Math.sqrt(variance)
  print "Population standard deviation: ".colorize(33)
  puts "#{standarddev}"

  # Determine the median number
  numbers.sort!
  print "Median number: ".colorize(33)
  if numbers.length % 2 == 1
    mediannum = numbers[(numbers.length)/2]
  else
    mediannum = (numbers[(numbers.length-1)/2] + numbers[(numbers.length+1)/2]) / 2
  end
  puts "#{mediannum}"
end

if strings.length > 0
  puts ""
  puts "String Statistics".colorize(31)
  puts "==================================".colorize(31)

  # Concatenate the strings into a long string.
  bigassstring = ""
  strings.each { |s| bigassstring.concat(s) }
  print "Concatenated string: ".colorize(33)
  puts "#{bigassstring}"

  # Determine the sum length of all strings.
  sumlength = 0
  strings.each { |s| sumlength += s.length }
  avglength = sumlength / strings.length.to_f
  print "Average length of strings: ".colorize(33)
  puts "#{avglength}"

  # Determine how many times the character e is used in the strings.
  ecount = 0
  strings.each { |s| ecount += s.downcase.count('e') }
  print "Number of times 'e' was used in all strings: ".colorize(33)
  puts "#{ecount}"
end