sprint.rb

#!/usr/bin/ruby

require 'rubygems'
require 'csv'
require 'rubystats'

def variance(population)
  mean = 0.0
  s = 0.0
  
  population.each_with_index do |x, index|
    delta = x - mean
    mean = mean + (delta / (index+1))
    s += delta * (x - mean)
  end
  return s / population.size
end

def standard_deviation(population)
  Math.sqrt(variance(population))
end

COLORS = %w(red green blue purple burlywood pink)
LEGEND_Y = 0.3

wave_stats = []
waves = ARGV.map{|a| Dir.glob(a) }.flatten
waves.each_with_index do |wave, index|
  csvs = Dir.glob(File.join(wave, '**', '*.csv'))
  estimates = [[]]
  
  csvs.each do |csv|
    clevel = 1
    
    CSV::Reader.parse(File.open(csv, 'rb')) do |row|
      level = row[0].to_i
      next if level == 0
      
      if level > clevel
        estimates[estimates.size-1] = [row[7]]
      elsif level == clevel
        estimates[estimates.size-1] << row[7]
      else
        estimates << [row[7]]
      end
      
      clevel = level
    end
  end
  
  estimates = estimates.flatten.compact.map{|e|e.to_f}.sort

  mean = estimates.inject(0){|m,n| m + n} / estimates.size
  median = estimates[estimates.size/2]
  mode = estimates.inject({}){|m,n| m[n] ||= 0; m[n] += 1; m }.inject{|m,n| n[1] > m[1] ? n : m }[0]
  standard_deviation = standard_deviation(estimates)
  
  # puts "mean: #{mean}"
  # puts "median: #{median}"
  # puts "mode: #{mode}"
  # puts "stdev: #{standard_deviation}"
  
  wave_stats << {
    :estimates => estimates,
    :mean => mean,
    :median => median,
    :mode => mode,
    :stdev => standard_deviation,
    :wave => wave
  }
end

wave_stats.sort{|a,b| a[:stdev] <=> b[:stdev] }.each_with_index do |stat, index|
  puts "x#{index} <- c(#{stat[:estimates].join(',')})"
  puts "y#{index} <- dnorm(x#{index}, mean=#{stat[:mean]}, sd=#{stat[:stdev]})"
  
  if index == 0
    puts "plot(x#{index},y#{index}, xlim=c(0,15), pch=1)"
  else
    puts "points(x#{index},y#{index}, pch=1)"
  end
  
  color = COLORS[index % COLORS.length]
  
  puts "x <- x#{index}"
  puts "curve(dnorm(x, mean=#{stat[:mean]}, sd=#{stat[:stdev]}), add=TRUE, col=\"#{color}\")"
  puts "legend(10,#{LEGEND_Y-(index.to_f/40)}, \"#{stat[:wave]}\", fill=\"#{color}\")"
end