healing.rb

#!/usr/bin/ruby

def random2(x)
  rand(0...x)
end

def roll_dice(n,d)
  r = 0
  for i in 1..n
    r += 1 + random2(d)
  end
  return r
end

def div_rand_round(n, d)
  rem = n%d
  q = n/d
  if rem != 0 && random2(d) < rem
    q += 1
  end
  return q
end

def skill_rdiv(invo, n, d)
  div_rand_round(invo*n*256, d*256)
end

def do_ability(mon_type, same_species, invo)
  pow = 10 + skill_rdiv(invo, 1, 3)
  cast_healing(mon_type, same_species, pow, invo)
end

def cast_healing(mon_type, same_species, pow, invo)
  healed = pow + roll_dice(2, pow) - 2
  can_pacify_monster(mon_type, same_species, healed, invo)
end

def can_pacify_monster(mon_type, same_species, healed, invo)
  factor = 1
  divisor = 3

  case mon_type
    when :animal
      factor = 3
    when :undead
      divisor = 4
    when :demon
      divisor = 5
    when :holy
      divisor = 2
  end

  factor = 2 if same_species

  factor * random2( ((invo*healed)+healed)/divisor )
end

def prob(n, mon, same_species, invo)
  hist = []
  n.times do
    h = do_ability(mon, same_species, invo)
    hist[h] = 0 unless hist[h]
    hist[h] += 1
  end

  for i in 0...hist.size
    hist[i] = 0 unless hist[i]
  end

  p = []
  for i in 0...hist.size
    p[i] = 0
    for j in 0...i
      p[i] += hist[j]
    end

    p[i] = 1 - (1.0*p[i]) / n
  end
  return p
end

def main
  n = 100000
  p1 = prob(n, :animal, false, 27)
  p2 = prob(n, :demon,  false, 27)
  p3 = prob(n, :undead, false, 27)
  p4 = prob(n, :other,  false, 27)

  size = [p1.size, p2.size, p3.size, p4.size].max

  for i in 0...size
    data = [i, p1[i], p2[i], p3[i], p4[i]]
    for j in 0...data.size
      data[j] = 0 unless data[j]
    end
    print "%d %.5f %.5f %.5f %.5f \n" % data
  end
end

main