Change percent input to decimal

lib/music_theory/envelope.rb

@@ -3,9 +3,9 @@ class Envelope
 
  def initialize(options = {})
  @duration = options[:duration]
- @attack = options[:attack] # in seconds ex: 0.15
- @sustain = options[:sustain] # percentage ex: 30
- @decay = options[:decay] # percentage ex: 60
+ @attack = options[:attack] # in seconds  ex: 0.15
+ @sustain = options[:sustain] # decimal between 0 and 1 ex: 0.2
+ @decay = options[:decay] # decimal between 0 and 1 ex: 0.6
  @sample_rate = 22050
  @total_frames = @sample_rate * @duration
  end
@@ -18,13 +18,13 @@ def attack_frames
  end
 
  def sustain_frames
- sustain_frames_count = (@total_frames - attack_frames.length) * (@sustain.to_f / 100.0)
+ sustain_frames_count = (@total_frames - attack_frames.length) * @sustain
  sustain_frames = Array.new(sustain_frames_count) { 1 }
  sustain_frames
  end
 
  def decay_frames
- decay_frames_count = (@total_frames - attack_frames.length) * (@decay.to_f / 100.0)
+ decay_frames_count = (@total_frames - attack_frames.length) * @decay
  decay_rate = (1.0 / decay_frames_count)
  decay_frames = Array.new(decay_frames_count){ |index| index * decay_rate }.reverse
  decay_frames
@@ -34,7 +34,7 @@ def envelope_frames
  envelope_frames = attack_frames + sustain_frames + decay_frames
  if envelope_frames.length < @total_frames
  remainder = @total_frames - envelope_frames.length
- filler = Array.new(remainder){ 0 }
+ filler = Array.new(remainder) { 0 }
  envelope_frames += filler
  end
  envelope_frames

test/envelope_test.rb

@@ -7,8 +7,8 @@ def setup
  duration: duration,
  envelope: Envelope.new(duration: duration,
  attack: 0.15,
- sustain: 10,
- decay: 70),
+ sustain: 0.2,
+ decay: 0.6),
  output_file_name: 'delete_me')
  end