// Learning Processing
  // Daniel Shiffman
  // http://www.learningprocessing.com
  
  // Example 13-3: Probabilities
  
  void setup() {
    size(200,200);
    background(255);
    smooth();
    noStroke();
  }
  
  void draw() {
    
    // Probabilities for 3 different cases
    // These need to add up to 100%!
    float red_prob = 0.60;   // 60% chance of red color
    float green_prob = 0.10; // 10% chance of green color
    float blue_prob = 0.30;  // 30% chance of blue color
    
    // Pick a random number between 0 and 1
    float num = random(1);  
    
    // If random number is less than .6
    if (num < red_prob) {
      fill(255,53,2,150);
    // If random number is between .6 and .7
    } else if (num < green_prob + red_prob) {
      fill(156,255,28,150);
    // All other cases (i.e. between .7 and 1.0)
    } else {
      fill(10,52,178,150);
    }
    
    // Draw ellipse
    ellipse(random(width),random(height),64,64);
  }