aneObj.prototype.draw = function() {

  ctx2.save();

  ctx2.globalAlpha = 0.6;

  ctx2.lineWidth = 20;

  ctx2.lineCap = "round";

  ctx2.stokeStyle = "purple";

for (var i = 0; i < this.num; i++) {

ctx2.beginPath();

ctx2.moveTo(this.x[i], canHeight)

ctx2.lineTo(this.x[i], canHeight - this.len[i])

ctx2.stroke();

};

ctx2.restore();

};