code: @Pure
  	public DoubleProperty y1Property() {
  		if (this.p1.y == null) {
  			this.p1.y = new SimpleDoubleProperty(this, MathFXAttributeNames.Y1);
  		}
  		return this.p1.y;
  	}
docs: Replies the property that is the y coordinate of the first segment point.
  
  @return the y1 property.