- (IBAction)panToControlTempo:(UIPanGestureRecognizer *)sender
{
    CGPoint vel = [sender velocityInView:self.view];
    if (vel.x > 0)
    {   // user dragged towards right
    vel.x = 0;
	if (num >= maxNum )
	{
     	  num = maxNum;
	}else{
	  num++;
	}
    }
    else if(vel.x < 0)
    {   // user dragged towards left
    vel.x = 0;
	 if (num <= minNum)
	{
	  num = minNum;
	}else{
	  num--;
	}
    }
    else if(vel.y < 0)
    {   // user dragged towards up
    vel.y = 0;
	if (num >= maxNum )
	{
	  num = maxNum;
	}else{
	  num++;
	}
    }
    else if(vel.y > 0)
    {   // user dragged towards down
    vel.y = 0;
	if (num <= minNum)
	{
	  num = minNum;
	}else{
	  num--;
	}
    }