From jacobson@math-cs.cns.uni.edu Thu Oct 24 18:11:09 2002
Date: Thu, 24 Oct 2002 18:09:13 -0500 (CDT)
From: Mark Jacobson <jacobson@math-cs.cns.uni.edu>
To: 810-061-01@uni.edu, 810-061-02@uni.edu
Subject: The pauses between creating new Vehicles in Lane class...

Hi 061 students,

    We will start on chapters 6 and 7 tommorrow in class.  If you have
not purchased the chapters 6, 7 and 8 packet, you probably want to do
that very soon.  The computer science secretary is on vacation tommorrow
(Friday) but there will be a student assistant in the office part of the
time, or you can see me.  They cost $2.10 total for the 65-70 pages of
the Williams College textbook.

    Here is a suggestion for the pause you build into the Lane class.
Obviously, the pause must be bigger or longer for SLOW lanes than it
is for Lanes that are for fast cars.

	public void run()
        {
           double pauseAmount = Math.abs(12000 / velocity);

        // Loop until the program stops.
	   while ( true )

   So if the velocity for the Lane is 4, we have pause of  3000,
                                   if 3,         pause is  4000,
                                   if 2,         pause is  6000,
                                   if 1,         pause is 12000
                                   if 1.5,       pause is  8000

   So my slowest car Lane pauses 12000 milliseconds or about 12 seconds
     before it creates the next new Vehicle object and has it pull on to
     the interstate.

   The reason that I use Math.abs() above, is because a negative
     velocity (not required) that moves the cars from right to left,
     would give a negative quotient.

   Math.abs( 12000 / velocity ) would become
   Math.abs( -6000 ) is the velocity is -2, but the absolute value
                                            of -6000 is 6000.

   Math.abs( -1000 ) is 1000
   Math.abs( 12000 ) is 12000

   The absolute value of -5 is 5.  Math.abs(-5) equals 5

   Mark