Dear DECUS Member,

	this diskette contains five tasks.APFEL1 ... APFEL4 are for 
	experimental purposes only.In APFELM all functions tried up to
	now are included.
	The tasks and all subroutines needed are written in FORTRAN_77.
	They work well with P/OS V2.0A,later releases are supposed to
	function too.All sources are included. 
	To start any of the tasks you must first install the CORE graphic
	cluster-library and,if you intend to use the playback facility,
	install the file-read-task (CGLGRT).All preliminary action needed
	you can find in the indirect command-file APFELMRUN.CMD.

	A typical set of start-parameters for the task APFELM is

				 X = -2.0
				 Y = -2.0
		   	    Window = 5.0
	       		Iterations = 50
	       		Resolution = 5

	When you use the Graphic-Microscope the cursor position is the
	origin of a new picture.You can change the origin with the four
	Cursor-Keys and select a specific origin with the Select-Key.
	To continue with a new frame you have to press the Resume-Key.

	When you intent to save a picture on disk be sure to have enough
	space.The disk-space used for GIDIS-Metafiles is enormous.

	
					Aachen,December 1985
					    R.J.Wilden
	Revision A:
	Points in the Mandelbrot set often (always?) enter cycles of values
	and thus do not exceed a norm of 2. The program in the directory
	[APFEL] attempts to detect these cycles and terminate computation
	early. The result can be a great increase in the speed of evaluating
	points in the Mandelbrot set (especially with iteration counts in
	the few-thousand range). The original files are in directory [APFELO]
	on the disk. Cycle detection is not perfect as only a few numbers
	are saved, but it works to speed up some test plots. Routine 
	CHAOS4.FTN is the major site of modifications. The analysis is due
	to some folks who used it in an Amiga-based Mandelbrot explorer; I
	only tried it here.
		Glenn Everhart