======================================================================= CHAOS DEMONSTRATIONS PC Version 3.2 (c) 1998 by J. C. Sprott University of Wisconsin, Madison, WI 53706 sprott@juno.physics.wisc.edu http://sprott.physics.wisc.edu/ ======================================================================= Starting the Program To start the program, place the diskette in drive A, and from the A> prompt, type CHAOS and then press . To activate the museum mode, instead type CHAOS R and then press . Overview CHAOS DEMONSTRATIONS is a collection of twenty-six demonstrations illustrating chaos in physical and biological systems. The goal of the program is to encourage an appreciation of the complexity and beauty of even simple systems, not only for the professional scientist, but also for the interested nonspecialist. The demonstrations can be appreciated on many different levels, from the forefront of research in nonlinear dynamics to pure art. They can be used by an instructor in the classroom, by individual students as a tutorial, or as a display in a museum. You can sit back and watch the demonstrations cycle through an automatic sequence or take control and examine in detail the effect of varying the parameters. All the commands are by single keystrokes or single clicks of a mouse. The program is written to make it easy for you to move from one thing to another. It is accompanied by a graded multiple-choice quiz during which you may review the appropriate demonstration. Computer System Your computer system and hardware configuration should be a PC computer with the following features: 1. CGA, HGA, MCGA, EGA, or VGA graphics 2. Minimum memory of 384K 3. DOS 3.0 or higher 4. Math coprocessor (recommended) 5. Mouse (optional) 6. Printer (recommended) Customization and Automation You can customize or automate the operation by instead typing CHAOS, a space, and a command string containing up to 127 characters representing a sequence of keystrokes to be executed automatically when the program begins. This string may contain single-digit numbers that will cause a delay for a corresponding number of seconds. For example, typing CHAOS A5XB5XC5X at the DOS prompt will cycle through the first three demonstrations, spending five seconds on each. You can produce a longer delay by using multiple digits (e.g., 99 gives an eighteen- second delay). You can display text embedded in quotes. Try a command such as CHAOS "Let's look at the Lorenz attractor..."3G. You can execute DOS commands or user-supplied .BAT, .EXE, or .COM files by embedding them in the command string enclosed within brackets [], but external commands require that COMMAND.COM be in the current path on the disk. You can also save the output of a calculation to a disk file by putting a filename in braces {} on the command line. For example, CHAOS G{LORENZ.DAT} will save the Lorenz attractor data to the file LORENZ.DAT for more detailed analysis by the companion program, CHAOS DATA ANALYZER (J. C. Sprott and G. Rowlands, Physics Academic Software, 1992). To save the output of the most recently viewed demonstration, place the filename in braces as the first (or only) item in the command string, such as CHAOS {RECENT.DAT}. Several other special commands are supported as follows: - waits until is pressed ; dissolves the screen display ? initiates the help feature $ displays the disk directory @ displays the program logo ! initiates the quiz program % executes commands in AUTO.TXT ^ prints the screen . returns to DOS You can cycle backward through the parameters, views, graphic modes, and colors by holding down the key or by using lower- case letters in the automatic command sequence. The <+> and <-> keys change the color palette if your hardware supports it. Placing an R at the end of the command string causes the commands to repeat indefinitely. The special command CHAOS R (equivalent to CHAOS %R) activates an unattended museum-mode of operation. Other possibilities such as CHAOS !5X5R give interesting results. You can keep a record of museum use with a command such as CHAOS {USE.LOG}R. When in the museum mode, the demonstrations cycle automatically with the parameters stepped through a range of values. You can interrupt automatic operation by pressing any key or mouse button, but the cycle will resume automatically after 45 seconds of keyboard and mouse inactivity. You can single-step through the automatic sequence using the key. To exit the automatic mode, press and then release these keys and quickly press . The diskette may be removed from the drive after the program has begun cycling. The commands performed in museum mode are recorded in a file called AUTO.TXT, which can be modified with any word processor that will read and write ASCII files. You can cause the program to take its commands from a different file that you provide by starting CHAOS DEMONSTRATIONS with a command such as CHAOS (MYSCRIPT.TXT). The explanations in EXPLAIN.TXT can be edited, as can the quiz questions in QUIZ.TXT, provided the format is followed exactly. (In QUIZ.TXT, always enter the correct answer as choice A.) Current information on the latest version of the program and other developments are available on the World Wide Web at http://sprott.physics.wisc.edu/chaos.htm.