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- =====
- What it is
- =====
-
- Lyapunov is a program to calculate maps of Lyapunov space, using a
- function originally posted to alt.fractals by Ed Kubaitis. For more
- information on Lyapunov space, see the September 1991 issue of
- Scientific American. While I don't have any way of checking whether
- or not the output of this program is, in fact, mathematically correct,
- it does *look* reasonable; if you discover any errors in this program,
- please send corrections to me.
-
- ====
- Terms and Conditions
- ====
-
- This program and documentation are Copyright 1991, Garrett A. Wollman.
- This program may be modified and distributed for any purpose and
- without fee, provided that this notice remains on all such copies
- unaltered. Binary distributions not including this document are
- prohibited. Modified versions must be marked with the name of the
- modifier and the date of modification.
-
- Under no circumstances shall Garrett A. Wollman or the University of
- Vermont and State Agricultural College be held liable for any damages
- resulting from the use or misuse of this program, whether the author
- is aware of such possibility or not. This program is warranted solely
- to occupy disk space.
-
- ====
- How to use it
- ====
-
- lyapunov generates your choice of PGM or PBM files. If you want to
- actually *look* at the output, you will need a program which can deal
- with this file format; such programs include `xv' (which is the
- program that I use) and Jef Poskanzer's PBMPLUS toolkit.
-
- lyapunov's command line syntax is as follows:
-
- lyapunov [-r rows] [-c cols] [-v program] [-p] [-t]
- [-# processors] [-o file] [-m minLya] [-d Dwell] [-s Settle]
- [-g initGuess] [-5] amin amax bmin bmax bits
-
- where:
-
- [-r rows]
- [-c cols]
- These two flags set the shape of the output image (default 512x512).
-
- [-v program]
- When this flag is specified, output is piped through `program'.
-
- [-p]
- This flag tells the coloring function that you are interested in the
- positive, rather than negative, lyapunov exponents.
-
- [-t]
- This flag turns off the RAWBITS format in the output; it is only
- really useflu for debugging.
-
- [-# processors]
- This flag, on versions that support it, causes the calculation to run
- row-parallel on processors processors. Currently, only Silicon
- Graphics machines are supported.
-
- [-o file]
- Sends the output to `file' instead of standard output. This option
- and `-v' are mutually exclusive.
-
- [-l colormap]
- Use the specified Fractint-style `.map' file instead of the default
- grey.
-
- [-m minLya]
- Tell the coloring routine that minLya is the minimum expected Lyapunov
- exponent (default -5). Values below minLya are clamped to minLya.
-
- [-d Dwell]
- Set the Dwell value (default 2000).
-
- [-s Settle]
- Set the Settle value (default 600).
-
- [-g initGuess]
- Set the starting value for `x'.
-
- [-5]
- This flag turns on PGM (as opposed to PPM) output format; any
- colormap loaded with `-l' is ignored.
-
- amin
- amax
- bmin
- bmax
- The range for `a' and `b' to be calculated. This region is mapped
- onto the *first* quadrant (opposite from the way the rows and columns
- are numbered). See the code for more details.
-
- bits
- A string of 'a's and 'b's to be used as the seed for the Markus
- vector.
-
- ====
- Compiling
- ====
-
- Just look through the Makefile; it's quite self-explanatory. If you
- add support for another CPU or make the program faster, please send me
- the changes!
-
- ====
- Author
- ====
-
- Garrett A. Wollman
- wollman@UVM.EDU
- uvm-gen!wollman
-
- University of Vermont, Division of Engineering, Mathematics, and
- Business Administration, Computer Facility.
-
-