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- TIERRA UPDATE:
- (Version 3.11 now available, FTP site reorganized, New Tools, Bug Fixes,
- Genebank Verification, Garbage Collection, New Genomes, Mneumonics
- Shortened, Virtual Extraction, DEC Grant, Sex)
-
- This message contains:
-
- 1) Availability of Tierra V3.11 source code
- a) by ftp
- b) by snail mail on disk
- 2) FTP Site Reorganized
- 2) New Tools
- 3) Bug Fixes
- 4) Genebank Verification
- 5) Garbage Collection
- 6) New genomes distributed
- 7) Opcode mneumonics limited to six characters
- 8) Virtual Extraction
- 9) Grant from Digital Equipment Corporation
- 10) Future Sex
-
- 1) Availability of Tierra V3.11 source code
-
- a) by ftp
-
- The V3.11 source code, the source code, and DOS executables of all tools
- is available now. If you use the software, be sure to pick up new versions
- soon from the ftp site. The source in the ftp site will be replace on a
- roughly monthly or bi-monthly basis.
-
- The complete source code and DOS executables are available by anonymous
- ftp at:
-
- tierra.slhs.udel.edu [128.175.41.34] and
- life.slhs.udel.edu [128.175.41.33]
-
- in the directories: DOS/, almond/, beagle/, doc/, and tierra/.
-
- To get it, ftp to tierra or life, log in as user "anonymous" and give your
- email address (eg. tom@udel.edu) as a password. Be sure to transfer binaries
- in binary mode (it is safe to transfer everything in binary mode).
- Each directory contains a compressed tar file (filename.tar.Z) and a SRC
- directory that contains all the files in raw ascii format. You can just
- pick up the .tar.Z files, and they will expand into the complete directory
- strucutre with the following commands:
-
- uncompress tierra.tar.Z
- tar oxvf tierra.tar
-
- b) by snail mail on disk
-
- If you do not have ftp access you may obtain everything on DOS disks
- by making a check for $65 (US dollars drawn on a US bank) payable to
- Virtual Life. Specify 3.5" or 5.25" disks. Send the check to one of the
- following addresses:
-
- Tom Ray (January through August)
- Santa Fe Institute
- 1660 Old Pecos Trail
- Suite A
- Santa Fe, NM 87501
-
- Virtual Life (September through December)
- P.O. Box 625
- Newark, Delaware 19715
-
- The DOS disks contain everything but ALmond. They include DOS
- executables, source code and documentation. The DOS disks include an easy
- installation program. This is the same source and executables available in
- the ftp site. If you have ftp access, there is no need to buy the disks.
-
- 2) New Tools
-
- Several new (and some old) tools, developed by Dan Pirone and Tom Ray,
- are now fully documented and available in the ftp site:
-
- rnd_inst - A tool for altering the physics of the system by randomly mapping
- opcodes to instructions, with some optional restrictions on hamming
- distances between pairs of instructions. The output is an opcode.map
- file.
-
- probe - A tool for surveying the genebank, with various optional selection
- criteria (a new tool, but proving very useful).
-
- tieout - A tool for generating x,y data from the tierra.log file. This is
- used on a regular basis to generate graphics of size of creatures over
- time during a run.
-
- diverse - A tool that reads the birth and death records (break.X files) output
- by Tierra and transforms them into various measures of diversity, for
- graphical or other analysis.
-
- beagle - A DOS only tool which provides a variety of graphical displays of
- the output from the Tierra simulator. It is used after a run, and is
- highly recommended as a tool for analyzing the results of a run.
-
- run_info - A function of the beagle program, also available as a stand-alone,
- due to its hunger for memory.
-
- fragment - A function of the beagle program, also available as a stand-alone,
- due to its hunger for memory.
-
- ALmond - A UNIX only tool which runs as a separate process on the same or a
- different machine. ALmond establishes socket communications with a
- running Tierra, and provides a color display of the spatial distribution
- of the creatures in the soup, showing all births and deaths. This tool
- has some new functions: you can view the positions of the instruction
- pointers, or the activity of the moviab instruction.
-
- 3) Bug Fixes
-
- histograms - Version 3.1 included some obvious errors in the histogram
- display. These have been corrected.
-
- moviab - This instruction allows creatures to alter their own genome by
- writing on themselves. Before V3.11, the genebanker did not watch
- for genetic changes occurring in this manner. This created observational
- errors comparable to the ploidy bug corrected in V3.1. The genebanker
- now catalogs genetic change by this mechanism. It is believed that
- the genebanker is now fully reliable (see below).
-
- chmod - The chmod function was supposed to return a value, but did not.
- This had the consequence that a flag was set every time a creature
- allocated space for a daughter, and these were recorded with the
- demography data associated with each creature. This has been corrected.
-
- arg r option - The arg r option (replace or add) was not working, but
- is now.
-
- 4) Genebank Verification
-
- Error checking code has been added which completely verifies that the
- distribution of genotypes in the soup matches that reflected in the genebank,
- and that various counts are internally consistent within the genebank.
-
- 5) Garbage Collection
-
- Routines have been added which clean-up the genebank once per million
- exectued instructions. Among other things, once a size class is extinct,
- all genomes of that size are eliminated from RAM. Permanent genomes are first
- saved to disk.
-
- 6) New genomes distributed
-
- Many new genomes were first distributed with V3.1, but they were not
- mentioned in the announcement. These are the genomes of most of the
- creatures described in the publications and videos: parasites,
- hyper-parasites, social creatures, cheaters, etc.
-
- 7) Opcode mneumonics limited to six characters
-
- To facilitate their display by the Beagle tools, the opcode mneumonics
- have been limited to six characters. This affects push_ax, push_bx, push_cx,
- push_dx, and mov_iab. These have been changed to pushax, pushbx, pushcx,
- pushdx and moviab. This means that old ascii genome files can not be read
- by the new tools. It does not affect binary genome files. Old binary files
- will be mapped to the new names when they are converted to ascii by the new
- software. All the ascii .tie files are redistributed in the new format.
-
- 8) Virtual Extraction
-
- When a new genotype crosses one of the thresholds (SavThrMem or
- SavThrPop) its name becomes permanent and it is ``extracted'' (written to
- disk). This event is noted in the user interface and in the tierra.log
- file like: ex = 0079aaa @ 13
- The new feature is that when a genotype goes extinct, then reappears and
- crosses the thresholds again, it experiences a ``virtual extraction'',
- which means that it is not written to disk (since it is already there),
- but the extraction event is written to the interface and the tierra.log
- file like: ex = 0079aaa @ 13 v
- This was done to facilitate the use of the tieout tool with cumulative
- genebanks, but it results in nicer extraction data in other senses as well.
-
- 9) Grant from Digital Equipment Corporation
-
- The Semiconductor Engineering Group of Digital Equipment Corporation has
- donated two fully loaded DS5000 workstations to the Santa Fe Institute as a
- part of a grant to Tom Ray titled: ``Computer Architectures for the Natural
- Evolution of Machine Codes''. These two machines will be the primary platform
- for Tierra research and development in the near future.
-
- 10) Future Sex
-
- Walter Tackett (tackett@ipld01.hac.com or tackett@priam.usc.edu)
- has implemented haploid sex based on cross-over (a random cross-over point
- used by the moviab instruction) in his private copy of Tierra V3.0. The
- methodology used by Tackett has been implemented in the Santa Fe verison of
- Tierra. It will be released when it has undergone more testing to verify its
- functions.
-