lexicon.txt

exm for Experiments with MATLAB (by Cleve Moler in 2008), 这本书是关于MATLAB的教材

LIFE LEXICON
  Release 25, 2006 February 28
  ASCII version

INTRODUCTION
  This is a lexicon of terms relating to John Horton Conway's
Game of Life.  It is also available in single-page and multipage
HTML versions.
  This lexicon was compiled by Stephen A. Silver - see
below for additional credits.  I can be contacted at
life(at)argentum.freeserve.co.uk.
  The latest versions of this lexicon (both HTML and ASCII)
should be available from the Life Lexicon Home Page at
http://www.argentum.freeserve.co.uk/lex_home.htm.

CREDITS
  The largest single source for the early versions of this lexicon was
a glossary compiled by Alan Hensel "with indispensable help from John
Conway, Dean Hickerson, David Bell, Bill Gosper, Bob Wainwright, Noam
Elkies, Nathan Thompson, Harold McIntosh, and Dan Hoey".
  Other sources include the works listed in the bibliography at the
end of this lexicon, as well as pattern collections by Alan Hensel and
David Bell (and especially Dean Hickerson's file stamp.l in the latter
collection), and the web sites of Mark Niemiec, Paul Callahan, Achim
Flammenkamp, Robert Wainwright and Heinrich Koenig.  Recent releases
also use a lot of information from Dean Hickerson's header to his
1995 stamp file (http://math.ucdavis.edu/~dean/RLE/stamps.html).
  Most of the information on recent results is from the discoverers
themselves.
  The following people all provided useful comments on earlier releases
of this lexicon: David Bell, Nicolay Beluchenko, Johan Bontes, Scot
Ellison, Nick Gotts, Dave Greene, Alan Hensel, Dean Hickerson, Dieter
Leithner, Mark Niemiec, Gabriel Nivasch, Andrzej Okrasinski, Peter Rott,
Tony Smith, Ken Takusagawa, Andrew Trevorrow and Malcolm Tyrrell.
  The format, errors, use of British English and anything else you
might want to complain about are by Stephen Silver.

COPYING
  This lexicon is copyright (C) Stephen Silver, 1997-2005.  It may be
freely copied and/or modified as long as due credit is given.  This
includes not just credit to those who have contributed in some way to
the present version (see above), but also credit to those who have made
any modifications.

LEXICOGRAPHIC ORDER
  I have adopted the following convention: all characters (including
spaces) other than letters and digits are ignored for the purposes of
ordering the entries in this lexicon.  (Many terms are used by some
people as a single word, with or without a hyphen, and by others as two
words.  My convention means that I do not have to list these in two
separate places.  Indeed, I list them only once, choosing whichever
form seems most common or sensible.)  Digits lexicographically precede
letters.

FORMAT
  The format used in the ASCII version of this lexicon is loosely
based on that of the Jargon File.  In particular, the keywords are
enclosed in colons and selected references to them are enclosed in
curly brackets.  The curly brackets will not be of much use unless
you have a programmable text editor, in which case you could program
it to jump from a reference to the corresponding definition when you
hit a certain key.  (The file lifelex.el, which you should have
received with this lexicon, provides such a facility for GNU Emacs.)
If you don't want the curly brackets you can safely remove them with
two find and replace operations, since they are not used for any other
purpose in this file.  The colons are more generally useful.  For
example, a search for ":foo" will take you straight to the definition
of the first word beginning with "foo" (or at least it would if there
were any).
  The diagrams in this lexicon are in a very standard format.  You
should be able to simply copy a pattern, paste it into a new file and
run it in your favourite Life program.  If you use Johan Bontes' Life32,
Mirek Wojtowicz' MCell or Andrew Trevorrow and Tomas Rokicki's Golly
then you can, of course, paste the pattern directly into the Life
program.  If you view this lexicon in GNU Emacs and use lifelex.el then
you should be able to load a pattern into your Life program with a
single keypress, without needing to copy or paste.
  The diagrams use an asterisk to represent a live cell.  If this looks
ugly with the font you use then you can change to O or o with a global
replace.  I have restricted myself to diagrams of size 64x64 or less.
  Most definitions that have a diagram have also some data in brackets
after the keyword.  Oscillators are marked as pn (where n is a positive
integer), meaning that the period is n (p1 indicates a still life).
Wicks are marked in the same way but with the word "wick" added.  For
spaceships the speed (as a fraction of c, the speed of light), the
direction and the period are given.  Fuses are marked with speed and
period and have the word "fuse" added.  Wicks and fuses are infinite in
extent and so have necessarily been truncated, with the ends stabilized
wherever practical.

SCOPE
  This lexicon covers only Conway's Life, and provides no information
about other cellular automata.  David Bell has written articles on
two other interesting cellular automata: HighLife (which is similar
to Life, but has a tiny replicator) and Day & Night (which is very
different, but exhibits many of the same phenomena).  These articles
can be found on his web-site (http://www.canb.auug.org.au/~dbell/).

ERRORS AND OMISSIONS
  If you find any errors (including typos) or serious omissions, then
please let me know.

NAMES
  When deciding whether to use full or abbreviated forms of forenames
I have tried, wherever possible, to follow the usage of the person
concerned.

QUOTE
  Every other author may aspire to praise; the lexicographer can only
hope to escape reproach.  -- Samuel Johnson, 1775

DEDICATION
  This lexicon is dedicated to the memory of Dieter Leithner, who died
on 26 February 1999.

-----------------------------------------------------------------------

:101: (p5)  Found by Achim Flammenkamp in August 1994.  The name was
   suggested by Bill Gosper, noting that the {phase} shown below
   displays the period in binary.
	....**......**....
	...*.*......*.*...
	...*..........*...
	**.*..........*.**
	**.*.*..**..*.*.**
	...*.*.*..*.*.*...
	...*.*.*..*.*.*...
	**.*.*..**..*.*.**
	**.*..........*.**
	...*..........*...
	...*.*......*.*...
	....**......**....

:1-2-3: (p3)  Found by Dave Buckingham, August 1972. This is one of only
   three essentially different p3 {oscillator}s with only three cells in
   the {rotor}.  The others are {stillater} and {cuphook}.
	..**......
	*..*......
	**.*.**...
	.*.*..*...
	.*....*.**
	..***.*.**
	.....*....
	....*.....
	....**....

:1-2-3-4: (p4)  See also {Achim's p4}.
	.....*.....
	....*.*....
	...*.*.*...
	...*...*...
	**.*.*.*.**
	*.*.....*.*
	...*****...
	...........
	.....*.....
	....*.*....
	.....*.....

:14-ner: = {fourteener}

:2 eaters: = {two eaters}

:4-8-12 diamond:  The following {pure glider generator}.
	....****....
	............
	..********..
	............
	************
	............
	..********..
	............
	....****....

:4 boats: (p2)
	...*....
	..*.*...
	.*.**...
	*.*..**.
	.**..*.*
	...**.*.
	...*.*..
	....*...

:4F: = {Fast Forward Force Field}

:Achim's p144: (p144)  This was found (minus the blocks shown below)
   on a cylinder of width 22 by Achim Flammenkamp in July 1994.  Dean
   Hickerson reduced it to a finite form using {figure-8}s the same day.
   The neater finite form shown here - replacing the figure-8s with
   blocks - was found by David Bell in August 1994.  See {factory} for
   a use of this oscillator.
	**........................**
	**........................**
	..................**........
	.................*..*.......
	..................**........
	..............*.............
	.............*.*............
	............*...*...........
	............*..*............
	............................
	............*..*............
	...........*...*............
	............*.*.............
	.............*..............
	........**..................
	.......*..*.................
	........**..................
	**........................**
	**........................**

:Achim's p16: (p16)  Found by Achim Flammenkamp, July 1994.
	.......**....
	.......*.*...
	..*....*.**..
	.**.....*....
	*..*.........
	***..........
	.............
	..........***
	.........*..*
	....*.....**.
	..**.*....*..
	...*.*.......
	....**.......

:Achim's p4: (p4)  Dave Buckingham found this in a less compact form
   (using two halves of {sombreros}) in 1976.  The form shown here was
   found by Achim Flammenkamp in 1988.  The {rotor} is two copies of
   the rotor of {1-2-3-4}, so the oscillator is sometimes called the
   "dual 1-2-3-4".
	..**...**..
	.*..*.*..*.
	.*.**.**.*.
	**.......**
	..*.*.*.*..
	**.......**
	.*.**.**.*.
	.*..*.*..*.
	..**...**..

:Achim's p5: = {pseudo-barberpole}

:Achim's p8: (p8)  Found by Achim Flammenkamp, July 1994.
	.**......
	*........
	.*...*...
	.*...**..
	...*.*...
	..**...*.
	...*...*.
	........*
	......**.

:acorn: (stabilizes at time 5206)  A {methuselah} found by Charles
   Corderman.
	.*.....
	...*...
	**..***

:A for all: (p6)  Found by Dean Hickerson in March 1993.
	....**....
	...*..*...
	...****...
	.*.*..*.*.
	*........*
	*........*
	.*.*..*.*.
	...****...
	...*..*...
	....**....

:against-the-grain grey ship:  A {grey ship} in which the region of
   density 1/2 consists of lines of ON cells lying perpendicular
   to the direction in which the spaceship moves.  See also
   {with-the-grain grey ship}.

:agar:  Any pattern covering the whole plane that is periodic in both
   space and time.  The simplest (nonempty) agar is the {stable} one
   extended by the known {spacefiller}s.  For some more examples see
   {chicken wire}, {houndstooth agar}, {onion rings}, {squaredance}
   and {Venetian blinds}.  Tiling the plane with the pattern O......O
   produces another interesting example: a p6 agar which has a phase of
   {density} 3/4, which is the highest yet obtained for any phase of an
   oscillating pattern.

:aircraft carrier: (p1)  This is the smallest {still life} that has more
   than one {island}.
	**..
	*..*
	..**

:airforce: (p7)  Found by Dave Buckingham in 1972.  The rotor consists
   of two copies of that used in the {burloaferimeter}.
	.......*......
	......*.*.....
	.......*......
	..............
	.....*****....
	....*.....*.**
	...*.**...*.**
	...*.*..*.*...
	**.*...**.*...
	**.*.....*....
	....*****.....
	..............
	......*.......
	.....*.*......
	......*.......

:AK47 reaction:  The following reaction (found by Rich Schroeppel and
   Dave Buckingham) in which a honey farm predecessor, catalysed by
   an eater and a block, reappears at another location 47 generations
   later, having produced a glider and a traffic light.  This is the
   basis of a very small (but {pseudo}) p94 glider gun found by Paul
   Callahan in July 1994, and was in 1990 the basis for the Dean
   Hickerson's construction of the first {true} p94 gun.  (This latter
   gun was enormous, and has now been superseded by comparatively small
   {Herschel loop} guns.)
	.....*....
	....*.*...
	...*...*..
	...*...*..
	...*...*..
	....*.*...
	.....*....
	..........
	..**......
	...*......
	***.....**
	*.......**

:Al Jolson: = {Jolson}

:almosymmetric: (p2)  Found in 1971.
	....*....
	**..*.*..
	*.*......
	.......**
	.*.......
	*......*.
	**.*.*...
	.....*...

:anteater:  A pattern that consumes {ants}.

:antlers: = {moose antlers}

:ants: (p5 wick)  The standard form is shown below.  It is also
   possible for any ant to be displaced by one or two cells relative
   to either or both of its neighbouring ants.  Dean Hickerson found
   {fencepost}s for both ends of this wick in October 1992 and
   February 1993.  See {electric fence}, and also {wickstretcher}.
	**...**...**...**...**...**...**...**...**..
	..**...**...**...**...**...**...**...**...**
	..**...**...**...**...**...**...**...**...**
	**...**...**...**...**...**...**...**...**..

:antstretcher:  Any {wickstretcher} that stretches {ants}.

:anvil:  The following {induction coil}.
	.****.
	*....*
	.***.*
	...*.**

:APPS: (c/5 orthogonally, p30)  An asymmetric {PPS}.  The same as the
   {SPPS}, but with the two halves 15 generations out of phase with one
   another.  Found by Alan Hensel in May 1998.

:ark:  A pair of mutually stabilizing {switch engine}s.  The archetype
   is {Noah's ark}.  The diagram below shows an ark found by Nick Gotts
   that takes until generation 736692 to stabilize, and can therefore be
   considered as a {methuselah}.
	...........................*....
	............................*...
	.............................*..
	............................*...
	...........................*....
	.............................***
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	................................
	**..............................
	..*.............................
	..*.............................
	...****.........................

:arm:  A long extension hanging off from the main body of a {spaceship}
   or {puffer} perpendicular to the direction of travel.