Version 3.2 ChessU3 - February 1997

	There have been many changes to basic prompts so be sure to enter
	"H" (Help) at all prompts (following the main file open) to see
	what is new.

	The new, single-function loop detection (repeating games) seems
	fairly foolproof ("L" flag).

	Use the "R" flag to be able to handle games with annotations.
	The annotations will not appear on any games written to the
	line file (LinesU4).

Version 3.1.1 ChessU3 - November 1996

	The main change with this version is the ability to display an
	entire game. Going deeper into the tree, select first option (g)
	then option (d).

	The "lines" file has also been renamed from GamesU4 to LinesU4
	to make it compatible with the new ChessU4. Idiosyncrasies with
	the lines file location and its append status have also been
	ironed out.

ChessU3 is fairly straight-forward to use. Start by trying simple 
defaults. If the "minimum games" number is set higher, you will be more 
apt to zero-in on GM lines by observing the mini-max "Rate." Setting it 
lower will often locate sharp lines and correspondence games.

Once a file has been opened, type (h) for the help screen.

Instructions for using the ChessU3 Tree Searcher
================================================

	- run on a relatively small file with games of a single opening

	- 2000 games can be read but only at a shallow depth; 24 halfmoves
	  are usually accepted by a collection of 500 games provided they
	  represent a single opening. Narrow larger collections with ChessU4
	  or by selecting and printing to a file with your database.

	- halfmove depth determines how deeply the games will be
	  analyzed

	- "minimum games for rating" (second parameter of second prompt)
	  determines the size of a "granule" of games to be rated by
	  mini-max backsolving. An input value of 5 would result in
	  values passed back from +5.00 (good for White) to -5.00 (good
	  for Black). A value of +5.00 would mean that White won 5 out of
	  5 games by following the particular line down to the point
	  where only 5 games were left. Theoretically, if +5.00 were to
	  appear as the "Rate" on move one, it would mean that White had
	  a very good chance of forcing a winning line. (The only
	  exceptions would come from stray, countering variations for
	  Black of less than five games each.)

	- enter H (help) at a candidate's menu prompt for other options

	- Version 3.0 now has mark and jump options. A jump can only be
	  made to a previously marked position and the jump must always
	  be in a backwards direction.

	- ChessU3 can handle roughly 6000 positions or move transitions.
	  If the numbers are exceeded, try reducing the halfmove depth
	  or reduce the size of the collection.

	- ChessU3 creates lines for ChessU4 position searches. Going in
	  the opposite direction, it is also handy to run ChessU4 first,
	  preselecting games across multiple game files for ChessU3.

	- The line file (LinesU4.txt) created by ChessU3 is all set to
	  go for ChessU4 Ver. 3.0.1. Once you have found a good line in
	  ChessU3, save it to LinesU4 and do a backwards-stepping
	  position search (p*) in ChessU4 until you have found a dozen
	  or so similar games to set aside for study.

	- PGN (Portable Game Notation) ASCII chess files work best but
	  ChessU3 may be able to read other formats as well. A test on a
	  few games is a good way to find out.

Repeating Moves: ChessU3 will repeat analysis when it encounters a game
	  with repeating moves. With certain openings--especially at a
	  deep halfmove depth, several repeats and perpetuals may be
	  encountered and other games may interact with the repeating
	  game. ChessU3 breaks such loops (repeats) and displays the game
	  numbers of each pass in groups--separated by a slash (/). If a
	  group contains only a single game number, it is a simple
	  repeat; if various game numbers are shown in one group, it is
	  usually the second to the last game (in a group) which contained
	  the repeat and involved the others.

	  Repeating games can be located (by game number) and investigated
	  with chess reader, ChessU4. Sometimes, if you intend to do
	  multiple studies on a game file, it may be beneficial to
	  manually remove the repeats from games using your editor. This
	  can be done by simply "slicing--out" the repeating moves--since
	  neither ChessU3 nor ChessU4 will object to move number breaks.
	  To preserve the historical integrity of such games, always
	  retitle them "lines" and note the changes made. Example:

	  Header

	     [Event "(LINE) had repeating: (Nf6 18.Bh6 Ne8 19.Be3)"]

	  Notation

             16.Rac1 Qb7 17.Be3 bxc3 20.Nxc3 Bd7 21.Ba4 Bxa4
                               ^(segment removed and placed
			         in header [above])

Comparison: The disadvantage of the ChessU3 tree search, when compared
	  to ChessBase or Chess Assistant, is its size. It's advantage
	  (which exists in no other product) is that it tallies
	  statistics (in the halfmove range) which include the effects
	  of all forward transpositions. The other products do not. This
	  eliminates the surprise of following a favorable line only to
	  have it disappear when a glut of transpositions flow into
	  an advance position.

Suggestion: If you have a line you are interested in--or one that has
	  been saved to LinesU4.txt--place it as the TOP game in the PGN
	  collection you are reading with ChessU3. This will cause the
	  line to appear first in each candidate's menu--so long as the
	  line is followed.

	  Once you have worked out a "repertoire" with PERTO, keep a copy
	  of the "Line Report" handy. Mark all terminators of your
	  chosen line(s) (the longest) with "1-0" or "0-1" terminators (as
	  appropriate). Run ChessU3 at something like "45,1" on the Line
	  Report. This can serve as a reminder of reasonable candidates
	  and also for the times one gets lost in an intricate opening.
	  (To review your repertoire, use reader ChessU4.)

Footnote: In some ways it is rather unfortunate to have to call ChessU3
	  a "tree-searcher." Chess is not a "tree" problem (as it's
	  treated by the databases). Rather, a better analogy would
	  be a river's delta, which has many tributaries, splitting,
	  then flowing back together again.


  -Paul 70641.3236@compuserve.com
