Match Control

Into control of your matches | engine versions.


LOS.EXE is a simple command line tool (operation by single character keys) that will read the PGN of your matches and stores the overall information in a text-based database called los.txt whereafter your browser will start and show you the results.

When using 6 Fruit and 2 Stockfish matches we get [ link ]

Changing to database mix.txt we get [ link ]

We can sort databases on match score | number of games | LOS | Time control | date | match | and parameter usuage or match description.



Double click Match Control or type LOS from the command line.

You are offered 7 choices - (H)tml | (P)gn | (S)ort | (D)atabase | (E)quilibrium | (G)ame Split | (M)atch

•  Press "H" (or "h") will produce the HTML;

•  "P" will prompt you for the PGN to be added;

•  "D" allows you to change (or create a new) database;

•  "S" moves you to the sort menu;

•  "G" splits the PGN in parts defined by "G" making the match development visible, see last chapter;

•  "E" Test an engine when it reaches Equilibrium in self-play,see last chapter;

•  "M" Match Overview;

•  "Q" will exit the program.

Note - All input is lower | upper case independent.

Note - When prompted for the PGN then the extension ".pgn" is not required. Simply type "all" instead of "all.pgn".

The sort menu offers you 7 sorting possibilities, see links above for results.

Sort on ?

(S)core | (G)ames | (L)os | (T)ime | (D)ate (M)atch | (P)aram | (E)xit


Format of a database

The most easy way the maintain the database is after adding a match to open the database (for instance LOS.TXT) with a text editor and modify the first [Match] and second [Parameter] items to your wishes.


SF5 [mob=125] - SF5,[Mobility (Midgame) = 125],4000,51.1%,98.0%,40/10,2018.06.23,sf5-mob-125.pgn,17.96,17.85

Just stick to the comma driven format.


On Depths

In case you want to include the depths of engines (see the blue above) consider Protools. Copy the PGN into the PGN folder of Protools, start the program, press "F1", choose "Match Stats" and select your PGN, your browser will show you the overall depths of the 2 engines. Example.

As an alternative consider GAD, works for Winboard and Cutechess PGN's.


New in version 1.2

silent update

Testing a program when it reaches Equilibrium in self-play at a given time control. We play an eng-eng match between 2 identical engines to investigate how many games it needs to settle for a (say) score in the range of 49.8% - 50.2%, the constant equilibrium state, the green in the pictures below.

Click picture to enlatge

Stockfish 9 soon is in the green area and rock solid thereafter.

Click picture to enlarge

ProDeo needs more games to reach  Equilibrium.

It might be useful to repeat this process 2-3-4-5 times as a hint how many games to play when testing candidate improvements. Another usefulness of the Equilibrium tool is to review matches for possible recalcitrant randomness that may have influenced the match result.


Press "G" and type the number of games for each step, default setting is 1000 games, in the above examples 500 is used. Press "P" type the PGN file and when finished "E".


1. The [Event] tag in the first PGN game is used to describe the version in test.

2. SF9.PGN is included in the download to enable to reproduce the above result.

3. Used colors red | red-orange | orange | orange-yellow | yellow | yellow-green | green.

Source code included for further development.