PoPChess

A major new version of Rybka Aquarium will soon be released. It’s called Rybka Aquarium 2010 and it will be available before the holidays. This new version includes a free update to Rybka 4 when it is released.

One of the biggest changes in Rybka Aquarium 2010 is the greatly improved Interactive Deep Analysis (IDeA). Many players were happy with the possibilities offered by IDeA in Rybka 3 Aquarium, but I’m afraid that it will look like a dinosaur compared to the new version. It provides better automatic analysis and much more effective ways to control the analysis process and the shape of the analysis tree. I’m sure that many serious players will find that the new and improved IDeA is an essential tool to stay competitive.

Analyzing with many engines. The original IDeA could only use one engine for the analysis, but the new version can split the analysis between many engines. You can, for instance, use four instances of single core Rybka for the analysis on a quad computer, essentially reducing the multiprocessor overhead to zero. It’s like getting one extra core for free compared to running Rybka in 4-CPU mode.

Analyzing on a network of computers. This feature is a dream come true for power users, analysts, and serious players who want to take their analysis to a new level. If you own two computers, you can of course run Aquarium on one of them and use it for the analysis. In the new version you can also add engines running on your other computer to the pool of IDeA analysis engines. Using this method I have tested up to thirty-five engines analyzing simultaneously. The engines were running on various computers, some on my local network while others were located in different countries and connected to my Aquarium over the Internet. IDeA takes care of splitting the analysis between the available engines.

Multiple IDeA projects analyzed in parallel. You can define many analysis projects, each with its own analysis and tree settings. IDeA can analyze any number of those projects in parallel. The status of each project is saved between sessions, so you can manage many different IDeA projects much easier than before.

Multiple analysis “roots” for a single project. The starting position for IDeA analysis is called a “root.” If you are analyzing a position in IDeA when another interesting position shows up in the tree, you can make it a new root, without even stopping the analysis. You can remove the original root or let IDeA analyze from both roots. You can use this feature to focus IDeA on selected positions without restarting it. IDeA can keep a list of all roots that have been used in a project.

Shaping the analysis tree. The former single “variativity” parameter was not very effective and didn’t affect IDeA sufficiently. Now there are a number of new settings that have a significant influence on the shape of the IDeA analysis tree.

• The “Tree width” parameter determines how wide the resulting IDeA tree will be. Although similar to “variativity,” this new parameter is much more effective.
• The maximum length of variations can be defined. This allows you to make the tree denser near the root and avoid very long variations.
• Analysis can be limited to positions within a certain evaluation range. Positions outside the specified range will not be explored further.
• The number of alternatives generated for White/Black can be limited.
• A “preferred side” can be set; e.g., for developing your opening repertoire.
• A list of “thematic moves” can be given. You can use them to ensure that certain moves are always analyzed. For instance, in an attacking game you might want to make sure that the moves Bxh7+ and Ng5 are considered.
• “False alarm check” immediately performs additional analysis of new moves that look “too good to be true,” preventing IDeA from spending more time on them if they turn out to be worse than they first looked.

All of these settings can be changed on the fly during the IDeA session, further emphasizing that IDeA is designed to be used as an interactive tool.

Move repetition detection. IDeA tasks no longer consist of a single position, but a full line that leads from the root node to the position to be analyzed. This enables Rybka to report 0.00 scores for twofold repetitions, and is generally more correct. This also leads to the fifty-move rule being observed.

Automatic backup of analysis trees. Besides more robust tree handling in IDeA, the analysis trees are now automatically backed up. Not only does it prevent data loss, but it may also prove useful in some other cases too.

Browsing the analysis queue. You can see a list of all tasks for the current stage; which tasks were automatically scheduled by IDeA and which ones you added manually. The corresponding positions can be displayed on the board and you can see the engine’s output for the selected task, prioritize the tasks, and delete unnecessary ones. If there are tasks waiting in the queue when you stop the analysis, they will be stored and processed the next time you start the analysis, even if you restart Aquarium.