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GCG

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Detection Parameters

A list of all detection parameters can be seen (and searched) when inserting set detection into the search box on the page of The Interactive Menu.
If you want a more detailed description of the detection parameter adjustment, please check the use case Paint my Problem.

Modifying Parameters of the GCG Detection

GCG performs its detection using Classifiers and Detectors that classify different variable and constraint types, respectively detect structures each.

There are multiple reasons to deactivate and activate classifiers and detectors. Most often, you want to...

  • Activate classifiers/detectors that are deactivated by default (and deactivate the respective other ones) Activating and deactivating classifiers and detectors can be particularly helpful not only to find specific structures but also to test the behavior of your own detector with all others deactivated.
  • Change priorities classifiers/detectors to find a specific structure in your program (see How to add a detector and How to add a classifier for more information)

Activate and Deactivate Classifiers and Detectors

Sometimes you might be tempted to deactivate all detectors except for one. Note that you can always choose a decomposition using The Explore Menu, but then there might be decompositions where different detectors (e.g. also ones you don't want to use) were used. Thus, before detecting and solving your problem, you will have to type set detection detectors to completely deactivate detectors. Once you are in that submenu, you can select detectors, e.g. consclass and disable them with enabled FALSE. You will see the following feedback:

GCG/set/detection/detectors/consclass> enabled FALSE
detection/detectors/consclass/enabled = FALSE

You can also selectively deactivate one of the two more functionalities except for propagating (finishing/postprocessing, see here), then you will have to use {finishing,postprocessing}enabled FALSE.
If you want to directly deactivate all detectors (e.g. to activate one single one again), you can also do that using the off function of the emphasis setting (see "Emphasis Settings").

Change Priorities of Classifiers and Detectors

We use the same commands as above to enter the settings for a detector, again e.g. consclass. Then, instead of disabling or enabling them, we can also tell GCG to change the priority of that detector, e.g. with priority 42. You will be able to observe the following:

GCG/set/detection/detectors/consclass> priority
current value: 0, new value [-2147483648,2147483647]: 42
detection/detectors/consclass/priority = 42

This detector will now be called before others (see The GCG Detection).

Emphasis Settings

Another method to change parameters of the detection is by using our predefined emphasis settings. There are three different settings that we deliver and an off setting that will deactivate all functionalities of all detectors.

aggressive sets detection <aggressive>
default sets detection <default>
fast sets detection <fast>
off turns <off> all detectors

The different emphasis settings will modify parameters from the activation of specified detectors to the number of rounds they are called (see The GCG Detection).

Change Parameters of the Detection

You can also modify other parameters of the detection. You can set them by entering set and then detection. In the following, we give a list of all parameters that can then be changed.
A list of all detection parameters can be seen (and searched) when inserting set detection into the search box on the page of The Interactive Menu.