GeneXproTools Environment

Choosing the Function Set
 
In the Functions Panel you choose the mathematical/logical and comparison functions you think appropriate to model your data. Here you also choose the probability (or the weight) each function has of being integrated in the chromosomes of the evolving models.

The functions you choose will consist of the function set. And besides the function set, the learning algorithms of GeneXproTools also use a terminal set. But unlike the functions in your function set which can be weighted as many times as you see fit, the terminal set is created automatically by GeneXproTools and consists of the independent variables in your data and, therefore, you cannot weight each terminal differently. But, during adaptation, the chromosomes of the evolving models are created and modified using the elements of both the function and terminal set, reflecting their relative representation. Although you can always handcraft your function set so that it is well-balanced relatively to the number of independent variables in the problem at hand, in GeneXproTools 4.0 this is no longer essential as GeneXproTools balances automatically all function sets. This is particularly important for high-dimensional datasets, say above 100-1000 variables.

GeneXproTools 4.0 offers a total of 279 built-in mathematical functions to choose from, including the mathematical, trigonometric and comparison functions most commonly used by sophisticated programming and modeling software. And for Logic Synthesis there are 258 built-in logical functions available, including all the Boolean functions with one and two inputs, 92 functions with three inputs, and 146 functions with four inputs.

For some problems, a few basic functions operators are more than enough to create extremely accurate and elegant models. But for other problems, more complex functions are necessary to create good models and when inside knowledge of the problem at hand is not producing the expected results, it might be interesting to experiment with different combinations of functions. The Function Selection Tool of GeneXproTools 4.0 helps you to experiment with different function sets very quickly either by pressing the Random button in the Functions Panel or by selecting certain sub-sets of functions.

The functions you select in the Functions Panel are the functions the learning algorithm will explore in order to create a good model for your data. The learning algorithms of GeneXproTools cope very well with virtually any combination of mathematical or logical functions. But sometimes for the sake of simplicity and intelligibility of your models it pays to be frugal and we recommend you give a try to one of the simplest function sets, the one composed of only the basic arithmetic operators. But, of course, the modeling of complex realities sometimes requires more complex functions and GeneXproTools 4.0 provides a wide range of such functions. Furthermore, you can also design user defined functions and add them to the function kit of GeneXproTools and explore new solution spaces with them.

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