Question

I am trying to build a data structure that can store the trial by trail results of a group of different tests I am running. The test all consist of a number of trails but some of the information that I want to save and later use is different for the different tests. For example, the results of TestA might look like:

Trial(int)   WasResponseCorrect(bool)   WhichButtonWasPressed(string)   SimulusLevel(double)

   1                  false                         "Up"                         3.5
   2                  true                          "Left"                       6.5

Where TestB might have different types of result fields:

Trial(int)    WasResponseCorrect(bool)    ColorPresented(string)    LetterPresented(char)     LetterGuessed(Char)
  1                     false                      green                     G                        C

  2                     false                      blue                      H                        F

I was thinking of creating a dictionary with the field names as the keys (ex. WasResponseCorrect) and an array of the field values as the values of dic. I can’t figure out how to do that. Maybe there is a better way to store the information but I can’t think of how to do it. I am working with .net (VB and C#) but I think I can understand and convert most any code if you know of examples in other languages. Thanks!

Answer 1

Without knowing more about your requirements (how you are going to store the data, for example), it seems like polymorphism is what you’re looking for. That is, you have a superclass (called Trial) and subclasses that represent the specific trial types. For example:

public class Trial {
    public int Id { get; set; }
    public bool WasResponseCorrect { get; set; } // if this is in every type of trial
    // anything else that is common to ALL trial types
}

public class TrialA : Trial {
    public string WhichButtonWasPressed { get; set; }
    public double SimulusLevel { get; set; }
}

public class TrialB : Trial {
    public string ColorPresented { get; set; }
    public char LetterPresented { get; set; }
    public char LetterGuessed { get; set; }
}

That way you can have a list of Trial objects, but the actual runtime type of those objects can be TrialA or TrialB.