Accord.net NaiveBayesLearning "Index was outside the bounds of the array"

Question

I am using Accord.net 3.7.0 in dot net core 1.1.

The algorithm I use is naive bayesian. And the source code of the learning mechanism is as follows:

    public LearningResultViewModel NaiveBayes(int[][] inputs, int[] outputs)
    {
        // Create a new Naive Bayes learning
        var learner = new NaiveBayesLearning();

        // Learn a Naive Bayes model from the examples
        NaiveBayes nb = learner.Learn(inputs, outputs);

        #region test phase
        // Compute the machine outputs
        int[] predicted = nb.Decide(inputs);

        // Use confusion matrix to compute some statistics.
        ConfusionMatrix confusionMatrix = new ConfusionMatrix(predicted, outputs, 1, 0);
        #endregion

        LearningResultViewModel result = new LearningResultViewModel()
        {
            Distributions = nb.Distributions,
            NumberOfClasses = nb.NumberOfClasses,
            NumberOfInputs = nb.NumberOfInputs,
            NumberOfOutputs = nb.NumberOfOutputs,
            NumberOfSymbols = nb.NumberOfSymbols,
            Priors = nb.Priors,
            confusionMatrix = confusionMatrix
        };

        return result;
    }

I have tested this piece of code on a little data but as data grew the

Index was outside the bounds of the array

error occurred.

As I can't navigate in the Learn method so I don't know what to do. the screen shot of the run-time is this:

No extra information, no inner exception no IDEA!!!

TG.

// UPDATE_1 ***

The inputs array is a 180 by 4 matrix (array) as the bellow image shows:

which has 4 columns in every row. checked by hand (I can share its video too if needed!!!)

The outputs array is a 180 one as shown here:

which only contains 0 and 1 (I can share its video too if needed!!!).

And about NaiveBayesinLearning doc is here:

NaiveBayesinLearning

More examples bottom of this page:

More examples

And the learn method docs here:

learn method doc

Answer 1

According to the comments and the Ideas from them I have suspected to the values of matrix. So I have investigated it:

As shown in image above, some rows have below zero values. The inputs matrix is generated by Codification which is used in the examples of here:

NaiveBayes

with the docs below:

Codification docs

the codification -1 was with the values of null. Like the screen shot below:

So my solution was replacing null values with "null". But may be there is better solutions.

Now the caller method that contains fixed data is as follows:

    public LearningResultViewModel Learn(EMVDBContext dBContext, string userId, LearningAlgorithm learningAlgorithm)
    {
        var learningDataRaw = dBContext.Mutants
            .Include(mu => mu.MutationOperator)
            .Where(mu => mu.Equivalecy == 0 || mu.Equivalecy == 10);

        string[] featureTitles = new string[] {
        "ChangeType",
        "OperatorName",
        "OperatorBefore",
        "OperatorAfter",
        };

        string[][] learningInputNotCodified = learningDataRaw.Select(ldr => new string[] {
            ldr.ChangeType.ToString(),
            ldr.MutationOperator.Name??"null",
            ldr.MutationOperator.Before??"null",
            ldr.MutationOperator.After??"null",
        }).ToArray();

        int[] learningOutputNotCodified = learningDataRaw.Select(ldr => ldr.Equivalecy == 0 ? 0 : 1).ToArray();

        #region Codification phase
        // Create a new codification codebook to
        // convert strings into discrete symbols
        Codification codebook = new Codification(featureTitles, learningInputNotCodified);

        // Extract input and output pairs to train
        int[][] learningInput = codebook.Transform(learningInputNotCodified);

        switch (learningAlgorithm)
        {
            case LearningAlgorithm.NaiveBayesian:
                return learningService.NaiveBayes(learningInput, learningOutputNotCodified);
                break;
            case LearningAlgorithm.SVM:
                break;
            default:
                break;
        }
        #endregion

        return null;
    }

I wish this will help the others encountering same problem.