public void btnBuildEstimate_Click(IRibbonControl e)
        {
            //check if "Correlation" sheet exists & create if not. Otherwise just grab it.
            EstimateSheet    estimateSheet = ThisAddIn.Model.EstimateSheets[0];
            CorrelationSheet correlSheet   = ThisAddIn.Model.correlationSheet;

            correlSheet.ClearSheet();
            var estimate = new Estimate(estimateSheet, correlSheet, 10);

            correlSheet.CorrelationMatrix = estimate.CorrelMatrix;
            MessageBox.Show($"Transitivity test: {correlSheet.CheckTransitivity()}");
            correlSheet.PrintCorrelationMatrix();
        }
        //private double[] new_eigenvalues { get; set; }

        public CorrelationMatrix(Estimate Parent)
        {
            this.Parent  = Parent;
            Correlations = GetCorrelationMatrix();
            foreach (Correlation correl in Correlations)
            {
                correl.CalculateTransitivity();
            }
            eigenvalues = GetEigenvalues(GetCoefficientsMatrix());
            if (eigenvalues.Min() < 0)
            {
                AdjustToPositiveSemiDefinite();
            }
        }