public DoubleMatrix RegressionMatrix { get; }

Public ReadOnly Property RegressionMatrix As DoubleMatrix

public:
property DoubleMatrix^ RegressionMatrix {
	DoubleMatrix^ get ();
}

The regression matrix is the predictor matrix (the matrix of values of the independent variables in a regression model), plus a column of leading ones, if the model contains an intercept parameter.
If you modify the data in the regression matrix using this reference, invoke the member function RecalculateParameters() to recalculate the parameters.