Esempio n. 1
0
        static void Main(string[] args)
        {
            Attribute soft_skills     = new Attribute("soft_skills", new string[] { "Poor", "Avg", "Good" });
            Attribute time_management = new Attribute("time_management", new string[] { "Developed", "Enhanced", "Strengthened" });
            Attribute problem_solving = new Attribute("problem_solving", new string[] { "Developed", "low" });
            Attribute decision_making = new Attribute("decision_making", new string[] { "yes", "no" });

            Attribute[] attributes = new Attribute[] { soft_skills, time_management, problem_solving, decision_making };

            DataTable samples = getDataTable();

            j48classify j48  = new j48classify();
            TreeNode    root = j48.mountTree(samples, "result", attributes);

            printNode(root, "");
        }
Esempio n. 2
0
        private TreeNode internalMountTree(DataTable samples, string targetAttribute, Attribute[] attributes)
        {
            if (allSamplesPositives(samples, targetAttribute) == "c1")
            {
                return(new TreeNode(new Attribute("c1")));
            }

            if (allSamplesNegatives(samples, targetAttribute) == "c1")
            {
                return(new TreeNode(new Attribute("c2")));
            }

            if (attributes.Length == 0)
            {
                return(new TreeNode(new Attribute(getMostCommonValue(samples, targetAttribute))));
            }

            mTotal           = samples.Rows.Count;
            mTargetAttribute = targetAttribute;
            mTotalPositives  = countTotalPositives(samples);

            mEntropySet = calcEntropy(mTotalPositives, mTotal - mTotalPositives);

            Attribute bestAttribute = getBestAttribute(samples, attributes);

            TreeNode root = new TreeNode(bestAttribute);

            DataTable aSample = samples.Clone();

            foreach (string value in bestAttribute.values)
            {
                aSample.Rows.Clear();

                DataRow[] rows = samples.Select(bestAttribute.AttributeName + " = " + "'" + value + "'");

                foreach (DataRow row in rows)
                {
                    aSample.Rows.Add(row.ItemArray);
                }
                ArrayList aAttributes = new ArrayList(attributes.Length - 1);
                for (int i = 0; i < attributes.Length; i++)
                {
                    if (attributes[i].AttributeName != bestAttribute.AttributeName)
                    {
                        aAttributes.Add(attributes[i]);
                    }
                }


                if (aSample.Rows.Count == 0)
                {
                    return(new TreeNode(new Attribute(getMostCommonValue(aSample, targetAttribute))));
                }
                else
                {
                    j48classify dc3       = new j48classify();
                    TreeNode    ChildNode = dc3.mountTree(aSample, targetAttribute, (Attribute[])aAttributes.ToArray(typeof(Attribute)));
                    root.AddTreeNode(ChildNode, value);
                }
            }

            return(root);
        }