add first draft for tree

cpp/models/abm/test_tree.cpp

@@ -0,0 +1,10 @@
+#include "weighted_decision_tree.h"
+#include <vector>
+
+int main(int argc, char const* argv[])
+{
+    auto nodes         = std::vector<int>({1, 4, 10});
+    auto edges         = std::vector<std::tuple<int, int, double>>({{1, 4, 0.5}, {4, 10, 0.5}});
+    auto decision_tree = weighted_decision_tree(nodes, edges);
+    return 0;
+}

cpp/models/abm/weighted_decision_tree.h

@@ -0,0 +1,54 @@
+/*
+* Copyright (C) 2020-2021 German Aerospace Center (DLR-SC)
+*
+* Authors: Sascha Korf
+*
+* Contact: Martin J. Kuehn <[email protected]>
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*     http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+#include <vector>
+#include <map>
+#include <cmath>
+#include <memory>
+#include <algorithm>
+
+struct TreeNode {
+    int value;
+};
+
+struct TreeEdge {
+    double time_length;
+};
+
+class weighted_decision_tree
+{
+public:
+    weighted_decision_tree(std::vector<int> nodes, std::vector<std::tuple<int, int, double>> edges)
+    {
+        for (auto edge : edges) {
+            auto parent_node = std::find(nodes.begin(), nodes.end(), std::get<0>(edge));
+            auto child_node  = std::find(nodes.begin(), nodes.end(), std::get<1>(edge));
+            build_tree(TreeNode{*parent_node}, TreeEdge{std::get<2>(edge)}, TreeNode{*child_node});
+        }
+    }
+
+private:
+    void build_tree(TreeNode node, TreeEdge edge, TreeNode child)
+    {
+        m_tree.insert({node, std::make_pair(edge, child)});
+    }
+
+    std::map<TreeNode, std::pair<TreeEdge, TreeNode>> m_tree;
+};