depth to trees

CMakeLists.txt

@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.25)
-project(blt-gp VERSION 0.0.54)
+project(blt-gp VERSION 0.0.55)
 
 include(CTest)
 

examples/gp_test_7.cpp

@@ -56,11 +56,11 @@ void print_best()
     auto best = program.get_best<10>();
     
     for (auto& v : best)
-        BLT_TRACE(v.get().get_evaluation_value<float>(nullptr));
-    std::string small("--------------------------");
-    for (blt::size_t i = 0; i < std::to_string(program.get_current_generation()).size(); i++)
-        small += "-";
-    BLT_TRACE(small);
+        BLT_TRACE("%lf (depth: %ld)", v.get().get_evaluation_value<float>(nullptr), v.get().get_depth(program));
+    //std::string small("--------------------------");
+    //for (blt::size_t i = 0; i < std::to_string(program.get_current_generation()).size(); i++)
+    //    small += "-";
+    //BLT_TRACE(small);
 }
 
 /**

include/blt/gp/program.h

@@ -36,7 +36,6 @@
 #include <blt/std/types.h>
 #include <blt/std/utility.h>
 #include <blt/std/memory.h>
-#include <blt/std/meta.h>
 #include <blt/gp/fwdecl.h>
 #include <blt/gp/typesystem.h>
 #include <blt/gp/operations.h>
@@ -280,8 +279,8 @@ namespace blt::gp
             template<typename Container, typename Callable>
             void evaluate_fitness(Callable&& fitness_function, Container& result_storage)
             {
-                for (const auto& ind : blt::enumerate(current_pop.get_individuals()))
-                    ind.second.raw_fitness = static_cast<double>(fitness_function(ind.second.tree, result_storage, ind.first));
+               for (const auto& ind : blt::enumerate(current_pop.get_individuals()))
+                   ind.second.raw_fitness = static_cast<double>(fitness_function(ind.second.tree, result_storage, ind.first));
                 double min = 0;
                 for (auto& ind : current_pop.get_individuals())
                 {

include/blt/gp/tree.h

@@ -74,6 +74,8 @@ namespace blt::gp
             
             evaluation_context evaluate(void* context);
             
+            blt::size_t get_depth(gp_program& program);
+            
             /**
              * Helper template for returning the result of the last evaluation
              */
@@ -118,7 +120,7 @@ namespace blt::gp
         
         individual() = default;
         
-        explicit individual(tree_t&& tree): tree(tree)
+        explicit individual(tree_t&& tree): tree(std::move(tree))
         {}
         
         explicit individual(const tree_t& tree): tree(tree)

src/tree.cpp

@@ -149,4 +149,44 @@ namespace blt::gp
         
         out << '\n';
     }
+    
+    blt::size_t tree_t::get_depth(gp_program& program)
+    {
+        blt::size_t depth = 0;
+        
+        auto operations_stack = operations;
+        std::vector<blt::size_t> values_process;
+        std::vector<blt::size_t> value_stack;
+        
+        for (const auto& op : operations_stack)
+        {
+            if (op.is_value)
+                value_stack.push_back(1);
+        }
+        
+        while (!operations_stack.empty())
+        {
+            auto operation = operations_stack.back();
+            // keep the last value in the stack on the process stack stored in the eval context, this way it can be accessed easily.
+            operations_stack.pop_back();
+            if (operation.is_value)
+            {
+                auto d = value_stack.back();
+                depth = std::max(depth, d);
+                values_process.push_back(d);
+                value_stack.pop_back();
+                continue;
+            }
+            blt::size_t local_depth = 0;
+            for (blt::size_t i = 0; i < program.get_operator_info(operation.id).argc.argc; i++)
+            {
+                local_depth = std::max(local_depth, values_process.back());
+                values_process.pop_back();
+            }
+            value_stack.push_back(local_depth + 1);
+            operations_stack.emplace_back(empty_callable, operation.transfer, operation.id, true);
+        }
+        
+        return depth;
+    }
 }