Introduce training mode switch to Dropout layer

Author: aobolensk

include/layers/DropOutLayer.hpp

@@ -8,10 +8,12 @@ namespace it_lab_ai {
 class DropOutLayer : public Layer {
  private:
   double drop_rate_;
+  bool training_mode_;
 
  public:
-  DropOutLayer(double drop_rate = 0.0) : Layer(kDropout) {
+  DropOutLayer(double drop_rate = 0.0, bool training_mode = false) : Layer(kDropout) {
     drop_rate_ = drop_rate;
+    training_mode_ = training_mode;
   }
   void run(const std::vector<Tensor>& input,
            std::vector<Tensor>& output) override;

src/layers/DropOutLayer.cpp

@@ -11,6 +11,12 @@ void DropOutLayer::run(const std::vector<Tensor>& input,
   if (input.size() != 1) {
     throw std::runtime_error("DropOutLayer: Input tensors not 1");
   }
+  
+  // If not in training mode, just pass through the input
+  if (!training_mode_) {
+    output[0] = input[0];
+    return;
+  }
   const double lower_bound = 0;
   const double upper_bound = 100;
   std::uniform_real_distribution<double> unif(lower_bound, upper_bound);