Upd SequentialScheduler::backward() member function

include/aidge/scheduler/Scheduler.hpp

@@ -69,7 +69,7 @@ public:
 
     /**
      * @brief Place the data tensors inside in the data input tensor of the graphView. In case of multiple data input tensors, they are mapped to producers in the order given by the graph.
-     * 
+     *
      * @param data data input tensors
      */
     void connectInputs(std::vector<std::shared_ptr<Aidge::Tensor>> data);
@@ -82,7 +82,7 @@ public:
     /**
      * @brief Run the provided Computational Graph with a batch of data
      */
-    void backward(bool forwardDims = true, bool verbose = false);
+    void backward(std::vector<std::shared_ptr<Aidge::Tensor>> data, bool instantiateGrad = true, bool verbose = false);
 
     /**
      * @brief Save in a Markdown file the order of layers execution.

src/scheduler/Scheduler.cpp

@@ -476,10 +476,21 @@ void Aidge::SequentialScheduler::forward(bool forwardDims, bool verbose, std::ve
     }
 }
 
-void Aidge::SequentialScheduler::backward(bool instanciateGrad, bool verbose) {
-    // Forward dims (if allowed)
-    if (instanciateGrad) {compile_gradient(mGraphView); }
-
+void Aidge::SequentialScheduler::backward(std::vector<std::shared_ptr<Aidge::Tensor>> data, bool instanciateGrad, bool verbose) {
+    // create ad set Grad values
+    if (instanciateGrad) { compile_gradient(mGraphView); }
+
+    const auto& ordered_outputs = mGraphView->getOrderedOutputs();
+    AIDGE_ASSERT(ordered_outputs.size() == data.size(), "You must provide the \
+                   right number of data objects to run the backward function. \
+                   {} outputs detected for the current GraphView when {} were \
+                   provided.", ordered_outputs.size(), data.size());
+    for (std::size_t i = 0; i < ordered_outputs.size(); ++i) {
+        const std::shared_ptr<OperatorTensor> op_ = std::dynamic_pointer_cast<OperatorTensor>(ordered_outputs[i].first->getOperator());
+        const std::shared_ptr<Tensor> t_grad = op_->getOutput(ordered_outputs[i].second)->grad();
+        AIDGE_ASSERT(data[i]->dims() == t_grad->dims(), "Wrong gradient size.");
+        *t_grad = data[i]->clone();
+    }
     // Generate scheduling *only if empty*
     // If scheduling was already generated (in one or several steps, i.e. one or
     // several successive call to generateScheduling()), do not generate it twice
@@ -487,18 +498,21 @@ void Aidge::SequentialScheduler::backward(bool instanciateGrad, bool verbose) {
         this->generateScheduling();
     }
 
+    // map of node <-> info to display with verbose
+    const auto namePtrTable = mGraphView->getRankedNodesName("{0} ({1}#{3})");
+
     // Clear previous scheduling results
     mScheduling.clear();
 
-    int cpt = 0;
-    for (auto runnable = mStaticSchedule.crbegin(); runnable != mStaticSchedule.crend(); ++runnable) {
+    std::size_t cpt = 0;
+    // run scheduled operators in reverse order
+    const auto& runnableList = mStaticSchedule.at(mStaticScheduleStep);
+    for (auto runnable = runnableList.crbegin(); runnable != runnableList.crend(); ++runnable) {
         if (verbose)
-            printf("run: %s\n",
-                    ((*runnable)->type() + "_" + std::to_string(reinterpret_cast<uintptr_t>(runnable->get()))).c_str());
+            fmt::print("run: {}\n", namePtrTable.at(*runnable));
         else
             drawProgressBar(static_cast<float>(cpt) / static_cast<float>(mStaticSchedule.size()), 50,
-                            (std::string("running ") + (*runnable)->type() + "_" +
-                                std::to_string(reinterpret_cast<uintptr_t>(runnable->get()))));
+                            (std::string("running ") + namePtrTable.at(*runnable)));
         const auto tStart = std::chrono::high_resolution_clock::now();
         (*runnable)->backward();
         const auto tEnd = std::chrono::high_resolution_clock::now();
@@ -506,7 +520,12 @@ void Aidge::SequentialScheduler::backward(bool instanciateGrad, bool verbose) {
         cpt++;
     }
     if (!verbose) drawProgressBar(1.0, 50, "                                   ");
-    printf("\n");
+    fmt::print("\n");
+
+    ++mStaticScheduleStep;
+    if (mStaticScheduleStep == mStaticSchedule.size()) {
+        mStaticScheduleStep = 0;
+    }
 }