Modify DataProvider to change backend of the tensors to cpu with the generic set_Backend()

include/aidge/data/DataProvider.hpp

@@ -36,7 +36,6 @@ protected:
     
     size_t mNumberModality;
     std::vector<std::vector<std::size_t>> mDataSizes;
-    std::vector<std::string> mDataBackends;
     std::vector<DataType> mDataTypes;
     
     // Desired size of the produced batches

src/data/DataProvider.cpp

@@ -9,15 +9,13 @@ DataProvider::DataProvider(Database& database, std::size_t batchSize)
     mDatabase(database),
     mBatchSize(batchSize)
 {
-    // Get the tensor dimensions, datatype and backend of each modality to ensure each data have the same
+    // Get the tensor dimensions, datatype and backend of each modality to ensure each data have the samereadBatch
     auto item = mDatabase.getItem(0);
     mNumberModality = item.size();
 
     // Iterating on each data modality in the database
     for (std::size_t i = 0; i < mNumberModality; ++i) {
         mDataSizes.push_back(item[i]->dims());
-        // assert(std::strcmp(item[i]->getImpl()->backend(), "cpu") == 0 && "DataProvider currently only supports cpu backend tensors");
-        // mDataBackends.push_back(item[i]->getImpl()->backend());
         mDataTypes.push_back(item[i]->dataType());
     }
 }
@@ -42,7 +40,6 @@ std::vector<std::shared_ptr<Tensor>> DataProvider::readBatch(std::size_t startIn
         dataBatchSize[i].insert(dataBatchSize[i].begin(), current_batch_size);
         auto batchData = std::make_shared<Tensor>();
         batchData->resize(dataBatchSize[i]);
-        // batchData->setBackend(mDataBackends[i]);
         batchData->setBackend("cpu");
         batchData->setDataType(mDataTypes[i]);
         batchTensors.push_back(batchData);
@@ -61,9 +58,12 @@ std::vector<std::shared_ptr<Tensor>> DataProvider::readBatch(std::size_t startIn
             
             // Assert tensor sizes
             assert(dataSample->dims() == mDataSizes[j] && "DataProvider readBatch : corrupted Data size");
-            
-            // Assert implementation backend
-            // assert(dataSample->getImpl()->backend() == mDataBackends[j] && "DataProvider readBatch : corrupted data backend");
+
+            // Check the backend of the tensor from the database
+            // If not cpu then change the backend to cpu
+            if (strcmp(dataSample->getImpl()->backend(), "cpu") != 0) {
+                dataSample->setBackend("cpu");
+            }
 
             // Assert DataType
             assert(dataSample->dataType() == mDataTypes[j] && "DataProvider readBatch : corrupted data DataType");