refactor/tensor: convert to the new memory API

Fix SharedTensor::new() usage.

REFERENCE: autumnai/collenchyma#37, autumnai/collenchyma#62

src/main.rs

@@ -156,7 +156,6 @@ fn run_mnist(model_name: Option<String>, batch_size: Option<usize>, learning_rat
 
     // set up backends
     let backend = ::std::rc::Rc::new(Backend::<Cuda>::default().unwrap());
-    let native_backend = ::std::rc::Rc::new(Backend::<Native>::default().unwrap());
 
     // set up solver
     let mut solver_cfg = SolverConfig { minibatch_size: batch_size, base_lr: learning_rate, momentum: momentum, .. SolverConfig::default() };
@@ -168,9 +167,8 @@ fn run_mnist(model_name: Option<String>, batch_size: Option<usize>, learning_rat
     let mut confusion = ::leaf::solver::ConfusionMatrix::new(10);
     confusion.set_capacity(Some(1000));
 
-    let mut inp = SharedTensor::<f32>::new(backend.device(), &vec![batch_size, 1, 28, 28]).unwrap();
-    let label = SharedTensor::<f32>::new(native_backend.device(), &vec![batch_size, 1]).unwrap();
-    inp.add_device(native_backend.device()).unwrap();
+    let inp = SharedTensor::<f32>::new(&[batch_size, 1, 28, 28]);
+    let label = SharedTensor::<f32>::new(&[batch_size, 1]);
 
     let inp_lock = Arc::new(RwLock::new(inp));
     let label_lock = Arc::new(RwLock::new(label));