fix train lenet script

mindspore/lite/examples/train_lenet/model/lenet_export.py

@@ -23,7 +23,7 @@ from train_utils import TrainWrap
 
 n = LeNet5()
 n.set_train()
-context.set_context(mode=context.PYNATIVE_MODE, device_target="GPU", save_graphs=False)
+context.set_context(mode=context.PYNATIVE_MODE, device_target="CPU", save_graphs=False)
 
 BATCH_SIZE = 32
 x = Tensor(np.ones((BATCH_SIZE, 1, 32, 32)), mstype.float32)

mindspore/lite/examples/train_lenet/prepare_and_run.sh

@@ -52,7 +52,7 @@ if [ "$TARBALL" == "" ]; then
   else
     file=$(ls ../../../../output/mindspore-lite-*-train-linux-x64.tar.gz)
   fi
-  if [ -f ${file} ]; then
+  if [[ ${file} != "" ]] && [[ -f ${file} ]]; then
     TARBALL=${file}
   else
     echo "release.tar.gz was not found"

mindspore/lite/examples/transfer_learning/prepare_and_run.sh

@@ -51,7 +51,7 @@ if [ "$TARBALL" == "" ]; then
   else
     file=$(ls ../../../../output/mindspore-lite-*-train-linux-x64.tar.gz)
   fi
-  if [ -f ${file} ]; then
+  if [[ ${file} != "" ]] && [[ -f ${file} ]]; then
     TARBALL=${file}
   else
     echo "release.tar.gz was not found"