fix bug where acc is always 0 during SLANet training (#2482)

paddlex/repo_apis/PaddleOCR_api/configs/SLANet.yaml

@@ -97,7 +97,7 @@ Train:
           size: [488, 488]
       - ToCHWImage:
       - KeepKeys:
-          keep_keys: [ 'image', 'structure', 'bboxes', 'bbox_masks', 'shape' ]
+          keep_keys: [ 'image', 'structure', 'bboxes', 'bbox_masks', 'length', 'shape' ]
   loader:
     shuffle: True
     batch_size_per_card: 48
@@ -133,7 +133,7 @@ Eval:
           size: [488, 488]
       - ToCHWImage:
       - KeepKeys:
-          keep_keys: [ 'image', 'structure', 'bboxes', 'bbox_masks', 'shape' ]
+          keep_keys: [ 'image', 'structure', 'bboxes', 'bbox_masks', 'length', 'shape' ]
   loader:
     shuffle: False
     drop_last: False

paddlex/repo_apis/PaddleOCR_api/configs/SLANet_plus.yaml

@@ -97,7 +97,7 @@ Train:
           size: [488, 488]
       - ToCHWImage:
       - KeepKeys:
-          keep_keys: [ 'image', 'structure', 'bboxes', 'bbox_masks', 'shape' ]
+          keep_keys: [ 'image', 'structure', 'bboxes', 'bbox_masks', 'length', 'shape' ]
   loader:
     shuffle: True
     batch_size_per_card: 48
@@ -133,7 +133,7 @@ Eval:
           size: [488, 488]
       - ToCHWImage:
       - KeepKeys:
-          keep_keys: [ 'image', 'structure', 'bboxes', 'bbox_masks', 'shape' ]
+          keep_keys: [ 'image', 'structure', 'bboxes', 'bbox_masks', 'length', 'shape' ]
   loader:
     shuffle: False
     drop_last: False