在Google Colab运行YOLOv5遇yaml.scanner.ScannerError问题求助

问题 #

在Google Colab中运行YOLOv5训练命令时触发YAML解析错误，报错指向data.yaml文件第6行第6列。

执行的训练命令：

!python /content/yolov5/train.py --batch 70 --epochs 30 --data "/content/elec_meter_yaml/data.yaml" --cfg /content/yolov5/models/yolov5x.yaml  --weights yolov5x.pt --name runs

错误信息：

Traceback (most recent call last):
  File "/content/yolov5/train.py", line 640, in <module>
    main(opt)
  File "/content/yolov5/train.py", line 529, in main
    train(opt.hyp, opt, device, callbacks)
  File "/content/yolov5/train.py", line 112, in train
    data_dict = data_dict or check_dataset(data)  # check if None
  File "/content/yolov5/utils/general.py", line 518, in check_dataset
    data = yaml_load(data)  # dictionary
  File "/content/yolov5/utils/general.py", line 603, in yaml_load
    return yaml.safe_load(f)
  File "/usr/local/lib/python3.8/dist-packages/yaml/__init__.py", line 125, in safe_load
    return load(stream, SafeLoader)
  File "/usr/local/lib/python3.8/dist-packages/yaml/__init__.py", line 81, in load
    return loader.get_single_data()
  File "/usr/local/lib/python3.8/dist-packages/yaml/constructor.py", line 49, in get_single_data
    node = self.get_single_node()
  File "/usr/local/lib/python3.8/dist-packages/yaml/composer.py", line 36, in get_single_node
    document = self.compose_document()
  File "/usr/local/lib/python3.8/dist-packages/yaml/composer.py", line 58, in compose_document
    self.get_event()
  File "/usr/local/lib/python3.8/dist-packages/yaml/parser.py", line 118, in get_event
    self.current_event = self.state()
  File "/usr/local/lib/python3.8/dist-packages/yaml/parser.py", line 193, in parse_document_end
    token = self.peek_token()
  File "/usr/local/lib/python3.8/dist-packages/yaml/scanner.py", line 129, in peek_token
    self.fetch_more_tokens()
  File "/usr/local/lib/python3.8/dist-packages/yaml/scanner.py", line 223, in fetch_more_tokens
    return self.fetch_value()
  File "/usr/local/lib/python3.8/dist-packages/yaml/scanner.py", line 577, in fetch_value
    raise ScannerError(None, None,
yaml.scanner.ScannerError: mapping values are not allowed here
  in "/content/elec_meter_yaml/data.yaml", line 6, column 6

原data.yaml文件内容：

train = '/content/elec_meter_yaml/train.txt'
val = '/content/elec_meter_yaml/val.txt'
test = '/content/elec_meter_yaml/test.txt'
nc = 12

names:
  0: one
  1: two
  2: three
  3: four
  4: five
  5: six
  6: seven
  7: eight
  8: nine
  9: zero
  10: meter
  11: dot

解决方案 #

错误根源 #

YAML语法规定键值对必须用键: 值（冒号后必须加空格）的格式分隔，原文件前四行使用的=符号不符合YAML规范，导致解析器无法正确识别文件结构，进而触发后续语法错误。

修正后的data.yaml内容 #

train: '/content/elec_meter_yaml/train.txt'
val: '/content/elec_meter_yaml/val.txt'
test: '/content/elec_meter_yaml/test.txt'
nc: 12

names:
  0: one
  1: two
  2: three
  3: four
  4: five
  5: six
  6: seven
  7: eight
  8: nine
  9: zero
  10: meter
  11: dot

额外注意事项 #

• YAML对缩进敏感，names下的每个类别条目必须保持相同缩进（推荐用2个空格）
• 若路径中无特殊字符（如空格），可省略单引号，例如：train: /content/elec_meter_yaml/train.txt

内容的提问来源于stack exchange，提问作者박경덕