Unpickling dictionary that holds pandas dataframes throws AttributeError: 'Dataframe' object has no attribute '_data'

Question

我有一个 class 执行分析并将结果附加为 pandas 数据帧，作为对象属性：

>>> print(test.image.locate_DF)
              y          x       mass  ...    raw_mass        ep  frame
0     60.177142  59.788709  33.433414  ...  242.080256       NaN      0
1     60.651991  59.773904  33.724308  ...  242.355784       NaN      1
2     60.790437  60.190234  31.117164  ...  236.276671       NaN      2
3     60.771933  60.048123  33.558372  ...  240.981395       NaN      3
4     60.251282  59.775139  31.881009  ...  239.239022       NaN      4
...         ...        ...        ...  ...         ...       ...    ...
7212  68.186380  76.477449  18.122817  ...  176.523091       NaN   9410
7213  68.764444  76.574091  17.486454  ...  173.448306       NaN   9415
7214  68.191152  76.473477  17.402975  ...  172.848119  0.868326   9429
7215  67.034103  76.025885  17.010951  ...  170.928067 -0.600854   9431
7216  68.583276  75.309592  17.852992  ...  178.271558       NaN   9432

随后，我将所有重要的对象属性保存在字典中，并 pickle 以备后用：

def save_parameters(self, filepath):
        
        param_dict = {}

    try:
            self.image.locate_DF
        except AttributeError:
            pass
        else:
            param_dict['optical_locate_DF'] = self.image.locate_DF

    with open(filepath, 'wb') as handle:
            pickle.dump(param_dict, handle, 5)

当尝试加载那个 pickled 文件时，我完全没有问题，数据框加载完美：

>>> test.save_parameters('test.pickle')
>>> with open('test.pickle', 'rb') as handle:
...     result = pickle.load(handle)
...
>>> print(result.keys())
dict_keys(['optical_path', 'optical_feature_diameter', 'optical_feature_minmass', 'optical_locate_DF', 'electrical_path', 'electrical_raw_data', 'electrical_processed_data', 'electrical_mean_voltage'])
>>> print(result['optical_locate_DF'])
              y          x       mass  ...    raw_mass        ep  frame
0     60.177142  59.788709  33.433414  ...  242.080256       NaN      0
1     60.651991  59.773904  33.724308  ...  242.355784       NaN      1
2     60.790437  60.190234  31.117164  ...  236.276671       NaN      2
3     60.771933  60.048123  33.558372  ...  240.981395       NaN      3
4     60.251282  59.775139  31.881009  ...  239.239022       NaN      4
...         ...        ...        ...  ...         ...       ...    ...
7212  68.186380  76.477449  18.122817  ...  176.523091       NaN   9410
7213  68.764444  76.574091  17.486454  ...  173.448306       NaN   9415
7214  68.191152  76.473477  17.402975  ...  172.848119  0.868326   9429
7215  67.034103  76.025885  17.010951  ...  170.928067 -0.600854   9431
7216  68.583276  75.309592  17.852992  ...  178.271558       NaN   9432

[7217 rows x 9 columns]

然而，在运行我在 hpc 上分析了一堆这些文件之后，然后尝试打开同一个 pickled 文件（现在它的名称不同了，但它与上面显示的是同一个文件，带有对其进行了相同的分析），我被 pandas 抛出一个属性错误。它指出数据框没有“_data”属性。字典具有相同的键，并且打印不是数据框的键没有任何问题：

>>> resultfile = '../results/diam_15_minmass_17_dist_50_mem_5000_tracklength_500/R9_DNA_50mV_001.pickle'
>>> with open(resultfile, 'rb') as handle:
...     result = pickle.load(handle)
...
>>> print(result.keys())
dict_keys(['optical_path', 'optical_feature_diameter', 'optical_feature_minmass', 'optical_locate_DF', 'optical_tracking_distance', 'optical_tracking_memory', 'optical_tracking_DF', 'optical_kinetics_DF', 'electrical_path', 'electrical_raw_data', 'electrical_processed_data', 'electrical_mean_voltage'])
>>> print(result['optical_locate_DF'])
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/stevenvanuytsel/miniconda3/envs/simultaneous_measurements/lib/python3.8/site-packages/pandas/core/frame.py", line 680, in __repr__
    self.to_string(
  File "/Users/stevenvanuytsel/miniconda3/envs/simultaneous_measurements/lib/python3.8/site-packages/pandas/core/frame.py", line 801, in to_string
    formatter = fmt.DataFrameFormatter(
  File "/Users/stevenvanuytsel/miniconda3/envs/simultaneous_measurements/lib/python3.8/site-packages/pandas/io/formats/format.py", line 593, in __init__
    self.max_rows_displayed = min(max_rows or len(self.frame), len(self.frame))
  File "/Users/stevenvanuytsel/miniconda3/envs/simultaneous_measurements/lib/python3.8/site-packages/pandas/core/frame.py", line 1041, in __len__
    return len(self.index)
  File "/Users/stevenvanuytsel/miniconda3/envs/simultaneous_measurements/lib/python3.8/site-packages/pandas/core/generic.py", line 5270, in __getattr__
    return object.__getattribute__(self, name)
  File "pandas/_libs/properties.pyx", line 63, in pandas._libs.properties.AxisProperty.__get__
  File "/Users/stevenvanuytsel/miniconda3/envs/simultaneous_measurements/lib/python3.8/site-packages/pandas/core/generic.py", line 5270, in __getattr__
    return object.__getattribute__(self, name)
AttributeError: 'DataFrame' object has no attribute '_data'

我查看了 pickle 手册，并通过了一堆 SO 问题，但我似乎无法找出这里出了什么问题。有谁知道如何解决这个问题，以及我是否仍然可以访问该数据？

Answer 1

经过cross-checking模块版本的漫长而痛苦的过程，我发现这个错误是由于pandas版本的更新引起的。我的 mac 仍然是运行 pandas 1.0.5，而 hpc 运行 pandas 1.1.0。显然，两者之间存在不匹配（不确定是在酸洗之后还是用于保存的其他文件格式）。

Answer 2

我遇到了同样的问题。我在 Pandas 1.1.1 的环境中生成了一个 Pandas 数据框，并将其保存到 pickle 文件中。

with open('file.pkl', 'wb') as f:
    pickle.dump(data_frame_object, f)

在另一个会话中解开它并打印数据帧后，我得到了同样的错误。在不同环境中的一些测试显示出以下模式：

Pandas >= 1.1.0 的环境：有效
环境 Pandas == 1.0.5：错误消息如上
Pandas == 1.0.3 的环境：内核崩溃

我在使用 HDF5 格式时遇到了同样的错误，所以这似乎是数据帧和不同 Pandas 版本的兼容性问题。

在受影响的环境中将 Pandas 更新到 1.1.1 解决了我的问题。

Answer 3

也许问题已经解决了。
Emmm，不过还是想补充一下。

我将 pkl 文件保存在服务器上，但是当我将它加载到我的 MAC 上时，它崩溃了，显示 'Dataframe' object has no attribute '_data'

最后，我发现 Mac 上的 pandas 是 1.0.5，但服务器上是 1.1.5。当我把它更新到最新时，它就起作用了。

Unpickling dictionary that holds pandas dataframes throws AttributeError: 'Dataframe' object has no attribute '_data'

Unpickling dictionary that holds pandas dataframes throws AttributeError: 'Dataframe' object has no attribute '_data'

pickle

dataframe

python-3.x

pandas