Question

我尝试使用以下代码对数据进行随机播放。

import pandas as pd
import numpy as np

from sklearn.naive_bayes import MultinomialNB
 data = pd.read_csv('dataset.txt')
 np.random.shuffle(data)

然而，运行它会给我以下错误。我不明白这个错误来自哪里。

Traceback (most recent call last):
File "sample2.py", line 12, in <module>
 np.random.shuffle(data)
File "mtrand.pyx", line 4668, in mtrand.RandomState.shuffle (numpy/random /mtrand/mtrand.c:30498)
 File "mtrand.pyx", line 4671, in mtrand.RandomState.shuffle (numpy/random/mtrand/mtrand.c:30438)
 File "/Users/marcvanderpeet/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/pandas/core/frame.py", line 1992, in __getitem__
 return self._getitem_column(key)
 File "/Users/marcvanderpeet/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/pandas/core/frame.py", line 2004, in _getitem_column
 result = result[key]
 File "/Users/marcvanderpeet/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/pandas/core/frame.py", line 1992, in __getitem__
 return self._getitem_column(key)
 File "/Users/marcvanderpeet/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/pandas/core/frame.py", line 1999, in _getitem_column
 return self._get_item_cache(key)
 File "/Users/marcvanderpeet/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/pandas/core/generic.py", line 1345, in _get_item_cache
 values = self._data.get(item)
 File "/Users/marcvanderpeet/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/pandas/core/internals.py", line 3225, in get
 loc = self.items.get_loc(item)
 File "/Users/marcvanderpeet/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/pandas/indexes/base.py", line 1878, in get_loc
 return self._engine.get_loc(self._maybe_cast_indexer(key))
 File "pandas/index.pyx", line 137, in pandas.index.IndexEngine.get_loc  (pandas/index.c:4027)
  File "pandas/index.pyx", line 157, in pandas.index.IndexEngine.get_loc (pandas/index.c:3891)
  File "pandas/hashtable.pyx", line 675, in pandas.hashtable.PyObjectHashTable.get_item (pandas/hashtable.c:12408)
  File "pandas/hashtable.pyx", line 683, in pandas.hashtable.PyObjectHashTable.get_item (pandas/hashtable.c:12359)

对这里出了什么问题的想法？

Answer 1

您正在将一个numpy函数应用于pandas数据帧。

您可以将数据帧转换为numpy数组并随机播放：

 np.random.shuffle(data.values)

或者您可以使用pandas功能：

data = data.sample(len(data))

Answer 2

我并不是真的了解整个追溯，但对我来说，错误只是因为数据帧不是一个numpy数组。要修复它，只需使用$json = str_replace("\"", "", $json);。

使用数据框的实际底层数组

我对回溯中发生的事情的猜测是data.values不检查输入是否是有效数组并尝试操作并从数据帧中获取数据的方式与常规数组相同，因此所有有关np.random.shuffle等的错误。

尝试随机化数据集时出现奇怪的错误

2 个答案: