Python .apply（pd.to_numeric）返回错误消息_Python

Python .apply（pd.to_numeric）返回错误消息

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Python .apply（pd.to_numeric）返回错误消息,python,Python,我有一个带有两列的数据框，我想转换成数字类型。我使用以下代码： df[["GP","G"]]=df[["GP","G"]].apply(pd.to_numeric) Python返回以下错误消息： File "C:\Users\Alexandros_7\Anaconda3\lib\site-packages\pandas\core\frame.py", line 4157, in _apply_standard results[i] = func(v) File "C:\Users\Alex

我有一个带有两列的数据框，我想转换成数字类型。我使用以下代码：

df[["GP","G"]]=df[["GP","G"]].apply(pd.to_numeric)

Python返回以下错误消息：

File "C:\Users\Alexandros_7\Anaconda3\lib\site-packages\pandas\core\frame.py", line 4157, in _apply_standard
results[i] = func(v)

File "C:\Users\Alexandros_7\Anaconda3\lib\site-packages\pandas\tools\util.py", line 115, in to_numeric
coerce_numeric=coerce_numeric)

File "pandas\src\inference.pyx", line 612, in pandas.lib.maybe_convert_numeric (pandas\lib.c:53558)

File "pandas\src\inference.pyx", line 598, in      pandas.lib.maybe_convert_numeric (pandas\lib.c:53344)

ValueError: ('Unable to parse string', 'occurred at index GP')

我如何解决这个问题？如何使用命令一次转换多个列类型？谢谢大家!

只有当所有数据都可以解析为数字时，代码才会工作

如果不是，则dataframe中至少有一个值不能转换为数值。在这种情况下，您可以根据自己的选择使用errors参数。这里有一个例子

>>> df = pd.DataFrame({'A' : list('aabbcd'), 'B' : list('ffghhe')})

>>> df
   A  B
0  a  f
1  a  f
2  b  g
3  b  h
4  c  h
5  d  e

>>> df.apply(pd.to_numeric, errors='ignore')
   A  B
0  a  f
1  a  f
2  b  g
3  b  h
4  c  h
5  d  e

>>> df.apply(pd.to_numeric, errors='coerce')
    A   B
0 NaN NaN
1 NaN NaN
2 NaN NaN
3 NaN NaN
4 NaN NaN
5 NaN NaN

>>> df.apply(pd.to_numeric, errors='raise')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/dist-packages/pandas/core/frame.py", line 4042, in apply
    return self._apply_standard(f, axis, reduce=reduce)
  File "/usr/local/lib/python2.7/dist-packages/pandas/core/frame.py", line 4138, in _apply_standard
    results[i] = func(v)
  File "/usr/local/lib/python2.7/dist-packages/pandas/core/frame.py", line 4020, in f
    return func(x, *args, **kwds)
  File "/usr/local/lib/python2.7/dist-packages/pandas/tools/util.py", line 98, in to_numeric
    coerce_numeric=coerce_numeric)
  File "pandas/src/inference.pyx", line 612, in pandas.lib.maybe_convert_numeric (pandas/lib.c:53932)
  File "pandas/src/inference.pyx", line 598, in pandas.lib.maybe_convert_numeric (pandas/lib.c:53719)
ValueError: ('Unable to parse string', u'occurred at index A')
>>>

以下是错误的文档

错误：{'ignore'，'raise'，'concurve'，}，默认值为'raise'

如果为“raise”，则无效解析将引发异常

如果为“强制”，则无效解析将设置为NaN

如果为“忽略”，则无效解析将返回输入

只有当所有数据都可以解析为数字时，代码才能工作