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合并数据帧的列时出错

merge dataframe pandas string python

aabujamra · 技术社区 · 8 年前

                 Telefone1   Telefone2
CNPJ                                  
44167450000149  1332385314  1332385314
56095862000108  2125439090  2125439090
59664391000191  1143990005  1143990005

我想把“Telefone1”和“Telefone2”合并到一个列中。它应该是这样的:

                Telefone
CNPJ                                  
44167450000149  1332385314,1332385314
56095862000108  2125439090,2125439090
59664391000191  1143990005,1143990005

df['Telefone']=df.Telefone1.astype(str)+","+df.Telefone2.astype(str)

我得到了这个回溯:

Traceback (most recent call last):
File "/file.py", line 507, in <module>
'file')
File "file.py", line 347, in function
df['Telefone']=df.Telefone1.astype(str)+","+df.Telefone2.astype(str)
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pandas/core/frame.py", line 2357, in __setitem__
self._set_item(key, value)
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pandas/core/frame.py", line 2424, in _set_item
NDFrame._set_item(self, key, value)
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pandas/core/generic.py", line 1464, in _set_item
self._data.set(key, value)
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pandas/core/internals.py", line 3418, in set
self.insert(len(self.items), item, value)
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pandas/core/internals.py", line 3519, in insert
placement=slice(loc, loc + 1))
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pandas/core/internals.py", line 2518, in make_block
return klass(values, ndim=ndim, fastpath=fastpath, placement=placement)
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pandas/core/internals.py", line 1663, in __init__
placement=placement, **kwargs)
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pandas/core/internals.py", line 90, in __init__
len(self.mgr_locs)))
ValueError: Wrong number of items passed 4, placement implies 1

我做错了什么?

3 回复 | 直到 8 年前

Alexander 8 年前

>>> (df.iloc[:, 0].astype(str) + ',' + df.iloc[:, 1].astype(str)).to_frame('Telephone')
                             Telefone
CNPJ                                 
44167450000149  1332385314,1332385314
56095862000108  2125439090,2125439090
59664391000191  1143990005,1143990005

(df.loc[:, 'Telefone1'].astype(str) + ',' + df.loc[:, 'Telefone2'].astype(str)).to_frame('Telefone'))

这适用于您的示例数据。如果有错误,请创建一个新列来指示每个字段的长度,并根据此值排序。可能会出现数据错误。

cs95 abhishek58g 8 年前

df = df.applymap(str)

选项1

str.cat

df = pd.DataFrame({'Telefone' : df.Telefone1.str.cat(df.Telefone2, sep=',')}, index=df.index)
df
                             Telefone
CNPJ                                 
44167450000149  1332385314,1332385314
56095862000108  2125439090,2125439090
59664391000191  1143990005,1143990005

df.apply

df = df.apply(','.join, 1).to_frame(name='Telefone')
df 
                             Telefone
CNPJ                                 
44167450000149  1332385314,1332385314
56095862000108  2125439090,2125439090
59664391000191  1143990005,1143990005

Def_Os 8 年前

使用字符串访问器的cat()函数:

df = df.astype(str)
df['Telefone'] = df['Telefone1'].str.cat(df['Telefone2'])