Question

我正在尝试使用Pandas合并两个不同的csv文件，但这样做会遇到错误。

第一个文件是aapl.csv，如下所示：

          Date   Close      High       Low      Open    Volume
Symbol                                                            
AAPL    2017-05-25  153.87  154.3500  153.0300  153.7300  19235598
AAPL    2017-05-26  153.61  154.2400  153.3100  154.0000  21927637

第二个文件是corr_column.csv，如下所示：

Corr
0.01
0.02

我想以'Corr'在'Volume'之后显示为一列的方式合并它们。

我已尝试使用pd.concat，如文档中所述：

https://pandas.pydata.org/pandas-docs/stable/merging.html

这是我的代码：

import datetime as dt
import matplotlib.pyplot as plt
from matplotlib import style
import pandas as pd
pd.core.common.is_list_like = pd.api.types.is_list_like
import pandas_datareader.data as web
from mpl_finance import candlestick_ohlc
import matplotlib.dates as mdates
from matplotlib.dates import DateFormatter, MonthLocator, YearLocator, DayLocator
style.use( 'ggplot' )


##start = dt.datetime( 2017, 5, 29 )
##end = dt.datetime( 2018, 5, 29 )
##
##
##df = web.DataReader( AAPL, 'morningstar', start, end )
##
##df.to_csv( aapl.csv )

df = pd.read_csv( '/Users/zubairjohal/Documents/aapl.csv' ,         parse_dates=True, index_col=0 )
df_ohlc = df


corr_data = pd.read_csv( '/Users/zubairjohal/Documents/corr_column.csv', parse_dates=True, index_col=0 )


corr_data.dropna( inplace=True )


df.dropna( inplace=True )


merged = pd.concat( [ df, corr_data ], axis=1 )

merged.to_csv( 'combine2.csv', index=False )

print( merged )

但是，在打印时，我遇到了错误，如下所示：

Traceback (most recent call last):
File "/Users/zubairjohal/Documents/nw5.py", line 34, in <module>
merged = pd.concat( [ df, corr_data ], axis=1 )
File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/pandas/core/reshape/concat.py", line 226, in concat
return op.get_result()
File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/pandas/core/reshape/concat.py", line 423, in get_result
copy=self.copy)
File     "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-  packages/pandas/core/internals.py", line 5425, in concatenate_block_managers
return BlockManager(blocks, axes)
File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/pandas/core/internals.py", line 3282, in __init__
self._verify_integrity()
File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/pandas/core/internals.py", line 3493, in _verify_integrity
construction_error(tot_items, block.shape[1:], self.axes)
File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/pandas/core/internals.py", line 4843, in construction_error
passed, implied))
ValueError: Shape of passed values is (6, 68896), indices imply (6, 514)

任何建议，参考或替代方案都将不胜感激。

Answer 1

你可以试试这个：

pd.concat([df_ohlc.reset_index(), corr_data], axis=1).set_index("Symbol")

输出：

        Close        Date    High     Low    Open      Volume  Corr
Symbol                                                              
AAPL   153.87  2017-05-25  154.35  153.03  153.73  19235598.0  0.01
AAPL   153.61  2017-05-26  154.24  153.31  154.00  21927637.0  0.02

如果您的数据框与AAPL作为索引并且没有索引的corr打印df_ohlc的方式相同，则此方法有效。

使用Pandas合并两个CSV文件

1 个答案: