我正在获取数据，尝试迭代数据并逐行添加。试图获取每家公司的股票数据(单行)

Question

，我试图迭代数据，获取数据并逐行添加数据。试图获取每个公司的股票数据(单行)

守则如下：

df = pdr.get_data_yahoo('ABB.NS', start = "2021-6-2", end = "2021-6-3")
df

产出如下：

            Open    High    Low Close   Adj Close   Volume
Date                        
2021-06-02  1698.0  1717.0  1668.0  1700.55 1700.55 314707

类似地，我已经列出了公司名称，并希望获取公司的一行并逐行添加它们.

清单是

sym = symbol[:5]
sym

产出如下：

['20MICRONS.NS', '21STCENMGM.NS', '3IINFOTECH.NS', '3MINDIA.NS', '3PLAND.NS']

我正在尝试的代码是

for i in sym:
    df = pdr.get_data_yahoo(i, start = "2021-6-2", end = "2021-6-3")

产出如下：

            Open    High    Low Close   Adj Close   Volume
Date                        
2021-06-02  14.05   14.05   13.25   13.5    13.5    3861

预期产出如下：

            Open    High    Low Close   Adj Close   Volume
Date                        
2021-06-02  14.05   14.05   13.25   13.5    13.5    3861
"           Other   Other   Other   Other   Other   Other
"           Other   Other   Other   Other   Other   Other
"           Other   Other   Other   Other   Other   Other
"           Other   Other   Other   Other   Other   Other

Other are the stock values according to the companies

输出仅为单行。我试图获得5行，因为我正在迭代5个公司名称。

如果公司没有特定日期的数据，则返回错误如下

Exception in thread Thread-96:
Traceback (most recent call last):
  File "c:\python37\lib\threading.py", line 926, in _bootstrap_inner
    self.run()
  File "c:\python37\lib\threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
  File "C:\Users\venka\all\lib\site-packages\multitasking\__init__.py", line 102, in _run_via_pool
    return callee(*args, **kwargs)
  File "C:\Users\venka\all\lib\site-packages\fix_yahoo_finance\__init__.py", line 322, in _download_one_threaded
    period, interval, prepost)
  File "C:\Users\venka\all\lib\site-packages\fix_yahoo_finance\__init__.py", line 333, in _download_one
    actions=actions, auto_adjust=auto_adjust)
  File "C:\Users\venka\all\lib\site-packages\fix_yahoo_finance\__init__.py", line 246, in history
    raise ValueError(self.ticker, err_msg)
ValueError: ('ANMOL.NS', 'No data found, symbol may be delisted')

特定日期不存在ANMOL.NS符号公司数据。如何在这些地方给出空值？

Answer 1

get_data_yahoo可以将列表作为输入，然后将stack转换为长格式：

sym = ['20MICRONS.NS', '21STCENMGM.NS', '3IINFOTECH.NS', '3MINDIA.NS',
       '3PLAND.NS']
df = pdr.get_data_yahoo(sym, start="2021-6-2", end="2021-6-3").stack()

df

Attributes                   Adj Close         Close          High           Low          Open    Volume
Date       Symbols                                                                                      
2021-06-02 20MICRONS.NS      60.700001     60.700001     61.900002     59.500000     59.950001    374552
           21STCENMGM.NS     15.650000     15.650000     15.650000     15.250000     15.250000      1810
           3IINFOTECH.NS      9.200000      9.200000      9.300000      8.650000      8.850000  39107857
           3MINDIA.NS     25967.199219  25967.199219  26000.000000  25543.750000  25640.000000      3698
           3PLAND.NS         13.500000     13.500000     14.050000     13.250000     14.050000      3861
2021-06-03 20MICRONS.NS      62.549999     62.549999     64.349998     61.099998     62.250000    401022
           21STCENMGM.NS     15.950000     15.950000     15.950000     15.950000     15.950000       949
           3IINFOTECH.NS      8.950000      8.950000      9.250000      8.900000      9.200000  17823524
           3MINDIA.NS     26261.800781  26261.800781  26300.000000  25900.000000  25967.199219      2713
           3PLAND.NS         13.950000     13.950000     14.100000     13.400000     14.000000     19728

(可选的reset_index将MultiIndex转换为列)

df = (
    pdr.get_data_yahoo(sym, start="2021-6-2", end="2021-6-3")
        .stack()
        .reset_index()
)

df

Attributes       Date        Symbols     Adj Close         Close          High           Low          Open    Volume
0          2021-06-02   20MICRONS.NS     60.700001     60.700001     61.900002     59.500000     59.950001    374552
1          2021-06-02  21STCENMGM.NS     15.650000     15.650000     15.650000     15.250000     15.250000      1810
2          2021-06-02  3IINFOTECH.NS      9.200000      9.200000      9.300000      8.650000      8.850000  39107857
3          2021-06-02     3MINDIA.NS  25967.199219  25967.199219  26000.000000  25543.750000  25640.000000      3698
4          2021-06-02      3PLAND.NS     13.500000     13.500000     14.050000     13.250000     14.050000      3861
5          2021-06-03   20MICRONS.NS     62.549999     62.549999     64.349998     61.099998     62.250000    401022
6          2021-06-03  21STCENMGM.NS     15.950000     15.950000     15.950000     15.950000     15.950000       949
7          2021-06-03  3IINFOTECH.NS      8.950000      8.950000      9.250000      8.900000      9.200000  17823524
8          2021-06-03     3MINDIA.NS  26261.800781  26261.800781  26300.000000  25900.000000  25967.199219      2713
9          2021-06-03      3PLAND.NS     13.950000     13.950000     14.100000     13.400000     14.000000     19728

对顺序读取的显式错误处理：

import pandas as pd
import pandas_datareader as pdr
from pandas_datareader._utils import RemoteDataError

sym = ['20MICRONS.NS', '21STCENMGM.NS', '3IINFOTECH.NS', '3MINDIA.NS',
       '3PLAND.NS', 'ANMOL.NS']

dfs = []
for s in sym:
    try:
        dfs.append(pdr.get_data_yahoo(s, start="2021-6-2", end="2021-6-3"))
    except RemoteDataError:
        print(f'{s} could not be resolved')

df = pd.concat(dfs)

print(df)

输出：

ANMOL.NS could not be resolved
                    High           Low  ...    Volume     Adj Close
Date                                    ...                        
2021-06-02     61.900002     59.500000  ...    374552     60.700001
2021-06-03     64.349998     61.099998  ...    401022     62.549999
2021-06-02     15.650000     15.250000  ...      1810     15.650000
2021-06-03     15.950000     15.950000  ...       949     15.950000
2021-06-02      9.300000      8.650000  ...  39107857      9.200000
2021-06-03      9.250000      8.900000  ...  17823524      8.950000
2021-06-02  26000.000000  25543.750000  ...      3698  25967.199219
2021-06-03  26300.000000  25900.000000  ...      2713  26261.800781
2021-06-02     14.050000     13.250000  ...      3861     13.500000
2021-06-03     14.100000     13.400000  ...     19728     13.950000

Answer 2

在for-循环的每一次迭代中，都会覆盖前面的'df‘值。解决办法之一是：

df_list = []
for i in sym:
    df_list.append(pdr.get_data_yahoo(i, start = "2021-6-2", end = "2021-6-3"))
df = pd.concat(df_list, axis=0)

编辑:我看到你有‘日期’作为df的索引。您将需要玩这个，以便您的最终df是有意义的。