python - 如何从数据框中提取特定值？

Question

我正在从雅虎抓取数据，并尝试使用另一个文件上的值从其数据框中提取特定值。

我已经设法抓取数据并将其显示为数据框。问题是我正在尝试使用另一个 df 从数据中提取特定值。

这是我得到的 csv

df_earnings=pd.read_excel(r"C:Earnings to Update.xlsx",index_col=2)
stock_symbols = df_earnings.index

输出:

             Date        E Time           Company Name
Stock Symbol                                                
CALM         2019-04-01  Before The Open     Cal-Maine Foods
CTRA         2019-04-01  Before The Open      Contura Energy
NVGS         2019-04-01  Before The Open  Navigator Holdings
ANGO         2019-04-02  Before The Open       AngioDynamics
LW           2019-04-02  Before The Open         Lamb Weston`

然后我使用雅虎财经的数据下载每只股票的 csv:

driver.get(f'https://finance.yahoo.com/quote/{stock_symbol}/history?period1=0&period2=2597263000&interval=1d&filter=history&frequency=1d')

输出:

            Open     High     Low        ...       Adj Close Volume  Stock Name
Date                                     ...                                    
1996-12-12  1.81250  1.8125  1.68750     ...       0.743409  1984400        CALM
1996-12-13  1.71875  1.8125  1.65625     ...       0.777510   996800        CALM
1996-12-16  1.81250  1.8125  1.71875     ...       0.750229   122000        CALM
1996-12-17  1.75000  1.8125  1.75000     ...       0.774094   239200        CALM
1996-12-18  1.81250  1.8125  1.75000     ...       0.791151   216400        CALM

我的问题是我不知道如何从我的数据框中找到日期并从下载的文件中提取它。

现在我不想插入这样的手动日期:

df = pd.DataFrame.from_csv(file_path)
df['Stock Name'] = stock_symbol
print(df.head())

df = df.reset_index()
print(df.loc[df['Date'] == '2019-04-01'])

输出:

     Date        Open       High   ...  Adj Close  Volume  Stock Name
5610 2019-04-01  46.700001  47.0   ...  42.987827  846900  CALM

我想要一个条件来运行每只股票的数据框并提取所需的日期

print(df.loc[df['Date'] == the date that is next to the symbol that i just downloaded the file for])

Answer 1

我想您可以使用变量来保存日期。

for sy in stock_symbols:
    # The value from the 'Date' column in df_earnings
    dt = df_earnings.loc[df_earnings.index == sy, 'Date'][sy]

    # From the second block of your code relating to 'manual' date
    df = pd.DataFrame.from_csv(file_path)
    df['Stock Name'] = sy
    df = df.reset_index()
    print(df.loc[df['Date'] == dt])