涉及动态数据帧对象的嵌套 Pandas iterrows

Question

我的脚本接收 F500 公司的“实时”在线列表，遍历每个股票代码，获取指定时间段内的股票代码表现。我无法弄清楚的是如何将模式/存储到 2D 列表中，每个符号的多行代码数据。不知何故，第二个 iterrows 将不起作用。提前致谢：

import pandas as pd #dataframe extends from pd

import pandas_datareader.data as web #grabs stock data

import datetime as dt #to specify date range for grab

#VARS:

#url to f500 list

data_url = "https://query.data.world/s/vjghzuarkh6dap3dblkxanppyh5jtl" 

source = "yahoo" 

start = dt.datetime(2019, 2, 13) #datetime type

end = dt.datetime.now()    

results = []

#read into memory

df500 = pd.read_csv(data_url)

for index, row in df500.tail().iterrows(): 

    try:

        dfdr = web.DataReader(row['SYMBOL'], source, start, end) #returns a dataframe presumably

        for index2, row2 in dfdr().iterrows(): 

            # here i want to append to the results list: row['SYMBOL'], row2['Date'], row2['High']

            print ("test output ", row2[0]) #not even this works

    except Exception as e: 

        pass

# commit to sqlite3 from list or df

Answer 1

这里dfdr后面的括号是错误的：dfdr().iterrows()应该：dfdr.iterrows()