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 pdimport pandas_datareader.data as web #grabs stock dataimport datetime as dt #to specify date range for grab#VARS:#url to f500 listdata_url = "https://query.data.world/s/vjghzuarkh6dap3dblkxanppyh5jtl" source = "yahoo" start = dt.datetime(2019, 2, 13) #datetime typeend = dt.datetime.now()    results = []#read into memorydf500 = 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()