我有一份 SP500 指数中的股票清单。我如何为每只股票分配类别类型?
电流输出:
library(tidyquant)
tq_index('SP500')$symbol
[1] "MSFT" "AAPL" "AMZN" "BRK.B" "FB" [...]
预期的:
symbol type
MSFT Technology
AAPL Technology
AMZN Technology
BRK.B Financials
FB Technology