R 循环并从 yahoo.com 下载股票价格

Question

我正在尝试一次从雅虎下载多股股票的价格。我尝试了以下代码，它产生了结果，但我希望结果以每股列的形式呈现。

所以:

library(tseries)
library(zoo)

ticker<-c('AAPL', 'MSFT', 'GOOG')

nShares<-length(ticker)

start<-'2015-01-01'

end<-'2015-09-01'

prices <- function() {

    y=get.hist.quote(instrument = ticker[i],
               start = start,
               end = end, quote = "AdjClose",
               retclass = "zoo")

   dimnames(y)[[2]] <- as.character(ticker[i])
   print (y)
  }  

for (i in 1:nShares){
  prices()
}

我得到的结果是一列包含 3 股的所有时间序列。我希望将它们全部分成 3 列:

Date              AAPL     MSFT    GOOG

2015-xx-xx      xx.xx    xx.xx   xx.xx

我怎样才能做到这一点？

Answer 1

稍微修改一下你的函数:

prices <- function(ticker, start, end) {

  y=get.hist.quote(instrument = ticker,
                   start = start,
                   end = end, quote = "AdjClose",
                   retclass = "zoo")

  dimnames(y)[[2]] <- as.character(ticker)
  # print (y)
  y
} 

只需 1 行即可实现:

zoo_group <- do.call(cbind, lapply(tickers, prices, start=start, end=end))
head(zoo_group)
               AAPL     MSFT     GOOG
2015-01-02 107.9586 45.82758 524.8124
2015-01-05 104.9172 45.40616 513.8723
2015-01-06 104.9271 44.73971 501.9623
2015-01-07 106.3984 45.30815 501.1023
2015-01-08 110.4864 46.64103 502.6823
2015-01-09 110.6049 46.24900 496.1723