Get the stock prices with the help of an R loop-CodePudding

I'm a beginner in R programming and I need some help for a class assignment:

In fact I need to extract the stock prices with a FOR loop (its use is manadatory)

So I've tried the following:

options(digits=4, width=70)
install.packages("PerformanceAnalytics")
install.packages("tseries")
install.packages("zoo")
library("PerformanceAnalytics")
library("tseries")
library("zoo")

stocks<- c("AAPL","MSFT","AMZN","TSLA","NVDA","UNH","JNJ","JPM","XOM","CVX")

for(i in stocks)
  {
  stock.prices <- get.hist.quote(instrument=i, start="2010-01-01",
                                 end="2020-01-31", quote="AdjClose",
                                 provider="yahoo", origin="2000-01-09",
                                 compression="m", ret)
}

and I'm getting the values for "CVX" only which is quite normal since each stock is discarding the previous one.

I need to pull the data into the following shape to be ale to analyze it.

               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

I've found several solutions that work without the R loop but it is mandatory for my assignment to use it.

Thank you in advance for your help.

CodePudding user response：

Sticking as closely as possible to your existing solution, the main issue is that you need to store each iteration of the loop somewhere (below, in a list called stocks.dl. Once you have that, you can combine them with merge.zoo:

library("PerformanceAnalytics")
library("tseries")
library("zoo")

stocks<- c("AAPL","MSFT","AMZN","TSLA","NVDA","UNH","JNJ","JPM","XOM","CVX")
stocks.dl <- list()
for(i in stocks) {
  stocks.dl[[i]] <- get.hist.quote(instrument=i, start="2010-01-01",
                                 end="2020-01-31", quote="AdjClose",
                                 provider="yahoo", origin="2000-01-09",
                                 compression="m", ret)
  
  dimnames(stocks.dl[[i]])[[2]] <- i # update column name to match the stock name
  
}

data.stocks <- do.call(merge.zoo, stocks.dl)

               AAPL     MSFT   AMZN TSLA     NVDA      UNH      JNJ
2010-01-01 5.873429 21.72060 125.41   NA 3.533751 27.46159 43.88154
2010-02-01 6.257530 22.09827 118.40   NA 3.719738 28.17724 43.97926
2010-03-01 7.186587 22.68174 135.77   NA 3.995275 27.18697 45.86330
2010-04-01 7.984451 23.64971 137.10   NA 3.607228 25.22305 45.23025
2010-05-01 7.855704 19.97913 125.46   NA 3.017121 24.21340 41.00968
2010-06-01 7.692095 17.89899 109.26   NA 2.344354 23.65532 41.92373