character variable as parameter of function
part of my code for downloading financial data:
library(quantmod)
tickers <- c("XOM", "DIS")
stock1 <- getSymbols(tickers[1], from="2010-03-01", to="2011-02-28", auto.assign=F)
stock2 <- getSymbols(tickers[2], from="2010-03-01", to="2011-02-28", auto.assign=F)
pair <- merge(Ad(stock1), Ad(stock2), all=F) # 'xts' object, merge adjusted close
pair.DF <- data.frame(pair) # data frame
But I want to call function like this:
tickers <- function(x, y) {
stock1 <- getSymbols(x, from="2010-03-01", to="2011-02-28", auto.assign=F)
stock2 <- getSymbols(y, from="2010-03-01", to="2011-02-28", auto.assign=F)
pair <- merge(Ad(stock1), Ad(stock2), all=F)
pair.DF <- data.frame(pair)
}
And then:
tickers("XOM", "DIS")
Or something similar. But what I get is bad result. In this case "x" and "y" aren´t numer开发者_StackOverflow中文版ic, but character. It seems to be easy, but.. Thanks for any suggestions.
tickers <- function(x, y) {
stock1 <- getSymbols(x, from="2010-03-01", to="2011-02-28", auto.assign=F)
stock2 <- getSymbols(y, from="2010-03-01", to="2011-02-28", auto.assign=F)
pair <- merge(Ad(stock1), Ad(stock2), all=F)
pair.DF <- data.frame(pair)
return(pair.DF)
}
Works for me as long as you return the pair.DF at the end. Is that your problem?
I don't think the character class is the problem:
class(tickers[1])==class("XOM")
TRUE
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