Date information disappears when save to CSV

问题

I am trying to pull some data in from the internet and then export it to a CSV file, but I am loosing my date information in the CSV file. I can't figure out why. I'm new to R so please keep responses simple. Here is my code:

Library(quantmod)
getSymbols("SPY", from = "2012-01-01", to = "2012-12-31")
write.csv(SPY, "C:/SPY.csv")

回答1:

as SPY is a xts/zoo object this will do the trick:

replace:

write.csv(SPY, "C:/SPY.csv")

with

write.zoo(SPY,"C:/SPY.csv",index.name="Date",sep=",")

回答2:

Try:

write.csv(SPY, file= "SPY.csv", row.names = index(SPY))

回答3:

Are you sure that the date information is being lost? If you are using MS-Excel to open the .CSV, it may be that Excel is munging your data.

回答4:

If you do str(SPY) you get to see the inner structure of your xts object. The dates are in the index, not in the main data.

I use these three lines to save an xts object as a csv file:

#Convert to a data frame so it can be written to disk
d=as.data.frame(SPY)
d=cbind(datestamp=rownames(d),d)
write.csv(d,file="SPY.csv",row.names=F)

来源：https://stackoverflow.com/questions/15796499/date-information-disappears-when-save-to-csv