Peter, Here is the R command and its output that you requested:
> class(AVB) [1] "xts" "zoo" Bob On 8/9/2018 5:29 PM, Peter Langfelder wrote:
Well, your function uses AVB$AVB.Close, so I assumed AVB is a list (a data frame can be thought of as a special list). What do you get when you type class(AVB)? Peter On Thu, Aug 9, 2018 at 2:24 PM rsherry8 <[email protected]> wrote:Peter, Thanks for the response. I tired the following command: AVB[["AVB.Close"]] and I got: Error in AVB[["AVB.Close"]] : subscript out of bounds Are you assuming that AVB is a data frame? I do not think AVB is a data frame. Is there a way for me to check? Thanks, Bob On 8/9/2018 3:46 PM, Peter Langfelder wrote:If I understand it correctly, the function getSymbols creates a variable with the name being the stock symbol. Then use the function get(symbol) to retrieve the value of the variable whose name is contained in the character string `symbol'. Assign that to a variable (e.g. AVB). You may also have to modify the names of the components you retrieve from the list AVB. For that, you can use AVB[["AVB.Close"]] instead of AVB$AVB.Close. You can them use something like AVB[[paste0(symbol, ".Close"]] to generalize the retrieval of list components. HTH, Peter On Thu, Aug 9, 2018 at 12:40 PM rsherry8 <[email protected]> wrote:I wrote the following function: # This method gets historical stock data for the stock Avalon Bay whose symbol is AVB. getReturns <- function(norm = FALSE) { library(quantmod) getSymbols("AVB", src = "yahoo", from = start, to = end) length = length( AVB$AVB.Close ) close = as.numeric( AVB$AVB.Close ) cat( "length = ", length(close ), "\n" ) for( i in 1:length-1 ) diff[i] = ((close[i+1] - close[i]) ) / close[i] u = mean(diff) stdDev = sd(diff) cat( "stdDev = ", stdDev, "\n" ) if ( norm == TRUE ) { diff = (diff - u) diff = diff / stdDev } return (diff) } I would like to generalize it to work for any stock by passing in the stock symbol. So the header for the function would be: getReturns <- function(symbol, norm = FALSE) Now how do I update this line: length = length( AVB$AVB.Close ) This statement will not work: length = length( symbol$AVB.Close ) because the name that holds the closing price is a function of the stock symbol. Thanks, Bob ______________________________________________ [email protected] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
______________________________________________ [email protected] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
