Fixed xml option to handles multiple sites better.

R/retrieveNWISData.r

@@ -4,7 +4,7 @@
 #' A list of parameter codes can be found here: \url{http://help.waterdata.usgs.gov/codes-and-parameters/parameters}
 #' A list of statistic codes can be found here: \url{http://help.waterdata.usgs.gov/code/stat_code_query?fmt=html}
 #'
-#' @param siteNumber string USGS site number.  This is usually an 8 digit number
+#' @param siteNumber string USGS site number.  This is usually an 8 digit number. Multiple sites can be requested with a string vector.
 #' @param parameterCd string or vector of USGS parameter code.  This is usually an 5 digit number..
 #' @param startDate string starting date for data retrieval in the form YYYY-MM-DD.
 #' @param endDate string ending date for data retrieval in the form YYYY-MM-DD.
@@ -29,13 +29,15 @@
 #'        startDate, endDate, statCd='00001',format='tsv')
 #' rawDailyQAndTempMeanMax <- retrieveNWISdvData(siteNumber,c('00010','00060'),
 #'        startDate, endDate, statCd=c('00001','00003'))
+#' rawDailyMultiSites<- retrieveNWISdvData(c("01491000","01645000"),c('00010','00060'),
+#'        startDate, endDate, statCd=c('00001','00003'))
 retrieveNWISdvData <- function (siteNumber,parameterCd,startDate,endDate,statCd="00003",format="tsv",interactive=TRUE){  
   
   url <- constructNWISURL(siteNumber,parameterCd,startDate,endDate,"dv",statCd=statCd,format=format,interactive=interactive)
   
   if (format == "xml") {
     data <- getWaterML1Data(url)
-    data$dateTime <- as.Date(data$dateTime)
+    data$datetime <- as.Date(data$datetime)
   } else {
     data <- getRDB1Data(url,asDateTime=FALSE)
   }