'data' added and internal function 'checkClass' added.

R/checkClass.R

@@ -0,0 +1,23 @@
+#' 
+#' @title Checks that an object has the same class in all studies
+#' @description This is an internal function.
+#' @details In DataSHIELD an object included in analysis must be of the same type in all 
+#' the collaborating studies. If that is not the case the process is stopped
+#' @param datasources a list of opal object(s) obtained after login in to opal servers;
+#' these objects hold also the data assign to R, as \code{dataframe}, from opal datasources.
+#' @param obj a string charcater, the name of the object to check for.
+#' @keywords internal
+#' @return a message or the class of the object if the object has the same class in all studies.
+#'
+checkClass <- function(datasources=NULL, obj=NULL){
+  # check the class of the input object
+  cally <- paste0("class(", obj, ")")
+  objtype <- unique(unlist(datashield.aggregate(datasources, cally)))
+  if(length(objtype) > 1){
+    message("The input data is not of the same class in all studies!")
+    message("Use the function 'ds.class' to verify the class of the input object in each study.")
+    stop(" End of process!", call.=FALSE)
+  }else{
+    return(objtype)
+  }
+}

man/checkClass.Rd

@@ -0,0 +1,31 @@
+\name{checkClass}
+\alias{checkClass}
+\title{Checks that an object has the same class in all studies}
+\usage{
+checkClass(datasources = NULL, obj = NULL)
+}
+\arguments{
+  \item{datasources}{a list of opal object(s) obtained
+  after login in to opal servers; these objects hold also
+  the data assign to R, as \code{dataframe}, from opal
+  datasources.}
+
+  \item{obj}{a string charcater, the name of the object to
+  check for.}
+}
+\value{
+a message or the class of the object if the object has the
+same class in all studies.
+}
+\description{
+This is an internal function.
+}
+\details{
+
+
+In DataSHIELD an object included in analysis must be of the
+same type in all the collaborating studies. If that is not
+the case the process is stopped
+}
+\keyword{internal}
+

man/logindata.Rd

@@ -0,0 +1,29 @@
+\name{logindata}
+
+\alias{logindata}
+
+\docType{data}
+
+\title{Information required to login to opal servers}
+
+\description{
+    A table of with 5 columns: study name, URL, username, password and opal datasource.
+}
+
+\usage{data(logindata)}
+
+\format{
+  A data frame where the number of servers corresponds to the number of rows
+  \describe{
+    \item{\code{server}}{a character, the formal name of the study}
+    \item{\code{url}}{URL of the opal server}
+    \item{\code{user}}{a character, a formal username or a 
+          path to a valid ssl certificate, if required}
+    \item{\code{password}}{a character, a formal password or a 
+          path to a valid ssl key if required}
+    \item{\code{table}}{a character, the path to the opal datasource that holds the data
+         to analyse}
+  }
+}
+
+\examples{data(logindata)}