Add try around DIF table

Author: koenderks

R/itemresponsetheorycommon.R

@@ -985,8 +985,14 @@
     tb$setError(gettext("DIf-analysis not possible: Select at least one parameter to test."))
     return()
   }
-  fit <- mirt::multipleGroup(data = state[["items"]], model = 1, itemtype = options[["model"]], group = dataset[[options[["groupingVariable"]]]], SE = FALSE, verbose = FALSE, TOL = options[["emTolerance"]], technical = list(NCYCLES = options[["emIterations"]], set.seed = options[["seed"]]))
-  dif <- mirt::DIF(fit, which.par = parameters)
+  result <- try{(
+    fit <- mirt::multipleGroup(data = state[["items"]], model = 1, itemtype = options[["model"]], group = dataset[[options[["groupingVariable"]]]], SE = FALSE, verbose = FALSE, TOL = options[["emTolerance"]], technical = list(NCYCLES = options[["emIterations"]], set.seed = options[["seed"]]))
+    dif <- mirt::DIF(fit, which.par = parameters)
+  )}
+  if (jaspBase:::isTryError(result)) {
+    tb$setError(jaspBase:::.extractErrorMessage(result))
+    return()
+  }
   tb[["item"]] <- options[["items"]]
   tb[["aic"]] <- dif[["AIC"]]
   tb[["sabic"]] <- dif[["SABIC"]]