Running examples in ‘DMwR-Ex.R’ failed
The error most likely occurred in:

> base::assign(".ptime", proc.time(), pos = "CheckExEnv")
> ### Name: compAnalysis
> ### Title: Analyse and print the statistical significance of the
> ###   differences between a set of learners.
> ### Aliases: compAnalysis
> ### Keywords: models
> 
> ### ** Examples
> 
> ## Estimating several evaluation metrics on different variants of a
> ## regression tree on  a data set, using one repetition of 10-fold CV
> data(swiss)
> 
> ## First the user defined functions 
> cv.rpartXse <- function(form, train, test, ...) {
+     require(DMwR)
+     t <- rpartXse(form, train, ...)
+     p <- predict(t, test)
+     mse <- mean((p - resp(form, test))^2)
+     c(nmse = mse/mean((mean(resp(form, train)) - resp(form, test))^2), 
+         mse = mse)
+ }
> 
> results <- experimentalComparison(
+                c(dataset(Infant.Mortality ~ ., swiss)),
+                c(variants('cv.rpartXse',se=c(0,0.5,1))),
+                cvSettings(1,10,1234)
+                                  )


#####  CROSS VALIDATION  EXPERIMENTAL COMPARISON #####

** DATASET :: swiss

++ LEARNER :: cv.rpartXse  variant ->  cv.rpartXse.v1 

 1 x 10 - Fold Cross Validation run with seed =  1234 
Repetition  1 
Fold:  1  2  3  4  5  6  7  8  9  10


++ LEARNER :: cv.rpartXse  variant ->  cv.rpartXse.v2 

 1 x 10 - Fold Cross Validation run with seed =  1234 
Repetition  1 
Fold:  1  2  3  4  5  6  7  8  9  10


++ LEARNER :: cv.rpartXse  variant ->  cv.rpartXse.v3 

 1 x 10 - Fold Cross Validation run with seed =  1234 
Repetition  1 
Fold:  1  2  3  4  5  6  7  8  9  10
> 
> ## Testing the statistical significance of the differences
> compAnalysis(results)
Warning in wilcox.test.default(comp@foldResults[, s, m, d], comp@foldResults[,  :
  cannot compute exact p-value with zeroes
Warning in wilcox.test.default(comp@foldResults[, s, m, d], comp@foldResults[,  :
  cannot compute exact p-value with zeroes
Error in `[[<-.data.frame`(`*tmp*`, i, value = c(1.45684431214828, NA)) : 
  replacement has 2 rows, data has 1
Calls: compAnalysis ... [<-.data.frame -> xpdrows.data.frame -> [[<- -> [[<-.data.frame
Execution halted