Running examples in ‘mlr3viz-Ex.R’ failed
The error most likely occurred in:

> ### Name: autoplot.BenchmarkResult
> ### Title: Plot for BenchmarkResult
> ### Aliases: autoplot.BenchmarkResult
> 
> ### ** Examples
> 
> library(mlr3)
> library(mlr3viz)
> 
> tasks = tsks(c("spam", "pima", "sonar"))
> learner = lrns(c("classif.featureless", "classif.rpart"),
+   predict_type = "prob")
> resampling = rsmps("cv")
> object = benchmark(benchmark_grid(tasks, learner, resampling))
INFO  [21:13:03.346] Benchmark with 60 resampling iterations 
INFO  [21:13:03.555] Applying learner 'classif.featureless' on task 'spam' (iter 1/10) 
INFO  [21:13:03.614] Applying learner 'classif.featureless' on task 'spam' (iter 2/10) 
INFO  [21:13:03.642] Applying learner 'classif.featureless' on task 'spam' (iter 3/10) 
INFO  [21:13:03.665] Applying learner 'classif.featureless' on task 'spam' (iter 4/10) 
INFO  [21:13:03.688] Applying learner 'classif.featureless' on task 'spam' (iter 5/10) 
INFO  [21:13:03.711] Applying learner 'classif.featureless' on task 'spam' (iter 6/10) 
INFO  [21:13:03.733] Applying learner 'classif.featureless' on task 'spam' (iter 7/10) 
INFO  [21:13:03.760] Applying learner 'classif.featureless' on task 'spam' (iter 8/10) 
INFO  [21:13:03.781] Applying learner 'classif.featureless' on task 'spam' (iter 9/10) 
INFO  [21:13:03.814] Applying learner 'classif.featureless' on task 'spam' (iter 10/10) 
INFO  [21:13:03.840] Applying learner 'classif.rpart' on task 'spam' (iter 1/10) 
INFO  [21:13:04.051] Applying learner 'classif.rpart' on task 'spam' (iter 2/10) 
INFO  [21:13:04.508] Applying learner 'classif.rpart' on task 'spam' (iter 3/10) 
INFO  [21:13:04.906] Applying learner 'classif.rpart' on task 'spam' (iter 4/10) 
INFO  [21:13:05.202] Applying learner 'classif.rpart' on task 'spam' (iter 5/10) 
INFO  [21:13:05.362] Applying learner 'classif.rpart' on task 'spam' (iter 6/10) 
INFO  [21:13:05.774] Applying learner 'classif.rpart' on task 'spam' (iter 7/10) 
INFO  [21:13:06.210] Applying learner 'classif.rpart' on task 'spam' (iter 8/10) 
INFO  [21:13:06.385] Applying learner 'classif.rpart' on task 'spam' (iter 9/10) 
INFO  [21:13:06.634] Applying learner 'classif.rpart' on task 'spam' (iter 10/10) 
INFO  [21:13:06.828] Applying learner 'classif.featureless' on task 'pima' (iter 1/10) 
INFO  [21:13:06.850] Applying learner 'classif.featureless' on task 'pima' (iter 2/10) 
INFO  [21:13:06.873] Applying learner 'classif.featureless' on task 'pima' (iter 3/10) 
INFO  [21:13:06.899] Applying learner 'classif.featureless' on task 'pima' (iter 4/10) 
INFO  [21:13:06.923] Applying learner 'classif.featureless' on task 'pima' (iter 5/10) 
INFO  [21:13:06.946] Applying learner 'classif.featureless' on task 'pima' (iter 6/10) 
INFO  [21:13:06.968] Applying learner 'classif.featureless' on task 'pima' (iter 7/10) 
INFO  [21:13:06.993] Applying learner 'classif.featureless' on task 'pima' (iter 8/10) 
INFO  [21:13:07.017] Applying learner 'classif.featureless' on task 'pima' (iter 9/10) 
INFO  [21:13:07.039] Applying learner 'classif.featureless' on task 'pima' (iter 10/10) 
INFO  [21:13:07.067] Applying learner 'classif.rpart' on task 'pima' (iter 1/10) 
INFO  [21:13:07.154] Applying learner 'classif.rpart' on task 'pima' (iter 2/10) 
INFO  [21:13:07.215] Applying learner 'classif.rpart' on task 'pima' (iter 3/10) 
INFO  [21:13:07.259] Applying learner 'classif.rpart' on task 'pima' (iter 4/10) 
INFO  [21:13:07.300] Applying learner 'classif.rpart' on task 'pima' (iter 5/10) 
INFO  [21:13:07.347] Applying learner 'classif.rpart' on task 'pima' (iter 6/10) 
INFO  [21:13:07.398] Applying learner 'classif.rpart' on task 'pima' (iter 7/10) 
INFO  [21:13:07.437] Applying learner 'classif.rpart' on task 'pima' (iter 8/10) 
INFO  [21:13:07.477] Applying learner 'classif.rpart' on task 'pima' (iter 9/10) 
INFO  [21:13:07.517] Applying learner 'classif.rpart' on task 'pima' (iter 10/10) 
INFO  [21:13:07.556] Applying learner 'classif.featureless' on task 'sonar' (iter 1/10) 
INFO  [21:13:07.578] Applying learner 'classif.featureless' on task 'sonar' (iter 2/10) 
INFO  [21:13:07.602] Applying learner 'classif.featureless' on task 'sonar' (iter 3/10) 
INFO  [21:13:07.623] Applying learner 'classif.featureless' on task 'sonar' (iter 4/10) 
INFO  [21:13:07.643] Applying learner 'classif.featureless' on task 'sonar' (iter 5/10) 
INFO  [21:13:07.663] Applying learner 'classif.featureless' on task 'sonar' (iter 6/10) 
INFO  [21:13:07.684] Applying learner 'classif.featureless' on task 'sonar' (iter 7/10) 
INFO  [21:13:07.706] Applying learner 'classif.featureless' on task 'sonar' (iter 8/10) 
INFO  [21:13:07.727] Applying learner 'classif.featureless' on task 'sonar' (iter 9/10) 
INFO  [21:13:07.747] Applying learner 'classif.featureless' on task 'sonar' (iter 10/10) 
INFO  [21:13:07.769] Applying learner 'classif.rpart' on task 'sonar' (iter 1/10) 
INFO  [21:13:07.841] Applying learner 'classif.rpart' on task 'sonar' (iter 2/10) 
INFO  [21:13:07.914] Applying learner 'classif.rpart' on task 'sonar' (iter 3/10) 
INFO  [21:13:07.979] Applying learner 'classif.rpart' on task 'sonar' (iter 4/10) 
INFO  [21:13:08.049] Applying learner 'classif.rpart' on task 'sonar' (iter 5/10) 
INFO  [21:13:08.115] Applying learner 'classif.rpart' on task 'sonar' (iter 6/10) 
INFO  [21:13:08.179] Applying learner 'classif.rpart' on task 'sonar' (iter 7/10) 
INFO  [21:13:08.281] Applying learner 'classif.rpart' on task 'sonar' (iter 8/10) 
INFO  [21:13:08.372] Applying learner 'classif.rpart' on task 'sonar' (iter 9/10) 
INFO  [21:13:08.489] Applying learner 'classif.rpart' on task 'sonar' (iter 10/10) 
INFO  [21:13:08.553] Finished benchmark 
> 
> head(fortify(object))
Error: $ operator is invalid for atomic vectors
Execution halted