To submit to CRAN we cannot use more than 2 threads in our examples/vignettes

R-package/man/xgb.plot.importance.Rd

@@ -31,7 +31,7 @@ data(agaricus.train, package='xgboost')
 train <- agaricus.train
 
 bst <- xgboost(data = train$data, label = train$label, max.depth = 2,
-               eta = 1, nround = 2,objective = "binary:logistic")
+               eta = 1, nthread = 2, nround = 2,objective = "binary:logistic")
 
 #train$data@Dimnames[[2]] represents the column names of the sparse matrix.
 importance_matrix <- xgb.importance(train$data@Dimnames[[2]], model = bst)