[R-package] [docs] Simplified examples to cut example run time (fixes #2988) (#2989)

* [R-package] [docs] Simplified examles to cut example run time (fixes #2988)

* updated learning rates

R-package/man/lightgbm.Rd

@@ -45,7 +45,8 @@ If early stopping occurs, the model will have 'best_iter' field.}
 
 \item{init_model}{path of model file of \code{lgb.Booster} object, will continue training from this model}
 
-\item{callbacks}{List of callback functions that are applied at each iteration.}
+\item{callbacks}{list of callback functions
+List of callback functions that are applied at each iteration.}
 
 \item{...}{Additional arguments passed to \code{\link{lgb.train}}. For example
 \itemize{

R-package/man/predict.lgb.Booster.Rd

@@ -52,7 +52,6 @@ For regression or binary classification, it returns a vector of length \code{nro
 Predicted values based on class \code{lgb.Booster}
 }
 \examples{
-library(lightgbm)
 data(agaricus.train, package = "lightgbm")
 train <- agaricus.train
 dtrain <- lgb.Dataset(train$data, label = train$label)
@@ -64,11 +63,10 @@ valids <- list(test = dtest)
 model <- lgb.train(
   params = params
   , data = dtrain
-  , nrounds = 10L
+  , nrounds = 5L
   , valids = valids
   , min_data = 1L
   , learning_rate = 1.0
-  , early_stopping_rounds = 5L
 )
 preds <- predict(model, test$data)
 }

R-package/man/readRDS.lgb.Booster.Rd

@@ -18,6 +18,7 @@ readRDS.lgb.Booster(file = "", refhook = NULL)
 Attempts to load a model stored in a \code{.rds} file, using \code{\link[base]{readRDS}}
 }
 \examples{
+\donttest{
 library(lightgbm)
 data(agaricus.train, package = "lightgbm")
 train <- agaricus.train
@@ -38,5 +39,5 @@ model <- lgb.train(
 )
 saveRDS.lgb.Booster(model, "model.rds")
 new_model <- readRDS.lgb.Booster("model.rds")
-
+}
 }

R-package/man/saveRDS.lgb.Booster.Rd

@@ -42,6 +42,7 @@ Attempts to save a model using RDS. Has an additional parameter (\code{raw})
              which decides whether to save the raw model or not.
 }
 \examples{
+\donttest{
 library(lightgbm)
 data(agaricus.train, package = "lightgbm")
 train <- agaricus.train
@@ -62,3 +63,4 @@ model <- lgb.train(
 )
 saveRDS.lgb.Booster(model, "model.rds")
 }
+}

R-package/man/setinfo.Rd

@@ -38,7 +38,6 @@ The \code{name} field can be one of the following:
 }
 }
 \examples{
-library(lightgbm)
 data(agaricus.train, package = "lightgbm")
 train <- agaricus.train
 dtrain <- lgb.Dataset(train$data, label = train$label)

R-package/man/slice.Rd

@@ -24,7 +24,6 @@ Get a new \code{lgb.Dataset} containing the specified rows of
              original \code{lgb.Dataset} object
 }
 \examples{
-library(lightgbm)
 data(agaricus.train, package = "lightgbm")
 train <- agaricus.train
 dtrain <- lgb.Dataset(train$data, label = train$label)