How to plot a decision tree horizontally in R Markdown?

Question

In R Markdown, I would like to plot a decision tree horizontally, so that it fits better the entire PDF page. This code plots it vertically:

```{r, message=FALSE, warning = FALSE, echo=FALSE, cache = FALSE}

rpart.lrn <- makeLearner("classif.rpart", predict.type = "prob", fix.factors.prediction = FALSE) 
model = train(rpart.lrn, task = classif.task, subset = train.set)
tree <- getLearnerModel(model)
rpart.plot(tree) # visualise the tree
```

How can I plot it horizontally instead?

Answer 1

Have you tried so set fig.height and fig.width, for example {r ggpair, echo=FALSE, message = FALSE, warning = FALSE, fig.height = 12, fig.width = 12}