Adjust size of leaflet map in rmarkdown html

Question

I'd like to change the height and width of leaflet map outputs in html document. Is there a simple way to do this in R markdown without getting into whole CSS business?

```{r}
library(leaflet)
library(dplyr)

m <- leaflet() %>% setView(lng = -71.0589, lat = 42.3601, zoom = 12)
m %>% addTiles() 
```

Ideally, I want the width of map to be the same width of code block as shown below.

Answer 1

I found that changing fig.width and fig.height did not change the size of my leaflet maps. However, changing a different parameter/option did.

Try changing the width/height using this in the header for the code chunk:

{r, width = 40, height = 30}

Or alternatively, another thing that has worked for me is to use this (in this case, do not put anything in the chunk header:

m <- leaflet(width = "100%") %>%

Answer 2

This works fine:

SomeData %>% 
  leaflet(height=2000, width=2000) %>% 
  addTiles() %>% 
  addMarkers(clusterOption=markerClusterOptions())

Here SomeData is a dataframe containing columns: Lat and Long.