svamap - leaflet maps from R datasets

The design of this package is that you read in your data to R and produce a spatial dataset of that. The example dataset is a .csv file in the inst folder that you can read in using read_point_data().

Next you export the data to geojson and write it to a .js file that is then submitted to a leaflet webpage.

Two examples are given:

First a map with just a polygon layer that summarises the count of the number of points in a polygon and binds it to a popup.

library(svamap)
##Get the polygon data
data(NUTS_20M)
##Get the point data
pts <- read_point_data()
## Match the location of the points to the polygons and add a count variable to the polygon dataset
polys <- svamap::match_to_county(pts, NUTS_20M, "NUTS_ID")
## Write out the data to a geojson
path_to_data <- write_data(polys)
## Add the data to the leaflet webpage, in this case template "map"
svamap::write_page(path_to_data, template = "map", overwrite = TRUE, browse = TRUE)

A Second map with both a point and polygon layer. Notice the you submit the multiple layers as a list to the write_data() function

library(svamap)
##Get the polygon data
data(NUTS_20M)
##Get the point data
pts <- read_point_data()
## Remove the information from the points that you don't want to display
pts@data <- data.frame(pts@data$Djurslag, stringsAsFactors = FALSE)
## Match points to polygon
polys <- svamap::match_to_county(pts, NUTS_20M, "NUTS_ID")
## Write to geojson
path_to_data <- write_data(list(polys, pts))
## add the data to "map2" template in the package
svamap::write_page(path_to_data, path = "/tmp", template = "map2", overwrite = TRUE, browse = FALSE)

Design

You might wonder why I am not using the Rleaflet library or similar for this. It is about flexibility of designing the map in only html and javascript and the only thing R does is format the data. The down side is the you need to understand R, javascript and html to produce a map.