leafletR (version 0.2-1)

leaflet: Create a Leaflet web-map

Description

Creates a web-map of users' spatial data over open-source base maps. Output consists of a ready to use HTML file and a GeoJSON data file.

Usage

leaflet(data, dest, title, size, base.map="osm", center, 
  zoom, style, popup, incl.data=FALSE, overwrite=TRUE)
leaf(data, dest, title, size, base.map="osm", center, 
  zoom, style, popup, incl.data=FALSE, overwrite=TRUE)

Arguments

data

Name(s) of data file(s) (GeoJSON format), as string or a list of strings. Plotting order follows the file sequence.

dest

Path to the data file, as string. Optional -- if missing, the current working directory is used.

title

Map title, as string. Default is "map".

size

Size of the map on the website in pixels, as numeric vector -- c(width, height). Optional -- if missing, a fullscreen (browser window) map is generated.

base.map

Base map(s) in the background of the data, as string. One or a list of "osm" (OpenStreetMap standard map), "tls" (Thunderforest Landscape), "mqosm" (MapQuest OSM), "mqsat" (MapQuest Open Aerial), "

center

Map center coordinates in decimal degrees, as vector of two numeric values: c(latitude, longitude). Optional -- if missing, the data layer is centered automatically.

zoom

Map zoom level, as integer value. Usually a value between 0 (global small scale) and 18 (detailed large scale). The MapQuest Open Aerial map (base.map="mqsat") provides only 12 zoom levels [0-11]. Optional -- if miss

style

Style(s) of the data layer(s). One or a list of style object(s), created by styleSingle, styleGrad or styleCat

popup

Properties (attributes) of the data to be shown in a popup when a map object is clicked. String or a vector of strings. "*" adds all available properties to the popup (http://cran.r-project.org/package=RJSONIO{RJSONIO} package re

incl.data

If TRUE, data is included in the HTML file itself. Per default (incl.data=FALSE) the data is saved in a separate file. Including data in the HTML file allows for viewing the map locally on Chrome and Opera browsers.

overwrite

TRUE (which is the default) overwrites existing files with the same name.

Value

• HTML file path, as string.

encoding

UTF-8

References

Base map tiles are provided by lll{ OpenStreetMap standard map http://www.openstreetmap.org Thunderforest Landscape http://www.thunderforest.com MapQuest OSM http://www.mapquest.com MapQuest Open Aerial http://www.mapquest.com Stamen Watercolor http://stamen.com Stamen Toner http://stamen.com }

See Also

styleSingle, styleGrad, styleCat

Examples

# prepare data
data(quakes)
dat <- toGeoJSON(data=quakes, dest=tempdir())

# create map quick and simple
map <- leaflet(dat)
browseURL(map)

# set output directory and map title
map <- leaflet(data=dat, dest=tempdir(), title="Fiji Earthquakes")
browseURL(map)

# set map size, center and zoom level
map <- leaflet(data=dat, dest=tempdir(), 
  size=c(800,600), center=c(-18.35, 179.75), zoom=6)
browseURL(map)

# set base map and popup
# magnitude is used as popup (type names(quakes) for available properties)
map <- leaflet(data=dat, dest=tempdir(), 
  base.map="mqsat", popup="mag")
browseURL(map)

# include data in HTML file
map <- leaflet(dat, incl.data=TRUE)
browseURL(map)

# preserve existing files from overwriting
map <- leaflet(dat, overwrite=FALSE)

# more than one base map
map <- leaflet(data=dat, dest=tempdir(), 
  base.map=list("osm", "mqsat", "tls"))
browseURL(map)

# multiple properties in the popup
map <- leaflet(data=dat, dest=tempdir(), 
  popup=c("mag", "depth"))
browseURL(map)

# all available properties in the popup
map <- leaflet(data=dat, dest=tempdir(), 
  popup="*")
browseURL(map)

# change style
sty <- styleSingle(col="red", fill=NA)
map <- leaflet(data=dat, dest=tempdir(), base.map="mqsat", style=sty)
browseURL(map)

# more than one data set
park <- toGeoJSON(data=system.file(package="leafletR", "files", 
  "park_sk.zip"), dest=tempdir())
peak <- toGeoJSON(system.file(package="leafletR", "files", "peak_sk.kml"), 
  dest=tempdir())
sty.1 <- styleSingle(col="green", fill="green")
sty.2 <- styleSingle(col="brown", fill="brown", rad=3)
map <- leaflet(data=list(park, peak), dest=tempdir(), 
  style=list(sty.1, sty.2), popup=list("*", "Name"))
browseURL(map)

map <- leaflet(data=list(National.Parks=park, Peaks=peak), dest=tempdir(), 
  style=list(sty.1, sty.2), popup=list("*", "Name"))  # names in legend
browseURL(map)