Get a Google Map.
get_googlemap queries the Google Maps Static API version 2 to download
a static map. Note that in most cases by using this function you are
agreeing to the Google Maps API Terms of Service at
https://cloud.google.com/maps-platform/terms/. Note that as of
mid-2018, registering with Google Cloud to obtain an API key is required to
use any of Google's services, including get_googlemap. Usage and
billing may apply, see the links under See Also further down in this
documentation for more details.
get_googlemap(center = c(lon = -95.3632715, lat = 29.7632836),
zoom = 10, size = c(640, 640), scale = 2, format = c("png8",
"gif", "jpg", "jpg-baseline", "png32"), maptype = c("terrain",
"satellite", "roadmap", "hybrid"), language = "en-EN",
messaging = FALSE, urlonly = FALSE, filename = NULL,
color = c("color", "bw"), force = FALSE, where = tempdir(),
archiving = FALSE, ext = "com", inject = "", region, markers, path,
visible, style, ...)center |
the center of the map; either a longitude/latitude numeric
vector or a string containing a location, in which case
|
zoom |
map zoom; an integer from 3 (continent) to 21 (building), default value 10 (city) |
size |
rectangular dimensions of map in pixels - horizontal x vertical - with a max of c(640, 640). this parameter is affected in a multiplicative way by scale. |
scale |
multiplicative factor for the number of pixels returned possible values are 1, 2, or 4 (e.g. size = c(640,640) and scale = 2 returns an image with 1280x1280 pixels). 4 is reserved for google business users only. scale also affects the size of labels as well. |
format |
character string providing image format - png, jpeg, and gif formats available in various flavors |
maptype |
character string providing google map theme. options available are "terrain", "satellite", "roadmap", and "hybrid" |
language |
character string providing language of map labels (for themes with them) in the format "en-EN". not all languages are supported; for those which aren't the default language is used |
messaging |
turn messaging on/off |
urlonly |
return url only |
filename |
destination file for download (file extension added according
to format). Default |
color |
color or black-and-white |
force |
if the map is on file, should a new map be looked up? |
where |
where should the file drawer be located (without terminating "/") |
archiving |
use archived maps. note: by changing to TRUE you agree to the one of the approved uses listed in the Google Maps API Terms of Service : http://developers.google.com/maps/terms. |
ext |
domain extension (e.g. "com", "co.nz") |
inject |
character string to add to the url |
region |
borders to display as a region code specified as a two-character ccTLD ("top-level domain") value, see http://en.wikipedia.org/wiki/List_of_Internet_top-level_domains#Country_code_top-level_domains |
markers |
data.frame with first column longitude, second column latitude, for which google markers should be embedded in the map image, or character string to be passed directly to api |
path |
data.frame (or list of data.frames) with first column longitude, second column latitude, for which a single path should be embedded in the map image, or character string to be passed directly to api |
visible |
a location as a longitude/latitude numeric vector (or data frame with first column longitude, second latitude) or vector of character string addresses which should be visible in map extent |
style |
character string to be supplied directly to the api for the style argument or a named vector (see examples). this is a powerful complex specification, see https://developers.google.com/maps/documentation/staticmaps/ |
... |
... |
a ggmap object (a classed raster object with a bounding box attribute)
David Kahle david.kahle@gmail.com
https://developers.google.com/maps/documentation/maps-static/intro,
https://developers.google.com/maps/documentation/maps-static/dev-guide,
https://developers.google.com/maps/documentation/maps-static/get-api-key,
https://developers.google.com/maps/documentation/maps-static/usage-and-billing
ggmap, register_google
## Not run: requires Google API key, see ?register_google
## basic usage
########################################
(map <- get_googlemap(c(-97.14667, 31.5493)))
ggmap(map)
# plotting based on a colloquial name
# this requires a geocode() call, and needs that API
get_googlemap("waco, texas") %>% ggmap()
# different maptypes are available
get_googlemap("waco, texas", maptype = "satellite") %>% ggmap()
get_googlemap("waco, texas", maptype = "hybrid") %>% ggmap()
# you can get the url as follows
# see ?register_google if you want the key printed
get_googlemap(urlonly = TRUE)
## other usage
########################################
# markers and paths are easy to access
d <- function(x=-95.36, y=29.76, n,r,a){
round(data.frame(
lon = jitter(rep(x,n), amount = a),
lat = jitter(rep(y,n), amount = a)
), digits = r)
}
df <- d(n=50,r=3,a=.3)
map <- get_googlemap(markers = df, path = df, scale = 2)
ggmap(map)
ggmap(map, extent = "device") +
geom_point(aes(x = lon, y = lat), data = df, size = 3, colour = "black") +
geom_path(aes(x = lon, y = lat), data = df)
gc <- geocode("waco, texas", source = "google")
center <- as.numeric(gc)
ggmap(get_googlemap(center = center, color = "bw", scale = 2), extent = "device")
# the scale argument can be seen in the following
# (make your graphics device as large as possible)
ggmap(get_googlemap(center, scale = 1), extent = "panel") # pixelated
ggmap(get_googlemap(center, scale = 2), extent = "panel") # fine
# archiving; note that you must meet google's terms for this condition
map <- get_googlemap(archiving = TRUE)
map <- get_googlemap()
map <- get_googlemap()
ggmap(map)
# style
map <- get_googlemap(
maptype = "roadmap",
style = c(feature = "all", element = "labels", visibility = "off"),
color = "bw"
)
ggmap(map)
## End(Not run)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.