Make map images reproducibly using google maps API in R

data.csv

make_map.r

# Map a Google Map with Satellite Basemap

# Setup ------------------------------------------------------------------------
## Packages
library(dplyr)
library(ggmap)
library(ggplot2)
library(readr)

## Register Google Key
register_google(key = "API-KEY-HERE")

# Data and bounding box --------------------------------------------------------
## Load data
df <- read_csv("~/Desktop/gmap/data.csv")

## Make variables for bounding box
ext <- 2/111 # extend bounding box by roughly 2 kilometers

lon_min <- min(df$longitude) - ext
lon_max <- max(df$longitude) + ext

lat_min <- min(df$latitude) - ext 
lat_max <- max(df$latitude) + ext

# Make map ---------------------------------------------------------------------
## Grab satellite basemap
sat_map <- get_map(location = c(lon_min, lat_min, lon_max, lat_max), 
        maptype = "satellite",
        source = "google")

## Make figure
ggmap(sat_map) +
  geom_point(data = df, 
             aes(x = longitude, y = latitude, color = type),
             size = 3) +
  scale_color_manual(values = c("dodgerblue", "darkorange")) +
  labs(color = "Treatment\nControl",
       title = "Maps are cool") +
  theme_void() +
  theme(plot.title = element_text(face = "bold"))

## Export
ggsave(filename = "~/Desktop/map.png",
       height = 5, 
       width = 5)