sf crime map

library(ggmap)
library(readr)

data <- read_csv("./input/train.csv")

locations = c(left = -122.5222, 
              bottom = 37.7073, 
              right = -122.3481,
              top = 37.8381)

map <-get_map(location = locations, zoom = 12, source = "osm", color="bw")  

data1 <- data[data$Category == c("ASSAULT", "NON-CRIMINAL", "WEAPON LAWS",
                                 "OTHER OFFENSES", "WARRANTS", "LARCENY/THEFT"),]

p <- ggmap(map) + stat_density2d(aes(x = X, y = Y, fill = ..level.., alpha = ..level..),
                                 bins = 15, geom = "polygon", data = data1) +
  scale_fill_gradient(low = "green", high = "red", name = "Crime\nDensity\nLevels") +
  scale_alpha(range = c(0.25, 0.75), guide = FALSE)  +
  facet_wrap(~Category, ncol =3) + ggtitle("San Francisco Crimes Heatmap by Category")                                                                                             

#Save
ggsave("Heatmap_Crimes.png", p, width=14, height=10, units="in")