geom_hex question

gistfile1.txt

# 4ijn-s7e5 is food inspections in Chicago data set 2010 to present
# may take a minute or two...
df <- read.csv("http://data.cityofchicago.org/views/4ijn-s7e5/rows.csv",
               stringsAsFactors = F) 
names(df) <- tolower(names(df))

# we don't want missing values in lat or lon
df <- subset(df, !is.na(longitude) & !is.na(latitude))

# let's look at complaints / food poisonings...
df <- subset(df, inspection.type %in% c("Complaint", "Short Form Complaint", "Suspected Food Poisoning"))

# business licenses 2006 to present... r5kz-chrr
# may take a minute or two...
lic <- read.csv("http://data.cityofchicago.org/views/r5kz-chrr/rows.csv",
               stringsAsFactors = F)
names(lic) <- tolower(names(lic))
lic <- subset(lic, license.description=="Retail Food Establishment")
# get rid of duplicate addresses
lic <- subset(lic, !duplicated(address))

ggplot(df) + geom_hex(aes(x=longitude, y=latitude), bins=30) + scale_fill_gradient(low="black", high="blue")