Car crashes in Nashville by Hour and Day

### Construct a map of traffic accident date vs time similar to:
### https://www.reddit.com/r/dataisbeautiful/comments/i0a91n/car_crashes_by_time_and_day_chicago_oc/
### Data Source:  https://data.nashville.gov/browse?category=Public%20Safety

library(tidyverse)
library(janitor)
library(lubridate)

data <-
  "Nashville/Traffic_Accidents/Traffic_Accidents__2020_.csv" %>%
  read_csv() %>%
  janitor::clean_names()
  select(date_and_time) %>%
  filter(!is.na(date_and_time)) %>%
  mutate(date_and_time = mdy_hms(date_and_time)) %>%
  mutate(hour   = hour(date_and_time)) %>%
  mutate(dow    = wday(date_and_time)) %>%
  group_by(hour, dow) %>%
  summarize(wrecks = n())

g_wrecks_hour_dow <-
  ggplot(data = data, aes(x = hour, y = dow, fill = wrecks)) +
  theme_minimal() +
  theme(legend.position = "none") +
  theme(plot.title = element_text(hjust = 0.5)) +
  theme(plot.subtitle = element_text(hjust = 0.5)) +
  theme(plot.caption = element_text(hjust = 0.5)) +
  geom_tile(color = "white") +

  labs(title = "Car Crashes by Time of Week in Nashville",
       subtitle = "Relative Frequency of Reported Crashes by Day, Hour",
       caption = paste("Data source:  https://data.nashville.gov/browse?category=Public%20Safety\n",
                       "Inspired by:   https://www.reddit.com/r/dataisbeautiful/comments/i0a91n/car_crashes_by_time_and_day_chicago_oc/",
                       sep = ""),
       x = "", y = "") +

  scale_fill_gradient(low = "white", high = "darkred") +

  scale_y_continuous(trans = "reverse",
                     breaks = c(1, 2, 3, 4, 5, 6, 7),
                     labels = c("Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday")) +

  scale_x_continuous(breaks = c(0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22),
                     labels = c("12 am", "2 am", "4 am", "6 am", "8 am", "10 am", "12 pm", "2 pm ", "4 pm", "6 pm", "8 pm", "10 pm"))

print(g_wrecks_hour_dow)