README.rmd

---
title: "README.rmd"
author: "Ken Steif"
date: "11/11/2020"
output: 
  html_document:
    keep_md: true
    preserve_yaml: false
---
    
# Virginia Beach, Virginia EMS calls w/ geographic coordinates

This repo houses a now deprecated version of the [Virginia Beach EMS calls data](https://data.vbgov.com/dataset/ems-calls-for-service/resource/3e03dc00-a196-48ec-af62-0eaf028f5c27?inner_span=True) with XY coordinates. 

Data from January, 2017 through February, 2018 are included. This dataset is used for a final project option in my course. 

```{r 1_setup, echo = FALSE, include=FALSE}
knitr::opts_chunk$set(echo = FALSE,results=TRUE, message = FALSE, warning=FALSE, 
                      fig.align="center", cache=TRUE)
```

```{r}
library(sf)
library(tidyverse)
library(lubridate)
library(viridis)

source("https://raw.githubusercontent.com/urbanSpatial/Public-Policy-Analytics-Landing/master/functions.r")

```

```{r, cache=TRUE, results=FALSE}
dat <- 
  read.csv("https://raw.githubusercontent.com/urbanSpatial/VaBeachEMSData/main/VaBeach_EMS_with_coords_17_18.csv")

boundary <- 
  st_read("https://opendata.arcgis.com/datasets/82ada480c5344220b2788154955ce5f0_1.geojson") %>%
  filter(!ZIP_CODE %in% c(23456,23457,27950,27927)) %>%
  st_union() %>% st_sf()
```

```{r}
dat <- 
  dat %>% 
    filter(!is.na(X) & !is.na(Y)) %>% 
    st_as_sf(coords = c("X", "Y"), crs = 4326, agr = "constant") %>%
    mutate(callDate = mdy_hm(CallDateandTime),
           hour = hour(callDate)) %>%
    .[boundary,]
```

```{r}
vaFishnet <- st_make_grid(boundary, .007) %>% st_sf() %>% rownames_to_column("id")

jawn <- 
  st_join(dat, vaFishnet) %>%
  st_drop_geometry() %>%
  group_by(id, hour) %>%
  summarize(Count = n()) %>%
    full_join(vaFishnet) %>%
    spread(hour, Count, fill=0) %>%
    st_sf() %>%
    dplyr::select(-`<NA>`)
```
<br>
```{r, fig.width=10, fig.height=12}
gather(jawn, hour, Count, -geometry, -id) %>%
  mutate(hour = fct_relevel(hour, as.character(0:23))) %>%
  mutate(Count2 = case_when(Count == 0 ~ "0",
                              Count == 1 ~ "1",
                              Count >= 2 & Count <= 4 ~ "2-4",
                              Count >= 5 & Count <= 10 ~ "5-10",
                              TRUE ~ ">10")) %>%
  mutate(Count2 = fct_relevel(Count2,"0","1","2-4","5-10",">10")) %>%
    ggplot() +
    geom_sf(aes(fill=Count2), colour=NA) + 
    facet_wrap(~hour, ncol = 4) +
    scale_fill_viridis(discrete=T, name="Count") +
    labs(title="EMS Calls by hour, Virginia Beach") +
    mapTheme()
```