lsoaExample.Rmd

---
title: "LSOA mapping (Solent)"
author: "Thomas W Rushby"
date: "24/06/2021"
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)

library(sf)          # classes and functions for vector data
library(ggplot2)
library(tidyverse)
```

## Geography

```{r loadGeog}

inf <- here::here("data", "boundaries", "lsoa_solent.shp") # use here to specify the data location
message("Loading LSOA geometry from file")

sf_data <- sf::read_sf(inf)

head(sf_data)

```

Draw the map using leaflet ([useful resource](https://rstudio.github.io/leaflet/)) ...

```{r}
# Useful lookup spatial reference for CRS
# https://spatialreference.org/ref/epsg/27700/
st_coord_sys <- st_crs(sf_data) # check coord system
st_coord_sys # current coord system EPSG: 4326 (is what leaflet wants - good)

# transform the coord system if required
if(st_coord_sys$epsg != 4326){
  sf_data <- st_transform(sf_data, "+proj=longlat +datum=WGS84")
}

# Create map (using leaflet) ----

# create popup first (using htmltools)
# by adding a column to sf_data object
library(htmltools)
sf_data$popup_text <-
  paste("LSOA code: ","<b>", sf_data$LSOA11CD, "</b>",
        '<br/>', 'LSOA: ', '<b>', sf_data$LSOA11NM, '</b>', ' ') %>%
  lapply(htmltools::HTML)

# plot map
library(leaflet)
leaflet(sf_data %>% filter(LAD11NM == "Southampton")) %>%
  addTiles() %>%  # Add default OpenStreetMap map tiles
  addPolygons(color = "blue", fillColor = "blue", fillOpacity = 0.2, weight = 1.5, popup = ~(LSOA11NM), # popups clicked
              label = ~(popup_text),                                            # define labels
              labelOptions = labelOptions(                                      # label options
                style = list("font-weight" = "normal", padding = "2px 2px"),
                direction = "auto"),
              highlight = highlightOptions(
                weight = 5,
                color = "#666",
                fillOpacity = 0.7,
                bringToFront = TRUE))
```


## Demand model

Start with current electricity demand ... we have stats for LSOAs from 2019:

```{r loadLSOAdata}
# electricity consumption data at MSOA level (pre downloaded)
inFile <- here::here("data", "energy", "LSOA_Dom_Elec", "LSOA_ELEC_2019.csv")

# fix inFile - use path to file ...
inFile <- "/Users/twr1m15/SotonGitLab/Personal/mapping-with-r/data/energy/LSOA_Dom_Elec/LSOA_ELEC_2019.csv"

lsoa_elecData <- readr::read_csv(inFile)
head(lsoa_elecData)
```

Join to geography data ...

```{r}
sf_data_elec <- left_join(sf_data,lsoa_elecData, by = c("LSOA11CD" = "Lower Layer Super Output Area (LSOA) Code"))
```

And re-draw the map ...

```{r}
# create popup first (using htmltools)
sf_data_elec$popup_text <-
  paste("LSOA code: ","<b>", sf_data_elec$LSOA11CD, "</b>",
        '<br/>', 'LSOA: ', '<b>', sf_data_elec$LSOA11NM, '</b>', 
        '<br/>', 'kWh/meter (median): ', '<b>', round(sf_data_elec$`Median domestic electricity consumption \n(kWh per meter)`,0), '</b>', 'kWh') %>%
  lapply(htmltools::HTML)

# plot map
qpal <- colorQuantile("Reds", sf_data_elec$`Median domestic electricity consumption \n(kWh per meter)`, n = 9)

leaflet(sf_data_elec %>% filter(LAD11NM == "Southampton")) %>%
  addTiles() %>%  # Add default OpenStreetMap map tiles
  addPolygons(color = ~qpal(`Median domestic electricity consumption \n(kWh per meter)`),  fillOpacity = 0.7, weight = 1.5, popup = ~(LSOA11NM), # popups clicked
              label = ~(popup_text),                                            # define labels
              labelOptions = labelOptions(                                      # label options
                style = list("font-weight" = "normal", padding = "2px 2px"),
                direction = "auto"),
              highlight = highlightOptions(
                weight = 3,
                color = "Red",
                fillOpacity = 1,
                bringToFront = TRUE))
```