06-prac-01-BluePlaques.Rmd

---
title: "BluePlaques"
author: "yiyan Sun"
date: "2023-11-17"
output: html_document
---
# packages
```{r}
library(spatstat) #spatstat is a package for analyzing spatial point pattern data
library(here)
library(sp)
library(tmap)
library(sf)
library(tidyverse)
library(stringr)
library(geojson)
library(geojsonio)
library(tmaptools)
library(rgeos)
library(maptools)
```

# read data
```{r}
LondonBorough <- st_read("wk1/london_borough/data/statistical-gis-boundaries-london/ESRI/London_Borough_Excluding_MHW.shp")%>% 
  st_transform(., crs = 27700)

# get the location of all Blue Plaques in the City
BluePlaques <- st_read("https://s3.eu-west-2.amazonaws.com/openplaques/open-plaques-london-2018-04-08.geojson") %>% 
  st_transform(., crs = 27700)

BoroughMap <- LondonBorough %>% 
  dplyr::filter(str_detect(GSS_CODE, "E09")) %>% 
  st_transform(., crs = 27700)
```

# extract the borough
```{r}
# select by attribute
Harrow <- BoroughMap %>% 
  dplyr::filter(., NAME=="Harrow") %>% 
  st_transform(., crs = 27700)

# check the shape of harrow borough
tm_shape(Harrow)+
  tm_polygons(col=NA, alpha = 0.5)
```

clip the data to single borough
```{r}
BluePlaquesSub <- BluePlaques[Harrow,]

tmap_mode("plot")
tm_shape(Harrow)+
  tm_polygons(col=NA, alpha = 0.5)+
  tm_shape(BluePlaquesSub)+
  tm_dots(col="red", size = 0.1)

```

set a window at the borough boundary

```{r}
window <- as.owin(Harrow)
plot(window)
```

spatstat <- point pattern(ppp) object

```{r}
# create a sp object
BluePlaquesSub <- as(BluePlaquesSub, "Spatial")

# create a ppp object
BluePlaquesSub.ppp <- ppp(x=BluePlaquesSub@coords[,1],
                          y=BluePlaquesSub@coords[,2],
                          window=window)
```

```{r}
Bl
```