In thk686/keitt.ssi.2019: Learning materials for Geospatial Data Analysis in R, part of the UT Summer Statistics Institute

This is an example of plotting data from TXPWD. The Gould Eco Regions data can be found here.

Load sf.

library(tidyverse)
library(sf)

Read in the shapefile.

ger <- st_read("GouldEcoRegions.shp") %>% st_simplify(dTolerance = 1e3)

Print summary of the columns.

summary(ger)

Look the Coordinate Reference System. Its the Texas State Mapping System.

st_crs(ger)

We can plot using the sf plot function.

if (compareVersion(as.character(packageVersion("ggplot2")), "2.2.1") < 1)
  devtools::install_github("hadley/ggplot2")
library(ggplot2)

ggplot() +
  geom_sf(data = ger, aes(fill = Shape_Area)) -> er.plot
er.plot

er.plot + geom_sf(data = st_centroid(ger), color = "red")

Read in park boundaries

parks <- st_read("TPWDStateParksBoundary.shp") %>% st_simplify(dTolerance = 1e3)

With buffering and alpha, we can create a halo around parks to make small polygons more visible.

er.plot +
  geom_sf(data = st_buffer(parks, 2e4), color = NA, fill = "darkred", alpha = 0.25) +
  geom_sf(data = parks, color = "red", fill = NA)

thk686/keitt.ssi.2019 documentation built on June 28, 2019, 1:28 p.m.