added political boundaries

adjusted data dir
added steps and example to readme

01_download_data.R

@@ -3,7 +3,7 @@ library(nhdplusTools)
 library(sf)
 
 # set data dir
-nhdplusTools_data_dir(dir = "data")
+nhdplusTools_data_dir(dir = "data/hydrologic")
 
 # load extent of map
 extent <- read.csv(file = "extent.csv")

02_process_data.R

@@ -1,9 +1,16 @@
 # load libraries
 library(sf)
 
-# load and crop data
+# load and crop hydrologic data
 data <- list(NULL)
 sf_use_s2(FALSE)
 for (layer in layers){
   data[[layer]] <- st_crop(st_read(paste0(nhdplusTools_data_dir(),"/data.gpkg"), layer = layer), y = extent_bbox)
 }
+
+# load political boundaries
+political <- list(NULL)
+political_boundaries <- list.files(path = "data/political_boundaries")
+for (boundary in political_boundaries) {
+  political[[boundary]] <- st_read(paste0("data/political_boundaries/", boundary))
+}

03_make_figures.R

@@ -42,6 +42,5 @@ plot(sf::st_geometry(data$NHDFlowline),
      xlim = c(extent$longitude_min, extent$longitude_max),
      ylim = c(extent$latitude_min, extent$latitude_max),
      add = TRUE)
-
 # finish saving figure
 dev.off()

README.md

@@ -1,3 +1,11 @@
 # pretty_rivers
 
 Downloads USGS data for a given location and makes a pretty map of the rivers. The width of the rivers is proportional to the area of land that the section of river drains.
+
+## To run :
+1. Clone the repository
+2. Edit the extent of the map you want to produce in `extent.csv`. Include lat/long coordinates of two opposite corners (i.e. top-left and bottom-right).
+3. Run the scripts. Downloading the data and loading the data will take the longest. The whole of Wisconsin downloads ~12GB of data
+
+## Example figure
+![example figure](figures/map.tiff)