afriadmin

african administrative boundaries

To make administrative boundary polygons for Africa easily accessible from R.

A part of the afrimapr project.

In early development, will change, contact Andy South with questions.

There are various sources of sub-national administrative boundaries available on the web, and existing R packages for accessing them.

geoboundaries via rgeoboundaries seems to be the current best source.

gadm.org is comprehensive and easy to access, but seems less up to date and data sourcing, curation and licensing are not as clear.

HDX (Humanitarian Data eXchange), has some more up-to-date boundaries but currently are trickier to reach for all countries in an automated way. HDX developers have told us that should be improved in coming months.

online user interface prototype

https://andysouth.shinyapps.io/afriadmin-compare/

Install afriadmin

Install the development version from GitHub using remotes.

# install.packages("remotes") # if not already installed

remotes::install_github("afrimapr/afriadmin")

First Usage

library(afriadmin)
library(sf)

## single admin levels

# with interactive map, geoboundaries is default datasource but showing here for info
sftgo <- afriadmin("togo", level=2, datasource='geoboundaries')

# static map
sfeth <- afriadmin("ethiopia",level=4, plot='sf')

# comparing boundaries from different sources


# default compares geoboundaries and gadm
compareadmin("togo", level=2, datasource=c('geoboundaries','gadm'))

# option to compare different geobounadaries types
compareadmin("togo", level=2, datasource=c('geoboundaries','geoboundaries'), type=c('sscu','hpscu') )


## multiple admin levels - experimental

# single static map
afplotadmin("malawi")

# facetted using tmap
# returns a single object containing all admin levels
sfall <- alllevels("angola")


# todo move the readme to an Rmd to allow plots

Use cases

A. I'm a developer in country X, I want to know what options I have for obtaining boundary data at different administrative levels for my country.

1. Single country maps. We want to target in-country use. People in Africa making maps of Africa. Maybe there will be a greater utility for tools that make it easy to make maps of a single country rather than of multiple countries ?

2. low resolution boundaries just for display at country level

3. higher resolution boundaries to allow zooming in. (e.g. what detail is needed in a polygon boundary file to be able to create zonal statistics for a raster file of a given cell size ?)