L19: Combining Vectors and Rasters

Grids, Zonal Stats, Count by Polygons

Bogdan G. Popescu
bogdan.popescu@johncabot.edu

John Cabot University

Introduction

In this lecture, we will continue to learn about spatial operations

  1. Making grids
  1. Calculating zonal statistics
  1. Calculating number of points within a polygon
  1. Learning more about extracting Open Street Map data

We will use all these tools to make informed business decisisons

Overview

We will use some of the GIS operations that we learned. We will go over one practical example.

Let’s assume McDonald’s tries to open new restaurants in Rome Italy.

Like all profit-oriented companies, McDonald’s tries to minimize costs and maximize profit.

They are trying to open restaurants in areas:

  • where there isn’t too much competition
  • where many people live

The Problem

Thus, as the good consultant that you are, you will use three data sources:

  • No. of restaurants and their location in Rome
  • No. of already-existing McDonald’s restaurants
  • Population density in Rome

We will then perform GIS operations and make business recommendations.

The Data

  • The Restaurant Data
  • Open Street Map is a great data source
  • However, downloading the entire area can be difficult
  • This helps download only specific items from OSM: this is especially helpful for downloading points

The Data: Overpass-turbo.eu

This is what https:/overpass-turbo.eu/ looks like (2023/11/20).

The Data: Restaurants

We first zoom into the relevant area.