Chapter 3. Common Data Preprocessing Steps
In this chapter, we will cover the following recipes:
- Converting points to lines to polygons and back – QGIS
- Converting points to lines to polygons and back – SpatiaLite
- Converting points to lines to polygons and back – PostGIS
- Cropping rasters
- Clipping vectors
- Extracting vectors
- Converting rasters to vectors
- Converting vectors to rasters
- Building DateTime strings
- Geotagging photos
Introduction
When working with other people's data, it is often not the exact format that you need for a particular use. This chapter is all about taking the data that you do have and converting it to what you actually need. It covers converting between different types of vectors (points, lines, and polygons), between vectors and polygons, and cutting out only the parts that you need. Taking data from how you get it and converting it to the format and layout that you need in order to work with is often called 'data preprocessing'.
