Book Image

Learning Geospatial Analysis with Python - Third Edition

By : Joel Lawhead
Book Image

Learning Geospatial Analysis with Python - Third Edition

By: Joel Lawhead

Overview of this book

Geospatial analysis is used in almost every domain you can think of, including defense, farming, and even medicine. With this systematic guide, you'll get started with geographic information system (GIS) and remote sensing analysis using the latest features in Python. This book will take you through GIS techniques, geodatabases, geospatial raster data, and much more using the latest built-in tools and libraries in Python 3.7. You'll learn everything you need to know about using software packages or APIs and generic algorithms that can be used for different situations. Furthermore, you'll learn how to apply simple Python GIS geospatial processes to a variety of problems, and work with remote sensing data. By the end of the book, you'll be able to build a generic corporate system, which can be implemented in any organization to manage customer support requests and field support personnel.
Table of Contents (15 chapters)
Free Chapter
1
Section 1: The History and the Present of the Industry
5
Section 2: Geospatial Analysis Concepts
10
Section 3: Practical Geospatial Processing Techniques

Creating histograms

A histogram shows the statistical frequency of data distribution within a dataset. In the case of remote sensing, the dataset is an image. The data distribution is the frequency of pixels in the range of 0 to 255, which is the range of 8-byte numbers that are used to store image information on computers.

In an RGB image, color is represented as a 3-digit tuple with (0,0,0, 0, 0) being black and (255,255,255) being white. We can graph the histogram of an image with the frequency of each value along the y-axis and the range of 256 possible pixel values along the x-axis.

Remember in Chapter 1, Learning about Geospatial Analysis with Python, in the Creating the simplest possible Python GIS section, when we used the Turtle graphics engine included with Python to create a simple GIS? Well, we can also use it to easily graph histograms.

Histograms are usually a one...