Map Algebra and Model Building
In This Chapter
Using cartographic modeling
Getting the hang of map algebra
Understanding the map algebra language and functions
Creating a model
Going live with your model
Testing to make sure that your model makes sense
If you started reading this book here, you’re anxious to get started making the GIS work for you. Although retrieving maps and doing all the individual analyses are often enough for everyday tasks, every now and then, you want to watch the GIS spread its wings and do something really spectacular. This chapter explains how you can let your GIS really soar.
In this chapter, I use the raster model to demonstrate how cartographic modeling works. I also show you the basics of the cartographic modeling language called map algebra, the functions that the language provides, and how map algebra creates powerful models. Finally, I show you how you can test the output from map analysis for accuracy and acceptability.
Creating Cartographic Models
When C. Dana Tomlin developed his original Map Analysis Package (MAP) for his dissertation, he wasn’t thinking ...