Before you can create a model, you need to understand the pieces and parts that form them. Models include a series of connected processes. Each process includes a tool that can be a geoprocessing tool, another model, or a Python script. Each tool has variables that serve as inputs or outputs.
The following diagram shows you two connected processes:
As you can see in the preceding diagram, the model contains two processes built around the Buffer and Union tools. Each of these tools has a number of variables feeding into it. Variables are identified by the blue and green ovals. Notice that the two processes are sharing a variable – Street_Buffer. This variable is an output of the Buffer tool and also an input for the Union tool.
There are three basic types of variables that are included in a model. They are as follows:
- Data variables: These variables are...