The ArcGIS software that you use in this course contains hundreds of tools that you can use to manipulate and analyze GIS data. Back before ArcGIS had a graphical user interface (GUI), people would access these tools by typing commands. Nowadays, you can point and click your way through a whole hierarchy of toolboxes using the Catalog window in ArcGIS Pro.
Although you may have seen them before, let’s take a quick look at the toolboxes:
- Open a new or existing project in ArcGIS Pro.
- If the Geoprocessing pane isn't visible, click the Analysis tab, then click Tools.
- In the Geoprocessing pane, click the Toolboxes tab heading. Notice that the tools are organized into toolboxes and toolsets. For example, the IDW and Spline tools can be found in the Interpolation toolset within the Spatial Analyst toolbox. Sometimes it’s faster to use the Find Tools box at the top of the Geoprocessing tab to find the tool you need instead of browsing this tree.
Let’s examine a tool. Expand Analysis Tools > Proximity > Buffer, and double-click the Buffer tool to open it.
You've probably seen this tool in past courses, but this time, really pay attention to the components that make up the user interface. Specifically, you’re looking at a dialog with many fields. Each geoprocessing tool has required inputs and outputs. Those are indicated by the red asterisks. They represent the minimum amount of information you need to supply in order to run a tool. For the Buffer tool, you’re required to supply an input features location (the features that will be buffered) and a buffer distance. You’re also required to indicate an output feature class location (for the new buffered features).
Many tools also have optional parameters. You can modify these if you want, but if you don’t supply them, the tool will still run using default values. For the Buffer tool, optional parameters are the Side Type, End Type, Method, and Dissolve Type. Optional parameters are typically specified after required parameters.
Hover your mouse over any of the tool parameters. You should see a blue "info" icon to the left of the parameter. Moving your mouse over that icon will show a brief description of the parameter in a pop-out window.
If you’re not sure what a parameter means, this is a good way to learn. For example, viewing the pop-out documentation for the End Type parameter will show you an explanation of what this parameter means and list the two options: Round and Flat.
If you need even more help, each tool is more expansively documented in the ArcGIS Pro web-based help system. You can access a tool's documentation in this system by clicking on the blue ? icon in the upper-right of the tool dialog, which will open the help page in your default web browser.
- Open the web-based help page for the Buffer tool. As mentioned, the help page will provide extensive documentation of the tool's usage. In the upper right of the help page, you should see a list of links that are shortcuts to various sections of the tool's documentation.
- Click the Parameters link to jump to that section. There you should find that the information is divided between two tabs (Dialog and Python), with the Dialog tab displayed by default. The Dialog tab focuses on providing help to those who are executing the tool through the ArcGIS Pro GUI, while the Python tab focuses on providing help to those who are invoking it through a Python script.
- Click on the Python tab, since that's our focus in this class. You should see the name, a description, and the data type associated with each of the tool's parameters. That information is certainly helpful, but often even more helpful is the Code sample section that appears below the parameter list. Every tool's help page has these programming examples showing ways to run the tool from within a script, and they will be extremely valuable to you as you complete the assignments in this course.