ArcGIS for Desktop

  • Documentation
  • Pricing
  • Support

  • My Profile
  • Help
  • Sign Out
ArcGIS for Desktop

ArcGIS Online

The mapping platform for your organization

ArcGIS for Desktop

A complete professional GIS

ArcGIS for Server

GIS in your enterprise

ArcGIS for Developers

Tools to build location-aware apps

ArcGIS Solutions

Free template maps and apps for your industry

ArcGIS Marketplace

Get apps and data for your organization

  • Documentation
  • Pricing
  • Support
Esri
  • Sign In
user
  • My Profile
  • Sign Out

Help

  • Home
  • Get Started
  • Map
  • Analyze
  • Manage Data
  • Tools
  • More...

Model elements

Model elements are the basic building blocks of models. There are three types:

  • Tools: Geoprocessing tools are the basic building blocks of workflows in a model. Tools perform various operations on geographic or tabular data. When tools are added to a model, they become model elements.
  • Variables: Variables are elements in a model that hold a value or a reference to data stored on disk. There are two types of variables:
    • Data: Data variables are model elements that contain descriptive information about data stored on disk. Properties of data that are described in a data variable include field information, spatial reference, and path.
    • Values: Value variables are values such as strings, numbers, Booleans (true/false values), spatial references, linear units, or extents. Value variables contain anything but references to data stored on disk.
  • Connectors: Connectors connect data and values to tools. The connector arrows show the direction of processing. There are four types of connectors:
    • Data: Data connectors connect data and value variables to tools.
    • Environment: Environment connectors connect a variable containing an environment setting (data or value) to a tool. When the tool is executed, it will use the environment setting.
    • Precondition: Precondition connectors connect a variable to a tool. The tool will execute only after the contents of the precondition variable are created.
    • Feedback: Feedback connectors connect the output of a tool back into the same tool as input.

The diagram below shows how model elements are classified in ModelBuilder:

Model elements

ElementImageDescription

Data variable

Input data

Existing data added to a model. Typically, data variables are the result of specifying a tool's input parameter. This existing data is sometimes referred to as project data.

Derived or output data variable

Derived data

Derived or output data is new data created by a tool in the model. When a tool is added to a model, a variable for the tool's derived data is automatically created and connected to the tool.

New derived data

The tool creates a new dataset that is written to disk when the model is executed.

In/Out derived data

The tool alters the input data when the model is executed. By default, the in/out derived data variable will have the same name as the input data but with a unique number appended at the end.

Value variable

Input value

Values that are input to a tool.

Value variable

Derived value

Values that are the result of a tool. Derived values can be inputs to other tools. The Calculate Value tool, for example, outputs the result of a logical or mathematical calculation.

Tool

System tool

Built-in tool. These tools are built using ArcObjects and a compiled programming language like .NET. Built-in tools are typically system tools (those installed with ArcGIS)

Iterator

Iterators are tools that repeat the same operation or loop through a set of input data or values. Iterators work only within ModelBuilder, not in scripting.

Learn more about iterators in ModelBuilder

Model Only tool

Model only tools functionally enhance ModelBuilder and only work within ModelBuilder, not in scripting.

Learn more about Model Only tools

Stop Model Only tool

The tool with this symbology is the Stop (Model Only) tool. This tool is only different than other Model Only tools in symbology in the model (looks like a red stop sign).

Tool

Script tool

Script tool. These tools are created using the Script tool wizard and they run a script file on disk, such as a Python file (.py), AML file (.aml), or executable (.exe or .bat).

Tool

Model tool

Model tool. A model is a collection of many tools connected together representing a workflow. A model tool can be run from its tool dialog box or added and used in another model or a script.

Description of model elements

Related Topics

  • A quick tour of ModelBuilder
  • Tool types
  • A quick tour of managing model environments
  • Setting preconditions
  • Using feedback in iteration
Feedback on this topic?

ArcGIS for Desktop

  • Home
  • Documentation
  • Pricing
  • Support

ArcGIS Platform

  • ArcGIS Online
  • ArcGIS for Desktop
  • ArcGIS for Server
  • ArcGIS for Developers
  • ArcGIS Solutions
  • ArcGIS Marketplace

About Esri

  • About Us
  • Careers
  • Insiders Blog
  • User Conference
  • Developer Summit
Esri
© Copyright 2016 Environmental Systems Research Institute, Inc. | Privacy | Legal