A tool can be placed anywhere in the expression, but it should be placed in a position that produces valid Map Algebra syntax. The remaining input required by the tool must then be entered. By clicking a tool in the list, the tool name and open and close parentheses will be placed in the expression where the pointer is currently positioned.

The tool list is a convenient selection of tools that can be used in the Map Algebra expression. Take care to ensure that the expression follows the rules for correct Map Algebra syntax rules. By clicking any of these buttons, that number or operator will be entered into the expression where the pointer is currently positioned. The operator buttons allow you to enter mathematical (addition, division, and so on) and logical (greater than, equal to, and so forth) operators into the expression. The calculator buttons allow you to enter numeric values into the expression.

When the tool is used in ModelBuilder, the list will contain the layers in the table of contents, outputs created in the model, and other model variables. If you are using the tool standing alone, the list will contain the layers in the table of contents. The input Layers and variables list identifies the input that can be used in the Map Algebra expression.

Raster Calculator tool dialog box example Layers and variables There are four main areas in the tool dialog box that are used to create a Map Algebra expression: When multiple tools or operators are used in one expression, the performance of this equation will generally be faster than executing each of the operators or tools individually. Raster Calculator is designed to execute a single-line algebraic expression using multiple tools and operators using a simple, calculator-like tool interface.

Use multiple Spatial Analyst tools in a single expression.

Apply Spatial Analyst operators on three or more inputs in a single expression.

Support the use of variables in Map Algebra when in ModelBuilder.

Implement single-line algebraic expressions.

The Raster Calculator tool is specifically designed to offer the following benefits: To learn more about scripting and Map Algebra, see the help topic What is Map Algebra? The Raster Calculator tool is not intended to be used in scripting environments and is not available in the standard Spatial Analyst ArcPy module.

Arcmap raster calculator