To create a calculation

You can use operators and functions to calculate a new value based on existing property values. You can use the resulting value to filter or select data. For example, you can calculate the area of buildings and then select those whose areas are above a certain area value.

The syntax for calculations varies, depending on whether you use operators or functions.

To perform a calculation using an operator

1. Select the command for which you want to create an expression.
2. In the expression area, do one of the following:
   • Enter a property name manually.
   • Click Property. Select the property you want.
3. To insert an operator, do one of the following:
   • Enter an operator for this property manually.
   • Click an operator button.
   • Click Operators. Select the operator you want.
4. Select or enter the value to evaluate.

   For example, if you are multiplying the value of the property, enter the number or insert a property to multiply by.

5. Specify any further conditions for the expression.

   To create a complex property evaluation, insert an AND or OR operator, and then insert another operator/property combination.

   For help with any expression element, see Creating Expressions - Reference.

6. Click OK to apply the expression.

To perform a calculation using a function

1. Select the command for which you want to create an expression.
2. In the expression area, click one of the following and select a function:
   • Math Functions
   • Text Functions
   • Date Functions
3. Click Property and select the property to apply the function to.
   

   This expression is the definition of a calculated property.

   For help with any expression element, see Creating Expressions - Reference.

4. Click OK to apply the expression.

To find area or length

1. Select the command for which you want to create an expression.
2. In the expression area, enter or insert the geometric function (Area2D or Length2D).
3. Insert the property Geometry in parentheses after the function.
   Note: Insert the Geometry from the Geometry Properties list. Do not change it manually or substitute a value for this property.

   For help with any expression element, see Creating Expressions - Reference.

4. Click OK to apply the expression.