Data Management Capabilities > Managing Part Structures > Windchill Options and Variants Capabilities > Developing Advanced Selection Logic for Configurable Modules > Basic Steps for Defining Advanced Selection > Adding a Constraint > Case Table Editor > Editing a Parameter Formula
  
Editing a Parameter Formula
Using a formula in a case table you can derive the permissible values for a parameter. This provides the ability to determine values based on other information. A formula can be simple or complex, utilizing nesting of other formula or other case table parameters within the calculations.
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To enter and display the formulae and advanced logic expressions in a format that is consistent with Microsoft Excel, set the ato.expression.rendering.context=com.ptc.wpcfg.logic.XLSExpressionRenderingContext property in the WT_HOME/codebase/wt.properties file.
The ability to designate a parameter for allowing formula is available only when the Enable Advanced Case Tables preference is enabled. For more information, see Selecting Case Table Parameters.
1. Specify the formula in the text entry area.
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To define the formula, use the actions located above the text entry area. The Validate action provides the syntax validation feedback without saving the formula.
2. Click OK to save the formula for the permissible parameter value.
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Clicking OK also validates the syntax and saves the well-formed formula.
For more information on the use of formulas, see Using Numeric Operators and Functions in Advanced Logic.