Creating a Formula  

This task explains how to create a formula specifying that the external radius of a hollow cylinder is twice its internal diameter. Note that the radius of a sketch can be defined by a formula provided it is declared as a constraint.
  • A formula is a statement that you can write by selecting items from the editor dictionary list. For more information about the language to be used, see Knowledge Advisor User's Guide: Knowledgeware Language.
  • The period is generally used as a separator between the whole numbers and the fractional part of a number. Using a comma as a separator in place of the period is not recommended in real values intended to be used directly in relations.
    Example: Real1 = 2,1 + 5,4 is not allowed whereas Real1 = Real2 + Real3 is allowed regardless of the separator used when valuating Real2 and Real3.
Make sure Relations is active in the Tools>Options...>Infrastructure>Part Infrastructure>Display tab.

  1. Open the KwrStartDocument.CATPart document.

  2. Click the  icon to display the f(x) dialog box. Make sure that you have not clicked Incremental ().

    Method 1 

    • Double-click the PartBody\Sketch.1\Radius.3\Radius parameter from the parameter list. The Formula Editor is displayed.

    • Enter the PartBody\Hole.1\HoleLimit.1\Depth*2 relation in the formula field.  Go to Tips and Techniques for information on how to manipulate parameters and formulas.

    • Click OK in the Formula Editor.

    Method 2

    • Select the PartBody\Sketch.1\Radius.1\Radius from the parameter list.

    • Click Add Formula. The Formula Editor is displayed.

    • Enter the PartBody\Hole.1\HoleLimit.1\Depth*2 relation in the formula field. Go to  Tips and Techniques  for information on how to manipulate parameters and formulas.

    • Click OK in the Formulas Editor.

  3. Click Apply to update the document.

  4. Click OK to close the dialog box.