Using Formulas For Numerical Parameters - Autodesk 256B1-05A761-1301 - AutoCAD Revit Structure Suite 2010 User Manual

2 Click the dimension.
You may need to zoom in to see the dimension clearly. Revit Architecture displays its value in
a text box.
3 Edit the value, entering the desired formula.
TIP In formulas, keep units consistent. Do not mix units. You can use constants with no units assigned to them.
Valid formula for setting wall length

Using Formulas for Numerical Parameters

Formulas allow you to create parameters that depend on other parameters for their values. A simple example
would be a width parameter set to equal twice the height of an object. In practice, formulas can be used in
many ways, both simple and sophisticated. Typical uses include embedding design relationships, relating a
number of instances to a variable length, and setting up angular relationships. For example, formulas can
be used to
Calculate area or volume of geometry
Create a clearance dimension parameter controlled by element size
Convert continuously variable values into integer values
Resizing Elements with Formulas | 387