One of the things that NX does extremely well is vary your geometry according to all types of numerical inputs. However, in many cases it is important to vary an assembly according to similar numerical inputs. For example, imagine a table assembly with four legs. As the table is lengthened, a new type of leg is needed, located right in the mid-section. The new leg is a different component from the other legs on the ends. In NX8 you are able to set a variable in the expression editor of the assembly master part file that is capable of controlling the suppression state of the mid-section table leg. In order to accomplish this, you must pre assemble the mid-section table leg, or any other component that you want to control, then create an if statement that will control the expression for the suppression state then assign that expression to the component. The result will be a table upon which a mid table leg will appear, when the length is made longer.