Adding Variables

Define variables to create a parametric model.

A model is parametric when it is created using variable expressions. When a variable expression is modified, any items dependent on that variable are re-evaluated and automatically updated. It is the recommended construction method when creating a model, but not compulsory.

Defined variables are stored as part of the model in the .cfx file.

  1. Open the Create Variable dialog using one of the following workflows:
    • On the Construct tab, in the Define group, click the  Add Variable icon.
    • On the model tree, a right-click context menu is available on Variables. From the list, select Add Variable.
      Figure 1. The model tree (Construction tab).


    • On the model tree, click the icon. From the drop-down list, select Add Variable.
      Figure 2. The drop-down list available in the model tree.


    • Press # to use the keyboard shortcut.
  2. Create the following variables:
    Name Expression Unit
    patch_size 18.8 mm
    chamfer_d 4.3 mm
    feed_pos -6.4 mm
    substrate_w 45 mm
    substrate_d 45 mm
    substrate_h 5 mm
    ceramic_epsR 5.6
    ceramic_tanD 0.0041
    Figure 3. The Create Variable dialog.


    Tip:
    • Click Add to keep the Create Variable dialog open and add more variables.
    • Click Create to add a variable and close the Create Variable dialog.
  3. [Optional] Group the variables related to the patch.
    1. In the model tree, under Variables, select patch_size and chamfer_d.
      Tip: To select multiple objects, press and hold Ctrl while you click the items.
    2. From the right-click context menu, select Group > Create.
    3. Select Group1 and from the right-click context menu, click Rename.
    4. Rename the group to Patch.
  4. [Optional] Group the variables related to the substrate.
    1. In the model tree, select substrate_w, substrate_d and substrate_h.
    2. From the right-click context menu, select Group > Create.
    3. Select Group2 and from the right-click context menu, click Rename.
      Tip: Press F2 to use the keyboard shortcut to rename a selected item.
    4. Rename the group to Substrate.