Dimension Parameters
A dimension parameter allows you to identify dimensions in a geometry project and assign a variable to the dimension, which allows you to vary those dimensions within an analysis. The initial value of the dimension parameter is the length that appears in your circuit. This is the nominal value of the variable assigned to the dimension parameter. If you change the nominal value of the variable, then the circuit is redrawn with that length.
There are three types of dimension parameters: anchored, symmetric, and radial. For brevity, we refer to anchored dimension parameters as anchored parameters, symmetric dimension parameters as symmetric parameters, and radial dimension parameters as radial parameters for the remainder of this discussion. An anchored parameter allows you to fix one end of a parameter then vary its length extending from that point. A symmetric parameter allows you to fix the center point of a dimension parameter and vary the distance it extends on each side. A radial parameter allows you to fix one end of a parameter then radiate out from that fixed point; the direction is not restricted to the x or y direction, but may extend at an angle. The three dimension parameter types are described in detail in the links below.
Symmetrical Dimension Parameters