Variable

This command allows a variable of type Angle or Length to be defined in order to be able to create proportionality relations between the dimensions (like for example such a dimension must be equal to twice another, the dimension value being unknown).

Creation Stages / Use:

Select the 2D or 3D sketch > Constraints > Variable... command from the drop-down menu. In a Draft document, select the Sketch > Constraints > Variable... command from the drop-down menu.

Choose the variable's type (Angle or Length).
Enter the variable's name.

Modifications / Additional information:

When the variable is created, you can associate it with a dimension by selecting the dimension, and using the popup command Make variable.

The variable name will then be displayed between the characters < > after the dimension text and this dimension will no longer drive the geometry, its value will be recalculated during the modification of the geometry (via modification of the sketch or via displacement of elements referenced by the dimension).

You can then use the command Equations to create equations between the variables (like for example: b = 2 * a).

There is no chronology in the resolution of an equation, only the relation is important.

Take for example the case of a variable "a" associated with a dimension which has the value of 60mm and a variable "b" whose equation is: b = 2*a. When the variable "b" is associated with a dimension whose value is 100mm, TopSolid can either modify the value of the 100 mm dimension and make it go to 120mm, or modify the value of the 60mm dimension and make it go to 200mm.

The variables are specific to each sketch, it is not possible to share them between several sketches or use them outside the sketch.