Expressions constraints, also known as Expressions, are similar to Relations constraints in that you create them to suit your needs, but instead use a spreadsheet-style interface to construct the expression. This spreadsheet interface is called the Expressions pane.

Expressions pane

The Expressions pane lets you use a more mathematical, and less graphic, method of constraining objects. This can be useful if you are familiar with commonly-used spreadsheet programs.

With an Expressions constraint, you enter data in cells instead of linking them together with connectors, as you do with Relations constraints. Once these elements are combined, they create an Expressions constraint that can be applied to a model.

Similar to Relations constraints, the Expressions method is useful for complex relationships, but in this case, they are helpful for creating more mathematically-based relationships.