opacity variable

An opacity variable defines the opacity of a symbol based on a numeric data value returned from a field or expression. It is typically used to make features more or less prominent than others.

Opacity visual variables require the following:

1. A reference to a data value either from a field name or an Arcade expression.
2. At least two opacity stops that match data values to opacity values between 0 and 1. The opacity of symbols with data values between the designated stops are interpolated linearly.