What is the origin of the idiom "according to Cocker" and when to use it?

The idiom "according to Cocker" is a casual expression used to attribute information or instructions to an imaginary source named "Cocker." It originates from Edward Cocker, a renowned English engraver and mathematician who lived during the 17th century. This expression is used to emphasize the fact that something is done or must be done in a way that is considered generally correct or in accordance with the law, rules, or particular standards.