Math Nerds, Help!

Here’s another scenario for the latter case that gave me headaches.

I have a series of products that each have a set of features. Say printers.

Printer 1 has inkjet, WiFi, 2-sided, network printing and color as key features.
Printer 2 has inkjet, 2-sided and color as key features.
Printer 3 has laser, WiFi, network printing as key features.
Printer N

The user inputs the features they want. Say WiFi, 2-sided and color. In one case you might want to show all printers that have ALL those options, in another case you might want to show printers that have ANY of those options.

I get that. But there’s a difference between {x,b} in that one of the elements is in the set, where as {a,b} has none of the values. Not sure if there’s a way to capture that distinction using this type of math.

Two sets are disjoint just when they share no members, i.e. A ∩ B = {} (their intersection is equivalent to the null set). What you might be after is an operator which determines whether or not sets share any members, in which case you can define it in terms of whether or not the sets are disjoint.

And you could do the second in terms of sets that are not disjoint.

You can just say what you want to say. Fancy notation isn’t important. If what you want to talk about is “Those printers whose feature-sets have at least one element in common with the selected feature-set”, you can just go ahead and talk about it. We could put this in notation for you, in myriad different fashions, but I don’t think it would buy you anything…

This should help illustrate the concept

There are likers of Venn diagrams who aren’t people?

Well, my dogs like them when I make them out of food.