# Boolean Functions Implemented by Multiplexers

Electrical engineers often use multiplexers to implement Boolean functions. What is the correct technical term for this model of computation? Is it Decision Tree model or is there another name?

• Can you explain your question in more detail? – Yuval Filmus Dec 18 '18 at 22:33
• You are using multiplexers ( relays if you like) to implement Boolean functions instead of logic gates. Engineers use this technique to build circuits with large truth tables because it is easy to just hardwire the values of the truth table into the input lines of the multiplexer. So what do you call this method of computation, is it relay logic, decision tree ( because the multiplexers are in the tree arrangement for any N input) ? – William Hird Dec 18 '18 at 22:42
• You can call it a multiplexer if you wish, though truth table might be more common. It is a rather boring model of computation, since all functions have the same complexity. – Yuval Filmus Dec 18 '18 at 22:43
• What do you mean " all the functions have the same complexity" ? – William Hird Dec 18 '18 at 22:45
• All functions of length $n$ have the same complexity, or rather, there is no meaningful way to define a complexity measure for functions in this model. – Yuval Filmus Dec 18 '18 at 22:45