M .task/taskchampion.sqlite3 A "Zettelkasten/Permanent Notes/20251223161108-andre-platzer.md" A "Zettelkasten/Permanent Notes/20251223162450-web-of-science.md" A "Zettelkasten/Permanent Notes/20251223162954-snowballing.md" A "Zettelkasten/Permanent Notes/20251223163648-deterministic-parity-automata.md" A "Zettelkasten/Permanent Notes/20251223165340-mealy-machines.md" A "Zettelkasten/Permanent Notes/20251223170627-finite-state-machines.md" A "Zettelkasten/Permanent Notes/20251223171835-moore-machines.md"
50 lines
1.3 KiB
Markdown
50 lines
1.3 KiB
Markdown
---
|
|
id: 20251223165340
|
|
title: Mealy Machines
|
|
type: permanent
|
|
created: 2025-12-23T21:53:40Z
|
|
modified: 2025-12-23T22:38:18Z
|
|
tags: []
|
|
---
|
|
|
|
# Mealy Machines
|
|
|
|
Mealy machines are a formalization of a system that has
|
|
states drawn as nodes and transitions drawn from state to
|
|
state.
|
|
|
|
From Wikipedia:
|
|
```
|
|
A mealy machine is a finite state machine whose
|
|
output values are determined by both its current state, and
|
|
the current inputs.
|
|
```
|
|
|
|
Mealy machines can also be defined as a six-tuple:
|
|
|
|
$$(S, S_0, \Sigma, \Lambda, T, G)$$
|
|
|
|
where
|
|
- S is the finite set of states
|
|
- S_0 is the start state
|
|
- $\Sigma$ is the input alphabet
|
|
- $\Lambda$ is the output alphabet
|
|
- $T : S \times \Sigma \rightarrow S$ is the state
|
|
transition function
|
|
- $G : S \times \Sigma \rightarrow \Lambda$ is the output
|
|
function
|
|
|
|
Mealy machines have the advantage that they generally can
|
|
produce smaller sized automata (aka less states). This is
|
|
because transitions themselves in a Mealy machine are states
|
|
in a Moore machine. The state of 'opening' in a Moore
|
|
machine is the transition itself in a Mealy machine. Outputs
|
|
aren't just based on state, so it isn't necesary to create a
|
|
state to produce an output like a Moore machine. An output
|
|
action can be created with the current state AND the input
|
|
together.
|
|
|
|
## Related
|
|
[[Finite State Machines]]
|
|
|