threshold-or / README.md
CharlesCNorton
Add optimality note: exhaustive enumeration confirms magnitude 3 is minimum
73126c7
---
license: mit
tags:
- pytorch
- safetensors
- threshold-logic
- neuromorphic
---
# threshold-or
A 1-of-2 threshold gate. One active input is enough to fire.
## Circuit
```
x y
β”‚ β”‚
β””β”€β”¬β”€β”˜
β–Ό
β”Œβ”€β”€β”€β”€β”€β”€β”€β”
β”‚ w: 1,1β”‚
β”‚ b: -1 β”‚
β””β”€β”€β”€β”€β”€β”€β”€β”˜
β”‚
β–Ό
OR(x,y)
```
## Mechanism
Same weights as AND, but bias -1 instead of -2. The lower bar means a single vote suffices:
| x | y | sum | output |
|---|---|-----|--------|
| 0 | 0 | -1 | 0 |
| 0 | 1 | 0 | 1 |
| 1 | 0 | 0 | 1 |
| 1 | 1 | 1 | 1 |
AND and OR are the same circuit with different thresholds. This is the essence of threshold logic: the bias determines how many inputs must agree.
## Parameters
| | |
|---|---|
| Weights | [1, 1] |
| Bias | -1 |
| Total | 3 parameters |
## Optimality
Exhaustive enumeration of all 25 weight configurations at magnitudes 0-3 confirms this circuit is **already at minimum magnitude (3)**. There is exactly one valid configuration at magnitude 3, and no valid configurations exist below it.
## Properties
- Linearly separable
- De Morgan dual: OR(x,y) = NOT(AND(NOT(x), NOT(y)))
- Generalizes to n-input OR with weights all 1, bias -1
## Usage
```python
from safetensors.torch import load_file
import torch
w = load_file('model.safetensors')
def or_gate(x, y):
inputs = torch.tensor([float(x), float(y)])
return int((inputs * w['weight']).sum() + w['bias'] >= 0)
```
## Files
```
threshold-or/
β”œβ”€β”€ model.safetensors
β”œβ”€β”€ model.py
β”œβ”€β”€ config.json
└── README.md
```
## License
MIT