threshold-minority3

3-input minority gate. Outputs 1 when at most 1 of 3 inputs is high. Complement of majority3.

Function

minority3(a, b, c) = 1 if (a + b + c) <= 1, else 0

Truth Table

a	b	c	sum	out
0	0	0	0	1
0	0	1	1	1
0	1	0	1	1
0	1	1	2	0
1	0	0	1	1
1	0	1	2	0
1	1	0	2	0
1	1	1	3	0

Architecture

Single neuron: weights [-1, -1, -1], bias 1

Fires when: -a - b - c + 1 >= 0, i.e., sum <= 1

Parameters

Inputs	3
Outputs	1
Neurons	1
Layers	1
Parameters	4
Magnitude	4

Usage

from safetensors.torch import load_file
import torch

w = load_file('model.safetensors')

def minority3(a, b, c):
    inp = torch.tensor([float(a), float(b), float(c)])
    return int((inp @ w['neuron.weight'].T + w['neuron.bias'] >= 0).item())

print(minority3(0, 0, 1))  # 1
print(minority3(0, 1, 1))  # 0

License

MIT