| import torch | |
| from safetensors.torch import load_file | |
| def load_model(path='model.safetensors'): | |
| return load_file(path) | |
| def signbit4(a3, a2, a1, a0, weights): | |
| """Returns sign bit (MSB) of 4-bit number. 1 = negative in 2's complement.""" | |
| inp = torch.tensor([float(a3), float(a2), float(a1), float(a0)]) | |
| return int((inp @ weights['neuron.weight'].T + weights['neuron.bias'] >= 0).item()) | |
| if __name__ == '__main__': | |
| w = load_model() | |
| print('signbit4 truth table:') | |
| for i in range(16): | |
| a3, a2, a1, a0 = (i >> 3) & 1, (i >> 2) & 1, (i >> 1) & 1, i & 1 | |
| result = signbit4(a3, a2, a1, a0, w) | |
| signed_val = i if i < 8 else i - 16 | |
| print(f' {a3}{a2}{a1}{a0} (unsigned={i:2d}, signed={signed_val:+3d}) -> sign={result}') | |