ReLU has a hard corner at zero — its gradient jumps abruptly from 0 to 1. Swish smooths that out by weighting each input by its own sigmoid, giving a curve that dips slightly negative before rising, instead of clamping flat to zero:
Task: write swish(values) applying this element-wise, rounded to 4 decimal places.
σ(0) = 0.5 and 0 × 0.5 = 0.