The hard sigmoid activation is defined as:
0
ifif x <= -3
1
ifx >= 3
(x/6) + 0.5
if-3 < x < 3
It's a faster, piecewise linear approximation of the sigmoid activation.
See also
Other activations: activation_elu()
activation_exponential()
activation_gelu()
activation_leaky_relu()
activation_linear()
activation_log_softmax()
activation_mish()
activation_relu()
activation_relu6()
activation_selu()
activation_sigmoid()
activation_silu()
activation_softmax()
activation_softplus()
activation_softsign()
activation_tanh()