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Tanh(Hyperbolic Tangent)
Estimated time to read: 1 minute
Tanh is a non-liner activation function commonly used in neural network.
It's derived from hyperbolic functions and is defined as:
tanh(x)=(e^x - e^-x)/(e^x + e^-x)
tanh(x) = 2 * sigmoid(2x) - 1
Output range:[-1, 1];