40 Algorithms Every Programmer Should Know

Hyperbolic tangent (tanh)

The tanh function is similar to the sigmoid function, but it has the ability to give a negative signal as well. The following diagram illustrates this:

The y function is as follows:

It can be implemented by the following Python code:

def tanh(x):     numerator = 1-np.exp(-2*x)     denominator = 1+np.exp(-2*x)     return numerator/denominator

Now let's look at the softmax function.