bility

Attributes
----------
learning_rate : float
    The current learning rate

t : int
    Timestep

ms : list, length = len(params)
    First moment vectors

vs : list, length = len(params)
    Second moment vectors

References
----------
:arxiv:`Kingma, Diederik, and Jimmy Ba (2014) "Adam: A method for
    stochastic optimization." <1412.6980>
c