(float, optional): term added to the denominator to improve
numerical stability (default: 1e-8)
weight_decay
optional weight decay penalty. (default: 0)
momentum
(float, optional): momentum factor (default: 0)
centered
(bool, optional) : if TRUE, compute the centered RMSProp,
the gradient is normalized by an estimation of its variance
weight_decay (float, optional): weight decay (L2 penalty) (default: 0)