Exemplo n.º 1
0
    def get_updates(self, params, constraints, loss):
        grads = self.get_gradients(loss, params)
        self.updates = [(self.iterations, self.iterations + 1.)]

        t = self.iterations + 1
        lr_t = self.lr / (1 - K.pow(self.beta_1, t))

        for p, g, c in zip(params, grads, constraints):
            # zero init of 1st moment
            m = K.variable(np.zeros(K.get_value(p).shape))
            # zero init of exponentially weighted infinity norm
            u = K.variable(np.zeros(K.get_value(p).shape))

            m_t = (self.beta_1 * m) + (1 - self.beta_1) * g
            u_t = K.maximum(self.beta_2 * u, K.abs(g))
            p_t = p - lr_t * m_t / (u_t + self.epsilon)

            self.updates.append((m, m_t))
            self.updates.append((u, u_t))
            self.updates.append((p, c(p_t)))  # apply constraints
        return self.updates
Exemplo n.º 2
0
    def get_updates(self, params, constraints, loss):
        grads = self.get_gradients(loss, params)
        self.updates = [(self.iterations, self.iterations+1.)]

        t = self.iterations + 1
        lr_t = self.lr / (1 - K.pow(self.beta_1, t))

        for p, g, c in zip(params, grads, constraints):
            # zero init of 1st moment
            m = K.variable(np.zeros(K.get_value(p).shape))
            # zero init of exponentially weighted infinity norm
            u = K.variable(np.zeros(K.get_value(p).shape))

            m_t = (self.beta_1 * m) + (1 - self.beta_1) * g
            u_t = K.maximum(self.beta_2 * u, K.abs(g))
            p_t = p - lr_t * m_t / (u_t + self.epsilon)

            self.updates.append((m, m_t))
            self.updates.append((u, u_t))
            self.updates.append((p, c(p_t)))  # apply constraints
        return self.updates
Exemplo n.º 3
0
def hinge(y_true, y_pred):
    return K.mean(K.maximum(1. - y_true * y_pred, 0.), axis=-1)
Exemplo n.º 4
0
def squared_hinge(y_true, y_pred):
    return K.mean(K.square(K.maximum(1. - y_true * y_pred, 0.)), axis=-1)
Exemplo n.º 5
0
def hinge(y_true, y_pred):
    return K.mean(K.maximum(1. - y_true * y_pred, 0.), axis=-1)
Exemplo n.º 6
0
def squared_hinge(y_true, y_pred):
    return K.mean(K.square(K.maximum(1. - y_true * y_pred, 0.)), axis=-1)