activations.py 文件源码

def derivative(self, input=None):
        """Backward propagation.

        Returns
        -------
        float32 
            The derivative of Elliot function. 
        """
        last_forward = 1 + np.abs(input * self.steepness) if input else self.last_forward
        return 0.5 * self.steepness / np.power(last_forward, 2)


# elliot-end
# symmetric-elliot-start