7. The system according to claim 1, in which said if-part membership values producing means comprises means for defining a membership function having a triangular shape in accordance with a single point of change and two gradients and means for calculating the if-part membership value by means of the binary data and the triangular membership function.
7. The system according to claim 1, in which said if-part membership values producing means comprises means for defining a membership function having a triangular shape in accordance with a single point of change and two gradients and means for calculating the if-part membership value by means of the binary data and the triangular membership function. 8. The system according to claim 7, in which said membership value producing means further comprises means for changing the shape of the if-part membership function by setting the value corresponding to one of the gradients to zero.