Altering the membership functions of fuzzy sets

   

initfz	Initialize fuzzy functions
<fuzzyname>	name of the fuzzy structure
[-fs <setname>]	name of the target set
[-lock]	locking similar sets to each other
setfzs	Macro to update a membership function of a fuzzy set
<fuzzyname>	name of the fuzzy structure
-fs <setname>	name of the fuzzy set
-vals <index>=<value> ...;	indexed point values ended with ';'
[-lock]	locking similar sets to each other
getfzpnt	Find the nearest point of the membership functions
<fuzzyname>	name of the fuzzy structure
-v <value>	the value to be located
[-lock]	check only suitable points for locked sets

These commands are meant for setting or getting the shapes of membership functions. The membership functions are specified through the names of the fuzzy sets, the indexes of the corner points or values of these corners in the x-axis. The indexes for each type of fuzzy membership function are illustrated in the figure below. If the parameter -lock has been given for these commands, then the sets are handled as if they were locked to each other. getfzpnt can be used to find the nearest point among suitable points.

Example: This example demonstrates commands which are needed to create a drag-and-drop functionality to an interface for updating the access points of membership functions.

NDA> load boston.dat
NDA> mkfz fz1 -f boston.dis
NDA> addfzs fz1 -fs nearToCity -t 8
NDA> addfzs fz1 -fs farFromCity -t 8
NDA> initfz fz1
...
# Drag started at x-value 8.0, so find the nearest point of
# current membership function for location 8.0
NDA> getfzpnt fz1 -v 8.0
8.460867                 # The exact value of the point
nearToCity               # Set name
4                        # Index
...
# Create here drag-and-drop graphical output and, when the drop
# event is received, perform the following command:
NDA> setfzs fz1 -fs nearToCity -v 4=<x_value_for_drop>;
...