FL Set Membership Function (MF array) VI
- Updated2025-07-30
- 6 minute(s) read
Modifies the shape, color, or points of a membership function for a linguistic variable. You can modify a membership function from a fuzzy system or from an array of membership functions. The data type you wire to the fuzzy system in input determines the polymorphic instance to use.

Inputs/Outputs
membership function index
—
membership function index specifies the index of the membership function you want to modify. membership function index corresponds to the order in which the membership function was created.
membership functions in
—
membership functions in specifies an array of membership functions. Wire the membership functions out output from another VI to the membership functions in input of this VI.
name
—
name specifies the name of the membership function, or linguistic term, you want to modify.
shape
—
shape specifies the shape of the function that determines the degrees of membership for the linguistic variable.
points
—
points specifies the values of the linguistic variable corresponding to the base and top points, in order from left to right and base to top, of the membership function. The degree of membership of the linguistic variable within the linguistic term name is 0 at the base points and 1 at the top points. Specify one point for a singleton function, three points for a triangle function, and four points for trapezoid, sigmoid, Gaussian, or user-defined functions.
error in (no error)
—
error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
color
—
color specifies the color of the membership function when you view the membership function in the Fuzzy System Designer. You can wire a color box constant to this input.
user-defined membership function shapes
—
user-defined
shape index
—
user-defined shape index specifies the index of the user-defined shape that determines the degrees of membership for the linguistic variable. This parameter is applicable only if you set shape to User-Defined. Define the user-defined shapes in the user-defined membership function shapes array in both the FL New Fuzzy System VI and the User-Defined instance of the FL Create Membership Function VI.
membership functions out
—
membership functions out returns an array of membership functions. Wire the membership functions out output of this VI to the membership functions in input of another VI.
error out
—
error out contains error information. This output provides standard error out functionality. |
membership function index
—
membership functions in
—
name
—
shape
—
points
—
color
—
error in (no error)
—
membership functions out
—
name
—
shape
—
points
—
color
—
user-defined shape index
—
error out
—