This information is part of the Business Simulation Library (BSL). Please support this work and ► donate.
The function returns the degree of membership using the product
of two sigmoidal functions given the real input
x and the parameters shape parameter for the
s-shaped transition area a, center of the
s-shaped transition area b, shape parameter
of the z-shaped transition area c, and center
of the z-shaped transition area d of the
function.
y := sigmf(x, a = a, c = b) * sigmf(x, a = -c, c = d);
Functions.psigmf(x, a, b, c,
d);
Functions.psigmf( 8, a=2, b=3, c=5, d=8); // 0.4999773.. Functions.psigmf( 6.9, a=2, b=3, c=5, d=8); // 0.9955219.. Functions.psigmf( 3, a=2, b=3, c=5, d=8); // 0.4999999.. Functions.psigmf( 10, a=2, b=3, c=5, d=8); // 4.53978e-05
evalmf, rampmf, trimf, trapmf, smf, sigmf, gaussmf, gbellmf
function psigmf import BusinessSimulation.Functions.sigmf; extends BusinessSimulation.Icons.Function; input Real x "Input value for which the degree of membership is to be computed"; input Real a "Shape parameter controlling the width of s-shaped transition area (higher values → steeper transition)"; input Real b "Center of s-shaped transition area"; input Real c "Shape parameter controlling the width of z-shaped transition area (higher values → steeper transition)"; input Real d "Center of z-shaped transition area"; output Real y "Degree of membership"; end psigmf;