penalty fitness value not changing

Hi

i am using ga for a mixed integer nonlinear constrained problem. i have got this plot result . the penality fitness value is constant along the generations and the run was terminated at genration 50. what does it mean?? i want also to understand the fundmental meaning of penality fitness value and what is the shape of the plot for a feasable solution

Answer 1

[Star Strider]

The penalty may not change.

In the options structure (in R2020b), I would use: 'PlotFcn',@gaplotbestf instead of whatever you are using. (I cannot tell what that is.)

[Nourhan Elsayed]

Dear Star Strider

thank you for your reply

i'm already using 'PlotFcn',"gaplotbestf". but i am using MATLAB-R2019b

my quistion is about the reasone that penality function not changing. i think it supposed to, at least, show a little change at the begining because of the diveresity of population, but after moving form one generation to another, when the population improves twords the elit solution, the penality function maight not changing, but at least at the begining it should be changing and converging.

may be i missed something

Answer 2

[Alan Weiss]

There may be only one feasible point that ga found.

Alan Weiss

MATLAB mathematical toolbox documentation