why the penalty of ga, when all the population violates the nonlinear constraints, is smaller than the penalty of feasible populations?

Question

Emebet Gedlu 2022-11-17

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1853673-why-the-penalty-of-ga-when-all-the-population-violates-the-nonlinear-constraints-is-smaller-than-t

回答： Jasvin 2023-9-21

I have integer problem with nonlinear constraints. So, at the beggining there are only few integer options (the problem's boundary increases through time) and sometimes all the populations my violate the non-linear constraint. For example, the penalityt value of the first generation with feasible population is 5, then ga assignes penality value 1 when the entire population in the second generation violates the non-linear constraint.

4 个评论
显示 2更早的评论隐藏 2更早的评论

Matt J 2022-11-17

编辑：Matt J 2022-11-17

How are you observing the population size? How are you observing the penalty values? What code can we run to illustrate what you are seeing?

Emebet Gedlu 2022-11-17

在 MATLAB Online 中打开

Well, I have a very complex problem but here is the idea.

f=@(n_Tx)CMPC_vector(n_Tx,u_past,decide,Setup,Hist_temp, plan_OP,trainedNet,Rem_step); 
nonlcon=@(x)MaxTorqueLim(x,Setup,Rem_step,decide);
options=optimoptions('ga', 'Display', 'iter','MaxTime',120,...
    'PopulationSize',PP_Size,'UseVectorized',true,...
    'CrossoverFraction',0.5,'EliteCount',floor(1+PP_Size/3),'MaxStallGenerations',15);
[n_Tx_float,f_val]=ga(f,Setup.NInput*Rem_step,[],[],[],[],lb,ub,nonlcon,1:Setup.NInput*Rem_step,options);
function JJ= CMPC_vector(x,u_past,decide,Setup,Hist, plan_OP,trainedNet,Rem_step)
    ...
end 

I just put a brake point in the first line of the "CMPC_vector" function to obesrve what is in x. Then I give higher penality value if it is empy, but what appear in the display is just 1 all way till the maximum stall.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Jasvin 2023-9-21

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1853673-why-the-penalty-of-ga-when-all-the-population-violates-the-nonlinear-constraints-is-smaller-than-t#answer_1314777

Hi Emebet,

So, this is a problem that exists with all optimization algorithms in MATLAB. The following MATLAB Answers post would help you gain more insight into what is happening and provide helpful links:

https://www.mathworks.com/matlabcentral/answers/287101-matlab-why-ga-algorithm-does-not-satisfy-non-linear-constraint-in-its-population-creation

Hope this helps!

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

why the penalty of ga, when all the population violates the nonlinear constraints, is smaller than the penalty of feasible populations?

4 个评论
显示 2更早的评论隐藏 2更早的评论

回答（1 个）

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

另请参阅

类别

标签

Community Treasure Hunt

why the penalty of ga, when all the population violates the nonlinear constraints, is smaller than the penalty of feasible populations?

4 个评论 显示 2更早的评论隐藏 2更早的评论

回答（1 个）

0 个评论 显示 -2更早的评论隐藏 -2更早的评论

另请参阅

类别

标签

Community Treasure Hunt

4 个评论
显示 2更早的评论隐藏 2更早的评论

0 个评论
显示 -2更早的评论隐藏 -2更早的评论