Problem using ga without equality constraints
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Hello to all,
I am trying to optimize the geometry of N discreet systems using certain non-linear constraints (Inequalities). The inequalities are generated with the help of a seperate function (con_PK.m, as shown below).
function [c] = con_PK(Koordinaten,N,Xd,Yd,r,Rd)
%UNTITLED3 Summary of this function goes here
% Detailed explanation goes here
%Koordinaten = sym ('Koordinaten', [N,2]);
for i=1:N
for j=1:N
c1 (i,j) = 2*r-((Koordinaten(i,1)-Koordinaten(j,1))^2+(Koordinaten(i,2)-Koordinaten(j,2))^2)^0.5; %Constraint1
end
c1 (i,j+1) = ((Koordinaten(i,1)-Xd)^2+(Koordinaten(i,2)-Yd)^2)^0.5 - (Rd-r); %Constraint2
end
f=1;
for j=1:N
e=f+N-j-1;
c(f:e,1)=c1(j+1:N,j);
%f=f+(N-j);
f=e+1;
end
c(0.5*(N*(N-1)):0.5*(N*(N-1))+N-1,1)=c1(:,N+1);
end
and the main code as follows,
%Erstellt von Prathamesh
clc;
close all;
clear all;
%Eingabe von Parametern
%PK: Eine Notepaddatei mit allen Parametern ausgelesen
ID = importdata ('Input Data.txt');
Rd=ID(1,1);
r=ID(2,1);
N= ID(3,1);
%Erzeuge Kreis mit Radius Rd & Mittelpunkt (Rd,Rd)
%PK: Hier legen wir die 'Origin' fest
Xd=Rd;
Yd=Rd;
%PK: Als nächstes muss eine Basisgeometrie von Litzen erzeugt werden
%(willürlich)
th=0:pi/100:2*pi;
X=Rd*cos(th)+Xd;
Z=Rd*sin(th)+Yd;
%plot(X,Z);
%hold on
%Hier wird die Berechnung bassiert auf dem geneteschin Algorithmus gestartet
Koordinaten = sym ('x', [N,2]);
%Koordinaten (:,2)= sym ('y', [N,1]);
c1 = sym ('c',[0.5*(N^2+N-2),1]);
syms Lb
Function = @ (x) sum (Koordinaten (:,2)) >= 0;
variables = N;
c1 = con_PK(Koordinaten, N,Xd,Yd,r,Rd);
q = @(x) c1;
sol=ga(@Function,variables,[],[],[],[],[],[], q);
However, I always get following errors and unable to understand the reason. The most important thing to be noted is that, I do not have any equality constraints and do not know, if they can be categorically neglected by MATLAB 'ga' algorithm.
Error using Optimierung_PK>@(x)c1
Too many output arguments.
Error in createAnonymousFcn>@(x)fcn(x,FcnArgs{:}) (line 11)
fcn_handle = @(x) fcn(x,FcnArgs{:});
Error in constrValidate (line 23)
[cineq,ceq] = nonlcon(Iterate.x');
Error in gacommon (line 125)
[LinearConstr, Iterate,nineqcstr,neqcstr,ncstr] = constrValidate(NonconFcn, ...
Error in ga (line 363)
NonconFcn,options,Iterate,type] = gacommon(nvars,fun,Aineq,bineq,Aeq,beq,lb,ub, ...
Error in Optimierung_PK (line 39)
sol=ga(@Function,variables,[],[],[],[],[],[], q);
Caused by:
Failure in initial user-supplied nonlinear constraint function evaluation.
Thanking you in advance for any inputs.
Sincerely,
Prathamesh Khorgade.
0 Comments
Answers (1)
Walter Roberson
on 9 Nov 2020
Edited: Walter Roberson
on 9 Nov 2020
q = @(x) c1;
is wrong. It accepts a single input, and ignores the input, and instead returns whatever the content of c1 was without any substitution of values.
Instead
q = matlabFunction(c1, 'vars', {symvar(c1)});
2 Comments
Walter Roberson
on 9 Nov 2020
You are using u as a nonlinear constraint function. Such a function must return two values.
q1 = matlabFunction(c1, 'vars', {symvar(c1)});
q = @(x) deal(q1(x), []); %empty nonlinear equalities
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