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%% Copyright (Federico Giai Pron) | ||
% This file has been created by Federico Giai Pron, energy engineering with a 2nd level master in energy management for automotive powertrains done after the graduation. For any question, write to federico.giaipron@gmail.com | ||
%% Clear | ||
clear all | ||
close all | ||
clc | ||
%% Data | ||
Data = []; | ||
%% PSO | ||
% Sizes | ||
Sett.LengthX = 3; % Select the number of variables . Its value must be coherent with the number of columns of XGuess, XLim and VLim | ||
Sett.LengthObjFun = 3; % Select the number of objective functions. Its value must be coherent with the number of rows of Sett.ObjFunType and Sett.ObjFunPrio | ||
% Guess value of X | ||
XGuess = zeros(1,Sett.LengthX); % Select the guess value of X | ||
% Limit values of X and V | ||
XLim(1,:) = [0.2,0.02,5]; % Select the lower limit value of X | ||
XLim(2,:) = [0.4,0.04,7]; % Select the upper limit value of X | ||
VLim(1,:) = -max(abs(XLim))/150; % Select the lower limit value of V | ||
VLim(2,:) = +max(abs(XLim))/150; % Select the upper limit value of V | ||
% Objective functions | ||
Sett.ObjFunType(1,1) = "min"; % Select the optimization type for the objective function 1 | ||
Sett.ObjFunType(2,1) = "min"; % Select the optimization type for the objective function 2 | ||
Sett.ObjFunType(3,1) = "max"; % Select the optimization type for the objective function 3 | ||
Sett.ObjFunPrio(1,1) = 1.0; % Select the priority of the objective function 1 | ||
Sett.ObjFunPrio(2,1) = 2.5; % Select the priority of the objective function 2 | ||
Sett.ObjFunPrio(3,1) = 1.0; % Select the priority of the objective function 3 | ||
% PSO parameters | ||
win = 0.3; % Select the initial weight (the weight is linearly reduced from win to wend during the simulation) | ||
wend = 0.0; % Select the final weight (the weight is linearly reduced from win to wend during the simulation) | ||
c1 = 0.5; % Select the coefficient applied to "X-Xpbest" for the calculation of V | ||
c2 = 5; % Select the coefficient applied to "X-Xgbest" for the calculation of V | ||
% Number of particles / families | ||
Sett.NumPar = 1000; % Select the number of particles of each family | ||
Sett.NumFam = 1; % Select the number of families (the PSO is restarted for Sett.NumFam times and only the optimal one is considered) | ||
% Termination criteria | ||
Sett.NumIterMin = 0; % Select the minimum number of iterations | ||
Sett.NumIterMax = 50; % Select the maximum number of iterations | ||
Sett.VarRelObjFunTrgt = 0*ones(1,Sett.LengthObjFun); % Select the relative variation at which the simulation is terminated | ||
Sett.RelErrAvObjFunTrgt = 0*ones(1,Sett.LengthObjFun); % Select the relative error at which the simulation is terminated | ||
% Robustness | ||
Sett.NumIterBtwnRestarts = inf; % Select the number of iterations between each restart | ||
Sett.NumIterBtwnZeroTests = inf; % Select the number of iterations between each "zero-test" (the variables are set 1 by 1 equal to a zero value to check if a better objective function is got) | ||
% Flags | ||
Sett.FlagXGuess = false; % Select "true" to initialize X to XGuess, "false" to initialize it randomly | ||
Sett.FlagPlots = true; % Select "true" to generate figures and plots | ||
% Run PSO | ||
[XOpt,ObjFunOpt] = Optimization_PSO_v05(XGuess,XLim,VLim,win,wend,c1,c2,Data,Sett); % Run the PSO | ||
%% Plot |
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%% Copyright (Federico Giai Pron) | ||
% This file has been created by Federico Giai Pron, energy engineering with a 2nd level master in energy management for automotive powertrains done after the graduation. For any question, write to federico.giaipron@gmail.com | ||
%% Define the objective functions | ||
function [ObjFun] = ObjFun_fun(X,Data) | ||
%% Input | ||
% Convert the global optimization variable vector, X, into the optimization | ||
% variables | ||
A = X(1); | ||
B = X(2); | ||
C = X(3); | ||
%% Objective functions | ||
% Calculate the objective functions | ||
Ec = 376.3 + 697*A + 2900*B - 116.3*C - 56667*B^2 + 10.67*C^2 + 11333*A*B - 36.7*A*C; | ||
Ra = 0.64590 - 0.5461*A - 7.703*B + 0.02107*C + 1.3056*(A^2) + 160.35*(B^2) - 1.083*A*B - 0.07181*A*C; | ||
MRR = 0.03670 + 0.00224*A + 0.536*B - 0.01211*C - 7.28*B^2 + 0.001043*C^2 + 0.645*A*B - 0.0104*B*C; | ||
%% Output | ||
% Collect the objective functions into a single row vector ObjFun | ||
ObjFun(1,1) = Ec; | ||
ObjFun(1,2) = Ra; | ||
ObjFun(1,3) = MRR; | ||
end |
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%% Copyright (Federico Giai Pron) | ||
% This file has been created by Federico Giai Pron, energy engineering with a 2nd level master in energy management for automotive powertrains done after the graduation. For any question, write to federico.giaipron@gmail.com | ||
%% Particle Swarm Optimization (PSO) | ||
function [Xfbest,ObjFunfbest] = Optimization_PSO_v04(XGuess,XLim,VLim,win,wend,c1,c2,Data,Sett) | ||
% Parameters | ||
LengthX = Sett.LengthX; % Import the number of variables from the Sett object | ||
LengthObjFun = Sett.LengthObjFun; % Import the number of objective functions from the Sett object | ||
NumPar = Sett.NumPar; % Import the number of particles from the Sett object | ||
% Initialization | ||
X = zeros(NumPar,LengthX); | ||
Xpbest = zeros(NumPar,LengthX); | ||
Xgbest = zeros(1,LengthX); | ||
Xfbest = zeros(1,LengthX); | ||
Xzerotest = zeros(1,LengthX); | ||
V = zeros(NumPar,LengthX); | ||
ObjFun = zeros(NumPar,LengthObjFun); | ||
ObjFunpbest = zeros(NumPar,LengthObjFun); | ||
ObjFunpbestguest = zeros(NumPar,LengthObjFun); | ||
ObjFungbest = zeros(1,LengthObjFun); | ||
ObjFungbestold = zeros(1,LengthObjFun); | ||
ObjFunfbest = zeros(1,LengthObjFun); | ||
ObjFunpRelDis = zeros(NumPar,LengthObjFun); | ||
ObjFunpRelDisguest = zeros(NumPar,LengthObjFun); | ||
ObjFungRelDis = zeros(NumPar,LengthObjFun); | ||
ObjFungRelDisguest = zeros(NumPar,LengthObjFun); | ||
ObjFunfRelDis = zeros(1,LengthObjFun); | ||
AvObjFun = zeros(1,LengthObjFun); | ||
ObjFungbestPlots = zeros(Sett.NumIterMax,Sett.NumFam,LengthObjFun); | ||
AvObjFunPlots = zeros(Sett.NumIterMax,Sett.NumFam,LengthObjFun); | ||
VarRelObjFunPlots = zeros(Sett.NumIterMax,Sett.NumFam,LengthObjFun); | ||
RelErrAvObjFunPlots = zeros(Sett.NumIterMax,Sett.NumFam,LengthObjFun); | ||
% Iterate for each family | ||
for IndexFam = 1:1:Sett.NumFam | ||
% Output the current family number | ||
fprintf('- IndexFam: %3i out of %3i\n',IndexFam,Sett.NumFam); | ||
% Initialization | ||
IndexIter = 0; % Initialize the number of iterations for the current family | ||
FlagContinue = true; % Initialize the FlagContinue flag to true | ||
% Iterate until the FlagContinue is equal to true | ||
while(FlagContinue == true) | ||
% Update the current iteration number | ||
IndexIter = IndexIter + 1; | ||
% Output the current iteration number | ||
fprintf('-- IndexIter: %3i out of %3i\n',IndexIter,Sett.NumIterMax); | ||
% Iterate for each particle | ||
for IndexPar = 1:1:NumPar | ||
% Initialize X and V | ||
if IndexIter == 1 || rem(IndexIter,Sett.NumIterBtwnRestarts) == 0 | ||
if(Sett.FlagXGuess == true) | ||
for IndexX = 1:1:LengthX | ||
X(IndexPar,IndexX) = XGuess(IndexX); | ||
V(IndexPar,IndexX) = VLim(1,IndexX) + (VLim(2,IndexX) - VLim(1,IndexX))*rand(1); | ||
end | ||
else | ||
for IndexX = 1:1:LengthX | ||
X(IndexPar,IndexX) = XLim(1,IndexX) + (XLim(2,IndexX) - XLim(1,IndexX))*rand(1); | ||
V(IndexPar,IndexX) = VLim(1,IndexX) + (VLim(2,IndexX) - VLim(1,IndexX))*rand(1); | ||
end | ||
end | ||
% Update X and V | ||
else | ||
r1 = rand(1); | ||
r2 = rand(1); | ||
for IndexX = 1:1:LengthX | ||
w = win - (win - wend) * IndexIter / Sett.NumIterMax; | ||
V(IndexPar,IndexX) = min(max(w*V(IndexPar,IndexX) + c1*r1*(Xpbest(IndexPar,IndexX)-X(IndexPar,IndexX)) + c2*r2*(Xgbest(IndexX)-X(IndexPar,IndexX)),VLim(1,IndexX)),VLim(2,IndexX)); | ||
X(IndexPar,IndexX) = min(max(X(IndexPar,IndexX) + V(IndexPar,IndexX) ,XLim(1,IndexX)),XLim(2,IndexX)); | ||
end | ||
end | ||
end | ||
% Plot in real-time | ||
if(Sett.FlagPlots == true) | ||
if(IndexIter == 1) | ||
h1 = []; | ||
h2 = []; | ||
h3 = []; | ||
end | ||
[h1,h2,h3] = Plot(XLim,X,h1,h2,h3); | ||
end | ||
% Calculate the objective functions | ||
for IndexPar = 1:1:NumPar | ||
fprintf('--- IndexPar: %3i out of %3i\n',IndexPar,NumPar); | ||
ObjFun(IndexPar,:) = ObjFun_fun(X(IndexPar,:),Data); | ||
for IndexObjFun = 1:1:LengthObjFun | ||
if(Sett.ObjFunType(IndexObjFun) == "max") | ||
ObjFun(IndexPar,IndexObjFun) = -ObjFun(IndexPar,IndexObjFun); | ||
end | ||
end | ||
end | ||
% Determine Xpbest | ||
for IndexPar = 1:1:NumPar | ||
if IndexIter == 1 | ||
for IndexX = 1:1:LengthX | ||
Xpbest(IndexPar,IndexX) = X(IndexPar,IndexX); | ||
end | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFunpbest(IndexPar,IndexObjFun) = ObjFun(IndexPar,IndexObjFun); | ||
end | ||
else | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFunpRelDis(IndexPar,IndexObjFun) = Sett.ObjFunPrio(IndexObjFun)*(ObjFun(IndexPar,IndexObjFun)-ObjFunpbest(IndexPar,IndexObjFun))/abs(ObjFunpbest(IndexPar,IndexObjFun)); | ||
end | ||
if(sum(ObjFunpRelDis(IndexPar,:)) <= 0 || isnan(sum(ObjFunpRelDis(IndexPar,:))) == true) | ||
for IndexX = 1:1:LengthX | ||
Xpbest(IndexPar,IndexX) = X(IndexPar,IndexX); | ||
end | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFunpbest(IndexPar,IndexObjFun) = ObjFun(IndexPar,IndexObjFun); | ||
end | ||
end | ||
end | ||
end | ||
% Xgbest determination | ||
if IndexIter == 1 | ||
for IndexX = 1:1:LengthX | ||
Xgbest(IndexX) = Xpbest(1,IndexX); | ||
end | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFungbest(IndexObjFun) = ObjFunpbest(1,IndexObjFun); | ||
end | ||
end | ||
for IndexPar = 1:1:NumPar | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFungRelDis(IndexPar,IndexObjFun) = Sett.ObjFunPrio(IndexObjFun)*(ObjFunpbest(IndexPar,IndexObjFun)-ObjFungbest(IndexObjFun))/abs(ObjFungbest(IndexObjFun)); | ||
end | ||
if(sum(ObjFungRelDis(IndexPar,:)) <= 0 || isnan(sum(ObjFungRelDis(IndexPar,:))) == true) | ||
for IndexX = 1:1:LengthX | ||
Xgbest(IndexX) = Xpbest(IndexPar,IndexX); | ||
end | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFungbestold(IndexObjFun) = ObjFungbest(IndexObjFun); | ||
ObjFungbest(IndexObjFun) = ObjFunpbest(IndexPar,IndexObjFun); | ||
end | ||
end | ||
end | ||
% Output Xgbest and ObjFungbest | ||
fprintf('--'); | ||
for IndexObjFun = 1:1:LengthObjFun | ||
if(ObjFungbest(IndexObjFun) == 0) | ||
if(Sett.ObjFunType(IndexObjFun) == "min") | ||
fprintf(' ObjFungbest(%i): %-+1.16e,',IndexObjFun,+ObjFungbest(IndexObjFun)); | ||
elseif(Sett.ObjFunType(IndexObjFun) == "max") | ||
fprintf(' ObjFungbest(%i): %-+1.16e,',IndexObjFun,-ObjFungbest(IndexObjFun)); | ||
end | ||
else | ||
if(Sett.ObjFunType(IndexObjFun) == "min") | ||
fprintf(' ObjFungbest(%i): %-+1.10e,',IndexObjFun,+ObjFungbest(IndexObjFun)); | ||
elseif(Sett.ObjFunType(IndexObjFun) == "max") | ||
fprintf(' ObjFungbest(%i): %-+1.10e,',IndexObjFun,-ObjFungbest(IndexObjFun)); | ||
end | ||
end | ||
end | ||
for IndexX = 1:1:LengthX | ||
if(IndexX < LengthX) | ||
if(Xgbest(IndexX) == 0) | ||
fprintf(' Xgbest(%i) = %-+1.16d,',IndexX,Xgbest(IndexX)); | ||
else | ||
fprintf(' Xgbest(%i) = %-+1.10d,',IndexX,Xgbest(IndexX)); | ||
end | ||
else | ||
if(Xgbest(IndexX) == 0) | ||
fprintf(' Xgbest(%i) = %-+1.16d\n',IndexX,Xgbest(IndexX)); | ||
else | ||
fprintf(' Xgbest(%i) = %-+1.10d\n',IndexX,Xgbest(IndexX)); | ||
end | ||
end | ||
end | ||
% Perform the zero-test | ||
if rem(IndexIter,Sett.NumIterBtwnZeroTests) == 0 && IndexIter ~= 1 | ||
Xpbestguest = Xpbest; | ||
for IndexX = 1:1:LengthX | ||
% 1 element of X per time set equal to 0 | ||
for IndexPar = 1:1:NumPar | ||
Xpbestguest(IndexPar,IndexX) = Xzerotest(IndexX); | ||
end | ||
% ObjFun calculation | ||
for IndexPar = 1:1:NumPar | ||
ObjFunpbestguest(IndexPar,:) = ObjFun_fun(Xpbestguest(IndexPar,:),Data); | ||
for IndexObjFun = 1:1:LengthObjFun | ||
if(Sett.ObjFunType(IndexObjFun) == "max") | ||
ObjFunpbestguest(IndexPar,IndexObjFun) = -ObjFunpbestguest(IndexPar,IndexObjFun); | ||
end | ||
end | ||
end | ||
% Xpbest determination | ||
for IndexPar = 1:1:NumPar | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFunpRelDisguest(IndexPar,IndexObjFun) = Sett.ObjFunPrio(IndexObjFun)*(ObjFunpbestguest(IndexPar,IndexObjFun)-ObjFunpbest(IndexPar,IndexObjFun))/abs(ObjFunpbest(IndexPar,IndexObjFun)); | ||
end | ||
if(sum(ObjFunpRelDisguest(IndexPar,:)) <= 0 || isnan(sum(ObjFunpRelDisguest(IndexPar,:))) == true) | ||
for IndexX2 = 1:1:LengthX | ||
Xpbest(IndexPar,IndexX2) = Xpbestguest(IndexPar,IndexX2); | ||
end | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFunpbest(IndexPar,IndexObjFun) = ObjFunpbestguest(IndexPar,IndexObjFun); | ||
end | ||
end | ||
end | ||
% Xgbest determination | ||
for IndexPar = 1:1:NumPar | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFungRelDisguest(IndexPar,IndexObjFun) = Sett.ObjFunPrio(IndexObjFun)*(ObjFunpbestguest(IndexPar,IndexObjFun)-ObjFungbest(IndexObjFun))/abs(ObjFungbest(IndexObjFun)); | ||
end | ||
if(sum(ObjFungRelDisguest(IndexPar,:)) <= 0 || isnan(sum(ObjFungRelDisguest(IndexPar,:))) == true) | ||
for IndexX2 = 1:1:LengthX | ||
Xgbest(IndexX2) = Xpbestguest(IndexPar,IndexX2); | ||
end | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFungbestold(IndexObjFun) = ObjFungbest(IndexObjFun); | ||
ObjFungbest(IndexObjFun) = ObjFunpbestguest(IndexPar,IndexObjFun); | ||
end | ||
end | ||
end | ||
% Xpbestguest restore to old value | ||
for IndexPar = 1:1:NumPar | ||
Xpbestguest(IndexPar,IndexX) = Xpbest(IndexPar,IndexX); | ||
end | ||
end | ||
end | ||
% Determine FlagContinue flag | ||
for IndexObjFun = 1:1:LengthObjFun | ||
AvObjFun(IndexObjFun) = mean(ObjFun(:,IndexObjFun)); | ||
VarRelObjFun(IndexObjFun) = abs((ObjFungbest(IndexObjFun) - ObjFungbestold(IndexObjFun))/ObjFungbestold(IndexObjFun)); | ||
RelErrAvObjFun(IndexObjFun) = abs(AvObjFun(IndexObjFun)-ObjFungbest(IndexObjFun))/ObjFungbest(IndexObjFun); | ||
end | ||
FlagContinue = true; | ||
for IndexObjFun = 1:1:LengthObjFun | ||
if((VarRelObjFun(IndexObjFun) < Sett.VarRelObjFunTrgt(IndexObjFun) && RelErrAvObjFun(IndexObjFun) < Sett.RelErrAvObjFunTrgt(IndexObjFun)) || IndexIter >= Sett.NumIterMax) | ||
FlagContinue = false; | ||
end | ||
end | ||
% Plots - Pt.1 | ||
if(Sett.FlagPlots == true) | ||
for IndexObjFun = 1:1:LengthObjFun | ||
if(Sett.ObjFunType(IndexObjFun) == "min") | ||
ObjFungbestPlots(IndexIter,IndexFam,IndexObjFun) = +ObjFungbest(IndexObjFun); | ||
elseif(Sett.ObjFunType(IndexObjFun) == "max") | ||
ObjFungbestPlots(IndexIter,IndexFam,IndexObjFun) = -ObjFungbest(IndexObjFun); | ||
end | ||
end | ||
AvObjFunPlots(IndexIter,IndexFam,:) = AvObjFun; | ||
VarRelObjFunPlots(IndexIter,IndexFam,:) = VarRelObjFun; | ||
RelErrAvObjFunPlots(IndexIter,IndexFam,:) = RelErrAvObjFun; | ||
end | ||
end | ||
% Determine Xfbest | ||
if IndexFam == 1 | ||
Xfbest = Xgbest; | ||
ObjFunfbest = ObjFungbest; | ||
end | ||
for IndexObjFun = 1:1:LengthObjFun | ||
ObjFunfRelDis(IndexObjFun) = Sett.ObjFunPrio(IndexObjFun)*(ObjFungbest(IndexObjFun)-ObjFunfbest(IndexObjFun))/abs(ObjFunfbest(IndexObjFun)); | ||
end | ||
if(sum(ObjFunfRelDis) <= 0 || isnan(sum(ObjFunfRelDis)) == true) | ||
Xfbest = Xgbest; | ||
ObjFunfbest = ObjFungbest; | ||
end | ||
% Output Xfbest and ObjFunfbest | ||
fprintf('- '); | ||
for IndexObjFun = 1:1:LengthObjFun | ||
if(ObjFunfbest(IndexObjFun) == 0) | ||
if(Sett.ObjFunType(IndexObjFun) == "min") | ||
fprintf(' ObjFunfbest(%i): %-+1.16e,',IndexObjFun,+ObjFunfbest(IndexObjFun)); | ||
elseif(Sett.ObjFunType(IndexObjFun) == "max") | ||
fprintf(' ObjFunfbest(%i): %-+1.16e,',IndexObjFun,-ObjFunfbest(IndexObjFun)); | ||
end | ||
else | ||
if(Sett.ObjFunType(IndexObjFun) == "min") | ||
fprintf(' ObjFunfbest(%i): %-+1.10e,',IndexObjFun,+ObjFunfbest(IndexObjFun)); | ||
elseif(Sett.ObjFunType(IndexObjFun) == "max") | ||
fprintf(' ObjFunfbest(%i): %-+1.10e,',IndexObjFun,-ObjFunfbest(IndexObjFun)); | ||
end | ||
end | ||
end | ||
for IndexX = 1:1:LengthX | ||
if(IndexX < LengthX) | ||
if(Xfbest(IndexX) == 0) | ||
fprintf(' Xfbest(%i) = %-+1.16d,',IndexX,Xfbest(IndexX)); | ||
else | ||
fprintf(' Xfbest(%i) = %-+1.10d,',IndexX,Xfbest(IndexX)); | ||
end | ||
else | ||
if(Xfbest(1,IndexX) == 0) | ||
fprintf(' Xfbest(%i) = %-+1.16d\n',IndexX,Xfbest(IndexX)); | ||
else | ||
fprintf(' Xfbest(%i) = %-+1.10d\n',IndexX,Xfbest(IndexX)); | ||
end | ||
end | ||
end | ||
end | ||
% Adjust sign at the end of optimization | ||
for IndexObjFun = 1:1:LengthObjFun | ||
if(Sett.ObjFunType(IndexObjFun) == "max") | ||
ObjFunfbest(IndexObjFun) = -ObjFunfbest(IndexObjFun); | ||
end | ||
end | ||
% Plots - Pt.2 | ||
if(Sett.FlagPlots == true) | ||
for IndexObjFun = 1:1:LengthObjFun | ||
% ObjFungbest | ||
figure; | ||
for IndexFam = 1:1:Sett.NumFam | ||
semilogy(1:1:length(ObjFungbestPlots(:,IndexFam,IndexObjFun)),ObjFungbestPlots(:,IndexFam,IndexObjFun),'LineWidth',2); | ||
hold on; | ||
end | ||
title('ObjFun_{g,best}'); | ||
xlabel('NumIter'); | ||
ylabel('ObjFun_{g,best}'); | ||
grid on; | ||
end | ||
end | ||
end |
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