I was solving the Four Peaks Problem[1] using ga function in MATLAB.
This problem has an integer constraint and the solution is expected to be in integers, but MATLAB’s ga function returns non-integer solution, although they are almost integers.
Following is the code. I expect to see
oz = [21.0000 79.0000], and fval = -179.0000
but I see
oz = [21.0000 79.0010], and fval = -179.0010
Well, they are, like I said, almost integers, so I surely can interpret them, but I was just curious. Is this expected output? Or is the function missing something during the postprocessing?
%% Setup
close
clear
clc

% for reproducibility
rng(1,’twister’)

% length of the bit string
N = 100;

% threshold
T = 20;

% Pass in fixed parameters to objfun.
objfun = @(oz) -four_peaks(oz,T,N);

% constraints
INTCON = [1, 1]; % integer constraints: Both o and z must be integers.
lb = [0, 0]; % Both o and z cannot be negative.
ub = [N,N]; % Both o and z cannot be greater than the length of the bit string.
A = [1,1]; b = N; % inequality constraint: o+z < length of the bit string.

%% Solve
% Solve
[oz,fval,exitflag,output,population,scores] = ga(objfun,2,A,b,[],[],lb,ub,[],INTCON);

%% Report
disp(oz)
disp(-fval)

%% Object Function
function y = four_peaks(x, T, N)

if x(1) > T && x(2) > T
y = max(x) + N;
else
y = max(x);
end
endI was solving the Four Peaks Problem[1] using ga function in MATLAB.
This problem has an integer constraint and the solution is expected to be in integers, but MATLAB’s ga function returns non-integer solution, although they are almost integers.
Following is the code. I expect to see
oz = [21.0000 79.0000], and fval = -179.0000
but I see
oz = [21.0000 79.0010], and fval = -179.0010
Well, they are, like I said, almost integers, so I surely can interpret them, but I was just curious. Is this expected output? Or is the function missing something during the postprocessing?
%% Setup
close
clear
clc

% for reproducibility
rng(1,’twister’)

% length of the bit string
N = 100;

% threshold
T = 20;

% Pass in fixed parameters to objfun.
objfun = @(oz) -four_peaks(oz,T,N);

% constraints
INTCON = [1, 1]; % integer constraints: Both o and z must be integers.
lb = [0, 0]; % Both o and z cannot be negative.
ub = [N,N]; % Both o and z cannot be greater than the length of the bit string.
A = [1,1]; b = N; % inequality constraint: o+z < length of the bit string.

%% Solve
% Solve
[oz,fval,exitflag,output,population,scores] = ga(objfun,2,A,b,[],[],lb,ub,[],INTCON);

%% Report
disp(oz)
disp(-fval)

%% Object Function
function y = four_peaks(x, T, N)

if x(1) > T && x(2) > T
y = max(x) + N;
else
y = max(x);
end
end I was solving the Four Peaks Problem[1] using ga function in MATLAB.
This problem has an integer constraint and the solution is expected to be in integers, but MATLAB’s ga function returns non-integer solution, although they are almost integers.
Following is the code. I expect to see
oz = [21.0000 79.0000], and fval = -179.0000
but I see
oz = [21.0000 79.0010], and fval = -179.0010
Well, they are, like I said, almost integers, so I surely can interpret them, but I was just curious. Is this expected output? Or is the function missing something during the postprocessing?
%% Setup
close
clear
clc

% for reproducibility
rng(1,’twister’)

% length of the bit string
N = 100;

% threshold
T = 20;

% Pass in fixed parameters to objfun.
objfun = @(oz) -four_peaks(oz,T,N);

% constraints
INTCON = [1, 1]; % integer constraints: Both o and z must be integers.
lb = [0, 0]; % Both o and z cannot be negative.
ub = [N,N]; % Both o and z cannot be greater than the length of the bit string.
A = [1,1]; b = N; % inequality constraint: o+z < length of the bit string.

%% Solve
% Solve
[oz,fval,exitflag,output,population,scores] = ga(objfun,2,A,b,[],[],lb,ub,[],INTCON);

%% Report
disp(oz)
disp(-fval)

%% Object Function
function y = four_peaks(x, T, N)

if x(1) > T && x(2) > T
y = max(x) + N;
else
y = max(x);
end
end genetic algorithm, four peaks problem MATLAB Answers — New Questions

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