repeat the code with different value each time

Hi

I have a matrix w= 6x222 . I have 37 window. I want to repeat the code with different w 37 times. First I use the the first 6 columns of w so I use W=w(:,[1:6]); and I have the results then I use the following 6 columns i.e.W=w(:,[7:12]); and so on untile I have the last 6 columns W=w(:,[217:222]);

How can I do this iteration and extract the 37 solutions from each W.

Thanks in advance

Answer 1

[Jan]

w = rand(6, 222);
index = 1:6:size(w, 2);
result = zeros(1, numel(index));
for k = 1:numel(index)
    aw = w(:, index(k):index(k)+5);  % A 6x6 submatrix
    result = yourCalculations(aw);
end

I'd avoid the names "w" and "W", because the letters can be confused easily.

A more Matlab'ish way:

ww = reshape(w, 6, 6, []);

Now the calculations might be applicable to the 3D array ww directly without a loop. See e.g. pagemldivide or pagemtimes.

[Az.Sa]

Thank you very much!

so if my code as follow

clear all
R=readtable('return.1.indexFeb.csv');
R=table2array(R);
w=readmatrix('window.opt.w.05.csv');
W=w(:,[1:6]);
gamma = 2;
Aeq = [1 1 1 1 1 1];
beq = 1;
lb = zeros(6,1);
ub = ones(6,1);
x0=0.1667*ones(1,6);
u = @(x) 1/(1-gamma)*x.^(1-gamma); % CRRA utility 
obj = @(x)-sum(u(x*aw.'*R));

x = fmincon(obj,x0,[],[],Aeq,beq,lb,ub)

so I replace W=w(:,[1:6]) with

R=readtable('return.1.indexFeb.csv');
R=table2array(R);
w=readmatrix('window.opt.w.05.csv');
index = 1:6:size(w, 2);
result = zeros(1, numel(index));
for k = 1:numel(index)
    aw = w(:, index(k):index(k)+5);  % A 6x6 submatrix
    
gamma = 2;
Aeq = [1 1 1 1 1 1];
beq = 1;
lb = zeros(6,1);
ub = ones(6,1);
x0=0.1667*ones(1,6);
%x0=[.25,.25,.25,.25,0,0];
u = @(x) 1/(1-gamma)*x.^(1-gamma); % CRRA utility 
% u = @(x)  1 - exp(-gamma *x);
obj = @(x)-sum(u(x*aw.'*R));
options = optimoptions(@fmincon,'Algorithm','sqp','MaxIterations',1500);
x = fmincon(obj,x0,[],[],Aeq,beq,lb,ub);


end

and this is will calculate my x values corresponding to the w 37 times, correct ?

how can I save the results so I can use it in a different step.

[Jan]

for k = 1:numel(index)
    ...
    x(k) = ...
end