for loop doesn't seem to loop

Hi I have the following code

    for i = 1:8760

    A = [PVtech(i,:) WTtech(i,:)];

    b = demand(i);

    f = [CRF*PVtechcost(i,:).*PVcap(i,:)./PVtech(i,:) CRF*WTtechcost(i,:).*WTcap(i,:)./WTtech(i,:)];

    x(i) = linprog(f, A,b,[], [], lb);
end

I am trying to optimise linprog over the 8760 data set but I can't seem to get the loop going for each row. therefore when I run it is get a size of A to be 1x30 (when it should be 8760 by 30) Does anyone see where I have coded wrongly ?

thank you

Answer 1

[Ryan]

You're not specifying the row of A that you are writing the data to, so each loop it just places [PVtech(i,:) WTtech(i,:)] into the first row of A.

Try:

for m = 1:8760
    A(m,:) = [PVtech(m,:) WTtech(m,:)];
    b = demand(m);
    f = [CRF*PVtechcost(m,:).*PVcap(m,:)./PVtech(m,:) CRF*WTtechcost(m,:).*WTcap(m,:)./WTtech(m,:)];
    x(m) = linprog(f, A,b,[], [], lb);
end

[Sean de Wolski]

same with x I believe.

Answer 2

[Thomas]

use ii instead of i since i is built into matlab for complex numbers

 for ii=1:8760

 ii  % to show which loop you are in
  A(ii,:)=[PVtech(ii,:) WTtech(ii,:)];

You also might have to change your

 x(ii,:) = linprog(f, A(ii,:),b,[], [], lb)

Though I do feel that your program was running right just that you were only seeing the last A which will be 1x30 since it was being overwritten.

to see if you are going through the loop

just output ii

[Andrew Alkiviades]

Still no luck! the ii output returns - 1 the size of A is still (1,30) and the size of b is still (1,1) A should be (8760x30) and b should be 8760x1

[Ryan]

Are you sure that you are showing us everything that is happening in the code? Doing something simplified such as:

for ii = 1:8760
   A(ii,:) = 1;
end

returns an 8760x1 vector for me.

Answer 3

[Andrew Alkiviades]

Thanks guys - I have made the changes you suggest,

I now get, from the code below, two rows of A so I have a size(A) = (2,30) where A should in fact be 8760x30

I don't see why the loop doesn't go through all the 8760 rows as it is

for i = 1:8760

    A(i,:) = [PVtech(i,:) WTtech(i,:)];

    b = demand(i);

    f = [CRF*PVtechcost(i,:).*PVcap(i,:)./PVtech(i,:) CRF*WTtechcost(i,:).*WTcap(i,:)./WTtech(i,:)];

    %options == optimset('LargeScale', 'off', 'Simplex', 'on');

    x(i,:) = linprog(f, A,b,[], [], lb,[])

     end