Error when manipulating values on a matrix

Hello there,

I've got a few problems with my code. I'm going to explain: I have a matrix that is randomly generated: Populacao1 = [((randi([-1 1], n_individuos, n_centrais*int_tempo)))];

n_individuos=10 (or another number) n_centrais=2 (or more) and int_tempo = 10 (or more)

Populacao1 has only 1, -1 and 0 values. Now the problem begins.

I want to be able to keep 4 matrix (caulda_turbinado_c1, caudal_bombado_c1 and caulda_turbinado_c2, caudal_bombado_c2)

caudal_turbinado_c1 is the first (n_centrais*int_tempo)/2 where the the value equals 1 and caudal_bombado_c2 is when it equals -1. caudal_turbinado_c2 and bombado_c2 are the same in the other half of the matrix. the problem is that it doesn't work. Don't know why :s

for i=1:n_individuos
  for j=1:int_tempo*n_centrais
      if j <= int_tempo
      if(Populacao1(i,j)==1)

            caudal_turbinado_c1(i,j) = 100;

        if(Populacao1(i,j)==-1) 

            caudal_bombado_c1(i,j)=200;
        end

        end
        end

        if j > int_tempo && j<=int_tempo*n_centrais
          if(Populacao1(i,j)==1)

            caudal_turbinado_c2(i,j-int_tempo) = 400;

            if(Populacao1(i,j)==-1)  

            caudal_bombado_c2(i,j-int_tempo)=200;
            end
        end
        end   

    end
end

Thanks in advance

[Azzi Abdelmalek]

If you provide data to test your code, it will be helpful

[Jan]

Pleas explain "it doesn't work" with any details. Do you get an error message or do the results differ from your expectations?

[André Pacheco]

The result is different from my expectations. I was expecting that my could would divide the matrix into to halfs, and in the first one it would put 100 if =1 and 200 if the value =-1 and in the second half it would put 400 if value =1 and 200 if value =-1. If the value was 0 it would do nothing. The thing is that it doesnt work. Don't know why. I resolve this spliting the matrix, do the process and then merge the matrix back together. But it would be much better if this work.

[André Pacheco]

Azzi i think i've put all the values in the explanation. What is missing? thanks for the help!

Answer 1

[per isakson]

The statement

    caudal_bombado_c1(ii,jj)=200;

in

    if (Populacao1(ii,jj)==1)
        caudal_turbinado_c1(ii,jj) = 100;
        if(Populacao1(ii,jj)==-1)
            caudal_bombado_c1(ii,jj)=200;
        end
    end

will never be executed, since

    Populacao1(ii,jj)

cannot be identical to +1 and -1 at the same time.

.

Modified code - I'm just guessing

You should do some exercises with the debugging features in Matlab. Put some break-points in the code and run

    >> [ ctc1, cbc1, ctc2, cbc2 ] = cssm();

where

    function    [ ctc1, cbc1, ctc2, cbc2 ] = cssm()
        n_individuos = 10;
        int_tempo    =  6;
        n_centrais   =  2;
        Populacao1   = randi( [ -1, 1 ],  n_individuos, int_tempo * n_centrais );

        [ ctc1, cbc1, ctc2, cbc2 ] ...
         = cssm_( n_individuos, int_tempo, n_centrais, Populacao1 );
    end
    function varargout = cssm_( n_individuos, int_tempo, n_centrais, Populacao1 )

        caudal_turbinado_c1 = nan( n_individuos, int_tempo*n_centrais );
        caudal_bombado_c1   = nan( n_individuos, int_tempo*n_centrais );
        caudal_turbinado_c2 = nan( n_individuos, int_tempo*n_centrais );
        caudal_bombado_c2   = nan( n_individuos, int_tempo*n_centrais );

        for ii=1:n_individuos
            for jj=1:int_tempo*n_centrais
                if jj <= int_tempo
                    if (Populacao1(ii,jj)==1)
                        caudal_turbinado_c1(ii,jj) = 100;
                    elseif(Populacao1(ii,jj)==-1)
                        caudal_bombado_c1(ii,jj)=200;
                    else
                        % do nothing
                    end
                end
                if jj > int_tempo && jj<= int_tempo * n_centrais
                    if(Populacao1(ii,jj)==1)
                        caudal_turbinado_c2(ii,jj-int_tempo) = 400;
                    elseif(Populacao1(ii,jj)==-1)
                        caudal_bombado_c2(ii,jj-int_tempo)=200;
                    else
                        % do nothing
                    end
                end
            end
        end
        varargout = { caudal_turbinado_c1, caudal_bombado_c1 ...
                    , caudal_turbinado_c2, caudal_bombado_c2 };
    end