minimum value is selected always from last iteration

part_machine=[1  0  0  1  0  1  1;
0  1  1  1  0  0  1;
1  0  0  1  1  0  0;
1  0  0  0  1  0  1;
1  1  0  0  0  1  0;
0  1  0  0  0  1  1];

demand=[600;550;620;500;590;600];
numIterations=3;

for k=1:numIterations

      rand_cell_assigntomachines=randi([0,1],7,3);

      Part_cell=part_machine*rand_cell_assigntomachines;

      Part_cell(Part_cell>=1)=1;

      no_of_movements=sum(Part_cell,2)-1;

      movement_cost=sum(bsxfun(@times,no_of_movements,demand))

    end
  minval=min(movement_cost)
   the result is 
  movement_cost =

          5110

movement_cost =

          6920

movement_cost =

          6300

minval =

          6300

but in 3 iterations, 6300 is not minimum value.. I checked it and the value which is always picked as min is from the last iteration.. why is this so?

Answer 1

[Walter Roberson]

Assign to movement_cost(k) instead of overwriting all of movement_cost

[summyia qamar]

minval=min(movement_cost(k))..?or where?

[Walter Roberson]

Inside the loop,

        movement_cost(k)=sum(bsxfun(@times,no_of_movements,demand));

After the loop, stay with your existing

    minval=min(movement_cost)

[summyia qamar]

I'm running this code.

part_machine=[1  0  0  1  0  1  1
          0  1  1  1  0  0  1
          1  0  0  1  1  0  0
          1  0  0  0  1  0  1
          1  1  0  0  0  1  0
          0  1  0  0  0  1  1];
      demand=[600;550;620;500;590;600];
      numIterations=100;
      for k=1:numIterations
          rand_cell=randi([0,1],7,3);
          if all(sum(rand_cell,2)==1);
         Part_cell(k)=part_machine*rand_cell;
          end
         Part_cell(Part_cell>=1)=1
          no_of_movements=sum(Part_cell,2)-1;
          movement_cost(k)=sum(bsxfun(@times,no_of_movements,demand));
      end
      minval=min(movement_cost);
      [rand_cell minval(ones(7,1))]

the idea behind this code is * generate rand_cell * select that rand_cell in which sum of rows is 1 * multiply Part_machine matrix with that rand_cell * then apply the other functions on part_machine matrix * then at the end select the minval from all iterations * result is displayed with that rand_cell matrix which has generated the minimum value

now the result I'm getting is like this

ans =

             1           0           1        6920
             1           0           0        6920
             0           1           0        6920
             1           1           0        6920
             1           1           1        6920
             1           1           1        6920
             1           0           1        6920

it is not the rand_cell matrix according to condition

all(sum(rand_cell,2)==1)

where is the problem?