Matlab and sorting single results to a matrix

Question

for i=1:1:k   %k = 100 people
   for j=1:1:l  %l = 5 orders
      Resultx = a + b + d(j); % cost of drink Resultx
      Resulty = f + g + c(j); % cost of food Resulty
   end
   Matrix(i) = [Resultsx1...j Resulty1...j]
end

Those % notes are for helping me express the problem I want to solve in my mind, and later on, in my script.

Lets claim that we want for each i to store values in a matrix of costs of the drinks and food it orders.

So for people i = 1,

1[1 5] %people 1, first order:  drink costs 1 and food costs 5
2[2 3] %people 1, second order: drink costs 2 and food costs 3
      ...
j[x y] %people 1, j order:      drink and food costs x and y
                 !!!       Matrix(1) = sort (j [x,y])    !!!

for people i = 2,

1[1 5] %people 2, first order:  drink costs 1 and food costs 5
2[2 3] %people 2, second order: drink costs 2 and food costs 3
     ...
j[x y] %people 2, j order:      drink and food costs x and y
       !!!       Matrix(2) = sort (j [x,y])    !!!

for people i = k,

1[1 5] %people k, first order:  drink costs 1 and food costs 5
2[2 3] %people k, second order: drink costs 2 and food costs 3
      ...
j[x y] %people k, j order:      drink and food costs x and y
            !!!       Matrix(i) = sort (j [x,y])    !!!

I want to form every result of each i^th iteration to a Matrix in ascending order

Matrix(i) = sort (j [x,y]).

Perhaps not the best paradigm, but thank you in advance.

Answer 1

(Two ways I understood your statement; I'm presuming you're interested in 2. solution. In this form Resultx and Resulty don't depend on i in any way, and therefore they'll be the same for all the "people").

1. Matrix is [ k x 2 ] array. Results from second loop are summed up!

Matrix = zeros(k, 2);                 % pre-allocate space

for i=1:1:k   %k = 100 people
    Resultx = 0;
    Resulty = 0;        
    for j=1:1:l  %l = 5 orders
        Resultx = Resultx + a + b + d(j);       % cost of drink Resultx
        Resulty = Resulty + f + g + c(j);       % cost of food Resulty
    end
    Matrix(i,:) = [Resultx, Resulty]  % save pair
end

Sorted = sortrows(Matrix, [1 2]);     % sort pairs

Last command sorts pairs, first by 1st column, then by 2nd column in ascending order. If you would like descending order for both criteria, you would use [-1 -2] instead. Combining ascending and descending is also possible (for example [-1 2]) but senselessness is questionable in this case.

2. Matrix is [ k x l x 2 ] array in which the results are kept individually and are not summed up in second loop.

Matrix = zeros(k, l, 2);              % pre-allocate space
Intermediate = zeros(l, 2);           % container used for sorting

for i=1:1:k   %k = 100 people
    for j=1:1:l  %l = 5 orders
        Resultx = a + b + d(j);       % cost of drink Resultx
        Resulty = f + g + c(j);       % cost of food Resulty
        Intermediate(j,:) = [Resultx, Resulty];  %save pair
    end
    Matrix(i,:,:) = sortrows(Intermediate, [1 2]);  % sort pairs
end

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Note: You should do avoid writing loops in Matlab and resort to vectorized solution wherever possible!