calculate the frequency of element in a matrix

matrix = [1 1 1 1 4 5 5 7 14 14 14 14 14 15 15 15 17 17 ; 2 6 7 7 7 2 3 5 2 3 4 5 6 3 4 4 3 6 ; 7 7 5 7 6 3 2 5 6 6 7 6 3 3 2 5 5 5 ; 0 0 1 0 0 1 0 1 0 0 0 0 1 1 1 1 1 1]

I don't know how i can calculate how many times a number appears in the first row and at the same time calculate how many times a one appears in the fourth row when the element in the first row remains the same. For example my desired output would be:

matrix2 = [1 4 5 7 14 15 17 ; 
           4 1 2 1  5  3  2 ; 
           1 0 1 1  1  3  2]

[Jan]

It would be more convenient, if you post the data in a format, which can be used by copy and paste. It is much easier to provide code, when we can test it.

Answer 1

[Andrei Bobrov]

matrix1 = [1 1 1 1 4 5 5 7 14 14 14 14 14 15 15 15 17 17 ; 
           2 6 7 7 7 2 3 5 2 3 4 5 6 3 4 4 3 6 ; 
           7 7 5 7 6 3 2 5 6 6 7 6 3 3 2 5 5 5 ; 
           0 0 1 0 0 1 0 1 0 0 0 0 1 1 1 1 1 1];
[a,~,c] = unique(matrix1(1,:));
[jj,ii] = ndgrid(c,1:2);
out = [a;accumarray([ii(:),jj(:)],[ones(size(matrix1,2),1);matrix1(4,:)'])];

Answer 2

[Jan]

With FEX: RunLength:

[B, N, BI] = RunLength(matrix(1, :));
V = RunLength(1:length(B), N);
K = accumarray(V.', matrix(4, :).').';

Result = [B; N; K];

[jonas jonas]

when I try this function matlab gives an error Undefined function 'RunLength' for input arguments of type 'double'.

[Jan]

Did you see the "with FEX: RunLength" link? Follow the link to get the code for RunLength. You find a fast MEX-function there, which requires a compilation. If speed does not matter that much, use RunLength_M from this submission.