merge two matrices together

I have two matrices as follows

-----------------------------------------

40  40  40  40
41  41  41  41
42  42  42  42
43  44  43  44
43  45  44  44
44  48  45  49
45  50  49  51
50  51  51  52
51  52  52  53
52  53  53  54

------------------------------------------

1282  1687  2501  1466
870  929  644  1141
345  103  736  133
765  7484  1434  3267
2796  461  7021  2143
4689  212  363  241
549  320  343  218
219  761  415  249
187  316  684  868
85  309  271  395
----------------------------------------

Each column and row of the first matrix corresponds to the second matrix

I would like to generate a matrix as follows

40  1282  1687  2501  1466
41  870  929  644  1141
42  345  103  736  133
43  2796+765 0  1434  0
44  4689  7484  7021   3267+2143
45  549  461  363  0
46  0  0  0  0
47  0  0  0  0
48  0  212  0  0
49  0  0  343  241
50  219  320  0  0
51  189  761  415  218
52  85  316  684  249
53  0  309  271  868
54  0  0  0  395

As it can be seen , the first matrix was merged and one column which present all the data of the first matrix is appeared. each row and column of the second matrix corresponds to the first matrix and those that had similar values are sum and those values that do not exist a zero will be replaced.

Answer 1

[Roger Stafford]

If M1 and M2 are your two arrays (of like size), get your desired result in array M3:

 [m,n] = size(M1);
 [u,~,p] = unique(M1(:));
 q = reshape(repmat(1:n,m,1),[],1);
 M3 = [u,accumarray([p,q],M2(:),[size(u,1),n])];

Answer 2

[José-Luis]

ii = [40  40  40  40
41  41  41  41
42  42  42  42
43  44  43  44
43  45  44  44
44  48  45  49
45  50  49  51
50  51  51  52
51  52  52  53
52  53  53  54];
d = [1282   1687  2501  1466
870  929  644  1141
345  103  736  133
765  7484  1434  3267
2796  461  7021  2143
4689  212  363  241
549  320  343  218
219  761  415  249
187  316  684  868
85  309  271  395];

left_side = (min(ii):max(ii))';
mySum = @(idx) sum(d.*(ii==idx),1);
your_result = [left_side  cell2mat(arrayfun(@(x) mySum(x),left_side, 'uniformoutput', false))];

[Niki]

That is much better but the last two rows are missing , can you please try to get the same results as I mentioned above?

[José-Luis]

left_side = (min(ii(:)):max(ii(:)))'; %To get the proper range.
mySum = @(idx) sum(d.*(ii==idx),1);
your_result = [left_side  cell2mat(arrayfun(@(x) mySum(x),left_side,'uniformoutput',false))];

Please accept an answer if it helps you.

Answer 3

[Iain]

You ought to be able to mod this to give you exactly what you want - I've made some assumptions that are probably not true.

for i = 1:Rows

New(i,1) = i;

for j = 1:Columns

New(i,1+j) = sum(Old(Indices(i,j),j));

end

end

[Niki]

Lets say the first matrix is called M1 and second M2

[rows, columns]=size (m1);

However, indices is undefined , I dont know what is this function and cannot be find by matlab

[Iain]

M1 is "Indices". Maybe "rownumbers" would be better. - I assumed that it started at 1. M2 is what I called "Old".

Rows would be max(Indices(:)). Columns is as you guessed.

[Niki]

I don't know where I am mistaken

>> [rows, columns]=size (m1); for i = 1:rows

New(i,1) = i;

for j = 1:columns

New(i,1+j) = sum(m2(m1(i,j),j));

end

end ??? Attempted to access m2(1282,1); index out of bounds because size(m2)=[10,4].

[Iain]

You've got m1 and m2 the wrong way round.

Try these mods: New(i,1) = i; should be New(i,1) = i+39;

New(i,1+j) = sum(Old(Indices(i,j),j)); should be New(i,1+j) = sum(Old(Indices(i,j)-39,j));

[Niki]

the same error happened

[Iain]

m1 = indices = [40 40 40 40....

m2 = Old = [1282 ...

[Niki]

unfortunately does not work , please perform it yourself you will see that does not work

Answer 4

[Andrei Bobrov]

ii = [40  40  40  40
41  41  41  41
42  42  42  42
43  44  43  44
43  45  44  44
44  48  45  49
45  50  49  51
50  51  51  52
51  52  52  53
52  53  53  54];

d = [1282   1687  2501  1466
870  929  644  1141
345  103  736  133
765  7484  1434  3267
2796  461  7021  2143
4689  212  363  241
549  320  343  218
219  761  415  249
187  316  684  868
85  309  271  395];

a = min(ii(:)):max(ii(:));
[l1, l2] = ismember(ii,a);
i1 = [l2(l1) kron((1:size(ii,2))',ones(size(ii,1),1))];
out = [a(:), accumarray(i1,d(:))]

[Niki]

Thanks for your effort but it does not work completely, if you have look , I don't get the first column values with this script nor do I get some rows

[Andrei Bobrov]

correct