How to sum up unique arrays in the matrix

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Hi everyone,
Suppose the matrix A is as follows:
A = [10 1 180
10 1 40
10 1 40
10 1 160
10 2 10
10 3 410
10 1 10
10 1 50
12 1 30
12 1 30
12 2 45
12 3 60
65 1 15
65 1 360
];
I want to sum up the values in column three if the value in column one and two are similar. The output matrix should be like:
B = [10 1 420
10 2 10
10 3 410
10 1 60
12 1 60
12 2 45
12 3 60
65 1 375
];

Accepted Answer

Azzi Abdelmalek
Azzi Abdelmalek on 4 Apr 2016
Edited: Azzi Abdelmalek on 4 Apr 2016
Edit
A = [10 1 180
10 1 40
10 1 40
10 1 160
10 2 10
10 3 410
10 1 10
10 1 50
12 1 30
12 1 30
12 2 45
12 3 60
65 1 15
65 1 360
];
idx=any([0 0;diff(A(:,1:2))],2)
jdy=cumsum(idx)
b=accumarray(jdy+1,1:numel(jdy),[],@(x) sum(A(x,3)))
[ii,jj,kk]=unique(jdy)
out=[A(jj,1:2) b]

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