Digits that repeat in an n by m matrix

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If I have a multidimensional array of n by m and I want to count the number of digits that repeat in each row of the array.
Ex:
Columns 1 through 7
9 5 2 1 5 3 3
1 8 3 1 7 4 3
1 3 1 1 8 6 4
1 3 1 6 4 2 1
2 1 6 3 2 2 1
2 3 1 1 7 5 4
1 1 4 2 1 8 6
Columns 8 through 10
2 2 5
2 2 6
4 2 4
2 9 7
1 9 1
2 1 5
5 4 5
in the end i want:
first row i have : number 1 -> 1; 2-> 3; 3 -> 2,...
I try a few, but i don´t have any sucess..
someone can help me?
  2 Comments
Matt J
Matt J on 5 Mar 2022
in the end i want:
first row i have : number 1 -> 1; 2-> 3; 3 -> 2,...
That is not the number of digits that repeat in the first row (which would be 3). That is the number of repetitions of each digit.

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Accepted Answer

Matt J
Matt J on 5 Mar 2022
A = [ 9 5 2 1 5 3 3 2 2 5
1 8 3 1 7 4 3 2 2 6
1 3 1 1 8 6 4 4 2 4
1 3 1 6 4 2 1 2 9 7
2 1 6 3 2 2 1 1 9 1
2 3 1 1 7 5 4 2 1 5
1 1 4 2 1 8 6 5 4 5];
counts=histc(A',1:max(A(:))+1)'
counts = 7×10
1 3 2 0 3 0 0 0 1 0 2 2 2 1 0 1 1 1 0 0 3 1 1 3 0 1 0 1 0 0 3 2 1 1 0 1 1 0 1 0 4 3 1 0 0 1 0 0 1 0 3 2 1 1 2 0 1 0 0 0 3 1 0 2 2 1 0 1 0 0
  1 Comment
PEDRO ALEXANDRE Fernandes
Fantastic. Works to perfection. I had already thought of this solution but I was missing something. Thank you very much

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More Answers (2)

KSSV
KSSV on 5 Mar 2022
A = [ 9 5 2 1 5 3 3];
x = unique(A);
N = numel(x);
count = zeros(N,1);
for k = 1:N
count(k) = sum(A==x(k));
end
disp([ x(:) count ]);
1 1 2 1 3 2 5 2 9 1

Matt J
Matt J on 5 Mar 2022
Edited: Matt J on 5 Mar 2022
A = [ 9 5 2 1 5 3 3 2 2 5
1 8 3 1 7 4 3 2 2 6
1 3 1 1 8 6 4 4 2 4
1 3 1 6 4 2 1 2 9 7
2 1 6 3 2 2 1 1 9 1
2 3 1 1 7 5 4 2 1 5
1 1 4 2 1 8 6 5 4 5];
B=A==reshape(0:9,1,1,[]);
numRepetitions=sum(sum(B,2)>1,3)
numRepetitions = 7×1
3 3 2 2 2 3 3

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