Test different number(values or label) in matrix?

Question

REN 2011-3-3

0
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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2462-test-different-number-values-or-label-in-matrix

hello, I want to detect different number in matrix?

for exmaple in a matrix:

0 0 0 0 0 0; 
3 0 0 0 0 0; 
3 3 0 0 0 0;
0 0 0 4 4 4; 
0 5 5 0 0 0;
5 5 5 5 0 0;

How can I know the number of different values in this matrix, and index for any elements with same value?

Can I use function 'diff'?

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Answer 1

Paulo Silva 2011-3-3

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https://ww2.mathworks.cn/matlabcentral/answers/2462-test-different-number-values-or-label-in-matrix#answer_3853

在 MATLAB Online 中打开

number of different values, A is your matrix

numel(unique(A))

All code:

a=[0 0 0 0 0 0 0 
3 3 0 0 0 0 0 
3 3 3 0 0 0 0
0 0 0 0 4 4 4 
0 0 5 5 0 0 0
5 5 5 5 5 0 0];
b=unique(a)
for i=2:numel(b)
c=find(a==b(i))';
fprintf('The value %d appears %d times, indices %s\n',b(i),numel(c),num2str(c))
end

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REN 2011-3-3

thanks...

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Answer 2

Matt Fig 2011-3-3

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链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2462-test-different-number-values-or-label-in-matrix#answer_3854

在 MATLAB Online 中打开

A = [0 0 0 0 0 0 0; 
     3 3 0 0 0 0 0; 
     3 3 3 0 0 0 0;
     0 0 0 0 4 4 4; 
     0 0 5 5 0 0 0;
     5 5 5 5 5 0 0]
U = unique(A);  % Has the unique elements of A.
LU = length(U);  % Has the number of unique elements of A.
[L,I] = histc(A(:).',U) % Has the counts per element and locations.