MATLAB: Detecting no. of events

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I have an array of 2000×1 = D .

i have a condition D>25. for D>25 higher than 20 sec i should count 1 event.

how can i do this in matlab?

Best Answer

If D contains an entry every second, you can use:

 D = randi(2000, 1, 20); % sample data
 di = diff([0 D > 25 0]);
 i1 = find(di == 1);
 i2 = find(di == -1);
 Nevents = nnz(i2 - i1 > 20);

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ffty = fft(y);
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MATLAB: Which image is not like the others

Compute difference of two images using "imabsdiff()" function, output of this function would be a matrix if both images are same, resulting matrix would have all zeros, you can use this logic.

for example:-

diff1 = imabsdiff(I1, I2);

diff2 = imabsdiff(I2, I3);

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if sum(sum(diff1)) == 0 && sum(sum(diff2)) == 0 && sum(sum(diff3)) ~= 0 && sum(sum(diff4)) ~= 0

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elseif sum(sum(diff1)) ~= 0 && sum(sum(diff2)) ~= 0 && sum(sum(diff3)) == 0 && sum(sum(diff4)) == 0

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elseif sum(sum(diff1)) ~= 0 && sum(sum(diff2)) == 0 && sum(sum(diff3)) == 0 && sum(sum(diff4)) ~= 0

diff = I1;

end

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MATLAB: Which image is not like the others

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