MATLAB: Extracting data from an array

Question

Hello guys,

I've a (14×3) array from which I need to extract data and save in two separate arrays.

I only need the data when in column 2, the value changes from 0 to 1 and back to 0. The data has to be extracted from 0 to 0. There are two sets of such occurrences and I need to save these in two separate arrays. Could you please help me solve this?

Thanks in advance Kind Regards Hari

Answer 1

As Azzi mentions, it is not perfectly clear what you want as your output, but here is my best guess at the code you need:

A = [1 0 0.1
     2 0 0.3
     3 1 0.7
     4 2 0.4
     5 2 0.7
     6 1 0.8
     7 0 0.3
     8 0 0.7
     9 0 0.4
    10 1 0.7
    11 2 0.5
    12 2 0.1
    13 1 0.8
    14 0 0.2];
zeroIndices = find(A(:,2)==0);
numberZeros = numel(zeroIndices);
cellNumber = 0;
for nz = 1:numberZeros-1;
    if zeroIndices(nz+1) > zeroIndices(nz)+1
        cellNumber = cellNumber + 1;
        C{cellNumber} = A(zeroIndices(nz):zeroIndices(nz+1),:);
    end
end

Since you said you want "0 to 0", I included those rows. If you really only wanted the non-zero rows, use this instead:

C{cellNumber} = A(zeroIndices(nz)+1:zeroIndices(nz+1)-1,:);