How to return logical array with only the longest row-consecutive equal to true

How to take logical array of rows and columns and return the same size logical array but all values beside the location of the longest row-consecutive true values are false. If multiple rows have the same larget consecutive true values, then the first row with the largest consecutive true values is returned. I have working code but I'd like to vectorize it as it currently is loop-based and takes longer than I'd like. Oh and most logical array inputs have between 1 and 50 rows, and the number of columns are greater than 200,000.

i.e.

input =  [0 0 0 1 1 1 1 0 0 1 1 0;
          1 1 1 0 0 1 0 0 1 1 1 1;
          0 1 0 1 0 1 1 1 1 1 1 1];

output = [0 0 0 0 0 0 0 0 0 0 0 0;
          0 0 0 0 0 0 0 0 0 0 0 0
          0 0 0 0 0 1 1 1 1 1 1 1];

input =  [0 0 1 1 1 1 1 1 0 0 0 0;
          0 0 1 0 0 1 0 0 1 0 0 1;
          1 1 1 1 1 1 0 0 0 0 0 0];

output = [0 0 1 1 1 1 1 1 0 0 0 0;
          0 0 0 0 0 0 0 0 0 0 0 0;
          0 0 0 0 0 0 0 0 0 0 0 0];

Thank you so much!

Answer 1

[David Hill]

I =  [0 0 1 1 1 1 1 1 0 0 0 0;
      0 0 1 0 0 1 0 0 1 0 0 1;
      1 1 1 1 1 1 0 0 0 0 0 0];
i=[zeros(size(I,1),1),I,zeros(size(I,1),1)];
d=diff(i,1,2);
[r,c]=find(d==1);
[R,C]=find(d==-1);
[r,idx]=sort(r);c=c(idx);
[R,idx]=sort(R);C=C(idx);
[~,idx]=max(C-c);
O=zeros(size(I));
O(r(idx),c(idx)+1:C(idx))=1

O = 3×12

0 0 0 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

[Ryan]

That works great. Thank you!