MATLAB: Search indecies in matrix

Question

thank you very much

Answer 1

l1 =  {'A' 'B';
          'B' 'A';
          'B' 'C';
          'C' 'D';
          'D' 'E';
          'E' 'F';
          'F' 'E';
          'F' 'C';
          'C' 'F';
          'F' 'B';
          'B' 'F';
          'F' 'G';
          'G' 'F';
          'G' 'A';
          'G' 'E';
          'E' 'G'};
x = {'B' 'C' 'D' 'E' 'F' 'G'};
numberRows = size(l1,1);
numberCols = size(x,2) + 1; % Offsetting by one, to compensate for the 0 values in loc. Will chop that off later.
[~,loc] = ismember(l1,x);
loc1 = loc(:,1)+1;
loc2 = loc(:,2)+1;
A = zeros(numberRows,numberCols);
linearIndex1 = sub2ind(size(A),1:numberRows,loc1');
linearIndex2 = sub2ind(size(A),1:numberRows,loc2');
A(linearIndex1) = -1;
A(linearIndex2) =  1;
% Chop off spurious first column
A(:,1) = [];