Search indecies in matrix

thank you very much

Answer 1

[the cyclist]

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) = [];

Answer 2

[bob k]

Hi 'the cyclist',

Thank you very much, I could not figure that out for the life of me. I really appreciate it.

[the cyclist]

I'm happy to have helped!

Two quick comments:

1. The best form of thanks is upvoting and/or accepting the solution, which rewards the person who answered, and also may help guide folks who may have similar questions.
2. You added this remark as a new "answer", when it would have been better placed as a comment on my answer.