renumber_ob.m

function m = renumber_ob(m)
    new_node_numbers = [(1:length(m.b))', zeros(length(m.b),1)]; 
    % assume I have only one open ocean boundary 
    new_node_number=1;
    for i = 1 : length(m.op.nbdv(:,1)) % for the nodes on the open boundary
        new_node_numbers(m.op.nbdv(i,1),2) = new_node_number ;
        new_node_number = new_node_number + 1;  
    end
    % now for all other nodes 
    for i = 1 : length(m.p)
        if new_node_numbers(i,2) == 0
           new_node_numbers(i,2) = new_node_number;
           new_node_number = new_node_number + 1; 
        end
    end
    % now update connectivity 
    new_t =m.t;
    for i = 1 : length(m.t) 
       for j = 1: 3
            new_t(i,j) = new_node_numbers(new_t(i,j),2);
       end
    end
    % replace bcs
    m.op.nbdv = new_node_numbers(m.op.nbdv,2);
    for i=1:size(m.bd.nbvv,2)
        col = m.bd.nbvv(:,i);
        col(col>0) = new_node_numbers(col(col>0),2);
        m.bd.nbvv(:,i) = col;
    end
    new_node_numbers = sortrows(new_node_numbers,2);
    m.p = m.p(new_node_numbers(:,1),:);
    m.t = new_t;
    m.b = m.b(new_node_numbers(:,1));