判断并将矩阵转化为严格对角占优矩阵

% Judge is a matrix is a strict diagonal dominance matrix% and Transform the matrix into a strict diagonal dominance matrix% input:%   A: the original matrix% output:%   X: the strict diagonal dominance matrix that we transform%   t: the time that the transform process takesfunction [X t]= StrictDiagMatrix(A)tic%  if the matrix is not a squre matrix,return error if size(A, 1) ~= size(A, 2)        error('It is not a square matrix'); end% get the size of the matrix and initial a matrix X to store the output matrix  n = size(A,1);  X = zeros(n,n);% the record array is used to accord if all the row be set  record = zeros(n);  for i = 1 : n;% get the absolute value of every element in every row    row_max = abs(A(i,:));% find out the max element of the row,and use pos to accord its position in    [max_ele,pos] = max(row_max);% check if the max_ele is the realy max element of the row,if not,return error    if max_ele <= sum(abs(A(i,:))) - max_ele        error('The matrix can not be transformed into a strictly diagonally dominant matrix');    end% set the row pos of matrix X with A(i,:)% accord this row has been set            X(pos,:) = A(i,:);            record(pos) = 1;  end% if there exits any row that has not been set,return error  if sum(record) ~= n      error('The matrix can not be transformed into a strictly diagonally dominant matrix');  end% output the time it take and output success   fprintf('The oringinal matrix input is:\n');  disp(A);  fprintf('The time it cost is:   ')  t = toc;  disp(t);  fprintf('It can be transformed to a strictly diagonally dominant matrix: \n');end