1. function [x,err]=gauss_jordan_elim(A,b)
2. A = [-1 2;3 -4;] % input for augmented matrix A
3. b = [-6; 14;] % intput for matrix B
4. [n,m]=size(A); % finding the size of matrix A
5. err =0; % calculation of error
6. x=zeros(n,1); % calling fuction zero
7. if n ~= m
8.     disp('error: n~=m'); % displaying error if found
9.     err = 1;
10. end % end of the scope of if
11. if length(b) ~= n  % finding the legth of matrix B
12.     disp('error: wrong size of b'); % displaying error, if found
13.     err = 2;
14. else
15.     if size(b,2) ~= 1
16.         b=b';
17.     end % end of the scope of if-else
18.     if size(b,2) ~= 1
19.         disp('error: b is a matrix'); % displaying erron in matrix B
20.         err = 3;
21.     end
22. end
23. if err == 0
24.     Aa=[A,b];
25.     for i=1:n
26.         [Aa(i:n,i:n+1),err]=gauss_pivot(Aa(i:n,i:n+1));
27.         if err == 0
28.             Aa(1:n,i:n+1)=gauss_jordan_step(Aa(1:n,i:n+1),i);
29.         end
30.     end
31.     x=Aa(:,n+1);
32. end
33. A=0;
34. function A1=gauss_jordan_step(A,i) % calling of fuction function
35.  
36. [n,m]=size(A); % determination of size of matrix A
37. A1=A; % assigning A to A1
38. s=A1(i,1);
39. A1(i,:) = A(i,:)/s;
40. k=[[1:i-1],[i+1:n]];
41. for j=k
42.     s=A1(j,1);
43.     A1(j,:)=A1(j,:)-A1(i,:)*s;
44. end % end of for loop
45. function [A1,err]=gauss_pivot(A) % calling of fucntion
46. [n,m]=size(A); % finding the size of matrix A
47. A1=A; % process of assigning
48. err = 0; % error flag
49. if A1(1,1) == 0
50.     check = logical(1); % logical(1) - TRUE
51.     i = 1;
52.     while check
53.         i = i + 1;
54.         if i > n  
55.             disp('error: matrix is singular');
56.             err = 1;
57.             check = logical(0);
58.         else
59.             if A(i,1) ~= 0 & check
60.                 check = logical(0);
61.                 b=A1(i,:);      % process to change row 1 to i
62.                 A1(i,:)=A1(1,:);
63.                 A1(1,:)=b;
64.             end
65.         end
66.     end
67. end