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Hello Help Find Matlab Solution System X B Modify File Gauss Partial Pivoting Gauss Comple Q43877115

Hello, Can you help me to find in MATLAB the solution of thesystem A x= b and then modify my file of gauss partial pivotinginto gauss complete pivoting.

So I’m guessing that I have to use the file of gauss partialpivoting to answer to A x= b but I don’t know what I have to changeto have the right answer.

I have

A =   

-2.1000  -0.5000   -0.9000   -1.9000   1.2000    0.1000

   0.6000            0   -1.9000   2.4000   -1.7000    0.2000

   2.0000   -0.5000            0  -0.2000    0.4000   -0.5000

   2.2000    0.1000  -1.2000    0.4000   0.5000    0.7000

   3.3800    0.6400  -3.4100    4.0800  -1.8900    1.4600

  -0.2300   -0.1900   0.2300    2.6700   -2.7600  -1.1300

   -0.6400-0.1400   -1.0500    0.0200  -0.0200    0.2200

b =   

   -0.8000

  -0.8000

   0.7000

   1.7000

   1.4000

  -2.3600

  -0.4600

I found

x =

    0.6183
         0
    0.3084
   -0.3447
         0
    1.2110

simply with the function x=AB but I can’t compile any goodfunction to find this answer …

And here is the gauss partial pivoting

function x=mygausspivot(A,b)

    if size(A,1) ~= size(A,2)
       error(‘Matrix is notsquare!)’);
    end;
    n=size(A,1);
      
    % Matrix triangualisation:
    for i=1:n
        % Searching for thepivoting line
        % disp([ ‘Treatment ofline i=’ num2str(i) ] );
        n_max=i;
        for m=i:n
           if abs(A(n_max,i)) < abs(A(m,i))
               n_max=m;
           end
        end
   % disp([ ‘Line with pivoting element n_max=’num2str(n_max) ] );
        % exchangement of line iand pivoting line n_max in the matrix A and in the vector b
        for l=i:n
           tmp=A(i,l);
           A(i,l)=A(n_max,l);
           A(n_max,l)=tmp;
        end
        tmp=b(i);
        b(i)=b(n_max);
        b(n_max)=tmp;

        p=A(i,i); % pivotingelement
        % verification ofnon-generation of matrix
        if p==0
           disp(‘Pivoting element is zero (matrix could bedegenerated)!!!’);
           % error(‘Pivoting element is zero (matrix degenerated?)’);
       end     

        for k=i:n
           A(i,k)=A(i,k)/p;
        end
       b(i)=b(i)/p;      
        for j=i+1:n
           r=A(j,i);
           for k=i:n
               A(j,k)=A(j,k)-A(i,k)*r;
           end
           b(j)=b(j)-b(i)*r;
        end
    end
    % In this point our matrix is, normally, uppertriangular
    % (with ones on the diaganonal),
    % and we solving the folowing liniarequation:
    % 1    a_12 …a_1N     x_1      b_1
    % 0    1    …a_2N   * x_2 =   b_2
    % 0    0   ………      .        .
    % 0    0    …1        x_N      b_N
  
    % x calculation from triangular matrix:
    x=b;
    for i=n-1:-1:1
        for k=i+1:n
           x(i)=x(i)-x(k)*A(i,k);
        end
    end

     % now x containes the solution
   
end

Thanks

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Answer to Hello, Can you help me to find in MATLAB the solution of the system A x= b and then modify my file of gauss partial pivo…