regarding iteration plot of gauss-seidel method

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aayam goch 2019-1-25

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https://ww2.mathworks.cn/matlabcentral/answers/441402-regarding-iteration-plot-of-gauss-seidel-method

编辑： aayam goch 2019-1-25

I have a Matlab code to find the values of iteratives x and the iterations (k). The code is showing correct answers for the given set of equations and initial values. However I wanted to plot the iteration values on the x-axis (k-1) and iterative solutions on the y-axis (x(i)). However the figure shows blank. Attached is the working matlab code. I needed help in plotting the values and iterations simultaneously.

% source: https://matlabcastor.blogspot.com/search?q=gauss
clc
clear all
close all
  no_eqn=3;
 tolerance=1e-3;
 max_itr=10;
%   tol = input('Enter the tolerance, tol: ');
%  m = input('Enter maximum number of iterations, m:  ');
%  n=input('Enter number of equations, n:  ');
A=[6 -3 1 3;1 2 -1 2; 2 5 -7 -9];
 x1=[0 0 0];
 k = 1;
figure
hold on 
 while  k < max_itr
    err = 0;
    for i = 1 : no_eqn
       s = 0;
       for j = 1 : no_eqn
          s = s-A(i,j)*x1(j);
       end
       s = (s+A(i,no_eqn+1))/A(i,i);
       if abs(s) > err
         err  = abs(s);
       end
       x1(i) = x1(i) + s
    end
    if err <= tolerance
      break;
    else
      k = k+1;
      plot (x(i)),k-1) %%%%% the plot does not show any data in the figure 
    end
    
 end
 fprintf('Solution vector after %d iterations is :\n', k-1)
 
 for i = 1 : no_eqn
   fprintf(' %11.8f \n', x1(i))
 end