I have created code for banded gauss elimination method but on running it gives an error of index exceeds matrix dimensions

Question

Haseeb Ahmed Janjua 2017-10-20

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/362254-i-have-created-code-for-banded-gauss-elimination-method-but-on-running-it-gives-an-error-of-index-ex

回答： Martin Olafsen 2017-10-20

function x = gauss_elimination(K,M);
ln = length(M); x = zeros(ln,1);
for n=1:ln-1
        for i=n+1:ln
             m = K(i,n)/K(n,n);
             for j=n+1:ln
               K(i,j) = K(i,j)-m*K(n,j);
             end
             M(i) = M(i)-m*M(n);
        end
  end
  x(ln) = M(ln)/K(ln,ln);
  for i=ln-1:-1:1
     S = M(i);
     for j=i+1:ln
       S = S-K(i,j)*x(j);
     end
     x(i) = S/K(i,i);
  end
  end
  %%another function created to call gauss elimination function in it
  clc
  clear 
%Two additional matrices A and B were added for checking the gauss elimination
%function:
A= [ 170.4105 37.9473 -113.8420 -37.9473;
    37.9473 69.2176 -37.9473 -12.6491;
    -113.8420 -37.9473 120.9131 45.0184;
    -37.9473 -12.6491 45.0184 19.7202];
B = [0; 0; 0; -1000];
K = xlsread('HW05_Coef.xlsx');
M = csvread('HW05_Const.csv');
gauss_elimination(K,M)