mathanalysis201.m

来自「数值分析的实验程序」· M 代码 · 共 29 行

format long
A=[1e-8 2 3
    -1 3.712 4.623
    -2 1.072 5.643];
b=[1 2 3]';
%A=[1 -1 1
%   -3 1 -2
 %  3 1 -1];
%b=[2 6 12]';
A=[A b];
[m,n]=size(A);
x=zeros(m,1);
for i=2:m
    for j=i:m
            A(j,:)=A(j,:)/A(j,i-1)*A(i-1,i-1);
    end
    for j=i:m
        A(j,:)=A(j,:)-A(i-1,:);
    end
end
b=A(1:m,n);
A=A(1:m,1:m);
x(m)=b(m)/A(m,m);
for k=m-1:-1:1
        x(k)=(b(k)-A(k,:)*x)/A(k,k);
end
printx=['The matrix of x is ',mat2str(x),'.'];
disp(printx);