MATLAB实现追赶法

function [ x ] = Chase_method( A, b )
%Chase method 追赶法求三对角矩阵的解
%   A为三对角矩阵的系数，b为等式右端的常数项，返回值x即为最终的解
%   注：A尽量为方阵，b一定要为列向量
%% 求追赶法所需L及U
T = A;
for i = 2 : size(T,1)T(i,i-1) = T(i,i-1)/T(i-1,i-1);T(i,i) = T(i,i) - T(i-1,i) * T(i,i-1);
end
L = zeros(size(T));
L(logical(eye(size(T)))) = 1;   %对角线赋值1
for i = 2:size(T,1)for j = i-1:size(T,1)L(i,j) = T(i,j);break;end
end
U = zeros(size(T));
U(logical(eye(size(T)))) = T(logical(eye(size(T))));
for i = 1:size(T,1)for j = i+1:size(T,1)U(i,j) = T(i,j);break;end
end
%% 利用matlab解矩阵方程的遍历直接求解
y = L\b;
x = U\y;
end