%?Gauss消去法：順序高斯消去
%?A為系數矩陣，n*n
%?b為右端項，n維向量
clear
clc
%%%輸入矩陣
%q1=6*ones（201）‘;?%對角線元素
%q2=ones（191）‘;?%對角線上方的元素，個數比A少一個
%q3=8*ones（191）‘;?%對角線下方的元素，個數比A少一個
%A=diag（q1）+diag（q21）+diag（q3-1）
A=[6?1?1?1?1?1?1?1?1?1;
???8?6?1?1?1?1?1?1?1?1;
???1?8?6?1?1?1?1?1?1?1;
???1?1?8?6?1?1?1?1?1?1;
???1?1?1?8?6?1?1?1?1?1;
???1?1?1?1?8?6?1?1?1?1;
???1?1?1?1?1?8?6?1?1?1;
???1?1?1?1?1?1?8?6?1?1;
???1?1?1?1?1?1?1?8?6?1;
???1?1?1?1?1?1?1?1?8?6];
%b=15*ones（101）;
%b（1）=7;
%b（20）=14;
b=[7?15?15?15?15?15?15?15?15?1