数值分析第07次作业(4)

n=length(b);

u0=0;y0=0;a(1)=-1; L(1)=b(1)-a(1)*u0;

y(1)=(d(1)-y0*a(1))/L(1); u(1)=c(1)/L(1); for i=2:(n-1)

L(i)=b(i)-a(i)*u(i-1);

y(i)=(d(i)-y(i-1)*a(i))/L(i); u(i)=c(i)/L(i); end

L(n)=b(n)-a(n)*u(n-1);

y(n)=(d(n)-y(n-1)*a(n))/L(n); x(n)=y(n); for i=(n-1):-1:1

x(i)=y(i)-u(i)*x(i+1); end x

运行结果： >> x =

Columns 1 through 6

2.0000 1.0000 -3.0000

Columns 7 through 10

3.0000 -0.0000 1.0000

0.0000 1.0000 -1.0000 -2.0000