exm040209.m

matlab电子书籍

randn('state',0);
A=gallery('randsvd',300,2e13,2);	
x=ones(300,1);				
b=A*x;							
cond(A)	

tic								
xi=inv(A)*b;					
ti=toc							
eri=norm(x-xi)				
rei=norm(A*xi-b)/norm(b)	

tic;
xd=A\b;			
td=toc
erd=norm(x-xd)
red=norm(A*xd-b)/norm(b)