function [x0,val,k]=lsnCG(x0,m,n,t)
s=zeros(t,m);
y=zeros(t,m);
kmax=2000;
epsilon=1e-05;
for k=1:kmax
r0=gfun(x0,n); %梯度方向
if norm(r0)<epsilon
break;
end
if k==1
p0=-r0;
elseif k<=m
H0=s(:,k-1)'*y(:,k-1)/(y(:,k-1)'*y(:,k-1))*eye(t,t);
[p0]=LM(r0,s,y,m,H0,k); %方向
p0=-p0;
else
H0=s(:,m)'*y(:,m)/(y(:,m)'*y(:,m))*eye(t,t);
[p0]=LM(r0,s,y,m,H0,k); %方向
p0=-p0;
end
alph=0.5;
rho=1/4;
sigma=0.5;
jmax=200;
f0=fun0(x0,n);
for j=1:jmax % armijo搜索步长
x1=x0+alph*p0;
if (fun0(x1,n)<=f0+sigma*r0'*alph*p0)
break;
else
alph=alph*rho;
end
end
gfun1=gfun(x1,n);
if k<=m
s(:,k)=x1-x0;
y(:,k)=gfun1-r0;
else
for i=1:min(m-1,k-1)
s(:,i)=s(:,i+1);
y(:,i)=y(:,i+1);
end
s(:,m)=x1-x0;
y(:,m)=gfun1-r0;
end
x0=x1;
end
val=fun0(x0,n);
val=double(val);
end
