funm.m

高等引用数学的matlab求解的配套程序

   function F=funm(A,fun,x)
   [V,J]=jordan(A); v1=[0,diag(J,1)'];
   v2=[find(v1==0), length(v1)+1];
   for i=1:length(v2)-1
       v_lambda(i)=J(v2(i),v2(i)); v_n(i)=v2(i+1)-v2(i); 
   end
   m=length(v_lambda); 
   F=sym([]);
   for i=1:m
       J1=J(v2(i):v2(i)+v_n(i)-1,v2(i):v2(i)+v_n(i)-1);
       fJ=funJ(J1,fun,x); F=diagm(F,fJ);
   end    
   F=V*F*inv(V);
   
function A=diagm(A1,A2)
A=A1; 
A(size(A1,1)+1:size(A1,1)+size(A2,1),size(A1,2)+1:size(A1,2)+size(A2,2))=A2;
   
function fJ=funJ(J,fun,x)
lam=J(1,1); f1=fun;
fJ=subs(fun,x,lam)*eye(size(J));
H=diag(diag(J,1),1); H1=H;
for i=2:length(J)
   f1=diff(f1,x); a1=subs(f1,x,lam);
   fJ=fJ+a1*H1; H1=H1*H/i;
end