akaike.m

这是一个用于语音信号处理的工具箱

function [a,b,sig2,iflag] = akaike(x,n,a0,b0,ip,iq,nit,epsilon,per) 
      
sig2p = var_my(x,n,ip,iq,a0,b0);
for i=1:ip 
   a(i)=a0(i);
end
for i=1:iq 
   b(i)=b0(i);
end
for k=1:nit 
   y = polefilt(x,n,iq,b);
   y1 = polefilt(y,n,iq,b);
   z = zerofilt(y1,n,ip,a);
	[ry rz ryz rzy] = corrcomp(n,y,z,ip,iq);
   g = grad(a,b,ip,iq,ry,rz);
   h = hess_my(ip,iq,ry,rz,ryz,rzy);
   bv = bvect(a,b,ip,iq,g,h);
   l=0;
   for j=1:ip+iq 
      bvc(j)=bv(j);
      for i=1:j 
         l=l+1;
         hc(l)=h(i,j);
      end
   end
   m=ip+iq;
   [iflag bvc] = cholesky(hc,bvc,m,epsilon);
   if iflag == -1
      return;
   end
   iflag=3;
   for i=1:iq 
      bc(i)=bvc(ip+i);
   end
   if iq == 1
      bbc(1,1)=bc(1);
   end
   pma=1;
   if iq > 1
		[bbc p0 p] = stepdown(iq,bc,pma);
   end
   for i=1:iq 
      if abs(bbc(i,i)) >= 1.0
         iflag=1;
         return;
      end
   end
   for i=1:ip 
      a(i)=real(bvc(i));
   end
   for i=1:iq 
      b(i)=real(bvc(i+ip));
   end
   [sig2 iflag] = chkdn(sig2p,n,x,a,b,ip,iq,per);
   if isempty(iflag) == 1
      return;
   end
   if k >= nit 
      iflag=2;
      return;
	end
   sig2p=sig2;
end