SS_to_AR.m
上传用户:mozhenmi
上传日期:2008-02-18
资源大小:13k
文件大小:1k
- function [coef, C] = SS_to_AR(F, Q, k, diagonal)
- %
- % Extract the parameters of a vector autoregresssive process of order k from the state-space form.
- % [coef, C] = SS_to_AR(F, Q, k, diagonal)
- if nargin<4, diagonal = 0; end
- s = length(Q) / k;
- bs = s*ones(1,k);
- coef = zeros(s,s,k);
- for i=1:k
- if diagonal
- coef(:,:,i) = diag(diag(F(block(1,bs), block(i,bs))));
- else
- coef(:,:,i) = F(block(1,bs), block(i,bs));
- end
- end
- C = Q(block(1,bs), block(1,bs));
- if diagonal
- C = diag(diag(C));
- end
- %C = sqrt(Q(block(1,bs), block(1,bs))); % since cov(1,1) of full vector = C C'