今天擦完了玻璃，盡管有地方不那麽明亮幹凈，冷風中瑟瑟發抖，年也快臨近了。

代碼是從網上找的，

function [p, np, r, nr] = deconv_m(b, nb, a, na)
	% Modified deconvolution routine for noncausal sequences
	% ----------------------------------------------------
	% function [p, np, r, nr] = deconv_m(b, nb, a, na)
	% 
	%   p = polynomial part of support np1 <=n <= np2
	%  np = [np1, np2] 
	%   r = remainder part of support nr1 <= n <= nr2 
	%  nr = [nr1, nr2]
	%   b = numerator palynomial of support nb1 <= n <= nb2
	%  nb = [nb1, nb2]
	%   a = denominal polynomial of support na1 <= n <= na2
	%  na = [na1, na2]
	%
npb = nb(1)-na(1); npe = nb(length(b)) - na(length(a));
 np = [npb:npe];
 nr = nb;

[p, r] = deconv(b, a);

　　運行代碼如下：

%% ----------------------------------------------------------------------------
%%            Output Info about this m-file
fprintf(‘\n***********************************************************\n‘);
fprintf(‘        <DSP using MATLAB> Problem 4.10 \n\n‘);

banner();
%% ----------------------------------------------------------------------------


%% -------------------------------------------------
%%            1      X(z)
%% -------------------------------------------------

b = [1, 1, 1, 1, 1, 1]; nb = [-2:3]; 
a = [1, 2, 1];          na = [-1:1];                 

%[p, r] = deconv(b, a)
[p, np, r, nr] = deconv_m(b, nb, a, na)
 

　　運行結果：

《DSP using MATLAB》Problem 4.10