www.gusucode.com > mbcmodels 工具箱 matlab 源码程序 > mbcmodels/@localtruncps/diff.m
function q=diff(p,m); % TRUNCPS/DIFF Differentiate polynomial % Copyright 2000-2004 The MathWorks, Inc. and Ford Global Technologies, Inc. q=p; c=double(q)'; if nargin<2 m=1; end beta= double(p.xreglinear); poly= polynom(p); poly= diff(poly,m); n= length(beta)-length(p.knots)+1; for i=1:m beta(n:end) = beta(n:end)*(p.order-1); p.order=p.order-1; end beta= [double(poly);beta(n:end)]; p.xreglinear=update(p.xreglinear,beta); q= p;