www.gusucode.com > mbcmodels 工具箱 matlab 源码程序 > mbcmodels/@localpspline/NestedJacobian.m
function [X,dJ]= NestedJacobian(ps,x,k); % POLYSPLINE/X2FX generates X matrix for regression % Copyright 2000-2004 The MathWorks, Inc. and Ford Global Technologies, Inc. % Make X = [1 (x(x<=k)-k).^2 0 ] % [1 0 (x(x>k)-k).^2 ] % allow for the case where one is empty and % then make spline symmetric ps.knot= k; X= zeros(length(x),sum(ps.order)-1); dJ= X; X(:,1)=1; m = (x > ps.knot) ; xk= x-ps.knot; for i=2:ps.order(1) % rhs X(:,i)= xk.^i; dJ(:,i)= -xk.^(i-1); end X(~m,2:ps.order(1))=0; dJ(~m,2:ps.order(1))=0; i=i-1; for j=2:ps.order(2) % lhs X(:,i+j)= xk.^j; dJ(:,i+j)= -xk.^(j-1); end X(m,i+2:ps.order(2)+i)=0; dJ(m,i+2:ps.order(2)+i)=0;