func9.m

数值分析最常用的四十种算法

x = linspace(0,10,6)
y=[4,2.5,1.5,0.5,-0.5,4.0]
xx = 0:.25:10;
pp=csapi(x,y)        %求三次样条插值多项式,in not-a-knot end condition
yy=ppval(pp,xx)
disp(xx)
plot(x,y,'o',xx,yy)
dp=polyder(pp);             %对拟合多项式p求导数dp
dpx=polyval(dp,x);          %分段多项是难以直接求导！！！！
%x1=5
%y1=ode45(pp,[0,10],0)