matlab软件

clc;clear
x=[2002 2003 2004 2005 2006 2007 ]
y=[6.7 16.8 97 397 1294.4 2796 ]
x1=2002:0.1:2007;
y1=log(y)
p=polyfit(x,y1,2)
ff=vpa(poly2sym(p,'x'),5)
figure(1)
plot(x,y1,'o',x1,polyval(p,x1))
%f=inline('exp(x.^4*a(1)+x.^3*a(2)+x.^2*a(3)+x*a(4)+a(5))','a','x')
f=inline('exp(a(1)*x.^2+a(2)*x+a(3))','a','x')
format short g
[a,Res]=nlinfit(x,y,f,p)
xx=2002:0.1:2011;
yy=exp(a(1)*xx.^2+a(2)*xx+a(3));
figure(2)
plot(x,y,'o-',xx,yy)
table=[xx',yy',[y NaN NaN NaN NaN]']

结果：

a =

-0.054134 218.3 -2.2006e+005

Res =

1.7305 -5.2744 9.0073 82.236 283.98 -114.72

table =

2002 4.9695 6.7
2003 22.074 16.8
2004 87.993 97