xx=[1:1:8]';
yy=[1,0,2,3,1,9,6,0]';
clf
plot(xx,yy,'ro')
A=ones(8,8);
A(:,2)=xx;
A(:,3)=xx.*xx;
A(:,4)=xx.*xx.*xx;
A(:,5)=A(:,4).*xx;
for i=3:8
   A(:,i)=A(:,i-1).*xx;
end
cc=A\yy
xxx=[0.8:0.1:8.4];
yyy=cc(1)+...
   cc(2)*xxx+...
   cc(3)*xxx.^2+...
   cc(4)*xxx.^3+...
   cc(5)*xxx.^4+...
   cc(6)*xxx.^5+...
   cc(7)*xxx.^6+...
   cc(8)*xxx.^7;
hold on
plot(xxx,yyy,'m-')