% Script file showing the example in the text

% First, get the data points

numpts=10;

x=linspace(-5,5,numpts)'; %Column vector of data
t=linspace(-5,5,150);  %For plotting

y=1./(1+x.^2); %Column vector of desired output
yt=1./(1+t.^2); %For plotting

V=vander(x);
a=V\y;

%Test the polynomial on the new data in t
yout=polyval(a,t);  %This is to evaluate the polynomial whose coeffs in vector a

plot(x,y,'k*',t,yt,'k-',t,yout,'m-');