load linefit.dat;
x = linefit(:,1);
y = linefit(:,2);
xp = linspace(0,7,100);
n = length(x) - 1;
% Create n_th order polynomial through data:
pcoeffn = polyfit(x,y,n);
ypn = polyval(pcoeffn,xp);
figure(1), plot(x,y,'o',xp,ypn,'m')
% Create LINEAR spline through the data:
yint = interp1(x,y,xp);
figure(5), plot(x,y,'o',xp,yint,'m');
% Create cubic spline through data:
yspline = spline(x,y,xp);
figure(6), plot(x,y,'o',xp,yspline,'m')