% Spline interpolation simple wavelet
% splinewavelet.m L Braile 3/7/2005
x = [0 1  3   4    5  6.2 8.3 9.6 12];
y = [0 0 2.8 0.5 -2.7  0   1   0   0];
minx = min(x);
maxx = max(x);
dx = 0.05;
xs = [minx:dx:maxx]; % interpolate with delta x = 0.05
% x values are now evenly spaced
%
% choose nearest, linear, spline or cubic options
%ys = interp1(x,y,xs,'nearest');
%ys = interp1(x,y,xs,'cubic');
%ys = interp1(x,y,xs,'linear');
ys = interp1(x,y,xs,'spline');
plot(x,y,'-b',x,y,'ob')
hold on
plot(xs,ys,'-r','linewidth',3)
xlabel('x')
ylabel('y')
title('Spline interpolation for simple wavelet')
hold off