clf
axis([0 10 0 10])
hold on

%% Initially, the list of points is empty.
xy = [];
n = 0;

%% Loop, picking up the points.
disp('Left mouse button picks points.')
disp('Right mouse button picks last point.')
but = 1;
while but == 1
    [xi,yi,but] = ginput(1);
    plot(xi,yi,'ro')
    n = n+1;
    xy(:,n) = [xi;yi];
end
[T,ind] = sort(xy(1,:));
Y = xy(2,ind);


%% Interpolate with a spline
% To Do

%% Plot the interpolated curve.
% To Do

hold off