load X.mat
lonlat = [];
lonlat(:,1) = X(:, 1);
lonlat(:,2) = X(:, 2);
speed = X(:, 3);

figure
plot(lonlat(:, 1), lonlat(:, 2), 'r', 'LineWidth', 2);
% Put a begin and end marker
line(lonlat(1, 1), lonlat(1, 2), 'Marker', 'o', ...
    'Color', 'b', 'MarkerFaceColor', 'b', 'MarkerSize', 10);
line(lonlat(end, 1), lonlat(end, 2), 'Marker', 's', ...
     'Color', 'b', 'MarkerFaceColor', 'b', 'MarkerSize', 10);
hold on
plot3(lonlat(:,1),lonlat(:,2), speed);
plot_google_map('maptype', 'roadmap');