def compass_url(points, width=500, height=500):
legend = lambda p: map(lambda x: x[0], p)
data_x = lambda p: map(lambda x: float(x[1]), p)
data_y = lambda p: map(lambda x: float(x[2]), p)
chart = ScatterChart(width, height, x_range=(-10, 10), y_range=(-10, 10))
chart.add_data(data_x(points))
chart.add_data(data_y(points))
chart.set_legend(legend(points))
chart.set_legend_position('b')
chart.set_grid(5, 5, 5, 3)
chart.set_colours_within_series(colors(points))
axis = (chart.set_axis_labels(Axis.LEFT, ['Left']),
chart.set_axis_labels(Axis.RIGHT, ['Right']),
chart.set_axis_labels(Axis.TOP, ['Authoritarian']),
chart.set_axis_labels(Axis.BOTTOM, ['Libertarian']))
for a in axis:
chart.set_axis_positions(a, [50])
chart.set_axis_style(a, '000000', '15')
url_bits = ['%s,%s' % (a, '-180') for a in axis]
url = chart.get_url()
url = url + '&chxtc=' + '|'.join(url_bits)
return url
