from lets_plot import *

def_min_exp, def_max_exp = -7, 7
values = [3.14 * 10**d for d in range(def_min_exp, def_max_exp)]

def plot(f=None):
    t = layer_tooltips().line("@v")
    if f is not None:
        t = t.format("@v", f)
    return ggplot({'v': values}, aes(y='v')) + \
        geom_point(x=0, tooltips=t) + \
        geom_text(aes(label='v'), x=1, label_format=f) + \
        scale_x_continuous(limits=[-.5, 2]) + \
        scale_y_log10(limits=[10**def_min_exp, 10**def_max_exp], format=f) + \
        ggsize(400, 600) + \
        ggtitle("Default format" if f is None else 'format="{0}"'.format(f))