# ↑のリンクからお借りした

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(-3, 3, 101)
y1 = np.sin(x * np.pi)
y2 = np.cos(x * 2 * np.pi) * 0.5

fig = plt.figure()
ax = fig.add_subplot(111)

# labelオプションで凡例に用いる曲線名を指定
ax.plot(x, y1, c="r", label="$\mathrm{sin}(x)$")
ax.plot(x, y2, c="b", label="$0.5 \mathrm{cos}(2x)$")
ax.grid(axis='both')

# 凡例の表示
ax.legend()

import matplotlib.pyplot as plt
import matplotlib.collections as mcol
from matplotlib.legend_handler import HandlerLineCollection, HandlerTuple
from matplotlib.lines import Line2D
import numpy as np

t1 = np.arange(0.0, 2.0, 0.1)
t2 = np.arange(0.0, 2.0, 0.01)

fig, ax = plt.subplots()

# note that plot returns a list of lines. The "l1, = plot" usage
# extracts the first element of the list into l1 using tuple
# unpacking. So l1 is a Line2D instance, not a sequence of lines
l1, = ax.plot(t2, np.exp(-t2))
l2, l3 = ax.plot(t2, np.sin(2 * np.pi * t2), '--o', t1, np.log(1 + t1), '.')
l4, = ax.plot(t2, np.exp(-t2) * np.sin(2 * np.pi * t2), 's-.')

ax.legend((l2, l4), ('oscillatory', 'damped'), loc='upper right', shadow=True)
ax.set_xlabel('time')
ax.set_ylabel('volts')
ax.set_title('Damped oscillation')
plt.show()

plot = Plot(lho, llo, figsize=(12, 6), sharex=True, yscale='log')
ax1, ax2 = plot.axes
for ifo, ax in zip(('Hanford', 'Livingston'), (ax1, ax2)):
ax.legend(['X', 'Y', 'Z'])
ax.text(1.01, 0.5, ifo, ha='left', va='center', transform=ax.transAxes,
fontsize=18)
ax1.set_ylabel(r'$1-3$\,Hz motion [nm/s]', y=-0.1)
ax2.set_ylabel('')
ax1.set_title('Magnitude 7.1 earthquake impact on LIGO')
plot.show()

plot = Plot(data1, data2, data3)
ax = plot.gca()
ax.legend(['data1dayo', 'data2 dayo', 'data3 dayo''])
plot.show()