from cycler import cycler
import matplotlib as mpl
import matplotlib.pyplot as plt
import numpy as np
mpl.__version__  # ==1.5.1

linestyle_cycle = cycler('linestyle', ['-', '--'])
ls_cycle = cycler('ls', ['-', '--'])

x = np.arange(10)

mpl.rcParams['axes.prop_cycle'] = linestyle_cycle
plt.figure()
for k in range(1, 6):
    plt.plot(x, k * x)
plt.plot(x, x**2, 'k:')  # Black dotted as expected
plt.title('linestyle_cycle')

mpl.rcParams['axes.prop_cycle'] = ls_cycle
plt.figure()
for k in range(1, 6):
    plt.plot(x, k * x)
plt.plot(x, x**2, 'k:')  # Black dashed - not expected
plt.title('ls_cycle')