You may get linewidth of first line and set it for all other lines of factor plot:
import seaborn as sns
import matplotlib.pylab as plt
sns.set(style="ticks")
exercise = sns.load_dataset("exercise")
g = sns.factorplot(x="time", y="pulse", hue="kind", data=exercise, scale=.5)
lw = g.ax.lines[0].get_linewidth() # lw of first line
plt.setp(g.ax.lines,linewidth=lw) # set lw for all lines of g axes
plt.show()
And you can set line width for every line in a cycle:
for l in g.ax.lines:
print(l.get_linewidth())
plt.setp(l,linewidth=5)
Output:
1.575
3.15
3.15
3.15
1.575
3.15
3.15
3.15
1.575
3.15
3.15
3.15
Bold lines are according to confidential intervals.
After set line width to 5 all lines became the same: