Error bar rendering on polar axis

Demo of error bar plot in polar coordinates. Theta error bars are curved lines ended with caps oriented towards the center. Radius error bars are straight lines oriented towards center with perpendicular caps.

import matplotlib.pyplot as plt
import numpy as np

theta = np.arange(0, 2 * np.pi, np.pi / 4)
r = theta / np.pi / 2 + 0.5

fig = plt.figure(figsize=(10, 10))
ax = fig.add_subplot(projection='polar')
ax.errorbar(theta, r, xerr=0.25, yerr=0.1, capsize=7, fmt="o", c="seagreen")
ax.set_title("Pretty polar error bars")
plt.show()