"""

=================

barbs(X, Y, U, V)

=================

See `~matplotlib.axes.Axes.barbs`.

"""

import matplotlib.pyplot as plt

import numpy as np

plt.style.use('_mpl-gallery-nogrid')

# make data:

X, Y = np.meshgrid([1, 2, 3, 4], [1, 2, 3, 4])

angle = np.pi / 180 * np.array([[15., 30, 35, 45],

[25., 40, 55, 60],

[35., 50, 65, 75],

[45., 60, 75, 90]])

amplitude = np.array([[5, 10, 25, 50],

[10, 15, 30, 60],

[15, 26, 50, 70],

[20, 45, 80, 100]])

U = amplitude * np.sin(angle)

V = amplitude * np.cos(angle)

# plot:

fig, ax = plt.subplots()

ax.barbs(X, Y, U, V, barbcolor='C0', flagcolor='C0', length=7, linewidth=1.5)

ax.set(xlim=(0, 4.5), ylim=(0, 4.5))

plt.show()