>>> """
==========
Wind Barbs
==========

Demonstration of wind barb plots.
"""
... import matplotlib.pyplot as plt
... import numpy as np
... 
... x = np.linspace(-5, 5, 5)
... X, Y = np.meshgrid(x, x)
... U, V = 12 * X, 12 * Y
... 
... data = [(-1.5, .5, -6, -6),
...         (1, -1, -46, 46),
...         (-3, -1, 11, -11),
...         (1, 1.5, 80, 80),
...         (0.5, 0.25, 25, 15),
...         (-1.5, -0.5, -5, 40)]
... 
... data = np.array(data, dtype=[('x', np.float32), ('y', np.float32),
...                              ('u', np.float32), ('v', np.float32)])
... 
... fig1, axs1 = plt.subplots(nrows=2, ncols=2)
... # Default parameters, uniform grid
... axs1[0, 0].barbs(X, Y, U, V)
... 
... # Arbitrary set of vectors, make them longer and change the pivot point
... # (point around which they're rotated) to be the middle
... axs1[0, 1].barbs(
...     data['x'], data['y'], data['u'], data['v'], length=8, pivot='middle')
... 
... # Showing colormapping with uniform grid.  Fill the circle for an empty barb,
... # don't round the values, and change some of the size parameters
... axs1[1, 0].barbs(
...     X, Y, U, V, np.sqrt(U ** 2 + V ** 2), fill_empty=True, rounding=False,
...     sizes=dict(emptybarb=0.25, spacing=0.2, height=0.3))
... 
... # Change colors as well as the increments for parts of the barbs
... axs1[1, 1].barbs(data['x'], data['y'], data['u'], data['v'], flagcolor='r',
...                  barbcolor=['b', 'g'], flip_barb=True,
...                  barb_increments=dict(half=10, full=20, flag=100))
... 
... # Masked arrays are also supported
... masked_u = np.ma.masked_array(data['u'])
... masked_u[4] = 1000  # Bad value that should not be plotted when masked
... masked_u[4] = np.ma.masked
... 
... #############################################################################
... # Identical plot to panel 2 in the first figure, but with the point at
... # (0.5, 0.25) missing (masked)
... fig2, ax2 = plt.subplots()
... ax2.barbs(data['x'], data['y'], masked_u, data['v'], length=8, pivot='middle')
... 
... plt.show()
... 
... #############################################################################
... #
... # .. admonition:: References
... #
... #    The use of the following functions, methods, classes and modules is shown
... #    in this example:
... #
... #    - `matplotlib.axes.Axes.barbs` / `matplotlib.pyplot.barbs`
...