Extending a plot outside of axes

Community matplotlib-users
1

Hi all.

is it not possible to extend plot outside of a plot area? To illustrate what I want
to do take for example the wind barbs example from the matplotlib gallery.
(see below)

I only changed line 23 from ax.barbs(X, Y, U, V) to ax.barbs(X, Y, -U, -V)

But now we don't see the tail of the barbs in the first subplot.

So Is it possible to let matplotlib plot the tail, without extending the axes?

Best Regards
Einar M. Einarsson

'''
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)])

#Default parameters, uniform grid
ax = plt.subplot(2,2,1)
ax.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
ax = plt.subplot(2,2,2)
ax.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
ax = plt.subplot(2,2,3)
ax.barbs(X, Y, U, V, np.sqrt(U*U + V*V), 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
ax = plt.subplot(2,2,4)
ax.barbs(data['x'], data['y'], data['u'], data['v'], flagcolor='r',
     barbcolor=['b','g'], barb_increments=dict(half=10, full=20, flag=100),
     flip_barb=True)

plt.show()

2

Einar M. Einarsson wrote:

Hi all.

is it not possible to extend plot outside of a plot area? To illustrate what I want
to do take for example the wind barbs example from the matplotlib gallery.
(see below)

I only changed line 23 from ax.barbs(X, Y, U, V) to ax.barbs(X, Y, - U, -V)

But now we don't see the tail of the barbs in the first subplot.

So Is it possible to let matplotlib plot the tail, without extending the axes?
  
Einar: You can use the set_clip_box method of the barbs instance to turn clipping off:

bb = ax.barbs(X, Y, -U, -V)
bb.set_clip_box(None)

-Jeff

···

Best Regards
Einar M. Einarsson

'''
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)])

#Default parameters, uniform grid
ax = plt.subplot(2,2,1)
ax.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
ax = plt.subplot(2,2,2)
ax.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
ax = plt.subplot(2,2,3)
ax.barbs(X, Y, U, V, np.sqrt(U*U + V*V), 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
ax = plt.subplot(2,2,4)
ax.barbs(data['x'], data['y'], data['u'], data['v'], flagcolor='r',
     barbcolor=['b','g'], barb_increments=dict(half=10, full=20, flag=100),
     flip_barb=True)

plt.show()