Matplotlib - set pad between arrow and text in annotate function

Question

How do I set the distance (padding) between the arrow and the text in matplotlib's annotate function? Sometimes the text ends up being too close to the arrow and I would like to move them a little further apart.

Basic example:

import matplotlib.pyplot as plt

plt.annotate('Here it is!',xy=(-1,-1),xytext=(0,0),
             arrowprops=dict(arrowstyle='->',lw=1.5))

plt.xlim(-10,10)
plt.ylim(-10,10)

plt.show()

Answer 1

For fancy arrows you can play with the bbox properties:

fig, ax = plt.subplots(1, 3, figsize=(7, 3))
pad_val = [-5, 0, 5]
for a,p in zip(ax, pad_val):
    a.annotate('Here it is!\npad={}'.format(p),xy=(-1,-1),xytext=(1,1),
                arrowprops=dict(arrowstyle='-|>', fc="k", ec="k", lw=1.5),
                bbox=dict(pad=p, facecolor="none", edgecolor="none"))
    a.set_xlim(-10,10)
    a.set_ylim(-10,10)

Here the drawback is that you can't add a color behind the annotation (facecolor="none" is mandatory), or the arrow will always stick to the border of the frame and it might be ugly.

HTH

Answer 2

You can use the shrink keyword argument in your arrowprops dictionary, but unfortunately the FancyArrowPatch object doesn't support it, so you'd have to remove the arrowstyle='->'.

The value given with shrink is a percentage that the tip/base will move away from the xy and xytext coordinates.

import matplotlib.pyplot as plt

plt.annotate('Here it is!',xy=(-1,-1),xytext=(0,0),
             arrowprops=dict(lw=1.5, shrink=0.15))

plt.xlim(-10,10)
plt.ylim(-10,10)

plt.show()