Get legend as a separate picture in Matplotlib

Question

I\'m developing a Web application and want to display a figure and its legend in different locations on the page. Which means I need to save the legend as a separate png fil

Answer 1

In November 2020, I tried almost everything on this post, but none worked for me. After struggling for a while, I found a solution that does what I want.

Pretend you want to draw a figure and a legend separately that looks like below (apparently I don't have enough reputation to embed pictures in a post; click the links to see the picture).

import matplotlib.pyplot as plt
%matplotlib inline

fig, ax = plt.subplots()

ax.plot([1, 2, 3], label="test1")
ax.plot([3, 2, 1], label="test2")

ax.legend()

target figure

You can separate the figure and the legend in two different ax objects:

fig, [ax1, ax2] = plt.subplots(1, 2)

ax1.plot([1, 2, 3], label="test1")
ax1.plot([3, 2, 1], label="test2")

ax2.plot([1, 2, 3], label="test1")
ax2.plot([3, 2, 1], label="test2")
h, l = ax2.get_legend_handles_labels()
ax2.clear()
ax2.legend(h, l, loc='upper left')
ax2.axis('off')

fixed figure 1

You can easily control where the legend should go:

fig, [ax1, ax2] = plt.subplots(2, 1)

ax1.plot([1, 2, 3], label="test1")
ax1.plot([3, 2, 1], label="test2")

ax2.plot([1, 2, 3], label="test1")
ax2.plot([3, 2, 1], label="test2")
h, l = ax2.get_legend_handles_labels()
ax2.clear()
ax2.legend(h, l, loc='upper left')
ax2.axis('off')

fixed figure 2