Description
Bug report
Bug summary
Running plt.subplot after the respective subplot has already been created shows a warning. This behaviour is expected for fig.add_subplot. However in pyplot this is to my knowledge the recommended way to activate a subplot, as seen from the tutorial.
Code for reproduction
The following is the code from the second code box in the Working with multiple figures and axes section of the basic pyplot guide.
import matplotlib.pyplot as plt
plt.figure(1) # the first figure
plt.subplot(211) # the first subplot in the first figure
plt.plot([1, 2, 3])
plt.subplot(212) # the second subplot in the first figure
plt.plot([4, 5, 6])
plt.figure(2) # a second figure
plt.plot([4, 5, 6]) # creates a subplot(111) by default
plt.figure(1) # figure 1 current; subplot(212) still current
plt.subplot(211) # make subplot(211) in figure1 current
plt.title('Easy as 1, 2, 3') # subplot 211 title
Actual outcome
When being run it produces a warning.
MatplotlibDeprecationWarning: Adding an axes using the same arguments as a previous axes currently reuses the earlier instance. In a future version, a new instance will always be created and returned. Meanwhile, this warning can be suppressed, and the future behavior ensured, by passing a unique label to each axes instance.
Expected outcome
No warning. Using pyplot.subplot(211) should just activate the subplot, as described in the tutorial.
Alternatively, there needs to be another way to activate a subplot in pyplot (without having stored any handle to it previously).
Matplotlib version
- Matplotlib version: 2.2.2, 3.0.0 (possibly others)