Add hint about `plt.show()` or similar to get plots to show in terminal

[JacekHoleczek]

It seems I am missing something very basic.

The "Basic file I/O with Uproot" chapter contains: h.to_hist().plot()

The "TTree details" chapter contains (twice): masshist.plot()

It seems you expect that these histograms are "displayed", but I get completely nothing physically drawn on my screen (a local X11 server and a "ssh -X -Y" connection to a remote Linux machine with an "activated" Python 3.11.4 conda-forge environment).

Well, I can get them "displayed", if I afterward execute (but that is not shown in the tutorial):

import matplotlib.pyplot as plt; plt.show()

In the "Histogram manipulations and fitting" chapter, in the "Matplotlib" section, there is (and that is the only place in the tutorial which imports matplotlib):

import matplotlib.pyplot as plt
plt.hist(tree["M"].array())

But this does not physically draw it either (the final "plt.show()" is missing).

[klieret]

Hi @JacekHoleczek. Thank you for this report. The tutorial might assume that we're in a notebook, probably with %matplotlib inline on top.

If you want to use the command line, you might want to use the ipython REPL rather than the plain python REPL.

See this answer.

[JacekHoleczek]

In this case, could you please, add a dedicated paragraph (at least somewhere before the first "plot()" command) that says something like this:

In order to enable interactive mode, which shows / updates figures after every plotting command so that calling show() is not necessary, one needs to execute once in a session:
import matplotlib.pyplot as plt; plt.ion()

[stale]

This issue or pull request has been automatically marked as stale because it has not had recent activity. Please manually close it, if it is no longer relevant, or ask for help or support to help getting it unstuck. Let me bring this to the attention of @klieret @wdconinc @michmx for now.