What does the ion() function do?

Good afternoon,
I wanted to ask about “ion()”. I’ve started learning Brian2 one month ago, but I’ve never seen “ion()” before on Tutorial (https://brian2.readthedocs.io/en/stable/advanced/interface.html). Could you tell please what is the functionality of “ion()” what does “ion()” do?

import brian2 as b2


I was working on this source https://github.com/zxzhijia/Brian2STDPMNIST which is the brian2 version of main Diehl&Cook’s program.
I had this “ion()” from there.
Thank you

Ah, this is indeed quite confusing because the code you link to uses ion as b2.ion(). The ion function is not actually a Brian function, but it comes directly from matplotlib (as explained here, Brian imports everything from matplotlib automatically, which can lead to this kind of confusion). It is used to switch to the “interactive mode”, which is explained in more detail in the matplotlib documentation. Whether you need it or not depends on how you run Brian code: it does not do anything in a jupyter notebook for example. In a script or in an interactive Python console it means that a call to plot will directly show the plot, instead of waiting for a show() command.

Note that there are various ways to find out what a function does in Python. For example, in a jupyter notebook you could type b2.ion? to get help, and in a standard Python console you could type help(b2.ion).

PS: I took the liberty to change the title of your question to avoid confusion with the brian2tools package. I also slightly reformatted your question, note that for Python code you can enclose it in

← here goes your code

to get it displayed nicely.

Thank you Mr. @mstimberg. for your detailed explanations.

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