including plots in an IPython Notebook without %matplotlib magic function - python

Setup:
I have an IPython Notebook I’d like to include in the tutorials section of my docs. I’ve written a .ipynb —> .rst conversion script (using pandoc) that works as follows: the notebook is first converted to a .py file, which is executed as a script, and if the script execution raises no exceptions, an .rst export is triggered and a link to that tutorial is built in the appropriate spot of the docs. That way, the tutorials can be integrated into my docs only under the condition that the code does what the tutorial says it does. This method was developed as a result of the following question: Raise exception if script fails
Ok, so here is the problem. I’d like for some of the .ipynb tutorials to include in-line plots with matplotlib. The way I display plots in an IPython Notebook is using the magic function call:
%matplotlib inline
However, if this command appears in a python executable script, python raises an exception. So none of my tutorials can currently include plots.
Question:
So my question is this: how can I include in-line plots in a Notebook in a way that will not raise an exception when the notebook is exported to a .py file and executed as a script? Or, short of that, any suggestions for another workaround?

Use this instead:
from IPython import get_ipython
ipython = get_ipython()
if ipython:
ipython.magic("matplotlib inline")

Currently, there should be no real need to use %matplotlib inline magic in jupyter. Instead, this should display nicely:
import matplotlib.pyplot as plt
fig, ax = plt.subplot(111)
ax.plot([3,4,2,5])
fig

Related

How can I display an image on VS Code and PyCharm?

I want to choose the best IDE for Python programming so I'm testing different softwares but I have problem.
When I try this code blocks on VS Code I don't see any error but the image is not showing
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
image = mpimg.imread('exit-ramp.jpg')
plt.imshow(image)
VS Code
When I try run the same code on PyCharm I see some errors
PyCharm
But when I run the same code on Jupyter Notebook it works. What can I do?
Bro, try that:
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
image = mpimg.imread('exit-ramp.jpg')
plt.imshow(image)
plt.show()
i've made a test in my vscode.
Few weeks ago i used a lot pycharm... but i get some library errors with pandas and pycharm its a little bit heavy.
VSCODE its light and i didnt get any library error that i had with pycharm.
I believe this is a backend problem to be changed in matplotlib. If you start your Python shell whether you are in a bash shell or in vscode, you should use a backend that will show the plot. Otherwise the plt.show() call is required.
So, one solution is to change the backend either manually in you Python shell or when starting the Python shell as explained here below.
Note, however, that I always use the qt5 backend but got the same issue as yours: no plot appears. I changed to the Qt5Agg backend and it worked for me (providing PyQt5 is installed).
So, first solution, you can try to set the backend when starting the Python shell:
ipython --pylab Qt5Agg
You should use a GUI backend amongst the possible backend. If you do not known, try to replace Qt5Agg by auto
The second solution consists in changing the backend manually once in the Python shell:
import matplotlib as plt
plt.use('Qt5Agg')
Right click on your code -> Run current file in interactive window.

Pycharm Jupyter Interactive Matplotlib

Interactive matplotlib plotting is already a thing, but does not work properly in Pycharm, when used within a jupyter notebook.
The %matplotlib notebook does not work (throws no error, but I get <IPython ... JavaScript object> instead of a plot. If I plot normally (also with or without plt.show()) I just get a png and cannot interact in any way (even if, e.g., sliders are visible).
I couldn't find any answers elsewhere to this exact problem. It might be working in the browser version of jupyter, but I would like to stick to using PyCharm.
Pycharm v 2017.3 Community Edition
You can try:
import matplotlib
matplotlib.use('Qt5Agg')
import matplotlib.pyplot as plt
Instead of importing only the peplos.
It's a trick I found on forum of Jetbrains
https://intellij-support.jetbrains.com/hc/en-us/community/posts/115000736584-SciView-in-PyCharm-2017-3-reduces-functionality-of-Matplotlib It works for me. With this, you skip actually the Sciview and plot in a normal matplotlib window

%matplotlib inline doesn't work on iPython and Jupyter console

I'm trying out Jupyter console for the first time, but can't get the %matplotlib inline magic to work. Below is a screenshot of an example session:
The plot shows in a separate window after I run Line 6, and Line 7 doesn't do anything.
When I run %matplotlib --list, inline is given as one of the options:
Available matplotlib backends: ['osx', 'qt4', 'qt5', 'gtk3', 'notebook', 'wx', 'qt',
'nbagg', 'agg', 'gtk', 'tk', 'ipympl', 'inline']
When I try to use another backend, say qt5, it gives an error message because I don't have any Qt installed.
ImportError: Matplotlib qt-based backends require an external PyQt4, PyQt5, or PySide
package to be installed, but it was not found.
Running %matplotlib?? reads:
If you are using the inline matplotlib backend in the IPython Notebook
you can set which figure formats are enabled using the following::
In [1]: from IPython.display import set_matplotlib_formats
In [2]: set_matplotlib_formats('pdf', 'svg')
The default for inline figures sets `bbox_inches` to 'tight'. This can
cause discrepancies between the displayed image and the identical
image created using `savefig`. This behavior can be disabled using the
`%config` magic::
In [3]: %config InlineBackend.print_figure_kwargs = {'bbox_inches':None}
But I don't know if it's something I can tweak around to solve my issue.
When I try it the magic IPython console, it says inline is an Unknown Backend.
UnknownBackend: No event loop integration for u'inline'. Supported event loops are: qt,
qt4, qt5, gtk, gtk2, gtk3, tk, wx, pyglet, glut, osx
I've also found this issue on github after some googling but I don't even know if it's relevant to my situation (most of their conversation didn't make sense to me lol).
Lastly, I'm not sure if this issue is related at all, but here it is, just in case: when I try to open Vim in Jupyter via the !vim command, it glitches pretty badly, preventing me from even exiting out of Jupyter itself without closing the terminal altogther. Vim works perfectly fine when called inside IPython console, however.
I'm using matplotlib 2.0.0.
If anyone could help me figure this out, that'd be great! Thank you!
You’re running a console which is completely text based and incapable of showing images. Therefore, although inline is available, it's not producing inline output.
I'm not sure why it doesn't throw an error, though, which it does in my case:
You can use %matplotlib inline in a GUI console, like Jupyter QTConsole
or in a jupyter notebook in the browser
%matplotlib without the inline works for me (I'm using osx and IPython 7.0.1)
If you're running an old version of ipython try %pylab inline instead. See notes in this tutorial

matplotlib inline syntax error

I'm testing a python program, which contains calling for IPython. But I got errors in the following code:
If I use
%matplotlib inline
I got a syntax error at the "%" symbol.
I found a solution to this problem using:
from IPython import get_ipython
get_ipython().run_line_magic('matplotlib', 'inline')
I got error saying:
AttributeError: 'NoneType' object has no attribute 'run_line_magic'
I'm using Ubuntu 16.04 and running the code via command line. How can I fix this ?
This %matplotlib magic is used to display graphs (of matplotlib.pyplot objects). This needs UI to display. So cannot be display on command prompt.
According to IPython documentation,
If the %matplotlib magic is called without an argument, the output of a plotting command is displayed using the default matplotlib backend in a separate window. Alternatively, the backend can be explicitly requested using, for example:
%matplotlib gtk
A particularly interesting backend, provided by IPython, is the inline backend. This is available only for the Jupyter Notebook and the Jupyter QtConsole. It can be invoked as follows:
%matplotlib inline
Simple solution would be to replace %matplotlib inline with %matplotlib and run it using ipython.
Alternatively, what you could do is download jupyter notebook and run that code there.
Or as #tihom said in comments, you could comment or remove that line and run the code but this wouldn't display the graphs and other things.
You can use pylab mode in ipython. Simply run ipython --pylab in the terminal. That will launch ipython configured to be able to support the matplotlib GUI backend

Python Saving PNG in Terminal vs IPython Notebook

I am writing a basic Python module which contains a function that plots some data from a Pandas DataFrame. The problem is that I expect users to call this function from both the interactive shell and IPython notebooks. Unfortunately, our interactive shell environment does not have any valid DISPLAY options for matplotlib to use, so I want my function (or the full module) to behave slightly different depending on which environment it is loaded into. (E.g., the default is show the plot without saving in IPython, and save the plot without showing in the shell).
This question gives me a partial answer, in that I can explicitly tell users to write matplotlib.use('Agg') before they ever import my module, but surely there is a more automated backend way to handle this?
You could try checking if you are running into the situation (empty $DISPLAY) and default users to the Agg backend, rather than asking them to do so.
def configure_matplotlib():
import os
if 'DISPLAY' not in os.environ:
if matplotlib.get_backend() != 'Agg':
matplotlib.use('Agg')
import matplotlib
configure_matplotlib()
import matplotlib.pyplot as plt
...
Now matplotlib.use has no effect once pyplot has been imported, but if your users have already done so, they probably have a working configuration anyway.

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