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How to remove a residual plot in Jupyter output after displaying a matplotlib animation?

I want to display an animation in Jupyter using Matplotlib. Here is some basic example:
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
fig, ax = plt.subplots()
line, = ax.plot(np.random.rand(10))
ax.set_ylim(0, 1)
def update(data):
line.set_ydata(data)
return line,
def data_gen():
while True:
yield np.random.rand(10)
ani = animation.FuncAnimation(fig, update, data_gen, interval=100);
from IPython.display import HTML
HTML(ani.to_jshtml())
When I run the code for the first time (or after restarting the kernel) I get what I want:
However, when I run the very same code for the second time I get a leftover in the left bottom:
I noticed that when I add %matplotlib inline at the top, then I got the bad output even after restarting the kernel. Thus my guess is that I have to set the magic command %matplotlib to default at the top each time I create an animation, but I can't even find if %matplotlib have a default value.
I use Anaconda. Here are my versions:
Conda version: 4.4.10
Python version: Python 3.6.4 :: Anaconda, Inc.
IPython version: 6.2.1
Jupyter version: 5.4.0

I used plt.close() to stop the first (unwanted) plot, and have not seen issues running the animation in a separate cell. I believe the issue is similar to those linked in the comments, jupyter is automatically displaying an unwanted plot for the first two lines - fig, ax = plt.subplots()
line, = ax.plot(np.random.rand(10)). I tired suggestions such as using semicolons at end of lines and a few different magic attempts, but no joy. A more concrete solution will no doubt appear, but for now....

I've got some problems of iteration with my animation function (matplotlib.animation/Python)

I'm trying to create an animated histogram for work, using matplotlib.animation, but animation.FuncAnimation is not functioning properly : when using this code, that i found on the official documentation,
"""
A simple example of an animated plot
"""
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
fig, ax = plt.subplots()
x = np.arange(0, 2*np.pi, 0.01)
line, = ax.plot(x, np.sin(x))
def animate(i):
print(i)
line.set_ydata(np.sin(x + i/10.0)) # update the data
return line,
# Init only required for blitting to give a clean slate.
def init():
line.set_ydata(np.ma.array(x, mask=True))
return line,
ani = animation.FuncAnimation(fig, animate, np.arange(1, 200),init_func=init,interval=25, blit=True)
plt.show()
I get as final result the graph created by init() function (an empty graph also), but no animate iterations. Furthermore, I tested other codes, which practically gave me the same result : i get the initialization, or the first frame, but not more. matplotlib and matplotlib.animation are installed, everything seems to be ok, except it doesn't work. Have someone an idea how to fix it ? (Thank you in advance :) !)

I had the same issue working with Jupyter notebook and I solved it by inserting the line
%matplotlib notebook
in the code.

It may be that IPython inside your Spyder is configured to automatically use the inline backend. This would show your plots inside the console as png images. Of course png images cannot be animated.
I would suggest not to use IPython but execute the script in a dedicated Python console. In Spyder, go to Run/Configure.. and set the option to new dedicated Python console.

spyder won't show the matplotlib window

i am using spyder to run the following script
import matplotlib.pyplot as plt
fig = plt.figure()
ax=fig.add_subplot(111)
ax.plot([2,1,3])
plt.ion()
plt.show()
input('something')
the problem is, that the matplotlib-window appears at the end of the script (after i entered 'something')
when i'm executing this script in a terminal the window appears and i can enter 'something' simultaneously - this is what i need.
does someone has an idea what causes this problem?

Jupyter (IPython) notebook: plot in the qt mode + prompt raw_input()

I am trying to plot in Jupyter notebook (Python 2.7), then prompt user for input, save it and then change the plot (this is a crucial point: I don't want to create a new plot, I need to modify the old one after user input). This completely fails to work. Instead of showing the figure and then prompting for input, it opens the figure window, but freezes (doesn't display anything) until I respond to the raw_input() prompt. Only then it plots.
Simple version of the code to show the error:
import matplotlib.pyplot as plt
%matplotlib qt
fig = plt.figure()
ax = fig.add_subplot(111)
ax.plot([1,2,3],[1,2,3])
plt.show(block=False)
my_input = raw_input()
This bug only appears when I use %matplotlib qt, but I have to use it, because with %matplotlib inline I am unable to modify the plot after it was displayed (at least as far as I am aware).
In fact, I noticed that it freezes until the end of the cell execution, even if it is just time.sleep().
Am I missing something? Some settings of how matplotlib displays figures?

Since I am using Python3 I had to change raw_input() to input() and removed the block=False because IPython told me that this is an unknown attribute.
This should work nice:
import matplotlib.pyplot as plt
%matplotlib inline
fig = plt.figure()
ax = fig.add_subplot(111)
ax.plot([1,2,3], [1,2,3])
plt.show()
my_input = input()
Fur sure, you need to adapt this back to Python2 to fit your needs.

Close pyplot figure using the keyboard on Mac OS X

Is there a way to close a pyplot figure in OS X using the keyboard (as far as I can see you can only close it by clicking the window close button)?
I tried many key combinations like command-Q, command-W, and similar, but none of them appear to work on my system.
I also tried this code posted here:
#!/usr/bin/env python
import matplotlib.pyplot as plt
plt.plot(range(10))
def quit_figure(event):
if event.key == 'q':
plt.close(event.canvas.figure)
cid = plt.gcf().canvas.mpl_connect('key_press_event', quit_figure)
plt.show()
However, the above doesn't work on OS X either. I tried adding print statements to quit_figure, but it seems like it's never called.
I'm trying this on the latest public OS X, matplotlib version 1.1.1, and the standard Python that comes with OS X (2.7.3). Any ideas on how to fix this? It's very annoying to have to reach for the mouse every time.

This is definitely a bug in the default OS X backend used by pyplot. Adding the following two lines at the top of the file switches to a different backend that works for me, if this helps anyone else.
import matplotlib
matplotlib.use('TKAgg')

I got around this by replacing
plt.show()
with
plt.show(block=False)
input("Hit Enter To Close")
plt.close()
A hack at its best, but I hope that helps someone

use interactive mode:
import matplotlib.pyplot as plt
# Enable interactive mode:
plt.ion()
# Make your plot: No need to call plt.show() in interactive mode
plt.plot(range(10))
# Close the active plot:
plt.close()
# Plots can also be closed via plt.close('all') to close all open plots or
# plt.close(figure_name) for named figures.
Checkout the "What is interactive mode?" section in this documentation
Interactive mode can be turned off at any point with plt.ioff()

When you have focus in the matplotlib window, the official keyboard shortcut is ctrl-W by this:
http://matplotlib.org/1.2.1/users/navigation_toolbar.html
As this is a very un-Mac way to do things, it is actually cmd-W. Not so easy to guess, is it?
If you are using an interactive shell, you can also close the window programmatically. See:
When to use cla(), clf() or close() for clearing a plot in matplotlib?
So, if you use pylab or equivalent (everything in the same namespace), it is just close(fig). If you are loading the libraries manually, you need to take close from the right namespace, for example:
import matplotlib.pyplot as plt
fig = plt.figure()
plt.plot([0,1,2],[0,1,0],'r')
fig.show()
plt.close(fig)
The only catch here is that there is no such thing as fig.close even though one would expect. On the other hand, you can use plt.close('all') to regain your desktop.