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Create Multipage PDF in matplotlib without drawing figure on desktop

In the following example code...
from matplotlib.backends.backend_pdf import PdfPages
import matplotlib.pyplot as plt
with PdfPages('multipage_pdf.pdf') as pdf:
for i in range(10):
fig = plt.figure()
ax = fig.add_subplot(111)
ax.scatter([0, 1, 2], [0, 1, 2])
pdf.savefig()
plt.close()
... every single plot pops up a windows with the actual canvas. Is there an elegant solution to skip the actual drawing of the canvas on the screen and draw the plot directly into a multipage pdf?
PS: Problem only caused when running code within spyder, so related to spyder and not to anything else. Running code directly using python does not cause this popping up of windows.

I think what you are looking for is to clear the figure.
first_page = plt.figure(figsize=(11.69, 8.27))
first_page.clf()
Check out the documentation:
https://matplotlib.org/3.1.1/api/_as_gen/matplotlib.pyplot.clf.html
Some examples:
https://www.programcreek.com/python/example/102298/matplotlib.pyplot.clf

The problem did not arise from matplotlib or anything similar, but just running the code from within Spyder caused this problem. Running the code using python directly does not cause the issues I had before.

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.

How to show matplotlib plot from a figure object

My code contains the following lines:
from matplotlib.figure import Figure
figure = Figure(figsize=(10, 5), dpi=dpi)
How can I get matplotlib to show this figure? I also show it embedded in tkinter, which workes fine. However I would also be able to show it in the standard matplotlib window. But I can't for the life of me get it to work.

According to AttributeError while trying to load the pickled matplotlib figure, a simple workaround is:
fig = plt.Figure(...)
......
managed_fig = plt.figure(...)
canvas_manager = managed_fig.canvas.manager
canvas_manager.canvas.figure = fig
fig.set_canvas(canvas_manager.canvas)
Note that I encountered "'Figure' object has no attribute '_original_dpi'" in my environment. Not sure if it's some compatibility issue between my PyPlot and the PyQt5. Just did a hack:
fig._original_dpi = 60
to get around this. Not sure if there are any better solutions.

I usually use matplotlib's pyplot for immediate generation (or produce images in jupyter notebooks). This would look like the following:
import matplotlib.pyplot as plt
figure = plt.figure(figsize=(10, 5), dpi=dpi)
plt.show()
This shows the (blank) figure as desired.

pyplot.show function in spyder with python 3.4

I'm a novice with Python and working through "Machine Learning In Action" by P. Harrington. I'm having issues seeing my plot when using the pyplot.show() function. Below is the code that I'm entering in the IPython console on the bottom right of Spyder.
import matplotlib
import matplotlib.pyplot as plt
fig = plt.figure()
ax = fig.add_subplot(111)
ax.scatter(datingDataMat[:,1], datingDataMat[:,2])
plt.show()
After I enter this last line, nothing happens. Does anyone have an idea why it doesn't appear?

Matplotlib figures not changing interactively - Canopy Ipython

I am trying to use the ipython in canopy with matplotlib to prepare graphs (backend set to qt). I wrote the following code line by line int the terminal
import matplotlib.pyplot as plt
fig = plt.figure()
s = fig.add_subplot(1,1,1)
after the second line I can see the figure being made. However after the third line I do not see the sub plot being created. However If I print fig, the sub-plot is can be seen both inline and in the figure window created. This sub-plot also magically appears if I try to zoom. Similar thing happens every time i plot something on the figure. The old version is displayed till I either print the figure or if i try to modify the view using the GUI tools. This is really annoying. It would be great if someone could tell me where the problem is.
Edit: Tried using fig.show() which does not work. Also when I use the plt.plot() directly, there seems to be no problem. The problem comes only when i use fig or any of its subplots

type:
fig.show() when you need to update it.

you should try using fig.canvas.draw() instead of using fig.show() when it comes to interactive plots.
import matplotlib.pyplot as plt
fig = plt.figure()
fig.show()
## should show an empty figure ##
s = fig.add_subplot(1,1,1)
fig.show()
## things stay unchanged ##
fig.canvas.draw()
## things should be OK now ##