From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Stanton <stanton@haas.berkeley.edu>
Subject: Plotting in Python block won't over-write existing file
Date: Fri, 6 Mar 2015 10:41:48 -0800
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To: emacs-orgmode@gnu.org

Here=E2=80=99s a sample Python code block:

#+begin_src python :results file :exports both
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
import pandas as pd

df =3D pd.DataFrame({'date': [1900, 1901, 1902], 'x1' : [3, 4, 5], 'x2' =
: [6, 7, 9]})
df.set_index('date', inplace=3DTrue, drop=3DTrue)
df.plot()
plt.savefig('x4.png')
return 'x4.png' # return filename to org-mode
#+End_src

When I run it, the graph appears on the screen and in the named file, as =
desired.

However, if I go back, change one of the numbers, and rerun the block, =
while it claims to have run OK, the graph is not updated. I only get a =
new plot if I also change the file name (e.g., to x5.png). It looks like =
it=E2=80=99s refusing to over-write an existing file. Is there a reason =
for this, and is there a way to change this behavior?

By the way, this is with org-mode 8.3beta-884-g9ed426

Thanks.

Richard Stanton=