Python3.5 backend_tkagg no longer available?
<p>I'm trying to run an application that was running before.  It used to run on both Ubuntu and Windows 7.  I now have a Windows 10 machine, and the code fails. It might be because I'm on python 3.5 now, though I frankly can't remember what I was on on the other machines (which are no longer available).</p>

<p>The key lines are:</p>

<pre><code>import matplotlib
matplotlib.use("TkAgg")
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
</code></pre>

<p>which has been lifted from various places some time ago.  However, now when I run it, it throws an error:</p>

<pre><code>Traceback (most recent call last):
  File "C:\....py", line 17, in &lt;module&gt;
    from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
  File "C:\Users\...\AppData\Local\Programs\Python\Python35-32\lib\site-packages\matplotlib\backends\backend_tkagg.py", line 13, in &lt;module&gt;
    import matplotlib.backends.tkagg as tkagg
  File "C:\Users\g...\AppData\Local\Programs\Python\Python35-32\lib\site-packages\matplotlib\backends\tkagg.py", line 9, in &lt;module&gt;
    from matplotlib.backends import _tkagg
ImportError: DLL load failed: The specified module could not be found.
</code></pre>

<p>In an interactive session, it seems that it's the third line that's failing:</p>

<pre><code>&gt;&gt;&gt; import matplotlib
&gt;&gt;&gt; matplotlib.use("TkAgg")
&gt;&gt;&gt; from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
Traceback (most recent call last):
  File "&lt;pyshell#4&gt;", line 1, in &lt;module&gt;
    from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
  File "C:\Users\...\AppData\Local\Programs\Python\Python35-32\lib\site-packages\matplotlib\backends\backend_tkagg.py", line 13, in &lt;module&gt;
    import matplotlib.backends.tkagg as tkagg
  File "C:\Users\...\AppData\Local\Programs\Python\Python35-32\lib\site-packages\matplotlib\backends\tkagg.py", line 9, in &lt;module&gt;
    from matplotlib.backends import _tkagg
ImportError: DLL load failed: The specified module could not be found.
</code></pre>

<p>I tried </p>

<pre><code>pip uninstall matplotlib
pip install matplotlib
</code></pre>

<p>in the command prompt, but the error remained.</p>

<p>It seems there may be a python-matplotlib-tk package, but I'm not sure what this is.</p>

<p>Should I drop back to python 3.4, or is there a solution for this?  Is this a known problem? </p>

<hr>

<p>In response to the below comment on installing matplotlib:</p>

<pre><code>C:\&gt;pip install matplotlib
Collecting matplotlib
  Downloading matplotlib-1.5.1-cp35-none-win32.whl (6.2MB)
    100% |################################| 6.2MB 67kB/s
Requirement already satisfied (use --upgrade to upgrade): numpy&gt;=1.6 in c:\users\...\appdata\local\programs\python\python35-32\lib\site-packages (from matplotlib)
Requirement already satisfied (use --upgrade to upgrade): pytz in c:\users\...\appdata\local\programs\python\python35-32\lib\site-packages (from matplotlib)
Requirement already satisfied (use --upgrade to upgrade): python-dateutil in c:\users\...\appdata\local\programs\python\python35-32\lib\site-packages (from matplotlib)
Requirement already satisfied (use --upgrade to upgrade): cycler in c:\users\...\appdata\local\programs\python\python35-32\lib\site-packages (from matplotlib)
Requirement already satisfied (use --upgrade to upgrade): pyparsing!=2.0.4,&gt;=1.5.6 in c:\users\...\appdata\local\programs\python\python35-32\lib\site-packages (from matplotlib)
Requirement already satisfied (use --upgrade to upgrade): six&gt;=1.5 in c:\users\...\appdata\local\programs\python\python35-32\lib\site-packages (from python-dateutil-&gt;matplotlib)
Installing collected packages: matplotlib
Successfully installed matplotlib-1.5.1
</code></pre>