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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Hi Ben<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">>When you say first and second flush_events(), do you mean the
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">>first and second iterations, or fig_A and fig_B?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">The latter:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"> fig_A.canvas.flush_events() <span style="font-family:Wingdings">
ß</span> 350ms<br>
fig_B.canvas.flush_events() <span style="font-family:Wingdings">ß</span> 1ms<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">These timings repeat on each iteration.<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Best regards<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">David<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Benjamin Root [mailto:ben.v.root@gmail.com]
<br>
<b>Sent:</b> 25 July 2017 15:46<br>
<b>To:</b> David Aldrich <David.Aldrich@EMEA.NEC.COM><br>
<b>Cc:</b> matplotlib-users@python.org<br>
<b>Subject:</b> Re: [Matplotlib-users] Why is flush_events() taking longer than expected?<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">When you say first and second flush_events(), do you mean the first and second iterations, or fig_A and fig_B?<o:p></o:p></p>
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<p class="MsoNormal">Ben Root<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Fri, Jul 21, 2017 at 9:33 AM, David Aldrich <<a href="mailto:David.Aldrich@emea.nec.com" target="_blank">David.Aldrich@emea.nec.com</a>> wrote:<o:p></o:p></p>
<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm">
<p class="MsoNormal">Hi<br>
<br>
I am using Matplotlib 2.0.2 in a Python 3.6 script on Windows 10 to plot data received over a network connection. New data arrives 4 times per second. I need to update two figures fig_A and fig_B, each containing 8 subplots. The hardware is a fast i7 laptop.<br>
<br>
My main execution loop is:<br>
<br>
plt.draw()<br>
<br>
while (True):<br>
fig_A.canvas.flush_events()<br>
fig_B.canvas.flush_events()<br>
updatePlots() # Polls socket for data and updates scatter collections<br>
fig_A.canvas.draw_idle()<br>
fig_B.canvas.draw_idle()<br>
<br>
plt.waitforbuttonpress()<br>
<br>
I have timed the code and found that the first flush_events() call in the loop takes 350ms. The second flush_events() call takes <1ms.<br>
350ms seems very long and is restricting the update rate.<br>
<br>
Why might flush_events() be taking so long?<br>
<br>
(I have not changed the backend from the default, which I believe is TkAgg).<br>
<br>
Best regards<br>
<br>
David<br>
<br>
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