deletions | additions       diff --git a/Concepts.tex b/Concepts.tex  index 76ad9eb..16590cb 100644  --- a/Concepts.tex  +++ b/Concepts.tex 
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Additional plots can be manually created directly with matplotlib.  Usually plots are displayed inline in the notebook. However a few plot functions such as \verb|timetrace| and \verb|hist2d_alex| have interactive features that can be enabled when using the QT4 backend that open the plot in an external window. It is possible to switching switch  backend from inline to QT and vice versa using the ipython commands \verb|%matplotlib qt| and \verb|%matplotlib inline|. For example, after switching to the QT4 backend the following commads:  \begin{verbatim}