QT5Agg backend yields figure error during plotting

[sosey]

    237         # The need for this change is documented here
    238         # http://pyqt.sourceforge.net/Docs/PyQt5/pyqt4_differences.html#cooperative-multi-inheritance
--> 239         super(FigureCanvasQT, self).__init__(figure=figure)
    240         self.figure = figure
    241         self.setMouseTracking(True)

[sosey]

may not be related, but switching to the TkAgg backend on my mac fixed the double-click display plot issue, in Qt5 i've needed to hit the exam key twice to get the plot to display during the imexam loop.