def __init__(self, parent):
QwtPlot.__init__(self, parent)
self.variables = []
self.insertLegend(QwtLegend(self), QwtPlot.TopLegend)
self.setCanvasBackground(Qt.white)
self.magnifier = QwtPlotMagnifier(self.canvas())
self.magnifier.setAxisEnabled(QwtPlot.xBottom, False)
self.magnifier.setAxisEnabled(QwtPlot.yLeft, True)
self.panner = QwtPlotPanner(self.canvas())
self.panner.setAxisEnabled(QwtPlot.xBottom, False)
self.panner.setAxisEnabled(QwtPlot.yLeft, True)
