Proof of concept for plotting a taurus attribute with pyqtgraph

pgtaurus.py

import sys
import numpy
from taurus.external.qt import QtGui
from taurus.qt.qtgui.application import TaurusApplication
from taurus.qt.qtgui.base import TaurusBaseComponent
from pyqtgraph import PlotDataItem


class TaurusPlotDataItem(PlotDataItem, TaurusBaseComponent):
    """A taurus-ified PlotDataItem"""

    def __init__(self, *args, **kwargs):
        PlotDataItem.__init__(self, *args, **kwargs)
        TaurusBaseComponent.__init__(self, 'TaurusBaseComponent')

    def handleEvent(self, evt_src, evt_type, evt_value):
        try:
            y = evt_value.rvalue
            self.setData(y)
        except Exception, e:
            self.warning('Exception in handleEvent: %s', e)


if __name__ == '__main__':
    import pyqtgraph as pg

    app = TaurusApplication()
    
    # a standard pyqtgraph widget
    w = pg.PlotWidget()

    # adding a regular data item (non-taurus)
    c1 = pg.PlotDataItem(pen='b', fillLevel=0, brush='c')
    c1.setData(numpy.arange(300)/300.)
    w.addItem(c1)

    # adding a taurus data item
    c2 = TaurusPlotDataItem(pen='r', symbol='o')
    c2.setModel('eval:Quantity(rand(256),"m")')
    w.addItem(c2)

    w.show()

    sys.exit(app.exec_())

Note that pyqtgraph accepts pint.Quantities out-of-the-box!!