def METHOD_NAME(self, widget):
    '''Test the helper method for providing conversion function'''
    widget.xLabel="x"
    assert widget.floatInvTransform(5.0) == 5.0
    widget.xLabel="x^(2)"
    assert widget.floatInvTransform(25.0) == 5.0
    widget.xLabel="x^(4)"
    assert widget.floatInvTransform(81.0) == 3.0
    widget.xLabel="log10(x)"
    assert widget.floatInvTransform(2.0) == 100.0
    widget.xLabel="ln(x)"
    assert widget.floatInvTransform(1.0) == numpy.exp(1)
    widget.xLabel="log10(x^(4))"
    assert widget.floatInvTransform(4.0) == 10.0