Version: qwt 6.0.1
I've tried to develop logarithmic scaling for Histogram (As it works fine for curve, actually).
But the error is that the data are not drawn, so the plot is empty.
I've used simple line to enable scaling plot->setAxisScaleEngine(QwtPlot::yLeft, new QwtLog10ScaleEngine); (look throw the code in attachment).
In result I have