Commenting out the set_xscale and set_yscale lines results in a working (visible) plot, but with those lines I get an empty plot window.. Since the x and y coordinates are all nonnegative, I would ...

If I use a larger font size than the default one, a large range of data in Log scale plot results in incorrect display of minor ticks. I would expect the minor ticks to be not displayed at all, or ...