The current implementation of plot_samples_distance produces interpolated matrix plots, while I'd rather prefer the data shown without interpolation. For this, interpolation="nearest" might be added to the imshow call (line 305 in base.py).
If this interpolated representation is intended, I would be gratefull for an option, that disables his feature.
indeed interpolation here is undesired... I would vote to hardcode 'nearest' interpolation for this plot. Feel welcome to send this huge PR ;)
Current master does this already.