I am creating histogram with
pylab.hist(data,weights,histtype='step',normed=False,bins=150,cumulative=True)
getting (there are other plots, which are irrelevant now) the violet line
Why is the histogram dropping to zero at the end again? Cumulative functions should be in general non-decreasing. Is there a way to work around this, be it bug or feature?
This is default behaviour. Think of it as an outline of the histogram as a bar chart. As for a quick workaround, not that I am aware of. A solution would be to calculate the histogram on your own: python histogram one-liner