Fix histograms with very many entries not being plotted
Release notes
Fix histograms with very many entries not being plotted
Details
I ran into a problem where a histogram with a lot of entries (ca 4e9, I was doing the probably unreasonable thing of running over unskimmed samples and making a histogram before any cuts) was not being plotted. It turned out that there where so many entries that an overflow occurred, so it became negative and nEntries<1
became true. Changing it to nEntries==0
fixes this.