Histograms that include empty bins

[Dima K. <gn...@di...>]

Hi. I just tried to patch gnuplot to do something that I thought would
be simple, but it actually looks like it wouldn't be. Can I get a
suggestion?

I'm making a simple histogram. This works as expected:

set boxwidth 1
histbin(x) = floor(0.5 + x)
plot '-' using (histbin($1)):(1.0) smooth freq with boxes fill solid border lt -1 
1
2
4
5
e

Here I get 4 bins of width 1, centered at 1, 2, 4, 5. Notably, there's a
gap: there's no bin centered at 3. Internally, gnuplot omits this bin
entirely, instead of producing an empty bin. This matters if you make a
this plot "with linespoints" instead of "with boxes". I want a plot that
includes the point (3,0), but the current code doesn't include that
point. Is there an obvious way to include that?

Thanks!