Where binning stops along y: bins are added from start by size until one reaches or passes end. Default: the data maximum.
size?
unknown
Bin width along y. Default: a round size giving about as many bins as samples per bin (with nbinsy: at most that many bins). On date axes, ms or 'M<n>' for months ('M1', 'M3' quarters, 'M12' years); on category axes, the number of categories per bin (default 1).
start?
unknown
First bin edge along y. Default: the data minimum moved down to a round value, off the data (integer data in bins of 5 starts at -0.5, so 0–4 fall in the first bin). A date string on date axes, a category index (e.g. -0.5) on category axes. In a bin group, the first explicit start wins and the other traces' starts are moved down onto its bin grid.
