Reduces a sorted series to at most two points per bucket (the bucket's minimum and
maximum, in time order), keeping every gap.
Runs of present values are reduced separately; a NaN point is kept between runs,
so a gap survives downsampling. Series that already fit are returned unchanged.
Reduces a sorted series to at most two points per bucket (the bucket's minimum and maximum, in time order), keeping every gap.
Runs of present values are reduced separately; a
NaNpoint is kept between runs, so a gap survives downsampling. Series that already fit are returned unchanged.