reducer.median.forbid-nulls function outputs for each tick the median, as defined by the NIST, of the values of Geo Time Series™ which are in the same equivalence class.
It operates on LONG and DOUBLE and it always returns a DOUBLE.
If this reducer encouters a NULL value, ie ticks do not match between Geo Times Series™ in the same equivalence class, it throws an error.
As the median is effectively computed using one or two points, the location/elevation of the result is:
- not defined is there is no location/elevation
- the value of the location/elevation if only one point has this info
- the centroid/mean of the location/elevation if the two points have this info.