inst/shadow9/mean - Rework function to streamline input processing and reduce called function overhead. Implement reshaping to dim1 for streamlined operations. Add BISTs to ensure compatible class handling.
inst/shadow9/median - Additional called function streamlining. Simplify code paths when no NaN values are present. Change handling of ints to avoid summation overflow and/or limits of double precision processing for large (u)int64 values.
inst/fillmissing - Streamline columnwise_median subfunction following improvements to median.
Note: still looking at possibility of fixing bug #54567 (int64 overflow and precision loss) in mean before opening patch to push group to core.
Note: still looking at possibility of fixing bug #54567 (int64 overflow and precision loss) in mean before opening patch to push group to core.