Resolve duplicate timestamps across all data columns. Groups rows that share the same time_col value and collapses them using the chosen aggregation. All columns except time_col are aggregated. The resulting frame is sorted chronologically, re-indexed, and returned.
Aggregation applied when collapsing duplicate rows. Accepts any string recognised by pandas.core.groupby.GroupBy.agg() ("mean", "median", "min", "max", "sum", "std", "var", "first", "last") as well as "mode" (most frequent value per group) or any custom callable. Defaults to "mean".