Aggregate forecast errors by a calendar key, one column per entry.
Groups every error series by an attribute of its DatetimeIndex (hour of day, by default) and aggregates each group — the systematic hour-of-day error profile of a day-ahead forecaster, for example. Render the result with spotforecast2.plots.evaluation.plot_error_profile.
Calendar key to group by. Options: - "hour": hour of day (0-23). - "dayofweek": day of week (0 = Monday). - "month": month of year (1-12). - "dayofyear": day of year (1-366). Defaults to "hour".