An S4 class to represent model/scenario planning horizon with intervals (year-steps)

Slots

name: character. Name of the horizon object. Used to distinguish between different horizons in the model or scenario, including the automatic creation of the folder name for the model/scenario scripts.
desc: character. Description of the horizon object, for own references.
period: integer. A planning period defined as a sequence of years (arranged, without gaps) of the model planning (e.g. optimization) window. Data with years before or after the planning period can present in the model-objects and will be taken into account during interpolation of the model parameters.
intervals: data.frame. Data frame with the start, middle, and end year of every modelled interval, plus an optional display label. start, mid and end are integer years; mid is the milestone and the model's key for the period. label is a character display name, unique across intervals, filled from mid when not given, and rendered fiscally (FY2025-26) when the calendar carries a non-January year_start. The label is presentation only and never reaches the solver – see year_label().