muse2/
time_slice.rs

1//! Code for working with time slices.
2//!
3//! Time slices provide a mechanism for users to indicate production etc. varies with the time of
4//! day and time of year.
5use crate::id::{IDCollection, define_id_type};
6use crate::units::{Dimensionless, Year};
7use anyhow::{Context, Result};
8use indexmap::{IndexMap, IndexSet};
9use itertools::Itertools;
10use serde::de::Error;
11use serde::{Deserialize, Serialize};
12use serde_string_enum::DeserializeLabeledStringEnum;
13use std::fmt::Display;
14use std::iter;
15
16define_id_type! {Season}
17define_id_type! {TimeOfDay}
18
19/// An ID describing season and time of day
20#[derive(Hash, Eq, PartialEq, Ord, PartialOrd, Clone, Debug)]
21pub struct TimeSliceID {
22    /// The name of each season.
23    pub season: Season,
24    /// The name of each time slice within a day.
25    pub time_of_day: TimeOfDay,
26}
27
28/// Only implement for tests as this is a bit of a footgun
29#[cfg(test)]
30impl From<&str> for TimeSliceID {
31    fn from(value: &str) -> Self {
32        let (season, time_of_day) = value
33            .split(".")
34            .collect_tuple()
35            .expect("Time slice not in form season.time_of_day");
36        TimeSliceID {
37            season: season.into(),
38            time_of_day: time_of_day.into(),
39        }
40    }
41}
42
43impl Display for TimeSliceID {
44    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
45        write!(f, "{}.{}", self.season, self.time_of_day)
46    }
47}
48
49impl<'de> Deserialize<'de> for TimeSliceID {
50    fn deserialize<D>(deserialiser: D) -> std::result::Result<Self, D::Error>
51    where
52        D: serde::Deserializer<'de>,
53    {
54        let s: &str = Deserialize::deserialize(deserialiser)?;
55        let (season, time_of_day) = s.split('.').collect_tuple().ok_or_else(|| {
56            D::Error::custom(format!(
57                "Invalid input '{s}': Should be in form season.time_of_day"
58            ))
59        })?;
60        Ok(Self {
61            season: season.into(),
62            time_of_day: time_of_day.into(),
63        })
64    }
65}
66
67impl Serialize for TimeSliceID {
68    fn serialize<S>(&self, serialiser: S) -> std::result::Result<S::Ok, S::Error>
69    where
70        S: serde::Serializer,
71    {
72        serialiser.collect_str(self)
73    }
74}
75
76/// Represents a time slice read from an input file, which can be all
77#[derive(PartialEq, Eq, Hash, Clone, Debug)]
78pub enum TimeSliceSelection {
79    /// All year and all day
80    Annual,
81    /// Only applies to one season
82    Season(Season),
83    /// Only applies to a single time slice
84    Single(TimeSliceID),
85}
86
87impl TimeSliceSelection {
88    /// The [`TimeSliceLevel`] to which this [`TimeSliceSelection`] corresponds
89    pub fn level(&self) -> TimeSliceLevel {
90        match self {
91            Self::Annual => TimeSliceLevel::Annual,
92            Self::Season(_) => TimeSliceLevel::Season,
93            Self::Single(_) => TimeSliceLevel::DayNight,
94        }
95    }
96
97    /// Iterate over the subset of time slices in this selection
98    pub fn iter<'a>(
99        &'a self,
100        time_slice_info: &'a TimeSliceInfo,
101    ) -> Box<dyn Iterator<Item = (&'a TimeSliceID, Year)> + 'a> {
102        let ts_info = time_slice_info;
103        match self {
104            Self::Annual => Box::new(ts_info.iter()),
105            Self::Season(season) => {
106                Box::new(ts_info.iter().filter(move |(ts, _)| ts.season == *season))
107            }
108            Self::Single(ts) => Box::new(iter::once((ts, ts_info.time_slices[ts]))),
109        }
110    }
111
112    /// Iterate over this [`TimeSliceSelection`] at the specified level.
113    ///
114    /// For example, this allows you to iterate over a [`TimeSliceSelection::Season`] at the level
115    /// of either seasons (in which case, the iterator will just contain the season) or time slices
116    /// (in which case it will contain all time slices for that season).
117    ///
118    /// Note that you cannot iterate over a [`TimeSliceSelection`] with coarser temporal granularity
119    /// than the [`TimeSliceSelection`] itself (for example, you cannot iterate over a
120    /// [`TimeSliceSelection::Season`] at the [`TimeSliceLevel::Annual`] level). In this case, the
121    /// function will return `None`.
122    pub fn iter_at_level<'a>(
123        &'a self,
124        time_slice_info: &'a TimeSliceInfo,
125        level: TimeSliceLevel,
126    ) -> Option<Box<dyn Iterator<Item = (Self, Year)> + 'a>> {
127        if level > self.level() {
128            return None;
129        }
130
131        let ts_info = time_slice_info;
132        let iter: Box<dyn Iterator<Item = _>> = match self {
133            Self::Annual => match level {
134                TimeSliceLevel::Annual => Box::new(iter::once((Self::Annual, Year(1.0)))),
135                TimeSliceLevel::Season => Box::new(
136                    ts_info
137                        .seasons
138                        .iter()
139                        .map(|(season, duration)| (season.clone().into(), *duration)),
140                ),
141                TimeSliceLevel::DayNight => Box::new(
142                    ts_info
143                        .time_slices
144                        .iter()
145                        .map(|(ts, duration)| (ts.clone().into(), *duration)),
146                ),
147            },
148            Self::Season(season) => match level {
149                TimeSliceLevel::Season => {
150                    Box::new(iter::once((self.clone(), ts_info.seasons[season])))
151                }
152                TimeSliceLevel::DayNight => Box::new(
153                    ts_info
154                        .time_slices
155                        .iter()
156                        .filter(move |(ts, _)| &ts.season == season)
157                        .map(|(ts, duration)| (ts.clone().into(), *duration)),
158                ),
159                TimeSliceLevel::Annual => unreachable!(),
160            },
161            Self::Single(time_slice) => Box::new(iter::once((
162                time_slice.clone().into(),
163                ts_info.time_slices[time_slice],
164            ))),
165        };
166
167        Some(iter)
168    }
169}
170
171impl From<TimeSliceID> for TimeSliceSelection {
172    fn from(value: TimeSliceID) -> Self {
173        Self::Single(value)
174    }
175}
176
177impl From<Season> for TimeSliceSelection {
178    fn from(value: Season) -> Self {
179        Self::Season(value)
180    }
181}
182
183impl Display for TimeSliceSelection {
184    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
185        match self {
186            Self::Annual => write!(f, "annual"),
187            Self::Season(season) => write!(f, "{season}"),
188            Self::Single(ts) => write!(f, "{ts}"),
189        }
190    }
191}
192
193/// The time granularity for a particular operation
194#[derive(
195    PartialEq, PartialOrd, Copy, Clone, Debug, DeserializeLabeledStringEnum, strum::EnumIter,
196)]
197pub enum TimeSliceLevel {
198    /// Treat individual time slices separately
199    #[string = "daynight"]
200    DayNight,
201    /// Whole seasons
202    #[string = "season"]
203    Season,
204    /// The whole year
205    #[string = "annual"]
206    Annual,
207}
208
209/// Information about the time slices in the simulation, including names and durations
210#[derive(PartialEq, Debug)]
211pub struct TimeSliceInfo {
212    /// Names of times of day (e.g. "evening")
213    pub times_of_day: IndexSet<TimeOfDay>,
214    /// Names and fraction of year occupied by each season
215    pub seasons: IndexMap<Season, Year>,
216    /// The fraction of the year that this combination of season and time of day occupies
217    pub time_slices: IndexMap<TimeSliceID, Year>,
218}
219
220impl Default for TimeSliceInfo {
221    /// The default `TimeSliceInfo` is a single time slice covering the whole year
222    fn default() -> Self {
223        let id = TimeSliceID {
224            season: "all-year".into(),
225            time_of_day: "all-day".into(),
226        };
227        let time_slices = [(id.clone(), Year(1.0))].into_iter().collect();
228
229        Self {
230            seasons: iter::once((id.season, Year(1.0))).collect(),
231            times_of_day: iter::once(id.time_of_day).collect(),
232            time_slices,
233        }
234    }
235}
236
237impl TimeSliceInfo {
238    #[allow(clippy::doc_markdown)]
239    /// Get the `TimeSliceID` corresponding to the `time_slice`.
240    ///
241    /// `time_slice` must be in the form "season.time_of_day".
242    pub fn get_time_slice_id_from_str(&self, time_slice: &str) -> Result<TimeSliceID> {
243        let (season, time_of_day) = time_slice
244            .split('.')
245            .collect_tuple()
246            .context("Time slice must be in the form season.time_of_day")?;
247        let season = self
248            .seasons
249            .get_id(season)
250            .with_context(|| format!("{season} is not a known season"))?;
251        let time_of_day = self
252            .times_of_day
253            .get_id(time_of_day)
254            .with_context(|| format!("{time_of_day} is not a known time of day"))?;
255
256        Ok(TimeSliceID {
257            season: season.clone(),
258            time_of_day: time_of_day.clone(),
259        })
260    }
261
262    /// Get a `TimeSliceSelection` from the specified string.
263    ///
264    /// If the string is empty, the default value is `TimeSliceSelection::Annual`.
265    pub fn get_selection(&self, time_slice: &str) -> Result<TimeSliceSelection> {
266        if time_slice.eq_ignore_ascii_case("annual") {
267            Ok(TimeSliceSelection::Annual)
268        } else if time_slice.contains('.') {
269            let time_slice = self.get_time_slice_id_from_str(time_slice)?;
270            Ok(TimeSliceSelection::Single(time_slice))
271        } else {
272            let season = self
273                .seasons
274                .get_id(time_slice)
275                .with_context(|| format!("'{time_slice}' is not a valid season"))?
276                .clone();
277            Ok(TimeSliceSelection::Season(season))
278        }
279    }
280
281    /// Iterate over all [`TimeSliceID`]s
282    pub fn iter_ids(&self) -> indexmap::map::Keys<'_, TimeSliceID, Year> {
283        self.time_slices.keys()
284    }
285
286    /// Iterate over all time slices
287    pub fn iter(&self) -> impl Iterator<Item = (&TimeSliceID, Year)> {
288        self.time_slices
289            .iter()
290            .map(|(ts, duration)| (ts, *duration))
291    }
292
293    /// Iterate over the different time slice selections for a given time slice level.
294    ///
295    /// For example, if [`TimeSliceLevel::Season`] is specified, this function will return an
296    /// iterator of [`TimeSliceSelection`]s covering each season.
297    pub fn iter_selections_at_level(
298        &self,
299        level: TimeSliceLevel,
300    ) -> Box<dyn Iterator<Item = TimeSliceSelection> + '_> {
301        match level {
302            TimeSliceLevel::Annual => Box::new(iter::once(TimeSliceSelection::Annual)),
303            TimeSliceLevel::Season => {
304                Box::new(self.seasons.keys().cloned().map(TimeSliceSelection::Season))
305            }
306            TimeSliceLevel::DayNight => {
307                Box::new(self.iter_ids().cloned().map(TimeSliceSelection::Single))
308            }
309        }
310    }
311
312    /// Iterate over a subset of time slices calculating the relative duration of each.
313    ///
314    /// The relative duration is specified as a fraction of the total time covered by `selection`.
315    ///
316    /// # Arguments
317    ///
318    /// * `selection` - A subset of time slices
319    ///
320    /// # Returns
321    ///
322    /// An iterator of time slices along with the fraction of the total selection.
323    pub fn iter_selection_share<'a>(
324        &'a self,
325        selection: &'a TimeSliceSelection,
326        level: TimeSliceLevel,
327    ) -> Option<impl Iterator<Item = (TimeSliceSelection, Dimensionless)> + use<>> {
328        // Store selections as we have to iterate twice
329        let selections = selection.iter_at_level(self, level)?.collect_vec();
330
331        // Total duration covered by selection
332        let total_duration: Year = selections.iter().map(|(_, duration)| *duration).sum();
333
334        // Calculate share
335        let iter = selections
336            .into_iter()
337            .map(move |(selection, duration)| (selection, duration / total_duration));
338        Some(iter)
339    }
340
341    /// Share a value between a subset of time slices in proportion to their lengths.
342    ///
343    /// For instance, you could use this function to compute how demand is distributed between the
344    /// different time slices of winter.
345    ///
346    /// # Arguments
347    ///
348    /// * `selection` - A subset of time slices
349    /// * `value` - The value to be shared between the time slices
350    ///
351    /// # Returns
352    ///
353    /// An iterator of time slices along with a fraction of `value`.
354    pub fn calculate_share<'a>(
355        &'a self,
356        selection: &'a TimeSliceSelection,
357        level: TimeSliceLevel,
358        value: Dimensionless,
359    ) -> Option<impl Iterator<Item = (TimeSliceSelection, Dimensionless)> + use<>> {
360        let iter = self
361            .iter_selection_share(selection, level)?
362            .map(move |(selection, share)| (selection, value * share));
363        Some(iter)
364    }
365}
366
367#[cfg(test)]
368mod tests {
369    use super::*;
370    use crate::units::UnitType;
371    use itertools::assert_equal;
372    use rstest::{fixture, rstest};
373
374    #[fixture]
375    fn time_slices1() -> [TimeSliceID; 2] {
376        [
377            TimeSliceID {
378                season: "winter".into(),
379                time_of_day: "day".into(),
380            },
381            TimeSliceID {
382                season: "summer".into(),
383                time_of_day: "night".into(),
384            },
385        ]
386    }
387
388    #[fixture]
389    fn time_slice_info1(time_slices1: [TimeSliceID; 2]) -> TimeSliceInfo {
390        TimeSliceInfo {
391            seasons: [("winter".into(), Year(0.5)), ("summer".into(), Year(0.5))]
392                .into_iter()
393                .collect(),
394            times_of_day: ["day".into(), "night".into()].into_iter().collect(),
395            time_slices: time_slices1.map(|ts| (ts, Year(0.5))).into_iter().collect(),
396        }
397    }
398
399    #[fixture]
400    fn time_slice_info2() -> TimeSliceInfo {
401        let time_slices = [
402            TimeSliceID {
403                season: "winter".into(),
404                time_of_day: "day".into(),
405            },
406            TimeSliceID {
407                season: "winter".into(),
408                time_of_day: "night".into(),
409            },
410            TimeSliceID {
411                season: "summer".into(),
412                time_of_day: "day".into(),
413            },
414            TimeSliceID {
415                season: "summer".into(),
416                time_of_day: "night".into(),
417            },
418        ];
419        TimeSliceInfo {
420            times_of_day: ["day".into(), "night".into()].into_iter().collect(),
421            seasons: [("winter".into(), Year(0.5)), ("summer".into(), Year(0.5))]
422                .into_iter()
423                .collect(),
424            time_slices: time_slices
425                .iter()
426                .map(|ts| (ts.clone(), Year(0.25)))
427                .collect(),
428        }
429    }
430
431    #[rstest]
432    fn test_ts_selection_iter_annual(
433        time_slice_info1: TimeSliceInfo,
434        time_slices1: [TimeSliceID; 2],
435    ) {
436        assert_equal(
437            TimeSliceSelection::Annual.iter(&time_slice_info1),
438            time_slices1.iter().map(|ts| (ts, Year(0.5))),
439        );
440    }
441
442    #[rstest]
443    fn test_ts_selection_iter_season(
444        time_slice_info1: TimeSliceInfo,
445        time_slices1: [TimeSliceID; 2],
446    ) {
447        assert_equal(
448            TimeSliceSelection::Season("winter".into()).iter(&time_slice_info1),
449            iter::once((&time_slices1[0], Year(0.5))),
450        );
451    }
452
453    #[rstest]
454    fn test_ts_selection_iter_single(
455        time_slice_info1: TimeSliceInfo,
456        time_slices1: [TimeSliceID; 2],
457    ) {
458        let ts = time_slice_info1
459            .get_time_slice_id_from_str("summer.night")
460            .unwrap();
461        assert_equal(
462            TimeSliceSelection::Single(ts).iter(&time_slice_info1),
463            iter::once((&time_slices1[1], Year(0.5))),
464        );
465    }
466
467    fn assert_selection_equal<I, T>(actual: Option<I>, expected: Option<Vec<(&str, T)>>)
468    where
469        T: UnitType,
470        I: Iterator<Item = (TimeSliceSelection, T)>,
471    {
472        let Some(actual) = actual else {
473            assert!(expected.is_none());
474            return;
475        };
476
477        let ts_info = time_slice_info2();
478        let expected = expected
479            .unwrap()
480            .into_iter()
481            .map(move |(sel, frac)| (ts_info.get_selection(sel).unwrap(), frac));
482        assert_equal(actual, expected);
483    }
484
485    #[rstest]
486    #[case(TimeSliceSelection::Annual, TimeSliceLevel::Annual, Some(vec![("annual", Year(1.0))]))]
487    #[case(TimeSliceSelection::Annual, TimeSliceLevel::Season, Some(vec![("winter", Year(0.5)), ("summer", Year(0.5))]))]
488    #[case(TimeSliceSelection::Annual, TimeSliceLevel::DayNight,
489           Some(vec![("winter.day", Year(0.25)), ("winter.night", Year(0.25)), ("summer.day", Year(0.25)), ("summer.night", Year(0.25))]))]
490    #[case(TimeSliceSelection::Season("winter".into()), TimeSliceLevel::Annual, None)]
491    #[case(TimeSliceSelection::Season("winter".into()), TimeSliceLevel::Season, Some(vec![("winter", Year(0.5))]))]
492    #[case(TimeSliceSelection::Season("winter".into()), TimeSliceLevel::DayNight,
493           Some(vec![("winter.day", Year(0.25)), ("winter.night", Year(0.25))]))]
494    #[case(TimeSliceSelection::Single("winter.day".into()), TimeSliceLevel::Annual, None)]
495    #[case(TimeSliceSelection::Single("winter.day".into()), TimeSliceLevel::Season, None)]
496    #[case(TimeSliceSelection::Single("winter.day".into()), TimeSliceLevel::DayNight, Some(vec![("winter.day", Year(0.25))]))]
497    fn test_ts_selection_iter_at_level(
498        time_slice_info2: TimeSliceInfo,
499        #[case] selection: TimeSliceSelection,
500        #[case] level: TimeSliceLevel,
501        #[case] expected: Option<Vec<(&str, Year)>>,
502    ) {
503        let actual = selection.iter_at_level(&time_slice_info2, level);
504        assert_selection_equal(actual, expected);
505    }
506
507    #[rstest]
508    #[case(TimeSliceSelection::Annual, TimeSliceLevel::Annual, Some(vec![("annual", Dimensionless(8.0))]))]
509    #[case(TimeSliceSelection::Annual, TimeSliceLevel::Season, Some(vec![("winter", Dimensionless(4.0)), ("summer", Dimensionless(4.0))]))]
510    #[case(TimeSliceSelection::Annual, TimeSliceLevel::DayNight,
511           Some(vec![("winter.day", Dimensionless(2.0)), ("winter.night", Dimensionless(2.0)), ("summer.day", Dimensionless(2.0)), ("summer.night", Dimensionless(2.0))]))]
512    #[case(TimeSliceSelection::Season("winter".into()), TimeSliceLevel::Annual, None)]
513    #[case(TimeSliceSelection::Season("winter".into()), TimeSliceLevel::Season, Some(vec![("winter", Dimensionless(8.0))]))]
514    #[case(TimeSliceSelection::Season("winter".into()), TimeSliceLevel::DayNight,
515           Some(vec![("winter.day", Dimensionless(4.0)), ("winter.night", Dimensionless(4.0))]))]
516    #[case(TimeSliceSelection::Single("winter.day".into()), TimeSliceLevel::Annual, None)]
517    #[case(TimeSliceSelection::Single("winter.day".into()), TimeSliceLevel::Season, None)]
518    #[case(TimeSliceSelection::Single("winter.day".into()), TimeSliceLevel::DayNight, Some(vec![("winter.day", Dimensionless(8.0))]))]
519    fn test_calculate_share(
520        time_slice_info2: TimeSliceInfo,
521        #[case] selection: TimeSliceSelection,
522        #[case] level: TimeSliceLevel,
523        #[case] expected: Option<Vec<(&str, Dimensionless)>>,
524    ) {
525        let actual = time_slice_info2.calculate_share(&selection, level, Dimensionless(8.0));
526        assert_selection_equal(actual, expected);
527    }
528}