Create my own elimination rule

1. What an elimination rule is

A rule is a grid, written like the federations' tables, for one discipline and one number of laps:

• one column per number of starters: "8" for exactly eight athletes, "12-14" for twelve to fourteen;
• one row per lap, from lap 1 to the finish; the elimination laps are ticked;
• in each cell of an elimination lap: the number of athletes who remain in the race after that lap (not those who go out: that is how federations write it, and it is what lets one column serve several numbers of starters);
• the lap before an elimination lap is the bell lap;
• the last row is the finish: never an elimination on the final lap.

Here is the HSK rule, as FINISH shows it:

Reading the "15-16" column: 13 athletes remain after lap 4, 11 after lap 6, then 9, 8, 7 and 6 at the finish. The "12-14" column leaves 11, 10, 9, 8, 7 then 6 athletes. With 10 or 11 starters, no column applies.

2. How FINISH calculates the formula

A race keeps only the name of the rule. At the start, and not before, FINISH:

1. counts the starters: the race's active athletes (a skater deactivated before the start does not count);
2. looks for the column that covers that number; if there is none, the race runs without elimination;
3. goes down the ticked laps, keeping count of the athletes in the race, and writes the race's formula: "4:2" when two athletes go out at the end of lap 4, "6" when only one goes out at the end of lap 6.

Here is the FINISH function that does this calculation (GrilleElimination.Formule), as it is:

public string Formule(int partants)
{
    if (ColonnePour(partants) is not { } colonne) return "";
    var etapes = new List<string>();
    var enCourse = partants;
    for (var i = 0; i < Tours.Count && i < colonne.Restants.Count; i++)
    {
        if (colonne.Restants[i] is not { } restants || restants >= enCourse || restants < 1) continue;
        var sortants = enCourse - restants;
        etapes.Add(sortants == 1
            ? Tours[i].ToString(CultureInfo.InvariantCulture)
            : string.Create(CultureInfo.InvariantCulture, $"{Tours[i]}:{sortants}"));
        enCourse = restants;
    }
    return string.Join("; ", etapes);
}

In simple words (the code's names are French: partants = starters, enCourse = in the race, restants = remaining, sortants = going out):

• ColonnePour(partants): the first column whose range contains the number of starters. None: the formula is empty.
• enCourse starts at the number of starters.
• For each ticked lap, the column's cell (restants) is skipped if it is empty, if it is 0, or if it is not smaller than enCourse (nobody to take out).
• Otherwise, sortants = enCourse − restants; the step is written "lap" for one athlete going out, "lap:number" for several; and enCourse becomes restants.
• The steps are joined with "; ".

Example with the HSK rule and 14 starters ("12-14" column):

Formula: 4:3; 6; 8; 10; 12; 14, six athletes at the finish. With 12 starters, the same column gives 4; 6; 8; 10; 12; 14: on lap 4, 12 → 11, only one goes out. That is the whole point of writing the remaining: a "12-14" column always leads to the same number of athletes at the finish, whatever the starting number. The editor and the rules window show this calculation for every number of starters covered:

3. The rules window

SessionElimination rules… (also Settings › Files and tracks, and the … button next to the rule list of a favourite or a race sheet) shows the rules of the session's discipline: the federation's (blue chip, read-only: View grid… and Duplicate) and yours (amber chip My rules: New rule, Edit, Delete). Full description: the reference.

4. Example A: duplicate the HSK rule and adjust it for 10 to 16 starters

The CLAP club's need: keep the HSK rule as it is from 12 to 16 starters, and also eliminate when there are 10 or 11, with five skaters left for the final sprint.

1. Open the window on 16 laps

   In SessionFavourite races…, choose the favourite "Élimination 16 tours" (16 laps of 111.12 m) and click … next to Elimination rule: the window opens filtered on 16 laps.

2. Choose the HSK rule, Duplicate

   Choose "HSK Élimination 16 tours" (Federation chip), then Duplicate. The editor opens on a copy named "HSK Élimination 16 tours (copy)", with the same grid.

   Lap	Starters →	12-14	15-16
   1		12-14	15-16
   2		12-14	15-16
   3	Bell	12-14	15-16
   4	Elimination	11	13
   5	Bell	11	13
   6	Elimination	10	11
   7	Bell	10	11
   8	Elimination	9	9
   9	Bell	9	9
   10	Elimination	8	8
   11	Bell	8	8
   12	Elimination	7	7
   13	Bell	7	7
   14	Elimination	6	6
   15		6	6
   16	Finish — no elimination	6	6

3. Rename

   In Rule name, write "CLAP Élimination 16 tours". If you kept the name "HSK Élimination 16 tours", Confirm would refuse it: the race keeps only the name, which must be unique for 16 laps in the discipline.

4. Add the "10-11" column

   Add a column: an empty column appears on the right. Write "10-11" in its header and press Enter: the cursor moves down to its lap 4 cell.

5. Enter the remaining

   Write 9, Enter, 8, Enter, 7, Enter, 6, Enter, 5, and leave the lap 14 cell empty: with so few starters, the club does not want an elimination on lap 14. The rows in italics fill in by themselves (9 on lap 5, 8 on lap 7…).

   Below the grid, two new lines: "10 starters: 4; 6; 8; 10; 12 → 5 at the finish" and "11 starters: 4:2; 6; 8; 10; 12 → 5 at the finish".

6. Confirm

   Confirm. The grid has no error: the rule is saved in your rules, with the columns in increasing order ("10-11" will be the first the next time it opens).

   "Rule "CLAP Élimination 16 tours" added to your rules (16 laps)." The rule appears with the My rules chip, and immediately in the favourite's list.

Before / after, what the rule will do depending on the number of starters:

The race, lap by lap (11 starters)

Race "Élimination 16 tours Femmes", 16 laps, rule "CLAP Élimination 16 tours". Twelve entries; Rosalie Duquerroy (PRJ), who is ill, is deactivated before the start: 11 starters. The bells are set to ring on this computer and to be broadcast to VOICE (Settings); the race has Speech synthesis.

What each program shows at the end of lap 4:

The final ranking:

5. Example B: create "an elimination every 2 laps" over 12 laps from scratch

For Tuesday training, the club wants a 12-lap race where one skater goes out every two laps, for 7 to 10 starters.

1. New rule

   In the rules window, set the Number of laps filter to All then New rule. Name: "CLAP Tous les 2 tours"; Number of laps: 12, Enter (proposed: 10 with no filter and no race of origin). The grid has 12 rows; the last one says "Finish — no elimination".

2. Tick every other lap

   Tick every other lap (2, 4, 6…) ticks 2, 4, 6, 8 and 10 (not 12: it is the finish). Rows 1, 3, 5, 7 and 9 show "Bell" in italics.

3. One column per number of starters

   Add four columns: "7", "8", "9" and "10". Why not a single "7-10" column? Because a cell gives those who remain: the same number cannot take out exactly one skater each time for 7 and for 10 starters (see the trap below).

4. The remaining

   In each column, one fewer on each ticked lap: "7": 6, 5, 4, 3, 2; "8": 7, 6, 5, 4, 3; "9": 8, 7, 6, 5, 4; "10": 9, 8, 7, 6, 5.

   The formula is "2; 4; 6; 8; 10" for each number of starters, with 2, 3, 4 or 5 skaters at the finish.

5. Confirm

   The rule joins your rules. Choose it in a 12-lap favourite (a 12-lap rule is only offered to 12-lap races, or 11.5-lap races, rounded up to 12).

The race, lap by lap (8 starters)

Training "Élimination 12 tours Hommes", 8 starters: the "8" column gives 2; 4; 6; 8; 10, three skaters at the finish.

6. Example C: a number of starters that no column covers

The following week, "Élimination 16 tours Femmes" with the rule "CLAP Élimination 16 tours" (columns 10-11, 12-14, 15-16). Two entries do not show up: they are deactivated and 9 starters remain.

What happens

• Before the start, nothing warns you: the favourite and the sheet do not know the number of starters yet. The banner only says that the formula will be determined at the start.
• At the start, the log writes: "Elimination rule "CLAP Élimination 16 tours": nothing defined for 9 starter(s), the race runs without elimination."
• During the race: no elimination bell, nobody is eliminated; the 9 skaters do all 16 laps. Only the last-lap bell rings, if it is in use.

The same with 17 starters, or with the HSK rule and 10 or 11 starters.

Fixing it before the race

1. Add the missing column

   In the rules window, choose "CLAP Élimination 16 tours" then Edit. Add a column, header "8-9", cells 7, 6, 5, 4 on laps 4, 6, 8 and 10; leave laps 12 and 14 empty.

   "8 starters: 4; 6; 8; 10 → 4 at the finish" and "9 starters: 4:2; 6; 8; 10 → 4 at the finish".

2. Confirm

   "Rule "CLAP Élimination 16 tours" saved." The name does not change: the favourites and races that name it benefit from the fix.

3. Load the race after the fix

   FINISH reads the grid when the race is loaded into a tab. A race already loaded keeps the earlier grid: send it back to the list (Next: before the start, without confirmation; its order moves on by the increment set in Settings) then load it again.

The race has already started

The formula is set at the start; changing the rule no longer changes this race. To apply the planned elimination anyway, do it by hand: Ring the bell (the race's Bell tab) one lap before, then, at the end of the lap, select the last skater in the ranking and click Eliminate (referee's decision: "Élimination 16 tours Femmes: … eliminated."). VOICE announces the elimination; a bell rung by hand is not followed by the phrase "At the end of the next lap…".

7. Linking the rule to a favourite and to a race sheet

In the favourite races and the race sheet, the Elimination rule list offers "(no rule: free formula)" then the rules of the session's discipline and of the race's number of laps, the federation's and yours, under their name. The … button opens the rules window on that number of laps; when it closes, the list is read again.

1. The list of rules and the … button.
2. The rule read back in plain words ("Your rule" for one of yours, "Rule" for the federation's), then the rule's table. In red: "Rule "…" is made for 16 laps, not 15." or "Rule "…" is not known on this station (shared data to update?). The race will run without elimination."

1. The favourite

   SessionFavourite races…: "Élimination 16 tours", check Number of laps = 16, choose "CLAP Élimination 16 tours", Save.

2. The race sheet

   In the sheet of "Élimination 16 tours Femmes", Use the favourite, or choose the rule in the list. The Elimination field (free formula) is emptied and greyed out: the rule will decide, at the start.

8. What the shared-data update guarantees

The shared-data update (at start-up, or HelpUpdate shared data…) brings the federation's new rules and new versions of its own. For yours:

• they are kept: the update deletes nothing and never writes over one of your rules;
• they are never published: they stay in this computer's database (and that of the computers sharing it);
• they keep their name: your favourites and races keep finding them;
• a copy does not follow the original: if HSK changes its rule, "CLAP Élimination 16 tours" does not change.

If the federation later publishes a rule with the same name as one of yours (same discipline, same number of laps), it arrives anyway, and yours is the one that applies; the window points it out in amber below your rule. Rename yours to be able to choose the federation's.

9. FAQ: the traps

The rule is not in the favourite's or sheet's list.

The list only offers the rules for the race's number of laps (rounded up: 13.5 laps → 14-lap rules) and the session's discipline. Check both (SessionSession configuration…), or create the rule for that number of laps.

"Rule "…" is made for 16 laps, not 15."

The race's number of laps changed after the rule was chosen. Set it back, or choose a rule with this number of laps.

"Rule "…" is not known on this station…"

A federation rule not received yet (update the shared data), one of your rules deleted, or created on a computer that does not share the same database.

I wrote the number of athletes going out.

The cells give those who remain. The symptom: "… remaining is more than before" or a strange formula. With 14 starters, "3" on lap 4 would mean "3 remain", i.e. 11 eliminated at once.

A "7-10" column does not eliminate on the first ticked lap.

A cell that is not smaller than the number in the race takes nobody out. See the trap in Example B.

I changed the rule, the race did not change.

The grid is read when the race is loaded and the formula is set at the start. A race already loaded, started or run keeps what it had; a race read back from the database keeps its formula.

Who counts as a starter?

The athletes active at the moment of the start. Deactivating someone after the start does not change the formula.

A skater falls and has not completed the elimination lap.

FINISH waits for everyone. If the leader crosses the line again while some skaters have not completed the lap, those go out first. If the leader is already two laps ahead of the elimination lap, the step is abandoned.

An eliminated skater put back in the race (Eliminate button on her).

She resumes the race; the step that took her out is not replayed: there will be one more skater at the finish.

A bell rung just before the elimination bell.

Two bells are at least the minimum time between two bells apart. An elimination bell that falls within this delay (manual bell, another athlete's last-lap bell) is not lost: it rings as soon as the delay ends, if the leader has not yet completed the elimination lap.

A ticked lap 1 has no bell.

There is no lap before lap 1. For lap 2, the bell rings when the leader crosses the line at the end of lap 1.

Nothing happens in a relay or team race.

Automatic elimination only applies to a race of type Individual.

My rule's table is in French while FINISH is in English.

The image is drawn on confirmation, in the interface language of that moment. Open the rule again and confirm it again in the other language.

Deleting one of my rules.

The favourites and races that name it no longer have a rule and run without elimination, unless another rule has that name for that number of laps. FINISH reminds you before deleting.

10. Summary