Tiny swiss pairing library with basic deterministic functionality
npm install swiss-pairing
swiss-pairing is a tiny swiss pairing library with basic deterministic functionality
* npm install --save swiss-pairing
* require('swiss-pairing')(options)
* options contains the following variables:
* maxPointsPerRound - the number of points a participant can score in a
round - usually 1 or 2
* default: 1
* rematchWeight - rematch penalty weight
* default: 100
* standingPower - the power to which standings differences should be
raised
* default: 2
* seedMultiplier - the deterministic PRNG seed multiplier, ideally a prime
of at least 4 digits
* default: 6781
* See test/test.js for usage example
swiss-pairing exposes the following three methods:
See participants and matches formats below.
Determines the matchups for the given round by pairing participants:
* who have not faced each other
* in order of:
* highest standing to lowest
* highest modified median score to lowest
* lowest seed to highest
* where the highest ranked team in a pair is given the home side
When byes are needed (in the case of an odd number of participants), they bubble
up from the lowest to the highest ranking, (starting with the lowest seed when
no match history is available). participants cannot have more than one bye.
Matchups returned are in the form:
``javascript`
[
{
'home': home_participant_id,
'away': away_participant_id
},
...
]
See participants and matches formats below.
Determines the standings for a given round by accumulating won points and lost
points and calculating modified median scores. Standings are ordered by wins,
modified median score, and (inverse) seed in that order.
Standings returned are in the form:
`javascript`
[
{
'id': participant_id,
'seed': seed,
'wins': won_points,
'losses': lost_points,
'tiebreaker': modified_median_score
},
...
]
See participants and matches formats below.
Caculates modified median scores based on the given participants and paired
match history.
Scores returned are in the form:
`javascript`
{
...
}
The participants argument expects an array in the form:
`javascript`
[
{
'id': participant_id,
'seed': participant_seed
}
]
* participant_id may be any value that exposes a toString method (and canparticipant_seed
therefore be used as a key on a javascript object)
* may be any directly sortable unique value, although numeric values (1..N)
are suggested for reliability
The matches argument expects an array in the form:
`javascript`
[
{
'round': match_round,
'home': {
'id': home_participant_id,
'points': home_won_points
},
'away': {
'id': away_participant_id,
'points': away_won_points
}
}
]
* match_round must be a value sortable against the given currentRound
argument - all will be limited to those where the round is less thancurrentRound
the
* and away_participant_id may be any values thatteams
javascript is capable of using as an object key and must exist in the given argumenthome_points_won
and away_points_won should* be numeric values, but0 + ...
currently can be anything that can be accumulated against and comparedmaxPerRound
against numeric values - there are also no checks against whether or not these
values overrun and any data that does overrun maxPerRound` will
likely result in strange or erroneous results from every function in this
library