An implementation of the Hare-Niemeyer (also known as Hamilton or largest remainder) method. Parliament seat allocation algorithm used in multiple countries around the world.
Attention: Since some countries use a modification of the algorithm instead of this vanilla version, you should check your country's electoral legislature. Furthermore, I don't take any responsibility for the accuracy of the calculated numbers, even though I'm pretty confident with my implementation.
npm install hare-niemeyer
This package is ESM only.
import hareNiemeyer from 'hare-niemeyer'
const electionResults = { // number of votes per party
socialists: 130755,
conservatives: 102068,
liberals: 34012,
greens: 31090,
crazypeople: 11111
}
const seats = 420 // number of seats to be distributed
const parliament = hareNiemeyer(electionResults, seats, draw=true)
The parliament
variable will look like this:
{
"socialists": 178,
"conservatives": 139,
"liberals": 46,
"greens": 42,
"crazypeople": 15
}
The draw
option changes the behaviour of the algorithm in case of equal quota remainders for multiple parties. Usually, in this case the elections administrator would draw by lot which party gets the remaining seat. The script does this for you if the draw
option is true
or not set at all (default behaviour). If you change the option to false
, the script will return the raw quotas for the involved parties instead:
const electionResults = { // number of votes per party
socialists: 10,
conservatives: 15,
liberals: 1,
greens: 4
}
const seats = 100 // number of seats to be distributed
const parliament = hareNiemeyer(electionResults, seats, false)
In this case, the parliament
variable looks like this:
{
"socialists": 33.333333333333,
"conservatives": 50,
"liberals": 3.333333333333,
"greens": 13.333333333333
}
- sainte-lague - Sainte-Laguë / Webster / Schepers method
- DHondt – D'Hondt method
If you found a bug or want to propose a feature, feel free to visit the issues page.