electre-js

ELECTRE is a set of multi-criteria decision analysis methods.
If you've never heard of these methods, you can have a look at this document from José Rui FIGUEIRA.

You can use this package in your Node.js and / or web projects.
It uses Workers to calculate results in a separated thread.

Implemented methods

Algorithms come from J-Electre.

Methods for choosing

• [x] ELECTRE I
• [ ] ELECTRE Is (Seuil)
• [ ] ELECTRE Iv (Veto)

Methods for ranking

• [ ] ELECTRE II
• [ ] ELECTRE III
• [ ] ELECTRE IV

Methods for ordinal classification or sorting

• [ ] ELECTRE TRI
• [ ] ELECTRE TRI ME (Multi-Evaluator)

Only checked methods are implemented at this time, I'll slowly implement the others but tell me if you want to focus on a particular one.

Web version

If you want to use this package in its web version and are using a bundler, you'll have to manually copy web workers.

Example with Spike SSG

By using copy-webpack-plugin in your app.js:

const CopyWebpackPlugin = require('copy-webpack-plugin')
const path = require('path')

module.exports = {
  // ...
  afterSpikePlugins: [
    new CopyWebpackPlugin([{
      from: path.resolve(__dirname, 'node_modules/electre-js/lib/workers'),
      to: path.resolve(__dirname, 'public/workers')
    }])
  ]
}

API

How to use

import electre from 'electre-js';

where electre is an object with two methods : start & kill as described bellow.
You can only run one calculation at a time.

electre.start(version, inputData)

Set calculator state to busy (electre._idle = false) and send a message to related worker that will handle calculation. Throws an error if calculator isn't idle.

inputData

An object with following properties :

| properties | mandatory | expected in methods | type | rules | |-------------------------|-------------|-----------------------|-------------------------------|-----------------------------------------------------------------------------------| | numberOfCriterias | true | I | number | > 0 | | numberOfAlternatives | true | I | number | > 1 | | criterias | true | I | array of strings | size = numberOfCriterias, all values are unique, no undefined | | weights | true | I | array of numbers | size = size of criterias, no undefined | | alternatives | true | I | array of strings | size = numberOfAlternatives, all values are unique, no undefined | | evaluations | true | I | array of arrays of numbers | matrix n * p where n = size of alternatives & p = size of criterias, no undefined | | cThreshold | true | I | number | 0 < value < 1 | | dThreshold | true | I | number | 0 < value < 1 |

returns

A promise of an object with following properties :

| properties | type | rules | returned in methods | |--------------|------------------------------|-------------------------------------------------------------------|-----------------------| | inputData | object | inputData passed to the worker | I | | concordance | array of arrays of numbers | square matrix n * n where n = alternatives size | I | | discordance | array of arrays of numbers | square matrix n * n where n = alternatives size | I | | credibility | array of arrays of numbers | square matrix n * n where n = alternatives size. Values = 0 or 1 | I | | kernel | array of strings | partition of alternatives | I | | dominated | array of strings | partition of alternatives | I |

electre.kill()

Ask to terminate busy worker and set calculator state back to idle (electre._idle = true).
Promise returned when electre.start() is rejected.

Demo

On electre-www, you can discover electre-js and use ELECTRE methods

Credits

Algorithms come from J-Electre.