choicelogics

This Code is a practical implementation of Bernreiter, Michael, Jan Maly, and Stefan Woltran. "Choice logics and their computational properties." Artificial Intelligence 311 (2022): 103755 This npm package provides a general framework for choice logics. It offers a flexible and extensible foundation for preference modeling and reasoning, encapsulating various choice logics, including Qualitative Choice Logic (QCL) and Conjunctive Choice Logic (CCL), while allowing the definition of new ones.

Installation

To install the package, use npm:

npm install choicelogics

Usage

Importing the Module

import { QCCL, PropositionalLogic, ChoiceResult, normalizeChoiceResult, choiceResultToBool, boolToChoiceResult, validateChoiceResult } from "choicelogics";

Example

const a: ChoiceResult = { degree: 2, optionality: 1 };
const b: ChoiceResult = { degree: Infinity, optionality: 2 };

const result1 = QCCL.orderedDisjunction(a, b);
console.log(result1); // { degree: 2, optionality: 3 }

const result2 = PropositionalLogic.and(a, b);
console.log(result2); // { degree: Infinity, optionality: 2 }

const boolResult = choiceResultToBool(a);
console.log(boolResult); // true

const choiceResult = boolToChoiceResult(false);
console.log(choiceResult); // { degree: Infinity, optionality: 1 }

const isValid = validateChoiceResult(a);
console.log(a) // true

API

Classes

QCCL (Extends PropositionalLogic)

A combination of QCL and CCL

• static orderedDisjunction(a: ChoiceResult, b: ChoiceResult): ChoiceResult
• static orderedConjunction(a: ChoiceResult, b: ChoiceResult): ChoiceResult

PropositionalLogic

• static and(a: ChoiceResult, b: ChoiceResult): ChoiceResult
• static or(a: ChoiceResult, b: ChoiceResult): ChoiceResult
• static negation(a: ChoiceResult): ChoiceResult

Types

ChoiceResult

type ChoiceResult = {
  degree: number;
  optionality: number;
};

ConnectiveFunction

type ConnectiveFunction = (a: ChoiceResult, b: ChoiceResult) => ChoiceResult;

ModifierFunction

type ModifierFunction = (a: ChoiceResult) => ChoiceResult;

ConnectMultipleFunction

type ConnectMultipleFunction = (...args: ChoiceResult[]) => ChoiceResult;

Util Functions

normalizeChoiceResult(result: ChoiceResult): ChoiceResult

boolToChoiceResult(value: boolean): ChoiceResult

choiceResultToBool(result: ChoiceResult): boolean

validateChoiceResult(result: ChoiceResult): boolean

Extending the Logic

You can extend the existing logic by inheriting from the provided classes and using the function types ConnectiveFunction, ModifierFunction, and ConnectMultipleFunction. Here is an example of how to create a new logic class by extending PropositionalLogic:

import { PropositionalLogic, ChoiceResult, ConnectiveFunction, ModifierFunction } from "choicelogics";

class CustomLogic extends PropositionalLogic {
  public static customOperation: ConnectiveFunction = (a, b) => {
    // Custom logic implementation
    return {
      degree: a.degree + b.degree,
      optionality: a.optionality * b.optionality,
    };
  };

  public static customModifier: ModifierFunction = (a) => {
    // Custom modifier logic
    return {
      degree: a.degree * 2,
      optionality: a.optionality * 2,
    };
  };
}

const a: ChoiceResult = { degree: 2, optionality: 1 };
const b: ChoiceResult = { degree: 3, optionality: 2 };

const result = CustomLogic.customOperation(a, b);
console.log(result); // { degree: 5, optionality: 2 }

const modifierResult = CustomLogic.customModifier(a);
console.log(negationResult); // { degree: 4, optionality: 2 }

License

This project is licensed under the ISC License.