cbrlib 2.0.2

Case Based Reasoning library for Python

Case Based Reasoning the Pythonic Way

Case Based Reasoning library for Python

This library provides the possibility to integrate with native python. Basic implemetation can use instances of Python classes to calculate similarity between those objects.

import dataclasses
import functools
from typing import Optional

from cbrlib import casebase, evaluate
from cbrlib.evaluate import (
    Evaluator,
    NumericEvaluationOptions,
    WeightedPropertyEvaluatorMapping,
    FunctionCalculationParameter,
)
from cbrlib.types import ReasoningRequest


@dataclasses.dataclass(slots=True, frozen=True)
class DataObject:
    color: Optional[str] = None
    shape: Optional[str] = None
    size: Optional[int] = None


color_lookup = {
    "red": {"red": 1, "orange": 0.8, "yellow": 0.4},
    "orange": {"orange": 1, "red": 0.8, "yellow": 0.8},
}
color_evaluator = functools.partial(evaluate.table_lookup, color_lookup)


def create_size_evaluator() -> Evaluator:
    options = NumericEvaluationOptions(
        min_=0,
        max_=100,
        if_less=FunctionCalculationParameter(tolerance=1.0),
        if_more=FunctionCalculationParameter(tolerance=1.0),
    )
    return functools.partial(evaluate.numeric, options)


def dataobject_evaluator() -> Evaluator:
    mappings = (
        WeightedPropertyEvaluatorMapping("color", color_evaluator, 2),
        WeightedPropertyEvaluatorMapping("size", create_size_evaluator(), 1),
        WeightedPropertyEvaluatorMapping("shape", evaluate.equality, 1),
    )
    return functools.partial(evaluate.case_average, mappings)


def main() -> None:
    data = [
        DataObject(color="red", shape="triangle", size=20),
        DataObject(color="orange", shape="circle", size=70),
        DataObject(color="green", shape="square", size=50),
    ]
    print("-" * 80)
    print(
        casebase.infer(
            data,
            ReasoningRequest(
                query=DataObject(color="red"),
            ),
            dataobject_evaluator(),
        )
    )
    print("-" * 80)
    print(
        casebase.infer(
            data,
            ReasoningRequest(
                query=DataObject(size=50),
            ),
            dataobject_evaluator(),
        )
    )