评估()

Run the evaluation on the dataset with different metrics

Parameters:

Name	Type	Description	Default
dataset	Dataset[question:list[str], contexts:list[list[str]], answer:list[str], ground_truth:list[list[str]]]	The dataset in the format of ragas which the metrics will use to score the RAG pipeline with	required
metrics	list[Metric]	List of metrics to use for evaluation. If not provided then ragas will run the evaluation on the best set of metrics to give a complete view.	None
llm	Optional[BaseRagasLLM | BaseLanguageModel]	The language model to use for the metrics. If not provided then ragas will use the default language model for metrics which require an LLM. This can we overridden by the llm specified in the metric level with metric.llm.	None
embeddings	Optional[BaseRagasEmbeddings | Embeddings]	The embeddings to use for the metrics. If not provided then ragas will use the default embeddings for metrics which require embeddings. This can we overridden by the embeddings specified in the metric level with metric.embeddings.	None
callbacks	Callbacks	Lifecycle Langchain Callbacks to run during evaluation. Check the langchain documentation for more information.	None
in_ci	bool	Whether the evaluation is running in CI or not. If set to True then some metrics will be run to increase the reproducability of the evaluations. This will increase the runtime and cost of evaluations. Default is False.	False
run_config	RunConfig	Configuration for runtime settings like timeout and retries. If not provided, default values are used.	RunConfig()
token_usage_parser	Optional[TokenUsageParser]	Parser to get the token usage from the LLM result. If not provided then the the cost and total tokens will not be calculated. Default is None.	None
raise_exceptions	bool	Whether to raise exceptions or not. If set to True then the evaluation will raise an exception if any of the metrics fail. If set to False then the evaluation will return np.nan for the row that failed. Default is False.	False
column_map	dict[str, str]	The column names of the dataset to use for evaluation. If the column names of the dataset are different from the default ones then you can provide the mapping as a dictionary here. Example: If the dataset column name is contexts_v1, column_map can be given as {"contexts":"contexts_v1"}	None
show_progress	bool	Whether to show the progress bar during evaluation. If set to False, the progress bar will be disabled. Default is True.	True

Returns:

Type	Description
Result	Result object containing the scores of each metric. You can use this do analysis later.

Raises:

Type	Description
ValueError	if validation fails because the columns required for the metrics are missing or if the columns are of the wrong format.

Examples:

the basic usage is as follows:

from ragas import evaluate

>>> dataset
Dataset({
    features: ['question', 'ground_truth', 'answer', 'contexts'],
    num_rows: 30
})

>>> result = evaluate(dataset)
>>> print(result)
{'context_precision': 0.817,
'faithfulness': 0.892,
'answer_relevancy': 0.874}

Source code in src/ragas/evaluation.py

@track_was_completed
def evaluate(
    dataset: t.Union[Dataset, EvaluationDataset],
    metrics: list[Metric] | None = None,
    llm: t.Optional[BaseRagasLLM | LangchainLLM] = None,
    embeddings: t.Optional[BaseRagasEmbeddings | LangchainEmbeddings] = None,
    callbacks: Callbacks = None,
    in_ci: bool = False,
    run_config: RunConfig = RunConfig(),
    token_usage_parser: t.Optional[TokenUsageParser] = None,
    raise_exceptions: bool = False,
    column_map: t.Optional[t.Dict[str, str]] = None,
    show_progress: bool = True,
) -> Result:
    """
    Run the evaluation on the dataset with different metrics

    Parameters
    ----------
    dataset : Dataset[question: list[str], contexts: list[list[str]], answer: list[str], ground_truth: list[list[str]]]
        The dataset in the format of ragas which the metrics will use to score the RAG
        pipeline with
    metrics : list[Metric] , optional
        List of metrics to use for evaluation. If not provided then ragas will run the
        evaluation on the best set of metrics to give a complete view.
    llm: BaseRagasLLM, optional
        The language model to use for the metrics. If not provided then ragas will use
        the default language model for metrics which require an LLM. This can we overridden by the llm specified in
        the metric level with `metric.llm`.
    embeddings: BaseRagasEmbeddings, optional
        The embeddings to use for the metrics. If not provided then ragas will use
        the default embeddings for metrics which require embeddings. This can we overridden by the embeddings specified in
        the metric level with `metric.embeddings`.
    callbacks: Callbacks, optional
        Lifecycle Langchain Callbacks to run during evaluation. Check the
        [langchain documentation](https://python.langchain.com/docs/modules/callbacks/)
        for more information.
    in_ci: bool
        Whether the evaluation is running in CI or not. If set to True then some
        metrics will be run to increase the reproducability of the evaluations. This
        will increase the runtime and cost of evaluations. Default is False.
    run_config: RunConfig, optional
        Configuration for runtime settings like timeout and retries. If not provided,
        default values are used.
    token_usage_parser: TokenUsageParser, optional
        Parser to get the token usage from the LLM result. If not provided then the
        the cost and total tokens will not be calculated. Default is None.
    raise_exceptions: False
        Whether to raise exceptions or not. If set to True then the evaluation will
        raise an exception if any of the metrics fail. If set to False then the
        evaluation will return `np.nan` for the row that failed. Default is False.
    column_map : dict[str, str], optional
        The column names of the dataset to use for evaluation. If the column names of
        the dataset are different from the default ones then you can provide the
        mapping as a dictionary here. Example: If the dataset column name is contexts_v1,
        column_map can be given as {"contexts":"contexts_v1"}
    show_progress: bool, optional
        Whether to show the progress bar during evaluation. If set to False, the progress bar will be disabled. Default is True.

    Returns
    -------
    Result
        Result object containing the scores of each metric. You can use this do analysis
        later.

    Raises
    ------
    ValueError
        if validation fails because the columns required for the metrics are missing or
        if the columns are of the wrong format.

    Examples
    --------
    the basic usage is as follows:
    ```
    from ragas import evaluate

    >>> dataset
    Dataset({
        features: ['question', 'ground_truth', 'answer', 'contexts'],
        num_rows: 30
    })

    >>> result = evaluate(dataset)
    >>> print(result)
    {'context_precision': 0.817,
    'faithfulness': 0.892,
    'answer_relevancy': 0.874}
    ```
    """
    column_map = column_map or {}
    callbacks = callbacks or []

    if helicone_config.is_enabled:
        import uuid

        helicone_config.session_name = "ragas-evaluation"
        helicone_config.session_id = str(uuid.uuid4())

    if dataset is None:
        raise ValueError("Provide dataset!")

    # default metrics
    if metrics is None:
        from ragas.metrics import (
            answer_relevancy,
            context_precision,
            context_recall,
            faithfulness,
        )

        metrics = [answer_relevancy, context_precision, faithfulness, context_recall]

    v1_input = False
    if isinstance(dataset, Dataset):
        # remap column names from the dataset
        v1_input = True
        dataset = remap_column_names(dataset, column_map)
        dataset = convert_v1_to_v2_dataset(dataset)
        # validation
        dataset = EvaluationDataset.from_list(dataset.to_list())

    if isinstance(dataset, EvaluationDataset):
        validate_required_columns(dataset, metrics)
        validate_supported_metrics(dataset, metrics)

    # set the llm and embeddings
    if isinstance(llm, LangchainLLM):
        llm = LangchainLLMWrapper(llm, run_config=run_config)
    if isinstance(embeddings, LangchainEmbeddings):
        embeddings = LangchainEmbeddingsWrapper(embeddings)

    # init llms and embeddings
    binary_metrics = []
    llm_changed: t.List[int] = []
    embeddings_changed: t.List[int] = []
    reproducable_metrics: t.List[int] = []
    answer_correctness_is_set = -1

    # loop through the metrics and perform initializations
    for i, metric in enumerate(metrics):
        # set llm and embeddings if not set
        if isinstance(metric, AspectCritic):
            binary_metrics.append(metric.name)
        if isinstance(metric, MetricWithLLM) and metric.llm is None:
            if llm is None:
                llm = llm_factory()
            metric.llm = llm
            llm_changed.append(i)
        if isinstance(metric, MetricWithEmbeddings) and metric.embeddings is None:
            if embeddings is None:
                embeddings = embedding_factory()
            metric.embeddings = embeddings
            embeddings_changed.append(i)
        if isinstance(metric, AnswerCorrectness):
            if metric.answer_similarity is None:
                answer_correctness_is_set = i
        # set reproducibility for metrics if in CI
        if in_ci and is_reproducable(metric):
            if metric.reproducibility == 1:  # type: ignore
                # only set a value if not already set
                metric.reproducibility = 3  # type: ignore
                reproducable_metrics.append(i)

        # init all the models
        metric.init(run_config)

    executor = Executor(
        desc="Evaluating",
        keep_progress_bar=True,
        raise_exceptions=raise_exceptions,
        run_config=run_config,
        show_progress=show_progress,
    )

    # Ragas Callbacks
    # init the callbacks we need for various tasks
    ragas_callbacks: t.Dict[str, BaseCallbackHandler] = {}

    # check if cost needs to be calculated
    if token_usage_parser is not None:
        from ragas.cost import CostCallbackHandler

        cost_cb = CostCallbackHandler(token_usage_parser=token_usage_parser)
        ragas_callbacks["cost_cb"] = cost_cb

    # append all the ragas_callbacks to the callbacks
    for cb in ragas_callbacks.values():
        if isinstance(callbacks, BaseCallbackManager):
            callbacks.add_handler(cb)
        else:
            callbacks.append(cb)

    # new evaluation chain
    row_run_managers = []
    evaluation_rm, evaluation_group_cm = new_group(
        name=RAGAS_EVALUATION_CHAIN_NAME, inputs={}, callbacks=callbacks
    )

    sample_type = dataset.get_sample_type()
    for i, sample in enumerate(dataset):
        row = t.cast(t.Dict[str, t.Any], sample.dict())
        row_rm, row_group_cm = new_group(
            name=f"row {i}",
            inputs=row,
            callbacks=evaluation_group_cm,
        )
        row_run_managers.append((row_rm, row_group_cm))
        if sample_type == SingleTurnSample:
            _ = [
                executor.submit(
                    metric.single_turn_ascore,
                    sample,
                    row_group_cm,
                    name=f"{metric.name}-{i}",
                    timeout=run_config.timeout,
                )
                for metric in metrics
                if isinstance(metric, SingleTurnMetric)
            ]
        elif sample_type == MultiTurnSample:
            _ = [
                executor.submit(
                    metric.multi_turn_ascore,
                    sample,
                    row_group_cm,
                    name=f"{metric.name}-{i}",
                    timeout=run_config.timeout,
                )
                for metric in metrics
                if isinstance(metric, MultiTurnMetric)
            ]
        else:
            raise ValueError(f"Unsupported sample type {sample_type}")

    scores = []
    try:
        # get the results
        results = executor.results()
        if results == []:
            raise ExceptionInRunner()

        # convert results to dataset_like
        for i, _ in enumerate(dataset):
            s = {}
            for j, m in enumerate(metrics):
                s[m.name] = results[len(metrics) * i + j]
            scores.append(s)
            # close the row chain
            row_rm, row_group_cm = row_run_managers[i]
            if not row_group_cm.ended:
                row_rm.on_chain_end(s)

    # run evaluation task
    except Exception as e:
        if not evaluation_group_cm.ended:
            evaluation_rm.on_chain_error(e)

        raise e
    else:
        # evalution run was successful
        # now lets process the results
        # convert to v.1 dataset
        dataset = dataset.to_hf_dataset()
        if v1_input:
            dataset = convert_v2_to_v1_dataset(dataset)

        cost_cb = ragas_callbacks["cost_cb"] if "cost_cb" in ragas_callbacks else None
        result = Result(
            scores=Dataset.from_list(scores),
            dataset=dataset,
            binary_columns=binary_metrics,
            cost_cb=t.cast(
                t.Union["CostCallbackHandler", None],
                cost_cb,
            ),
        )
        if not evaluation_group_cm.ended:
            evaluation_rm.on_chain_end(result)
    finally:
        # reset llms and embeddings if changed
        for i in llm_changed:
            t.cast(MetricWithLLM, metrics[i]).llm = None
        for i in embeddings_changed:
            t.cast(MetricWithEmbeddings, metrics[i]).embeddings = None
        if answer_correctness_is_set != -1:
            t.cast(
                AnswerCorrectness, metrics[answer_correctness_is_set]
            ).answer_similarity = None

        for i in reproducable_metrics:
            metrics[i].reproducibility = 1  # type: ignore

    # log the evaluation event
    metrics_names = [m.name for m in metrics]
    metric_lang = [get_feature_language(m) for m in metrics]
    metric_lang = np.unique([m for m in metric_lang if m is not None])
    track(
        EvaluationEvent(
            event_type="evaluation",
            metrics=metrics_names,
            evaluation_mode="",
            num_rows=len(dataset),
            language=metric_lang[0] if len(metric_lang) > 0 else "",
            in_ci=in_ci,
        )
    )
    return result