Repository: scikit-learn/scikit-learn
File: sklearn/metrics/_base.py (Python)

Code before:

    y_type = type_of_target(y_true)
    if y_type not in ("binary", "multilabel-indicator"):
        raise ValueError("{0} format is not supported".format(y_type))

    if y_type == "binary":
        return binary_metric(y_true, y_score, sample_weight=sample_weight)

    check_consistent_length(y_true, y_score, sample_weight)
    y_true = check_array(y_true)
    y_score = check_array(y_score)

    not_average_axis = 1
    score_weight = sample_weight
    average_weight = None

    if average == "micro":
        if score_weight is not None:
            score_weight = xp.repeat(score_weight, y_true.shape[1])
        y_true = _ravel(y_true)
        y_score = _ravel(y_score)

    elif average == "weighted":
        if score_weight is not None:
            # in array_api_strict, int64 and float64 cannot be promoted together:
            y_true = xp.astype(xp.asarray(y_true), score_weight.dtype, copy=False)
            average_weight = xp.sum(
                xp.multiply(y_true, xp.reshape(score_weight, (-1, 1))), axis=0
            )
        else:
            average_weight = xp.sum(y_true, axis=0)
        if xpx.isclose(
            xp.sum(average_weight),
            xp.asarray(0, dtype=average_weight.dtype, device=_device),
        ):
            return 0

    elif average == "samples":
        # swap average_weight <-> score_weight
        average_weight = score_weight
        score_weight = None
        not_average_axis = 0

    if y_true.ndim == 1:
        y_true = xp.reshape(y_true, (-1, 1))

    if y_score.ndim == 1:
        y_score = xp.reshape(y_score, (-1, 1))

    n_classes = y_score.shape[not_average_axis]
    score = xp.zeros((n_classes,), device=_device)

Review comment (suggestion):
why not
```suggestion
            y_true = xp.asarray(y_true, dtype=score_weight.dtype)
```

Code after:

    y_type = type_of_target(y_true)
    if y_type not in ("binary", "multilabel-indicator"):
        raise ValueError("{0} format is not supported".format(y_type))

    if y_type == "binary":
        return binary_metric(y_true, y_score, sample_weight=sample_weight)

    check_consistent_length(y_true, y_score, sample_weight)
    y_true = check_array(y_true)
    y_score = check_array(y_score)

    not_average_axis = 1
    score_weight = sample_weight
    average_weight = None

    if average == "micro":
        if score_weight is not None:
            score_weight = xp.repeat(score_weight, y_true.shape[1])
        y_true = _ravel(y_true)
        y_score = _ravel(y_score)

    elif average == "weighted":
        if score_weight is not None:
            #  Mixed integer and float type promotion not defined in array standard
            y_true = xp.asarray(y_true, dtype=score_weight.dtype)
            average_weight = xp.sum(
                xp.multiply(y_true, xp.reshape(score_weight, (-1, 1))), axis=0
            )
        else:
            average_weight = xp.sum(y_true, axis=0)
        if xpx.isclose(
            xp.sum(average_weight),
            xp.asarray(0, dtype=average_weight.dtype, device=_device),
        ):
            return 0

    elif average == "samples":
        # swap average_weight <-> score_weight
        average_weight = score_weight
        score_weight = None
        not_average_axis = 0

    if y_true.ndim == 1:
        y_true = xp.reshape(y_true, (-1, 1))

    if y_score.ndim == 1:
        y_score = xp.reshape(y_score, (-1, 1))

    n_classes = y_score.shape[not_average_axis]
    score = xp.zeros((n_classes,), device=_device)