# Copyright The Lightning team. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. from typing import Any, Callable, List, Optional, Union import torch from torch import Tensor from typing_extensions import Literal from torchmetrics.classification.base import _ClassificationTaskWrapper from torchmetrics.functional.classification.stat_scores import ( _binary_stat_scores_arg_validation, _binary_stat_scores_compute, _binary_stat_scores_format, _binary_stat_scores_tensor_validation, _binary_stat_scores_update, _multiclass_stat_scores_arg_validation, _multiclass_stat_scores_compute, _multiclass_stat_scores_format, _multiclass_stat_scores_tensor_validation, _multiclass_stat_scores_update, _multilabel_stat_scores_arg_validation, _multilabel_stat_scores_compute, _multilabel_stat_scores_format, _multilabel_stat_scores_tensor_validation, _multilabel_stat_scores_update, ) from torchmetrics.metric import Metric from torchmetrics.utilities.data import dim_zero_cat from torchmetrics.utilities.enums import ClassificationTask class _AbstractStatScores(Metric): tp: Union[List[Tensor], Tensor] fp: Union[List[Tensor], Tensor] tn: Union[List[Tensor], Tensor] fn: Union[List[Tensor], Tensor] # define common functions def _create_state( self, size: int, multidim_average: Literal["global", "samplewise"] = "global", ) -> None: """Initialize the states for the different statistics.""" default: Union[Callable[[], list], Callable[[], Tensor]] if multidim_average == "samplewise": default = list dist_reduce_fx = "cat" else: default = lambda: torch.zeros(size, dtype=torch.long) dist_reduce_fx = "sum" self.add_state("tp", default(), dist_reduce_fx=dist_reduce_fx) self.add_state("fp", default(), dist_reduce_fx=dist_reduce_fx) self.add_state("tn", default(), dist_reduce_fx=dist_reduce_fx) self.add_state("fn", default(), dist_reduce_fx=dist_reduce_fx) def _update_state(self, tp: Tensor, fp: Tensor, tn: Tensor, fn: Tensor) -> None: """Update states depending on multidim_average argument.""" if self.multidim_average == "samplewise": self.tp.append(tp) # type: ignore[union-attr] self.fp.append(fp) # type: ignore[union-attr] self.tn.append(tn) # type: ignore[union-attr] self.fn.append(fn) # type: ignore[union-attr] else: self.tp = self.tp + tp if not isinstance(self.tp, list) else [*self.tp, tp] self.fp = self.fp + fp if not isinstance(self.fp, list) else [*self.fp, fp] self.tn = self.tn + tn if not isinstance(self.tn, list) else [*self.tn, tn] self.fn = self.fn + fn if not isinstance(self.fn, list) else [*self.fn, fn] def _final_state(self) -> tuple[Tensor, Tensor, Tensor, Tensor]: """Aggregate states that are lists and return final states.""" tp = dim_zero_cat(self.tp) fp = dim_zero_cat(self.fp) tn = dim_zero_cat(self.tn) fn = dim_zero_cat(self.fn) return tp, fp, tn, fn class BinaryStatScores(_AbstractStatScores): r"""Compute true positives, false positives, true negatives, false negatives and the support for binary tasks. Related to `Type I and Type II errors`_. As input to ``forward`` and ``update`` the metric accepts the following input: - ``preds`` (:class:`~torch.Tensor`): An int or float tensor of shape ``(N, ...)``. If preds is a floating point tensor with values outside [0,1] range we consider the input to be logits and will auto apply sigmoid per element. Additionally, we convert to int tensor with thresholding using the value in ``threshold``. - ``target`` (:class:`~torch.Tensor`): An int tensor of shape ``(N, ...)`` As output to ``forward`` and ``compute`` the metric returns the following output: - ``bss`` (:class:`~torch.Tensor`): A tensor of shape ``(..., 5)``, where the last dimension corresponds to ``[tp, fp, tn, fn, sup]`` (``sup`` stands for support and equals ``tp + fn``). The shape depends on the ``multidim_average`` parameter: - If ``multidim_average`` is set to ``global``, the shape will be ``(5,)`` - If ``multidim_average`` is set to ``samplewise``, the shape will be ``(N, 5)`` If ``multidim_average`` is set to ``samplewise`` we expect at least one additional dimension ``...`` to be present, which the reduction will then be applied over instead of the sample dimension ``N``. Args: threshold: Threshold for transforming probability to binary {0,1} predictions multidim_average: Defines how additionally dimensions ``...`` should be handled. Should be one of the following: - ``global``: Additional dimensions are flatted along the batch dimension - ``samplewise``: Statistic will be calculated independently for each sample on the ``N`` axis. The statistics in this case are calculated over the additional dimensions. ignore_index: Specifies a target value that is ignored and does not contribute to the metric calculation validate_args: bool indicating if input arguments and tensors should be validated for correctness. Set to ``False`` for faster computations. kwargs: Additional keyword arguments, see :ref:`Metric kwargs` for more info. Example (preds is int tensor): >>> from torch import tensor >>> from torchmetrics.classification import BinaryStatScores >>> target = tensor([0, 1, 0, 1, 0, 1]) >>> preds = tensor([0, 0, 1, 1, 0, 1]) >>> metric = BinaryStatScores() >>> metric(preds, target) tensor([2, 1, 2, 1, 3]) Example (preds is float tensor): >>> from torchmetrics.classification import BinaryStatScores >>> target = tensor([0, 1, 0, 1, 0, 1]) >>> preds = tensor([0.11, 0.22, 0.84, 0.73, 0.33, 0.92]) >>> metric = BinaryStatScores() >>> metric(preds, target) tensor([2, 1, 2, 1, 3]) Example (multidim tensors): >>> from torchmetrics.classification import BinaryStatScores >>> target = tensor([[[0, 1], [1, 0], [0, 1]], [[1, 1], [0, 0], [1, 0]]]) >>> preds = tensor([[[0.59, 0.91], [0.91, 0.99], [0.63, 0.04]], ... [[0.38, 0.04], [0.86, 0.780], [0.45, 0.37]]]) >>> metric = BinaryStatScores(multidim_average='samplewise') >>> metric(preds, target) tensor([[2, 3, 0, 1, 3], [0, 2, 1, 3, 3]]) """ is_differentiable: bool = False higher_is_better: Optional[bool] = None full_state_update: bool = False def __init__( self, threshold: float = 0.5, multidim_average: Literal["global", "samplewise"] = "global", ignore_index: Optional[int] = None, validate_args: bool = True, **kwargs: Any, ) -> None: zero_division = kwargs.pop("zero_division", 0) super(_AbstractStatScores, self).__init__(**kwargs) if validate_args: _binary_stat_scores_arg_validation(threshold, multidim_average, ignore_index, zero_division) self.threshold = threshold self.multidim_average = multidim_average self.ignore_index = ignore_index self.validate_args = validate_args self.zero_division = zero_division self._create_state(size=1, multidim_average=multidim_average) def update(self, preds: Tensor, target: Tensor) -> None: """Update state with predictions and targets.""" if self.validate_args: _binary_stat_scores_tensor_validation(preds, target, self.multidim_average, self.ignore_index) preds, target = _binary_stat_scores_format(preds, target, self.threshold, self.ignore_index) tp, fp, tn, fn = _binary_stat_scores_update(preds, target, self.multidim_average) self._update_state(tp, fp, tn, fn) def compute(self) -> Tensor: """Compute the final statistics.""" tp, fp, tn, fn = self._final_state() return _binary_stat_scores_compute(tp, fp, tn, fn, self.multidim_average) class MulticlassStatScores(_AbstractStatScores): r"""Computes true positives, false positives, true negatives, false negatives and the support for multiclass tasks. Related to `Type I and Type II errors`_. As input to ``forward`` and ``update`` the metric accepts the following input: - ``preds`` (:class:`~torch.Tensor`): An int tensor of shape ``(N, ...)`` or float tensor of shape ``(N, C, ..)``. If preds is a floating point we apply ``torch.argmax`` along the ``C`` dimension to automatically convert probabilities/logits into an int tensor. - ``target`` (:class:`~torch.Tensor`): An int tensor of shape ``(N, ...)`` As output to ``forward`` and ``compute`` the metric returns the following output: - ``mcss`` (:class:`~torch.Tensor`): A tensor of shape ``(..., 5)``, where the last dimension corresponds to ``[tp, fp, tn, fn, sup]`` (``sup`` stands for support and equals ``tp + fn``). The shape depends on ``average`` and ``multidim_average`` parameters: - If ``multidim_average`` is set to ``global``: - If ``average='micro'/'macro'/'weighted'``, the shape will be ``(5,)`` - If ``average=None/'none'``, the shape will be ``(C, 5)`` - If ``multidim_average`` is set to ``samplewise``: - If ``average='micro'/'macro'/'weighted'``, the shape will be ``(N, 5)`` - If ``average=None/'none'``, the shape will be ``(N, C, 5)`` If ``multidim_average`` is set to ``samplewise`` we expect at least one additional dimension ``...`` to be present, which the reduction will then be applied over instead of the sample dimension ``N``. Args: num_classes: Integer specifying the number of classes average: Defines the reduction that is applied over labels. Should be one of the following: - ``micro``: Sum statistics over all labels - ``macro``: Calculate statistics for each label and average them - ``weighted``: calculates statistics for each label and computes weighted average using their support - ``"none"`` or ``None``: calculates statistic for each label and applies no reduction top_k: Number of highest probability or logit score predictions considered to find the correct label. Only works when ``preds`` contain probabilities/logits. multidim_average: Defines how additionally dimensions ``...`` should be handled. Should be one of the following: - ``global``: Additional dimensions are flatted along the batch dimension - ``samplewise``: Statistic will be calculated independently for each sample on the ``N`` axis. The statistics in this case are calculated over the additional dimensions. ignore_index: Specifies a target value that is ignored and does not contribute to the metric calculation validate_args: bool indicating if input arguments and tensors should be validated for correctness. Set to ``False`` for faster computations. kwargs: Additional keyword arguments, see :ref:`Metric kwargs` for more info. Example (preds is int tensor): >>> from torch import tensor >>> from torchmetrics.classification import MulticlassStatScores >>> target = tensor([2, 1, 0, 0]) >>> preds = tensor([2, 1, 0, 1]) >>> metric = MulticlassStatScores(num_classes=3, average='micro') >>> metric(preds, target) tensor([3, 1, 7, 1, 4]) >>> mcss = MulticlassStatScores(num_classes=3, average=None) >>> mcss(preds, target) tensor([[1, 0, 2, 1, 2], [1, 1, 2, 0, 1], [1, 0, 3, 0, 1]]) Example (preds is float tensor): >>> from torchmetrics.classification import MulticlassStatScores >>> target = tensor([2, 1, 0, 0]) >>> preds = tensor([[0.16, 0.26, 0.58], ... [0.22, 0.61, 0.17], ... [0.71, 0.09, 0.20], ... [0.05, 0.82, 0.13]]) >>> metric = MulticlassStatScores(num_classes=3, average='micro') >>> metric(preds, target) tensor([3, 1, 7, 1, 4]) >>> mcss = MulticlassStatScores(num_classes=3, average=None) >>> mcss(preds, target) tensor([[1, 0, 2, 1, 2], [1, 1, 2, 0, 1], [1, 0, 3, 0, 1]]) Example (multidim tensors): >>> from torchmetrics.classification import MulticlassStatScores >>> target = tensor([[[0, 1], [2, 1], [0, 2]], [[1, 1], [2, 0], [1, 2]]]) >>> preds = tensor([[[0, 2], [2, 0], [0, 1]], [[2, 2], [2, 1], [1, 0]]]) >>> metric = MulticlassStatScores(num_classes=3, multidim_average="samplewise", average='micro') >>> metric(preds, target) tensor([[3, 3, 9, 3, 6], [2, 4, 8, 4, 6]]) >>> mcss = MulticlassStatScores(num_classes=3, multidim_average="samplewise", average=None) >>> mcss(preds, target) tensor([[[2, 1, 3, 0, 2], [0, 1, 3, 2, 2], [1, 1, 3, 1, 2]], [[0, 1, 4, 1, 1], [1, 1, 2, 2, 3], [1, 2, 2, 1, 2]]]) """ is_differentiable: bool = False higher_is_better: Optional[bool] = None full_state_update: bool = False def __init__( self, num_classes: Optional[int] = None, top_k: int = 1, average: Optional[Literal["micro", "macro", "weighted", "none"]] = "macro", multidim_average: Literal["global", "samplewise"] = "global", ignore_index: Optional[int] = None, validate_args: bool = True, **kwargs: Any, ) -> None: zero_division = kwargs.pop("zero_division", 0) super(_AbstractStatScores, self).__init__(**kwargs) if validate_args: _multiclass_stat_scores_arg_validation( num_classes, top_k, average, multidim_average, ignore_index, zero_division ) self.num_classes = num_classes self.top_k = top_k self.average = average self.multidim_average = multidim_average self.ignore_index = ignore_index self.validate_args = validate_args self.zero_division = zero_division self._create_state( size=1 if (average == "micro" and top_k == 1) else (num_classes or 1), multidim_average=multidim_average ) def update(self, preds: Tensor, target: Tensor) -> None: """Update state with predictions and targets.""" if self.validate_args: _multiclass_stat_scores_tensor_validation( preds, target, self.num_classes, self.multidim_average, self.ignore_index ) preds, target = _multiclass_stat_scores_format(preds, target, self.top_k) num_classes = self.num_classes if self.num_classes is not None else 1 tp, fp, tn, fn = _multiclass_stat_scores_update( preds, target, num_classes, self.top_k, self.average, self.multidim_average, self.ignore_index ) self._update_state(tp, fp, tn, fn) def compute(self) -> Tensor: """Compute the final statistics.""" tp, fp, tn, fn = self._final_state() return _multiclass_stat_scores_compute(tp, fp, tn, fn, self.average, self.multidim_average) class MultilabelStatScores(_AbstractStatScores): r"""Compute true positives, false positives, true negatives, false negatives and the support for multilabel tasks. Related to `Type I and Type II errors`_. As input to ``forward`` and ``update`` the metric accepts the following input: - ``preds`` (:class:`~torch.Tensor`): An int or float tensor of shape ``(N, C, ...)``. If preds is a floating point tensor with values outside [0,1] range we consider the input to be logits and will auto apply sigmoid per element. Additionally, we convert to int tensor with thresholding using the value in ``threshold``. - ``target`` (:class:`~torch.Tensor`): An int tensor of shape ``(N, C, ...)`` As output to ``forward`` and ``compute`` the metric returns the following output: - ``mlss`` (:class:`~torch.Tensor`): A tensor of shape ``(..., 5)``, where the last dimension corresponds to ``[tp, fp, tn, fn, sup]`` (``sup`` stands for support and equals ``tp + fn``). The shape depends on ``average`` and ``multidim_average`` parameters: - If ``multidim_average`` is set to ``global``: - If ``average='micro'/'macro'/'weighted'``, the shape will be ``(5,)`` - If ``average=None/'none'``, the shape will be ``(C, 5)`` - If ``multidim_average`` is set to ``samplewise``: - If ``average='micro'/'macro'/'weighted'``, the shape will be ``(N, 5)`` - If ``average=None/'none'``, the shape will be ``(N, C, 5)`` If ``multidim_average`` is set to ``samplewise`` we expect at least one additional dimension ``...`` to be present, which the reduction will then be applied over instead of the sample dimension ``N``. Args: num_labels: Integer specifying the number of labels threshold: Threshold for transforming probability to binary (0,1) predictions average: Defines the reduction that is applied over labels. Should be one of the following: - ``micro``: Sum statistics over all labels - ``macro``: Calculate statistics for each label and average them - ``weighted``: calculates statistics for each label and computes weighted average using their support - ``"none"`` or ``None``: calculates statistic for each label and applies no reduction multidim_average: Defines how additionally dimensions ``...`` should be handled. Should be one of the following: - ``global``: Additional dimensions are flatted along the batch dimension - ``samplewise``: Statistic will be calculated independently for each sample on the ``N`` axis. The statistics in this case are calculated over the additional dimensions. ignore_index: Specifies a target value that is ignored and does not contribute to the metric calculation validate_args: bool indicating if input arguments and tensors should be validated for correctness. Set to ``False`` for faster computations. kwargs: Additional keyword arguments, see :ref:`Metric kwargs` for more info. Example (preds is int tensor): >>> from torch import tensor >>> from torchmetrics.classification import MultilabelStatScores >>> target = tensor([[0, 1, 0], [1, 0, 1]]) >>> preds = tensor([[0, 0, 1], [1, 0, 1]]) >>> metric = MultilabelStatScores(num_labels=3, average='micro') >>> metric(preds, target) tensor([2, 1, 2, 1, 3]) >>> mlss = MultilabelStatScores(num_labels=3, average=None) >>> mlss(preds, target) tensor([[1, 0, 1, 0, 1], [0, 0, 1, 1, 1], [1, 1, 0, 0, 1]]) Example (preds is float tensor): >>> from torchmetrics.classification import MultilabelStatScores >>> target = tensor([[0, 1, 0], [1, 0, 1]]) >>> preds = tensor([[0.11, 0.22, 0.84], [0.73, 0.33, 0.92]]) >>> metric = MultilabelStatScores(num_labels=3, average='micro') >>> metric(preds, target) tensor([2, 1, 2, 1, 3]) >>> mlss = MultilabelStatScores(num_labels=3, average=None) >>> mlss(preds, target) tensor([[1, 0, 1, 0, 1], [0, 0, 1, 1, 1], [1, 1, 0, 0, 1]]) Example (multidim tensors): >>> from torchmetrics.classification import MultilabelStatScores >>> target = tensor([[[0, 1], [1, 0], [0, 1]], [[1, 1], [0, 0], [1, 0]]]) >>> preds = tensor([[[0.59, 0.91], [0.91, 0.99], [0.63, 0.04]], ... [[0.38, 0.04], [0.86, 0.780], [0.45, 0.37]]]) >>> metric = MultilabelStatScores(num_labels=3, multidim_average='samplewise', average='micro') >>> metric(preds, target) tensor([[2, 3, 0, 1, 3], [0, 2, 1, 3, 3]]) >>> mlss = MultilabelStatScores(num_labels=3, multidim_average='samplewise', average=None) >>> mlss(preds, target) tensor([[[1, 1, 0, 0, 1], [1, 1, 0, 0, 1], [0, 1, 0, 1, 1]], [[0, 0, 0, 2, 2], [0, 2, 0, 0, 0], [0, 0, 1, 1, 1]]]) """ is_differentiable: bool = False higher_is_better: Optional[bool] = None full_state_update: bool = False def __init__( self, num_labels: int, threshold: float = 0.5, average: Optional[Literal["micro", "macro", "weighted", "none"]] = "macro", multidim_average: Literal["global", "samplewise"] = "global", ignore_index: Optional[int] = None, validate_args: bool = True, **kwargs: Any, ) -> None: zero_division = kwargs.pop("zero_division", 0) super(_AbstractStatScores, self).__init__(**kwargs) if validate_args: _multilabel_stat_scores_arg_validation( num_labels, threshold, average, multidim_average, ignore_index, zero_division ) self.num_labels = num_labels self.threshold = threshold self.average = average self.multidim_average = multidim_average self.ignore_index = ignore_index self.validate_args = validate_args self.zero_division = zero_division self._create_state(size=num_labels, multidim_average=multidim_average) def update(self, preds: Tensor, target: Tensor) -> None: """Update state with predictions and targets.""" if self.validate_args: _multilabel_stat_scores_tensor_validation( preds, target, self.num_labels, self.multidim_average, self.ignore_index ) preds, target = _multilabel_stat_scores_format( preds, target, self.num_labels, self.threshold, self.ignore_index ) tp, fp, tn, fn = _multilabel_stat_scores_update(preds, target, self.multidim_average) self._update_state(tp, fp, tn, fn) def compute(self) -> Tensor: """Compute the final statistics.""" tp, fp, tn, fn = self._final_state() return _multilabel_stat_scores_compute(tp, fp, tn, fn, self.average, self.multidim_average) class StatScores(_ClassificationTaskWrapper): r"""Compute the number of true positives, false positives, true negatives, false negatives and the support. This function is a simple wrapper to get the task specific versions of this metric, which is done by setting the ``task`` argument to either ``'binary'``, ``'multiclass'`` or ``'multilabel'``. See the documentation of :class:`~torchmetrics.classification.BinaryStatScores`, :class:`~torchmetrics.classification.MulticlassStatScores` and :class:`~torchmetrics.classification.MultilabelStatScores` for the specific details of each argument influence and examples. Legacy Example: >>> from torch import tensor >>> preds = tensor([1, 0, 2, 1]) >>> target = tensor([1, 1, 2, 0]) >>> stat_scores = StatScores(task="multiclass", num_classes=3, average='micro') >>> stat_scores(preds, target) tensor([2, 2, 6, 2, 4]) >>> stat_scores = StatScores(task="multiclass", num_classes=3, average=None) >>> stat_scores(preds, target) tensor([[0, 1, 2, 1, 1], [1, 1, 1, 1, 2], [1, 0, 3, 0, 1]]) """ def __new__( # type: ignore[misc] cls: type["StatScores"], task: Literal["binary", "multiclass", "multilabel"], threshold: float = 0.5, num_classes: Optional[int] = None, num_labels: Optional[int] = None, average: Optional[Literal["micro", "macro", "weighted", "none"]] = "micro", multidim_average: Optional[Literal["global", "samplewise"]] = "global", top_k: Optional[int] = 1, ignore_index: Optional[int] = None, validate_args: bool = True, **kwargs: Any, ) -> Metric: """Initialize task metric.""" task = ClassificationTask.from_str(task) assert multidim_average is not None # noqa: S101 # needed for mypy kwargs.update({ "multidim_average": multidim_average, "ignore_index": ignore_index, "validate_args": validate_args, }) if task == ClassificationTask.BINARY: return BinaryStatScores(threshold, **kwargs) if task == ClassificationTask.MULTICLASS: if not isinstance(num_classes, int): raise ValueError(f"`num_classes` is expected to be `int` but `{type(num_classes)} was passed.`") if not isinstance(top_k, int): raise ValueError(f"`top_k` is expected to be `int` but `{type(top_k)} was passed.`") return MulticlassStatScores(num_classes, top_k, average, **kwargs) if task == ClassificationTask.MULTILABEL: if not isinstance(num_labels, int): raise ValueError(f"`num_labels` is expected to be `int` but `{type(num_labels)} was passed.`") return MultilabelStatScores(num_labels, threshold, average, **kwargs) raise ValueError(f"Task {task} not supported!")