Recall¶

Module Interface¶

class torchmetrics.Recall(num_classes=None, threshold=0.5, average='micro', mdmc_average=None, ignore_index=None, top_k=None, multiclass=None, **kwargs)[source]

Recall.

Note

From v0.10 an 'binary_*', 'multiclass_*', 'multilabel_*' version now exist of each classification metric. Moving forward we recommend using these versions. This base metric will still work as it did prior to v0.10 until v0.11. From v0.11 the task argument introduced in this metric will be required and the general order of arguments may change, such that this metric will just function as an single entrypoint to calling the three specialized versions.

Computes Recall:

$\text{Recall} = \frac{\text{TP}}{\text{TP} + \text{FN}}$

Where $\text{TP}$ and $\text{FN}$ represent the number of true positives and false negatives respecitively. With the use of top_k parameter, this metric can generalize to Recall@K.

The reduction method (how the recall scores are aggregated) is controlled by the average parameter, and additionally by the mdmc_average parameter in the multi-dimensional multi-class case. Accepts all inputs listed in Input types.

Parameters

num_classes¶ (Optional[int]) – Number of classes. Necessary for 'macro', 'weighted' and None average methods.
threshold¶ (float) – Threshold for transforming probability or logit predictions to binary (0,1) predictions, in the case of binary or multi-label inputs. Default value of 0.5 corresponds to input being probabilities.
average¶ (Optional[Literal[‘micro’, ‘macro’, ‘weighted’, ‘none’]]) –
Defines the reduction that is applied. Should be one of the following:
- 'micro' [default]: Calculate the metric globally, across all samples and classes.
- 'macro': Calculate the metric for each class separately, and average the metrics across classes (with equal weights for each class).
- 'weighted': Calculate the metric for each class separately, and average the metrics across classes, weighting each class by its support (tp + fn).
- 'none' or None: Calculate the metric for each class separately, and return the metric for every class.
- 'samples': Calculate the metric for each sample, and average the metrics across samples (with equal weights for each sample).
Note

What is considered a sample in the multi-dimensional multi-class case depends on the value of mdmc_average.
mdmc_average¶ (Optional[str]) –
Defines how averaging is done for multi-dimensional multi-class inputs (on top of the average parameter). Should be one of the following:
- None [default]: Should be left unchanged if your data is not multi-dimensional multi-class.
- 'samplewise': In this case, the statistics are computed separately for each sample on the N axis, and then averaged over samples. The computation for each sample is done by treating the flattened extra axes ... (see Input types) as the N dimension within the sample, and computing the metric for the sample based on that.
- 'global': In this case the N and ... dimensions of the inputs (see Input types) are flattened into a new N_X sample axis, i.e. the inputs are treated as if they were (N_X, C). From here on the average parameter applies as usual.
ignore_index¶ (Optional[int]) – Integer specifying a target class to ignore. If given, this class index does not contribute to the returned score, regardless of reduction method. If an index is ignored, and average=None or 'none', the score for the ignored class will be returned as nan.
top_k¶ (Optional[int]) –
Number of the highest probability or logit score predictions considered finding the correct label, relevant only for (multi-dimensional) multi-class. The default value (None) will be interpreted as 1 for these inputs.

Should be left at default (None) for all other types of inputs.
multiclass¶ (Optional[bool]) – Used only in certain special cases, where you want to treat inputs as a different type than what they appear to be. See the parameter’s documentation section for a more detailed explanation and examples.
kwargs¶ (Any) – Additional keyword arguments, see Advanced metric settings for more info.

Raises

ValueError – If average is none of "micro", "macro", "weighted", "samples", "none", None.

Example

>>> import torch
>>> from torchmetrics import Recall
>>> preds  = torch.tensor([2, 0, 2, 1])
>>> target = torch.tensor([1, 1, 2, 0])
>>> recall = Recall(average='macro', num_classes=3)
>>> recall(preds, target)
tensor(0.3333)
>>> recall = Recall(average='micro')
>>> recall(preds, target)
tensor(0.2500)

Initializes internal Module state, shared by both nn.Module and ScriptModule.

compute()[source]

Computes the recall score based on inputs passed in to update previously.

Returns

If average in ['micro', 'macro', 'weighted', 'samples'], a one-element tensor will be returned
If average in ['none', None], the shape will be (C,), where C stands for the number of classes

Return type

The shape of the returned tensor depends on the average parameter

BinaryRecall¶

class torchmetrics.classification.BinaryRecall(threshold=0.5, multidim_average='global', ignore_index=None, validate_args=True, **kwargs)[source]

Computes Recall for binary tasks:

$\text{Recall} = \frac{\text{TP}}{\text{TP} + \text{FN}}$

Where $\text{TP}$ and $\text{FN}$ represent the number of true positives and false negatives respecitively.

Accepts the following input tensors:

preds (int or float tensor): (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. Addtionally, we convert to int tensor with thresholding using the value in threshold.
target (int tensor): (N, ...)

The influence of the additional dimension ... (if present) will be determined by the multidim_average argument.

Parameters

threshold¶ (float) – Threshold for transforming probability to binary {0,1} predictions
multidim_average¶ (Literal[‘global’, ‘samplewise’]) –
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¶ (Optional[int]) – Specifies a target value that is ignored and does not contribute to the metric calculation
validate_args¶ (bool) – bool indicating if input arguments and tensors should be validated for correctness. Set to False for faster computations.

Returns

If multidim_average is set to global, the metric returns a scalar value. If multidim_average is set to samplewise, the metric returns (N,) vector consisting of a scalar value per sample.

Example (preds is int tensor):

>>> from torchmetrics.classification import BinaryRecall
>>> target = torch.tensor([0, 1, 0, 1, 0, 1])
>>> preds = torch.tensor([0, 0, 1, 1, 0, 1])
>>> metric = BinaryRecall()
>>> metric(preds, target)
tensor(0.6667)

Example (preds is float tensor):

>>> from torchmetrics.classification import BinaryRecall
>>> target = torch.tensor([0, 1, 0, 1, 0, 1])
>>> preds = torch.tensor([0.11, 0.22, 0.84, 0.73, 0.33, 0.92])
>>> metric = BinaryRecall()
>>> metric(preds, target)
tensor(0.6667)

Example (multidim tensors):

>>> from torchmetrics.classification import BinaryRecall
>>> target = torch.tensor([[[0, 1], [1, 0], [0, 1]], [[1, 1], [0, 0], [1, 0]]])
>>> preds = torch.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 = BinaryRecall(multidim_average='samplewise')
>>> metric(preds, target)
tensor([0.6667, 0.0000])

Initializes internal Module state, shared by both nn.Module and ScriptModule.

compute()[source]

Computes the final statistics.

Return type

Tensor

Returns

The metric returns 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)

MulticlassRecall¶

class torchmetrics.classification.MulticlassRecall(num_classes, top_k=1, average='macro', multidim_average='global', ignore_index=None, validate_args=True, **kwargs)[source]

Computes Recall for multiclass tasks:

$\text{Recall} = \frac{\text{TP}}{\text{TP} + \text{FN}}$

Where $\text{TP}$ and $\text{FN}$ represent the number of true positives and false negatives respecitively.

Accepts the following input tensors:

preds: (N, ...) (int tensor) or (N, C, ..) (float tensor). If preds is a floating point we apply torch.argmax along the C dimension to automatically convert probabilities/logits into an int tensor.
target (int tensor): (N, ...)

The influence of the additional dimension ... (if present) will be determined by the multidim_average argument.

Parameters

num_classes¶ (int) – Integer specifing the number of classes
average¶ (Optional[Literal[‘micro’, ‘macro’, ‘weighted’, ‘none’]]) –
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¶ (int) – Number of highest probability or logit score predictions considered to find the correct label. Only works when preds contain probabilities/logits.
multidim_average¶ (Literal[‘global’, ‘samplewise’]) –
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¶ (Optional[int]) – Specifies a target value that is ignored and does not contribute to the metric calculation
validate_args¶ (bool) – bool indicating if input arguments and tensors should be validated for correctness. Set to False for faster computations.

Returns

If multidim_average is set to global:
- If average='micro'/'macro'/'weighted', the output will be a scalar tensor
- If average=None/'none', the shape will be (C,)
If multidim_average is set to samplewise:
- If average='micro'/'macro'/'weighted', the shape will be (N,)
- If average=None/'none', the shape will be (N, C)

Return type

The returned shape depends on the average and multidim_average arguments

Example (preds is int tensor):

>>> from torchmetrics.classification import MulticlassRecall
>>> target = torch.tensor([2, 1, 0, 0])
>>> preds = torch.tensor([2, 1, 0, 1])
>>> metric = MulticlassRecall(num_classes=3)
>>> metric(preds, target)
tensor(0.8333)
>>> metric = MulticlassRecall(num_classes=3, average=None)
>>> metric(preds, target)
tensor([0.5000, 1.0000, 1.0000])

Example (preds is float tensor):

>>> from torchmetrics.classification import MulticlassRecall
>>> target = torch.tensor([2, 1, 0, 0])
>>> preds = torch.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 = MulticlassRecall(num_classes=3)
>>> metric(preds, target)
tensor(0.8333)
>>> metric = MulticlassRecall(num_classes=3, average=None)
>>> metric(preds, target)
tensor([0.5000, 1.0000, 1.0000])

Example (multidim tensors):

>>> from torchmetrics.classification import MulticlassRecall
>>> target = torch.tensor([[[0, 1], [2, 1], [0, 2]], [[1, 1], [2, 0], [1, 2]]])
>>> preds = torch.tensor([[[0, 2], [2, 0], [0, 1]], [[2, 2], [2, 1], [1, 0]]])
>>> metric = MulticlassRecall(num_classes=3, multidim_average='samplewise')
>>> metric(preds, target)
tensor([0.5000, 0.2778])
>>> metric = MulticlassRecall(num_classes=3, multidim_average='samplewise', average=None)
>>> metric(preds, target)
tensor([[1.0000, 0.0000, 0.5000],
        [0.0000, 0.3333, 0.5000]])

Initializes internal Module state, shared by both nn.Module and ScriptModule.

compute()[source]

Computes the final statistics.

Return type

Tensor

Returns

The metric returns 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)

MultilabelRecall¶

class torchmetrics.classification.MultilabelRecall(num_labels, threshold=0.5, average='macro', multidim_average='global', ignore_index=None, validate_args=True, **kwargs)[source]

Computes Recall for multilabel tasks:

$\text{Recall} = \frac{\text{TP}}{\text{TP} + \text{FN}}$

Where $\text{TP}$ and $\text{FN}$ represent the number of true positives and false negatives respecitively.

Accepts the following input tensors:

preds (int or float tensor): (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. Addtionally, we convert to int tensor with thresholding using the value in threshold.
target (int tensor): (N, C, ...)

The influence of the additional dimension ... (if present) will be determined by the multidim_average argument.

Parameters

num_labels¶ (int) – Integer specifing the number of labels
threshold¶ (float) – Threshold for transforming probability to binary (0,1) predictions
average¶ (Optional[Literal[‘micro’, ‘macro’, ‘weighted’, ‘none’]]) –
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¶ (Literal[‘global’, ‘samplewise’]) –
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¶ (Optional[int]) – Specifies a target value that is ignored and does not contribute to the metric calculation
validate_args¶ (bool) – bool indicating if input arguments and tensors should be validated for correctness. Set to False for faster computations.

Returns

If multidim_average is set to global:
- If average='micro'/'macro'/'weighted', the output will be a scalar tensor
- If average=None/'none', the shape will be (C,)
If multidim_average is set to samplewise:
- If average='micro'/'macro'/'weighted', the shape will be (N,)
- If average=None/'none', the shape will be (N, C)

Return type

The returned shape depends on the average and multidim_average arguments

Example (preds is int tensor):

>>> from torchmetrics.classification import MultilabelRecall
>>> target = torch.tensor([[0, 1, 0], [1, 0, 1]])
>>> preds = torch.tensor([[0, 0, 1], [1, 0, 1]])
>>> metric = MultilabelRecall(num_labels=3)
>>> metric(preds, target)
tensor(0.6667)
>>> metric = MultilabelRecall(num_labels=3, average=None)
>>> metric(preds, target)
tensor([1., 0., 1.])

Example (preds is float tensor):

>>> from torchmetrics.classification import MultilabelRecall
>>> target = torch.tensor([[0, 1, 0], [1, 0, 1]])
>>> preds = torch.tensor([[0.11, 0.22, 0.84], [0.73, 0.33, 0.92]])
>>> metric = MultilabelRecall(num_labels=3)
>>> metric(preds, target)
tensor(0.6667)
>>> metric = MultilabelRecall(num_labels=3, average=None)
>>> metric(preds, target)
tensor([1., 0., 1.])

Example (multidim tensors):

>>> from torchmetrics.classification import MultilabelRecall
>>> target = torch.tensor([[[0, 1], [1, 0], [0, 1]], [[1, 1], [0, 0], [1, 0]]])
>>> preds = torch.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 = MultilabelRecall(num_labels=3, multidim_average='samplewise')
>>> metric(preds, target)
tensor([0.6667, 0.0000])
>>> metric = MultilabelRecall(num_labels=3, multidim_average='samplewise', average=None)
>>> metric(preds, target)
tensor([[1., 1., 0.],
        [0., 0., 0.]])

Initializes internal Module state, shared by both nn.Module and ScriptModule.

compute()[source]

Computes the final statistics.

Return type

Tensor

Returns

The metric returns 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)

Functional Interface¶

torchmetrics.functional.recall(preds, target, average='micro', mdmc_average=None, ignore_index=None, num_classes=None, threshold=0.5, top_k=None, multiclass=None, task=None, num_labels=None, multidim_average='global', validate_args=True)[source]

Recall.

Note

From v0.10 an 'binary_*', 'multiclass_*', 'multilabel_*' version now exist of each classification metric. Moving forward we recommend using these versions. This base metric will still work as it did prior to v0.10 until v0.11. From v0.11 the task argument introduced in this metric will be required and the general order of arguments may change, such that this metric will just function as an single entrypoint to calling the three specialized versions.

Computes Recall

$\text{Recall} = \frac{\text{TP}}{\text{TP} + \text{FN}}$

Where $\text{TP}$ and $\text{FN}$ represent the number of true positives and false negatives respecitively. With the use of top_k parameter, this metric can generalize to Recall@K.

The reduction method (how the recall scores are aggregated) is controlled by the average parameter, and additionally by the mdmc_average parameter in the multi-dimensional multi-class case. Accepts all inputs listed in Input types.

Parameters

preds¶ (Tensor) – Predictions from model (probabilities, logits or labels)
target¶ (Tensor) – Ground truth values
average¶ (Optional[Literal[‘micro’, ‘macro’, ‘weighted’, ‘none’]]) –
Defines the reduction that is applied. Should be one of the following:
- 'micro' [default]: Calculate the metric globally, across all samples and classes.
- 'macro': Calculate the metric for each class separately, and average the metrics across classes (with equal weights for each class).
- 'weighted': Calculate the metric for each class separately, and average the metrics across classes, weighting each class by its support (tp + fn).
- 'none' or None: Calculate the metric for each class separately, and return the metric for every class.
- 'samples': Calculate the metric for each sample, and average the metrics across samples (with equal weights for each sample).
Note

What is considered a sample in the multi-dimensional multi-class case depends on the value of mdmc_average.

Note

If 'none' and a given class doesn’t occur in the preds or target, the value for the class will be nan.
mdmc_average¶ (Optional[str]) –
Defines how averaging is done for multi-dimensional multi-class inputs (on top of the average parameter). Should be one of the following:
- None [default]: Should be left unchanged if your data is not multi-dimensional multi-class.
- 'samplewise': In this case, the statistics are computed separately for each sample on the N axis, and then averaged over samples. The computation for each sample is done by treating the flattened extra axes ... (see Input types) as the N dimension within the sample, and computing the metric for the sample based on that.
- 'global': In this case the N and ... dimensions of the inputs (see Input types) are flattened into a new N_X sample axis, i.e. the inputs are treated as if they were (N_X, C). From here on the average parameter applies as usual.
ignore_index¶ (Optional[int]) – Integer specifying a target class to ignore. If given, this class index does not contribute to the returned score, regardless of reduction method. If an index is ignored, and average=None or 'none', the score for the ignored class will be returned as nan.
num_classes¶ (Optional[int]) – Number of classes. Necessary for 'macro', 'weighted' and None average methods.
threshold¶ (float) – Threshold for transforming probability or logit predictions to binary (0,1) predictions, in the case of binary or multi-label inputs. Default value of 0.5 corresponds to input being probabilities.
top_k¶ (Optional[int]) –
Number of the highest probability or logit score predictions considered finding the correct label, relevant only for (multi-dimensional) multi-class inputs. The default value (None) will be interpreted as 1 for these inputs.

Should be left at default (None) for all other types of inputs.
multiclass¶ (Optional[bool]) – Used only in certain special cases, where you want to treat inputs as a different type than what they appear to be. See the parameter’s documentation section for a more detailed explanation and examples.

Return type

Tensor

Returns

The shape of the returned tensor depends on the average parameter

If average in ['micro', 'macro', 'weighted', 'samples'], a one-element tensor will be returned
If average in ['none', None], the shape will be (C,), where C stands for the number of classes

Raises

ValueError – If average is not one of "micro", "macro", "weighted", "samples", "none" or None
ValueError – If mdmc_average is not one of None, "samplewise", "global".
ValueError – If average is set but num_classes is not provided.
ValueError – If num_classes is set and ignore_index is not in the range [0, num_classes).

Example

>>> from torchmetrics.functional import recall
>>> preds  = torch.tensor([2, 0, 2, 1])
>>> target = torch.tensor([1, 1, 2, 0])
>>> recall(preds, target, average='macro', num_classes=3)
tensor(0.3333)
>>> recall(preds, target, average='micro')
tensor(0.2500)

binary_recall¶

torchmetrics.functional.classification.binary_recall(preds, target, threshold=0.5, multidim_average='global', ignore_index=None, validate_args=True)[source]

Computes Recall for binary tasks:

$\text{Recall} = \frac{\text{TP}}{\text{TP} + \text{FN}}$

Where $\text{TP}$ and $\text{FN}$ represent the number of true positives and false negatives respecitively.

Accepts the following input tensors:

preds (int or float tensor): (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. Addtionally, we convert to int tensor with thresholding using the value in threshold.
target (int tensor): (N, ...)

The influence of the additional dimension ... (if present) will be determined by the multidim_average argument.

Parameters

preds¶ (Tensor) – Tensor with predictions
target¶ (Tensor) – Tensor with true labels
threshold¶ (float) – Threshold for transforming probability to binary {0,1} predictions
multidim_average¶ (Literal[‘global’, ‘samplewise’]) –
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¶ (Optional[int]) – Specifies a target value that is ignored and does not contribute to the metric calculation
validate_args¶ (bool) – bool indicating if input arguments and tensors should be validated for correctness. Set to False for faster computations.

Return type

Tensor

Returns

If multidim_average is set to global, the metric returns a scalar value. If multidim_average is set to samplewise, the metric returns (N,) vector consisting of a scalar value per sample.

Example (preds is int tensor):

>>> from torchmetrics.functional.classification import binary_recall
>>> target = torch.tensor([0, 1, 0, 1, 0, 1])
>>> preds = torch.tensor([0, 0, 1, 1, 0, 1])
>>> binary_recall(preds, target)
tensor(0.6667)

Example (preds is float tensor):

>>> from torchmetrics.functional.classification import binary_recall
>>> target = torch.tensor([0, 1, 0, 1, 0, 1])
>>> preds = torch.tensor([0.11, 0.22, 0.84, 0.73, 0.33, 0.92])
>>> binary_recall(preds, target)
tensor(0.6667)

Example (multidim tensors):

>>> from torchmetrics.functional.classification import binary_recall
>>> target = torch.tensor([[[0, 1], [1, 0], [0, 1]], [[1, 1], [0, 0], [1, 0]]])
>>> preds = torch.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]],
...     ]
... )
>>> binary_recall(preds, target, multidim_average='samplewise')
tensor([0.6667, 0.0000])

multiclass_recall¶

torchmetrics.functional.classification.multiclass_recall(preds, target, num_classes, average='macro', top_k=1, multidim_average='global', ignore_index=None, validate_args=True)[source]

Computes Recall for multiclass tasks:

$\text{Recall} = \frac{\text{TP}}{\text{TP} + \text{FN}}$

Where $\text{TP}$ and $\text{FN}$ represent the number of true positives and false negatives respecitively.

Accepts the following input tensors:

preds: (N, ...) (int tensor) or (N, C, ..) (float tensor). If preds is a floating point we apply torch.argmax along the C dimension to automatically convert probabilities/logits into an int tensor.
target (int tensor): (N, ...)

The influence of the additional dimension ... (if present) will be determined by the multidim_average argument.

Parameters

preds¶ (Tensor) – Tensor with predictions
target¶ (Tensor) – Tensor with true labels
num_classes¶ (int) – Integer specifing the number of classes
average¶ (Optional[Literal[‘micro’, ‘macro’, ‘weighted’, ‘none’]]) –
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¶ (int) – Number of highest probability or logit score predictions considered to find the correct label. Only works when preds contain probabilities/logits.
multidim_average¶ (Literal[‘global’, ‘samplewise’]) –
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¶ (Optional[int]) – Specifies a target value that is ignored and does not contribute to the metric calculation
validate_args¶ (bool) – bool indicating if input arguments and tensors should be validated for correctness. Set to False for faster computations.

Returns

If multidim_average is set to global:
- If average='micro'/'macro'/'weighted', the output will be a scalar tensor
- If average=None/'none', the shape will be (C,)
If multidim_average is set to samplewise:
- If average='micro'/'macro'/'weighted', the shape will be (N,)
- If average=None/'none', the shape will be (N, C)

Return type

The returned shape depends on the average and multidim_average arguments

Example (preds is int tensor):

>>> from torchmetrics.functional.classification import multiclass_recall
>>> target = torch.tensor([2, 1, 0, 0])
>>> preds = torch.tensor([2, 1, 0, 1])
>>> multiclass_recall(preds, target, num_classes=3)
tensor(0.8333)
>>> multiclass_recall(preds, target, num_classes=3, average=None)
tensor([0.5000, 1.0000, 1.0000])

Example (preds is float tensor):

>>> from torchmetrics.functional.classification import multiclass_recall
>>> target = torch.tensor([2, 1, 0, 0])
>>> preds = torch.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],
... ])
>>> multiclass_recall(preds, target, num_classes=3)
tensor(0.8333)
>>> multiclass_recall(preds, target, num_classes=3, average=None)
tensor([0.5000, 1.0000, 1.0000])

Example (multidim tensors):

>>> from torchmetrics.functional.classification import multiclass_recall
>>> target = torch.tensor([[[0, 1], [2, 1], [0, 2]], [[1, 1], [2, 0], [1, 2]]])
>>> preds = torch.tensor([[[0, 2], [2, 0], [0, 1]], [[2, 2], [2, 1], [1, 0]]])
>>> multiclass_recall(preds, target, num_classes=3, multidim_average='samplewise')
tensor([0.5000, 0.2778])
>>> multiclass_recall(preds, target, num_classes=3, multidim_average='samplewise', average=None)
tensor([[1.0000, 0.0000, 0.5000],
        [0.0000, 0.3333, 0.5000]])

multilabel_recall¶

torchmetrics.functional.classification.multilabel_recall(preds, target, num_labels, threshold=0.5, average='macro', multidim_average='global', ignore_index=None, validate_args=True)[source]

Computes Recall for multilabel tasks:

$\text{Recall} = \frac{\text{TP}}{\text{TP} + \text{FN}}$

Where $\text{TP}$ and $\text{FN}$ represent the number of true positives and false negatives respecitively.

Accepts the following input tensors:

preds (int or float tensor): (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. Addtionally, we convert to int tensor with thresholding using the value in threshold.
target (int tensor): (N, C, ...)

The influence of the additional dimension ... (if present) will be determined by the multidim_average argument.

Parameters

preds¶ (Tensor) – Tensor with predictions
target¶ (Tensor) – Tensor with true labels
num_labels¶ (int) – Integer specifing the number of labels
threshold¶ (float) – Threshold for transforming probability to binary (0,1) predictions
average¶ (Optional[Literal[‘micro’, ‘macro’, ‘weighted’, ‘none’]]) –
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¶ (Literal[‘global’, ‘samplewise’]) –
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¶ (Optional[int]) – Specifies a target value that is ignored and does not contribute to the metric calculation
validate_args¶ (bool) – bool indicating if input arguments and tensors should be validated for correctness. Set to False for faster computations.

Returns

If multidim_average is set to global:
- If average='micro'/'macro'/'weighted', the output will be a scalar tensor
- If average=None/'none', the shape will be (C,)
If multidim_average is set to samplewise:
- If average='micro'/'macro'/'weighted', the shape will be (N,)
- If average=None/'none', the shape will be (N, C)

Return type

The returned shape depends on the average and multidim_average arguments

Example (preds is int tensor):

>>> from torchmetrics.functional.classification import multilabel_recall
>>> target = torch.tensor([[0, 1, 0], [1, 0, 1]])
>>> preds = torch.tensor([[0, 0, 1], [1, 0, 1]])
>>> multilabel_recall(preds, target, num_labels=3)
tensor(0.6667)
>>> multilabel_recall(preds, target, num_labels=3, average=None)
tensor([1., 0., 1.])

Example (preds is float tensor):

>>> from torchmetrics.functional.classification import multilabel_recall
>>> target = torch.tensor([[0, 1, 0], [1, 0, 1]])
>>> preds = torch.tensor([[0.11, 0.22, 0.84], [0.73, 0.33, 0.92]])
>>> multilabel_recall(preds, target, num_labels=3)
tensor(0.6667)
>>> multilabel_recall(preds, target, num_labels=3, average=None)
tensor([1., 0., 1.])

Example (multidim tensors):

>>> from torchmetrics.functional.classification import multilabel_recall
>>> target = torch.tensor([[[0, 1], [1, 0], [0, 1]], [[1, 1], [0, 0], [1, 0]]])
>>> preds = torch.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]],
...     ]
... )
>>> multilabel_recall(preds, target, num_labels=3, multidim_average='samplewise')
tensor([0.6667, 0.0000])
>>> multilabel_recall(preds, target, num_labels=3, multidim_average='samplewise', average=None)
tensor([[1., 1., 0.],
        [0., 0., 0.]])