torcheval.metrics.BinaryPrecision

class torcheval.metrics.BinaryPrecision(*, threshold: float = 0.5, device: Optional[device] = None)

Compute the precision score for binary classification tasks, which is calculated as the ratio of the true positives and the sum of true positives and false positives. Its functional version is torcheval.metrics.functional.binary_precision(). We cast NaNs to 0 when classes have zero positive instances in prediction labels (when TP + FP = 0). See also MulticlassPrecision

Parameters:threshold (float, default = 0.5) – Threshold for converting input into predicted labels for each sample. torch.where(input < threshold, 0, 1) will be applied to the input.

Examples:

>>> import torch
>>> from torcheval.metrics import BinaryPrecision
>>> metric = BinaryPrecision()
>>> input = torch.tensor([0, 1, 0, 1])
>>> target = torch.tensor([1, 0, 1, 1])
>>> metric.update(input, target)
>>> metric.compute()
tensor(0.5)  # 1 / 2

>>> metric = BinaryPrecision(threshold=0.7)
>>> input = torch.tensor([0, 0.9, 0.6, 0.7])
>>> target = torch.tensor([1, 0, 1, 1])
>>> metric.update(input, target)
>>> metric.compute()
tensor(0.5)  # 1 / 2

__init__(*, threshold: float = 0.5, device: Optional[device] = None) → None

Initialize a metric object and its internal states.

Use self._add_state() to initialize state variables of your metric class. The state variables should be either torch.Tensor, a list of torch.Tensor, or a dictionary with torch.Tensor as values

Methods

__init__(*[, threshold, device])	Initialize a metric object and its internal states.
compute()	Return the precision score.
load_state_dict(state_dict[, strict])	Loads metric state variables from state_dict.
merge_state(metrics)	Implement this method to update the current metric's state variables to be the merged states of the current metric and input metrics.
reset()	Reset the metric state variables to their default value.
state_dict()	Save metric state variables in state_dict.
to(device, *args, **kwargs)	Move tensors in metric state variables to device.
update(input, target)	Update states with the ground truth labels and predictions.

Attributes

device

The last input device of Metric.to().