Mean

Module Interface

class torchmetrics.MeanMetric(nan_strategy='warn', **kwargs)

Aggregate a stream of value into their mean value.

As input to forward and update the metric accepts the following input

• value (float or Tensor): a single float or an tensor of float values with arbitary shape (...,).

• weight (float or Tensor): a single float or an tensor of float value with arbitary shape (...,). Needs to be broadcastable with the shape of value tensor.

As output of forward and compute the metric returns the following output

• agg (Tensor): scalar float tensor with aggregated (weighted) mean over all inputs received

Parameters

nan_strategy (Union[str, float]) –

options:

• 'error': if any nan values are encounted will give a RuntimeError

• 'warn': if any nan values are encounted will give a warning and continue

• 'ignore': all nan values are silently removed

• a float: if a float is provided will impude any nan values with this value

kwargs: Additional keyword arguments, see Advanced metric settings for more info.

Raises

ValueError – If nan_strategy is not one of error, warn, ignore or a float

Example

>>> from torchmetrics.aggregation import MeanMetric
>>> metric = MeanMetric()
>>> metric.update(1)
>>> metric.update(torch.tensor([2, 3]))
>>> metric.compute()
tensor(2.)

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

plot(val=None, ax=None)

Plot a single or multiple values from the metric.

Parameters

• val (Union[Tensor, Sequence[Tensor], None]) – Either a single result from calling metric.forward or metric.compute or a list of these results. If no value is provided, will automatically call metric.compute and plot that result.

• ax (Optional[Axes]) – An matplotlib axis object. If provided will add plot to that axis

Return type

Tuple[Figure, Union[Axes, ndarray]]

Returns

Figure and Axes object

Raises

ModuleNotFoundError – If matplotlib is not installed

>>> # Example plotting a single value
>>> from torchmetrics.aggregation import MeanMetric
>>> metric = MeanMetric()
>>> metric.update([1, 2, 3])
>>> fig_, ax_ = metric.plot()

(Source code, png, hires.png, pdf)

>>> # Example plotting multiple values
>>> from torchmetrics.aggregation import MeanMetric
>>> metric = MeanMetric()
>>> values = [ ]
>>> for i in range(10):
...     values.append(metric([i, i+1]))
>>> fig_, ax_ = metric.plot(values)

(Source code, png, hires.png, pdf)