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Source code for catalyst.metrics._additive

from typing import Any, Callable, Tuple, Union
import functools

import numpy as np

import torch

from catalyst.metrics._metric import IMetric


def _to_numpy_wrapper(metric_fn: Callable) -> Callable:
    @functools.wraps(metric_fn)
    def _wrapper(
        value: torch.Tensor, *args: Any, **kwargs: Any
    ) -> Union[float, np.ndarray]:
        np_tensor = value.cpu().detach().numpy()
        value = metric_fn(np_tensor, *args, **kwargs)

        return value

    return _wrapper


[docs]class AdditiveMetric(IMetric): """This metric computes mean and std values of input data. Args: compute_on_call: if True, computes and returns metric value during metric call mode: expected dtype returned by the metric, ``"numpy"`` or ``"torch"`` Raises: ValueError: if mode is not supported Examples: .. code-block:: python import numpy as np from catalyst import metrics values = [1, 2, 3, 4, 5] num_samples_list = [1, 2, 3, 4, 5] true_values = [1, 1.666667, 2.333333, 3, 3.666667] metric = metrics.AdditiveMetric() for value, num_samples, true_value in zip(values, num_samples_list, true_values): metric.update(value=value, num_samples=num_samples) mean, _ = metric.compute() assert np.isclose(mean, true_value) .. code-block:: python import os from torch import nn, optim from torch.nn import functional as F from torch.utils.data import DataLoader from catalyst import dl, metrics from catalyst.data import ToTensor from catalyst.contrib.datasets import MNIST model = nn.Sequential(nn.Flatten(), nn.Linear(28 * 28, 10)) optimizer = optim.Adam(model.parameters(), lr=0.02) loaders = { "train": DataLoader( MNIST(os.getcwd(), train=True, download=True, transform=ToTensor()), batch_size=32 ), "valid": DataLoader( MNIST(os.getcwd(), train=False), batch_size=32 ), } class CustomRunner(dl.Runner): def predict_batch(self, batch): # model inference step return self.model(batch[0].to(self.device)) def on_loader_start(self, runner): super().on_loader_start(runner) self.meters = { key: metrics.AdditiveMetric(compute_on_call=False) for key in ["loss", "accuracy01", "accuracy03"] } def handle_batch(self, batch): # model train/valid step # unpack the batch x, y = batch # run model forward pass logits = self.model(x) # compute the loss loss = F.cross_entropy(logits, y) # compute other metrics of interest accuracy01, accuracy03 = metrics.accuracy(logits, y, topk=(1, 3)) # log metrics self.batch_metrics.update( {"loss": loss, "accuracy01": accuracy01, "accuracy03": accuracy03} ) for key in ["loss", "accuracy01", "accuracy03"]: self.meters[key].update( self.batch_metrics[key].item(), self.batch_size ) # run model backward pass if self.is_train_loader: self.engine.backward(loss) self.optimizer.step() self.optimizer.zero_grad() def on_loader_end(self, runner): for key in ["loss", "accuracy01", "accuracy03"]: self.loader_metrics[key] = self.meters[key].compute()[0] super().on_loader_end(runner) runner = CustomRunner() # model training runner.train( model=model, optimizer=optimizer, loaders=loaders, logdir="./logs", num_epochs=5, verbose=True, valid_loader="valid", valid_metric="loss", minimize_valid_metric=True, ) .. note:: Please follow the `minimal examples`_ sections for more use cases. .. _`minimal examples`: https://github.com/catalyst-team/catalyst#minimal-examples # noqa: E501, W505 """ def __init__(self, compute_on_call: bool = True, mode: str = "numpy"): """Init AdditiveMetric""" super().__init__(compute_on_call=compute_on_call) self.n = 0 self.value = 0.0 self.mean = np.nan self.mean_old = 0.0 self.m_s = 0.0 self.std = np.nan self.num_samples = 0 valid_modes = {"numpy", "torch"} if mode not in valid_modes: raise ValueError(f"mode must be one of {valid_modes}, but got mode={mode}") elif mode == "torch": self.update = _to_numpy_wrapper(self.update)
[docs] def reset(self) -> None: """Reset all fields""" self.n = 0 self.value = 0.0 self.mean = np.nan self.mean_old = 0.0 self.m_s = 0.0 self.std = np.nan self.num_samples = 0
[docs] def update(self, value: float, num_samples: int) -> float: """Update mean metric value and std with new value. Args: value: value to update mean and std with num_samples: number of value samples that metrics should be updated with Returns: last value """ self.value = value self.n += 1 self.num_samples += num_samples if self.n == 1: # Force a copy in torch/numpy self.mean = 0.0 + value self.std = 0.0 self.mean_old = self.mean self.m_s = 0.0 else: self.mean = self.mean_old + (value - self.mean_old) * num_samples / float( self.num_samples ) self.m_s += (value - self.mean_old) * (value - self.mean) * num_samples self.mean_old = self.mean self.std = np.sqrt(self.m_s / (self.num_samples - 1.0)) return value
[docs] def compute(self) -> Tuple[float, float]: """ Returns mean and std values of all the input data Returns: tuple of mean and std values """ return self.mean, self.std
AdditiveValueMetric = AdditiveMetric __all__ = ["AdditiveMetric", "AdditiveValueMetric"]