class_docstr: Test class for `SignalNoiseRatio` metric.
class_docstr_tok: ["Test","class","for","`","SignalNoiseRatio","`","metric","."]
docstr: Test dtype support of the metric on CPU.
docstr_tok: ["Test","dtype","support","of","the","metric","on","CPU","."]
code: def test_snr_half_cpu(self, preds, target, ref_metric, zero_mean):
      """Test dtype support of the metric on CPU."""
      pytest.xfail("SNR metric does not support cpu + half precision")
  
imports: from functools import partial
  from typing import Callable
  import pytest
  import torch
  from mir_eval.separation import bss_eval_images
  from torch import Tensor
  from torchmetrics.audio import SignalNoiseRatio
  from torchmetrics.functional.audio import signal_noise_ratio
  from unittests import _Input
  from unittests.helpers import seed_all
  from unittests.helpers.testers import MetricTester
label_desc: Use image node_id 4 for calling the TestSNR obj's underlying member method code with example usage: obj.test_snr_half_cpu(preds, target, ref_metric, zero_mean) without return types