torch.nn.utils.clip_grad_norm_(parameters, max_norm, norm_type=2.0, error_if_nonfinite=False)[source]

Clips gradient norm of an iterable of parameters.

The norm is computed over all gradients together, as if they were concatenated into a single vector. Gradients are modified in-place.

Parameters
• parameters (Iterable[Tensor] or Tensor) – an iterable of Tensors or a single Tensor that will have gradients normalized

• max_norm (float or int) – max norm of the gradients

• norm_type (float or int) – type of the used p-norm. Can be 'inf' for infinity norm.

• error_if_nonfinite (bool) – if True, an error is thrown if the total norm of the gradients from :attr:parameters is nan, inf, or -inf. Default: False (will switch to True in the future)

Returns

Total norm of the parameters (viewed as a single vector).