class_docstr: Mel frequency scale.
class_docstr_tok: ["Mel","frequency","scale","."]
docstr: Convert mel to Hz.
docstr_tok: ["Convert","mel","to","Hz","."]
code: def invert(x):
      """Convert mel to Hz."""
      return 700.0 * (torch.exp(torch.div(x, 1125.0)) - 1.0)
  
imports: import math
  from typing import Union
  import torch
  from typeguard import check_argument_types
label_desc: Use image node_id 2 for calling the MelScale obj's underlying member method code with example usage: obj.invert(x) and returns: unknown