class_docstr: Dictionary-like object representing an SALib Problem specification.
  
  Attributes
  ----------
  samples : np.array, of generated samples
  results : np.array, of evaluations (i.e., model outputs)
  analysis : np.array or dict, of sensitivity indices
docstr: Convert results to Pandas DataFrame.
docstr_tok: ["Convert","results","to","Pandas","DataFrame","."]
code: def to_df(self):
      """Convert results to Pandas DataFrame."""
      an_res = self._analysis
      if isinstance(an_res, ResultDict):
          return an_res.to_df()
      elif isinstance(an_res, dict):
          # case where analysis result is a dict of ResultDicts
          return [an.to_df() for an in list(an_res.values())]
  
      raise RuntimeError("Analysis not yet conducted")
  
imports: import warnings
  import importlib
  from types import MethodType
  from functools import partial, wraps
  from multiprocess import Pool, cpu_count
  import numpy
  import SALib.sample
  import SALib.analyze
  from SALib.util import avail_approaches
  from SALib.util.results import ResultDict
label_desc: Use image node_id 15 for calling the ProblemSpec obj's underlying member method code with example usage: obj.to_df() and returns: an_res, unknown