class_docstr: Test PFMFeaturizer.
docstr: Test PFM_to_PPM.
docstr_tok: ["Test","PFM_to_PPM","."]
code: def test_PFM_to_PPM(self):
      """
      Test PFM_to_PPM.
      """
      pfm = self.featurizer.featurize(self.msa)
      ppm = PFM_to_PPM(pfm[0])
      assert ppm.shape == (len(CHARSET) + 1, self.max_length)
      assert ppm[0][0] == 0.5
  
file_path: deepchem/deepchem/feat/tests/test_position_frequency_matrix_featurizer.py
imports: import unittest
  import numpy
  from deepchem.feat.sequence_featurizers.position_frequency_matrix_featurizer import PFMFeaturizer, CHARSET, PFM_to_PPM
label_desc: Use image node_id 3 for calling the TestPFMFeaturizer obj's underlying member method code with example usage: obj.test_PFM_to_PPM() without return types