updated docs

  This method is described in [1]_.

  Standalone usage:

  Examples

  --------

  >>> import deepchem as dc

  >>> smiles = ['C1C=CC=CC=1']

  >>> featurizer = dc.feat.BPSymmetryFunctionInput(max_atoms=10)

  >>> import deepchem as dc

  >>> from rdkit import Chem

  >>> smiles = ['C1=CC=CC=C1']

  >>> # Example 1: (size = 2048, radius = 4)

  >>> featurizer = dc.feat.CircularFingerprint(size=2048, radius=4)

  >>> features = featurizer.featurize(smiles)

  >>> import deepchem as dc

  >>> featurizer = dc.feat.OneHotFeaturizer()

  >>> smiles = ['CC(=O)OC1=CC=CC=C1C(=O)O']

  >>> smiles = ['CCC']

  >>> encodings = featurizer.featurize(smiles)

  >>> type(encodings[0])

  <class 'numpy.ndarray'>

  >>> encodings[0].shape

  (100, 35)

  >>> featurizer.untransform(encodings[0])

  'CC(=O)Oc1ccccc1C(=O)O'

  'CCC'

  Note

  ----