docstr: Parameters
  ----------
  ngram str or unicode, string to search for
  
  Returns
  -------
  np.array, list of matching document indices
docstr_tok: ["Parameters","--","--","--","--","--","ngram","str","or","unicode",",","string","to","search","for","Returns","--","--","--","-","np.array",",","list","of","matching","document","indices"]
code: def search_index(self, term: str, non_text: bool = False):
      """
      Parameters
      ----------
      ngram str or unicode, string to search for
  
      Returns
      -------
      np.array, list of matching document indices
      """
      return nonzero(self._document_index_mask(term, non_text))[0]
  
file_path: scattertext/scattertext/Corpus.py
imports: import numpy
  import pandas
  from numpy import nonzero
  from scattertext.TermDocMatrix import TermDocMatrix
label_desc: Use image node_id 5 for calling the Corpus obj's underlying member method code with example usage: obj.search_index(term, non_text) and returns: nonzero