docs: def _query_init(k, oracle, query, method='all'):
      """A helper function for query-matching function initialization."""
      if method == 'all':
          a = np.subtract(query, [oracle.f_array[t] for t in oracle.latent[oracle.data[k]]])
          dvec = (a * a).sum(axis=1)  # Could skip the sqrt
          _d = dvec.argmin()
          return oracle.latent[oracle.data[k]][_d], dvec[_d]
  
      else:
          a = np.subtract(query, oracle.f_array[k])
          dvec = (a * a).sum()  # Could skip the sqrt
          return k, dvec