code: def _init_matrix(self, data, index, columns, dtype=None):
          
          data = prep_ndarray(data, copy=False)
          index, columns = self._prep_index(data, index, columns)
          data = {idx: data[:, i] for i, idx in enumerate(columns)}
          return self._init_dict(data, index, columns, dtype)
docs: Init self from ndarray or list of lists.