code: def _call_fornav(self, cols, rows, target_geo_def, data,
                       grid_coverage=0, **kwargs):
          
          num_valid_points, res = fornav(cols, rows, target_geo_def,
                                         data, **kwargs)
  
          if isinstance(data, tuple):
              # convert 'res' from tuple of arrays to one array
              res = np.stack(res)
              num_valid_points = sum(num_valid_points)
  
          grid_covered_ratio = num_valid_points / float(res.size)
          grid_covered = grid_covered_ratio > grid_coverage
          if not grid_covered:
              msg = "EWA resampling only found %f%% of the grid covered " \
                    "(need %f%%)" % (grid_covered_ratio * 100,
                                     grid_coverage * 100)
              raise RuntimeError(msg)
          LOG.debug("EWA resampling found %f%% of the grid covered" %
                    (grid_covered_ratio * 100))
  
          return res
docs: Wrapper to run fornav as a dask delayed.