code: def _mesh_values(data, box_size):
      
  
      data = np.ma.asanyarray(data)
  
      ny, nx = data.shape
      nyboxes = ny // box_size
      nxboxes = nx // box_size
  
      # include only complete boxes
      ny_crop = nyboxes * box_size
      nx_crop = nxboxes * box_size
      data = data[0:ny_crop, 0:nx_crop]
  
      # a reshaped 2D masked array with mesh data along the x axis
      data = np.ma.swapaxes(data.reshape(
          nyboxes, box_size, nxboxes, box_size), 1, 2).reshape(
              nyboxes * nxboxes, box_size * box_size)
  
      # include only boxes without any masked pixels
      idx = np.where(np.ma.count_masked(data, axis=1) == 0)
  
      return data[idx]
docs: Extract all the data values in boxes of size ``box_size``.
  
      Values from incomplete boxes, either because of the image edges or
      masked pixels, are not returned.
  
      Parameters
      ----------
      data : 2D `~numpy.ma.MaskedArray`
          The input masked array.
  
      box_size : int
          The box size.
  
      Returns
      -------
      result : 2D `~numpy.ndarray`
          A 2D array containing the data values in the boxes (along the x
          axis).