code: def _from_arrays(self, x, y, z):
          
          x = np.unique(x.ravel())
          y = np.unique(y.ravel())
          z = np.unique(z.ravel())
          # Set the cell spacings and dimensions of the grid
          self.SetDimensions(len(x), len(y), len(z))
          self.SetXCoordinates(numpy_to_vtk(x))
          self.SetYCoordinates(numpy_to_vtk(y))
          self.SetZCoordinates(numpy_to_vtk(z))
docs: Create VTK rectilinear grid directly from numpy arrays. Each array
          gives the uniques coordinates of the mesh along each axial direction.
          To help ensure you are using this correctly, we take the unique values
          of each argument.
  
          Parameters
          ----------
          x : np.ndarray
              Coordinates of the nodes in x direction.
  
          y : np.ndarray
              Coordinates of the nodes in y direction.
  
          z : np.ndarray
              Coordinates of the nodes in z direction.