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# numpy.ma.set_fill_value

ma.set_fill_value(a, fill_value)

  Set the filling value of a, if a is a masked array.

  This function changes the fill value of the masked array a in place. If a is not a masked array, the function returns silently, without doing anything.

  Parameters:
    a array_like

      Input array.

    fill_value dtype

      Filling value. A consistency test is performed to make sure the value is compatible with the dtype of a.

  Returns:
    None

      Nothing returned by this function.

  See also

  `maximum_fill_value`

    Return the default fill value for a dtype.

  `MaskedArray.fill_value`

    Return current fill value.

  `MaskedArray.set_fill_value`

    Equivalent method.

  Examples

      >>> import numpy as np
      >>> import numpy.ma as ma
      >>> a = np.arange(5)
      >>> a
      array([0, 1, 2, 3, 4])
      >>> a = ma.masked_where(a < 3, a)
      >>> a
      masked_array(data=[--, --, --, 3, 4],
                   mask=[ True,  True,  True, False, False],
             fill_value=999999)
      >>> ma.set_fill_value(a, -999)
      >>> a
      masked_array(data=[--, --, --, 3, 4],
                   mask=[ True,  True,  True, False, False],
             fill_value=-999)

  Nothing happens if a is not a masked array.

      >>> a = list(range(5))
      >>> a
      [0, 1, 2, 3, 4]
      >>> ma.set_fill_value(a, 100)
      >>> a
      [0, 1, 2, 3, 4]
      >>> a = np.arange(5)
      >>> a
      array([0, 1, 2, 3, 4])
      >>> ma.set_fill_value(a, 100)
      >>> a
      array([0, 1, 2, 3, 4])