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# pandas.Index.to_numpy

Index.to_numpy(dtype=None, copy=False, na_value=<no_default>, **kwargs)

  A NumPy ndarray representing the values in this Series or Index.

  Parameters:
    dtype str or numpy.dtype, optional

      The dtype to pass to `numpy.asarray()`.

    copy bool, default False

      Whether to ensure that the returned value is not a view on another array. Note that `copy=False` does not ensure that `to_numpy()` is no-copy. Rather, `copy=True` ensure that a copy is made, even if not strictly necessary.

    na_value Any, optional

      The value to use for missing values. The default value depends on dtype and the type of the array.

    **kwargs

      Additional keywords passed through to the `to_numpy` method of the underlying array (for extension arrays).

  Returns:
    numpy.ndarray

      The NumPy ndarray holding the values from this Series or Index. The dtype of the array may differ. See Notes.

  See also

  `Series.array`

    Get the actual data stored within.

  `Index.array`

    Get the actual data stored within.

  `DataFrame.to_numpy`

    Similar method for DataFrame.

  Notes

  The returned array will be the same up to equality (values equal in self will be equal in the returned array; likewise for values that are not equal). When self contains an ExtensionArray, the dtype may be different. For example, for a category-dtype Series, `to_numpy()` will return a NumPy array and the categorical dtype will be lost.

  For NumPy dtypes, this will be a reference to the actual data stored in this Series or Index (assuming `copy=False`). Modifying the result in place will modify the data stored in the Series or Index (not that we recommend doing that).

  For extension types, `to_numpy()` may require copying data and coercing the result to a NumPy type (possibly object), which may be expensive. When you need a no-copy reference to the underlying data, `Series.array` should be used instead.

  This table lays out the different dtypes and default return types of `to_numpy()` for various dtypes within pandas.

  dtype | array type
  --- | ---
  category[T] | ndarray[T] (same dtype as input)
  period | ndarray[object] (Periods)
  interval | ndarray[object] (Intervals)
  IntegerNA | ndarray[object]
  datetime64[ns] | datetime64[ns]
  datetime64[ns, tz] | ndarray[object] (Timestamps)

  Examples

      >>> ser = pd.Series(pd.Categorical(["a", "b", "a"]))
      >>> ser.to_numpy()
      array(['a', 'b', 'a'], dtype=object)

  Specify the dtype to control how datetime-aware data is represented. Use `dtype=object` to return an ndarray of pandas `Timestamp` objects, each with the correct `tz`.

      >>> ser = pd.Series(pd.date_range("2000", periods=2, tz="CET"))
      >>> ser.to_numpy(dtype=object)
      array([Timestamp('2000-01-01 00:00:00+0100', tz='CET'),
             Timestamp('2000-01-02 00:00:00+0100', tz='CET')],
            dtype=object)

  Or `dtype='datetime64[ns]'` to return an ndarray of native datetime64 values. The values are converted to UTC and the timezone info is dropped.

      >>> ser.to_numpy(dtype="datetime64[ns]")
      ...
      array(['1999-12-31T23:00:00.000000000', '2000-01-01T23:00:00...'],
            dtype='datetime64[ns]')