# numpy.power

numpy.power(x1, x2, /, out=None, *, where=True, casting='same_kind', order='K', dtype=None, subok=True[, signature, extobj]) = <ufunc 'power'>

  First array elements raised to powers from second array, element-wise.

  Raise each base in x1 to the positionally-corresponding power in x2. x1 and x2 must be broadcastable to the same shape.

  An integer type raised to a negative integer power will raise a `ValueError`.

  Negative values raised to a non-integral value will return `nan`. To get complex results, cast the input to complex, or specify the `dtype` to be `complex` (see the example below).

  Parameters
    x1 array_like

      The bases.

    x2 array_like

      The exponents. If `x1.shape != x2.shape`, they must be broadcastable to a common shape (which becomes the shape of the output).

    out ndarray, None, or tuple of ndarray and None, optional

      A location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned. A tuple (possible only as a keyword argument) must have length equal to the number of outputs.

    where array_like, optional

      This condition is broadcast over the input. At locations where the condition is True, the out array will be set to the ufunc result. Elsewhere, the out array will retain its original value. Note that if an uninitialized out array is created via the default `out=None`, locations within it where the condition is False will remain uninitialized.

    **kwargs

      For other keyword-only arguments, see the ufunc docs.

  Returns
    y ndarray

      The bases in x1 raised to the exponents in x2. This is a scalar if both x1 and x2 are scalars.

  See also

  `float_power`

    power function that promotes integers to float

  Examples

  Cube each element in an array.

      >>> x1 = np.arange(6)
      >>> x1
      [0, 1, 2, 3, 4, 5]
      >>> np.power(x1, 3)
      array([  0,   1,   8,  27,  64, 125])

  Raise the bases to different exponents.

      >>> x2 = [1.0, 2.0, 3.0, 3.0, 2.0, 1.0]
      >>> np.power(x1, x2)
      array([  0.,   1.,   8.,  27.,  16.,   5.])

  The effect of broadcasting.

      >>> x2 = np.array([[1, 2, 3, 3, 2, 1], [1, 2, 3, 3, 2, 1]])
      >>> x2
      array([[1, 2, 3, 3, 2, 1],
             [1, 2, 3, 3, 2, 1]])
      >>> np.power(x1, x2)
      array([[ 0,  1,  8, 27, 16,  5],
             [ 0,  1,  8, 27, 16,  5]])

  The `**` operator can be used as a shorthand for `np.power` on ndarrays.

      >>> x2 = np.array([1, 2, 3, 3, 2, 1])
      >>> x1 = np.arange(6)
      >>> x1 ** x2
      array([ 0,  1,  8, 27, 16,  5])

  Negative values raised to a non-integral value will result in `nan` (and a warning will be generated).

      >>> x3 = np.array([-1.0, -4.0])
      >>> with np.errstate(invalid='ignore'):
      ...     p = np.power(x3, 1.5)
      ...
      >>> p
      array([nan, nan])

  To get complex results, give the argument `dtype=complex`.

      >>> np.power(x3, 1.5, dtype=complex)
      array([-1.83697020e-16-1.j, -1.46957616e-15-8.j])

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