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# numpy.ldexp

`numpy.``ldexp`(x1, x2[, out]) = <ufunc 'ldexp'>

  Returns x1 * 2**x2, element-wise.

  The mantissas x1 and twos exponents x2 are used to construct floating point numbers `x1 * 2**x2`.

  Parameters : | x1 : array_like Array of multipliers. x2 : array_like, int Array of twos exponents. out : ndarray, optional Output array for the result.
  Returns : | y : ndarray or scalar The result of `x1 * 2**x2`.

  See also

  `frexp`
    Return (y1, y2) from `x = y1 * 2**y2`, inverse to `ldexp`.

  Notes

  Complex dtypes are not supported, they will raise a TypeError.

  `ldexp` is useful as the inverse of `frexp`, if used by itself it is more clear to simply use the expression `x1 * 2**x2`.

  Examples

      >>> np.ldexp(5, np.arange(4))
      array([  5.,  10.,  20.,  40.], dtype=float32)

      >>> x = np.arange(6)
      >>> np.ldexp(*np.frexp(x))
      array([ 0.,  1.,  2.,  3.,  4.,  5.])