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
.Notes
Complex dtypes are not supported, they will raise a TypeError.
ldexp
is useful as the inverse offrexp
, if used by itself it is more clear to simply use the expressionx1 * 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.])