dpnp.expm1

dpnp.expm1(x, out=None, where=True, order='K', dtype=None, subok=True, **kwargs)

Computes the exponential minus 1 for each element \(x_i\) of input array x.

For full documentation refer to numpy.expm1.

Parameters:

  • x ({dpnp.ndarray, usm_ndarray}) -- Input array, expected to have a floating-point data type.

  • out ({None, dpnp.ndarray, usm_ndarray}, optional) --

    Output array to populate. Array must have the correct shape and the expected data type.

    Default: None.

  • order ({None, "C", "F", "A", "K"}, optional) --

    Memory layout of the newly output array, if parameter out is None.

    Default: "K".

Returns:

out -- An array containing containing the evaluated result for each element in x. The data type of the returned array is determined by the Type Promotion Rules.

Return type:

dpnp.ndarray

Limitations

Parameters where and subok are supported with their default values. Keyword argument kwargs is currently unsupported. Otherwise NotImplementedError exception will be raised.

See also

dpnp.exp

Calculate \(e^x\), element-wise.

dpnp.exp2

Calculate \(2^x\), element-wise.

dpnp.log1p

Calculate \(\log(1 + x)\), element-wise, the inverse of dpnp.expm1.

Notes

This function provides greater precision than \(e^x - 1\) for small values of x.

Examples

>>> import dpnp as np
>>> x = np.arange(3.)
>>> np.expm1(x)
array([0.0, 1.718281828, 6.389056099])

>>> np.expm1(np.array(1e-10))
array(1.00000000005e-10)

>>> np.exp(np.array(1e-10)) - 1
array(1.000000082740371e-10)