mindspore.ops.bessel_k1

mindspore.ops.bessel_k1(x)

Computes modified Bessel function of the second kind, order 1 element-wise.

The formula is defined as:

$$\begin{array}{r}\begin{array}{l}\\ K_1(x)=\underset{\nu \to 1}{lim}\left(\frac{\pi }{2}\right)\frac{I_{-\nu }(x)-I_{\nu }(x)}{\sin (\nu \pi )}={\int }_0^{\mathrm{\infty }}{e}^{-x\cosh t}\cosh (t)dt\end{array}\end{array}$$

where $I_1$ is modified Bessel function of the first kind, order 1.

Parameters

x (Tensor) – The input tensor. The data type must be float16, float32 or float64.

Returns

Tensor, has the same shape and dtype as the x.

Raises

• TypeError – If x is not a Tensor.

• TypeError – If dtype of x is not float16, float32 or float64.

Supported Platforms:

GPU CPU

Examples

>>> import mindspore
>>> import numpy as np
>>> from mindspore import Tensor, ops
>>> x = Tensor(np.array([0.5, 1., 2., 4.]), mindspore.float32)
>>> output = ops.bessel_k1(x)
>>> print(output)
[1.65644112  0.60190723  0.13986588  0.0124835]