# mars.tensor.arcsinh#

mars.tensor.arcsinh(x, out=None, where=None, **kwargs)[source]#

Inverse hyperbolic sine element-wise.

Parameters
• x (array_like) – Input tensor.

• out (Tensor, None, or tuple of Tensor 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 tensor is returned. A tuple (possible only as a keyword argument) must have length equal to the number of outputs.

• where (array_like, optional) – Values of True indicate to calculate the ufunc at that position, values of False indicate to leave the value in the output alone.

• **kwargs

Returns

out – Tensor of of the same shape as x.

Return type

Tensor

Notes

arcsinh is a multivalued function: for each x there are infinitely many numbers z such that sinh(z) = x. The convention is to return the z whose imaginary part lies in [-pi/2, pi/2].

For real-valued input data types, arcsinh always returns real output. For each value that cannot be expressed as a real number or infinity, it returns `nan` and sets the invalid floating point error flag.

For complex-valued input, arccos is a complex analytical function that has branch cuts [1j, infj] and [-1j, -infj] and is continuous from the right on the former and from the left on the latter.

The inverse hyperbolic sine is also known as asinh or `sinh^-1`.

References

1

M. Abramowitz and I.A. Stegun, “Handbook of Mathematical Functions”, 10th printing, 1964, pp. 86. http://www.math.sfu.ca/~cbm/aands/

2

Wikipedia, “Inverse hyperbolic function”, http://en.wikipedia.org/wiki/Arcsinh

Examples

```>>> import mars.tensor as mt
```
```>>> mt.arcsinh(mt.array([mt.e, 10.0])).execute()
array([ 1.72538256,  2.99822295])
```