megengine.functional.acosh#

acosh(x)[source]#

Element-wise \(\cosh^{-1}(x)\) function.

Calculates the inverse hyperbolic cosine for each element \(x_i\) of the input tensor \(x\).

This function has domain [1, +infinity] and codomain [0, +infinity].

Special cases

For floating-point operands,

  • If \(x_i\) is NaN, the result is NaN.

  • If \(x_i\) is less than 1, the result is NaN.

  • If \(x_i\) is 1, the result is +0.

  • If \(x_i\) is +infinity, the result is +infinity.

Parameters:

x – input tensor whose elements each represent the area of a hyperbolic sector. Should have a floating-point data type.

Returns:

a tensor containing the inverse hyperbolic cosine of each element in \(x\). The returned tensor must have a floating-point data type determined by Type promotion rules.

Examples

>>> F.acosh(1)
Tensor(0.0, device=xpux:0)

Element-wise inverse hyperbolic cosine:

>>> x = Tensor([1, 2, 3])
>>> F.acosh(x)
Tensor([0.     1.317  1.7627], device=xpux:0)