- `Y = coth (X)`

Compute the hyperbolic cotangent of each element of `X`.

This is defined as

> > `%coth(z) = cosh(z)/sinh(z)%`

See also: `acoth`.

### References

- https://www.mathworks.com/help/matlab/ref/coth.html
- https://octave.sourceforge.io/octave/function/coth.html
- https://mathworld.wolfram.com/HyperbolicFunctions.html
- https://en.wikipedia.org/wiki/Hyperbolic_functions