coshm matrix hyperbolic cosine

## Syntax

    t = coshm(x)

## Arguments

x, t

  real or complex square matrices.

## Description

`coshm` is the matrix hyperbolic cosine of the matrix `x`. `t=(expm(x)+expm(-x))/2`. Result may be inaccurate for nonsymmetric matrix.

## Examples

    A=[1,2;2,4]
    acoshm(coshm(A))

## See also

- cosh
- expm