# $EPIC: cosh.txt,v 1.3 2006/07/24 19:50:14 sthalik Exp $
Returns the hyperbolic cosine of <number>.
If the <number> argument is omitted the empty string is returned.
As always, the return value is limited to 6 decimal places.
As always, DOM or RANGE means there was an error.
The hyperbolic cosine of an angle