* Continue MathTrig Breakup - Trig Functions
Continuing the process of breaking MathTrip.php up into smaller classes.
This round takes care of the trig and hyperbolic functions, plus a few others.
- COS, COSH, ACOS, ACOSH
- COT, COTH, ACOT, ACOTH
- CSC, CSCH
- SEC, SECH
- SIN, SINH, ASIN, ASINH
- TAN, TANH, ATAN, ATANH, ATAN2
- EVEN
- ODD
- SIGN
There are no bug fixes in this PR, except that boolean arguments are now
accepted for all these functions, as they are for Excel.
Taking a cue from what has been done in Engineering, the parameter validation
now happens in a routine which issues Exceptions for invalid values;
this simplifies the code in the functions themselves.
Consistent with earlier changes of this nature, the versions in the
MathTrig class remain, with a doc block indicating deprecation,
and a stub call to the new routines.
I think several more iterations will be needed to break up MathTrig completely.