ZealOS has a class for 3 dimensional points consisting of F64s.  ZealC is not C++ -- it does not support passing or returning 
values from functions which are not 64-bits, therefore, it can't be implemented with operator overloading.  Making all 
function args and returns 64-bit is a core prinicple of ZealOS.

As a courtesy, most of the CD3 functions return the address of the destination vect, so you can nestle calls.   They do not 
alloc new space for the destination vect.