Provides methods that permit use of floating-point numbers of arbitrary length. The following apply to all methods, except as noted:
The object $f remains unchanged.
All methods except fcmp return a number string (nstr)
of the form
/[+-]\d+E[+-]\d+/, with embedded whitespace ignored.
A return value of NaN indicates either that an input parameter was "Not
a Number" or that an illegal operation was attempted.
A similar default scale value is computed for square roots.