Re: Multiplying fixed-point by long integer

[anon@att.net]

An old discussion mostly bwtween the 1980s and 90s.

A file "farith.c" 

/*
 * multi-precision multiplication, division and exponentiation
 * for fixed point computations.
 */
 ...

which is a componet of "Ada/Ed" package that uses the "Multiple Precision 
Integer Arithetic Package" written by Robert B. K. Dewar in June 16, 1980. 
To preform some of the arithmetic calculations used in the "Ada/Ed" system.



Do a Google search for url of a ftp link to file using keywords

   multi-precision arithmetic "Robert B. K. Dewar" Ada/Ed farith.c


Other discussion on this subject can be found by just google and added 
the name Robert B. K. Dewar. Most will be between 1980 and 1999.


In <b06c0b56-3f3c-42e9-8b3a-76a4a27fc1cc@googlegroups.com>, Adam Beneschan <adam@irvine.com> writes:
>I don't think I've ever seen this problem discussed before ...
>
>4.5.5 defines predefined multiplication operators between any fixed-point t=
>ype and Integer.  However, it isn't defined for any other integer type.  Th=
>is can cause a problem if I have an integer type whose bounds are larger th=
>an Integer, since it obviously won't work to convert it to Integer.  Has an=
>yone encountered this problem before, and how did you solve it?  I'm hesita=
>nt to try to solve it by converting things to floating point, since the man=
>tissa of a floating-point may have fewer bits than the fixed-point or integ=
>er type, and fixed-point multiplication by an integer should be exact.
>
>                                 -- thanks, Adam