[TUHS] History of m6?

Bakul Shah bakul at bitblocks.com
Mon Nov 18 04:12:28 AEST 2019

On Sat, 16 Nov 2019 21:50:58 -0800 Larry McVoy <lm at mcvoy.com> wrote:
Larry McVoy writes:
> On Sun, Nov 17, 2019 at 04:30:15PM +1100, Dave Horsfall wrote:
> > On Sat, 16 Nov 2019, SPC wrote:
> > 
> > >My first FORTRAN textbook was titled "FORTRAN with WATFOR and WATFIV". It
> > >had a long print run as well.
> > 
> > Now *that* brings back memories (not necessarily pleasant).  WATFOR was as
> > ugly as sin
> I'm pretty sure that was the Fortran I learned.  Yeah, it was not C.  But
> it was math.  I spent a bunch of time learning accumulated errors and 
> more time on floating point numbers.  My dad was a theoretical physics
> guy so I did some coding for him.  I respected Fortran for what it could
> do but I developed a hate for floating point.  In my mind, floating
> point numbers meant you couldn't handle the world you were working in.
> It just felt like you could shift the domain you were working in so
> integers could work.  If you couldn't do that, you were admitting that
> you were not accurate.

Many numbers can't be represented perfectly using integers or
rationals (a pair of integers) but can be computed using a
series expansion to arbitrary precision.  I thought FP numbers
were a clever & practical compromise that worked quite well.
David Goldberg's "What every computer scientist should know
about floating-point" is worth reading.

Earlier I remember reading the "Numerical Recipes" books by
Press, Teukolsky, Vetterling & Flannery. IIRC, the original
version used Fortran.  They also had versions using Pascal and
C (I finally bought the C version in '80s though never used it).

Note that Scheme & CL have a full complement of numeric types:
big nums, rationals, reals and complex numbers.  At least some
versions of CL have arbitrary precision FP numbers.

What I really want is a programming language with support for
symbolic manipulation of formulas!

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