The notion that input data are not in an internal floating-point
format, be it BFP, DFP, or HFP, is unarguable.  This is also true of
binary integers.  Indeed there is our at least should always be a
distinction between external. displayable|printable values and
internal, coimputationally convenient.

Some of the input data I work with are in classical engineering notation, e.g.,

+1.414213256237309504880e+000,

Some are external fixed-point, e.g.,

+1.414213256237309504880,

some are external integers, e.g.,

-5,

and some are pairs (a,b) of one of these that represent the complex
number a + bi.

They are all converted into the appropriate internal format, readily,
and stored as such in files or RDBs.  Conversions occur only at input
and output, display or report preparation.

Thus

<begin extract>
To go from character string to a format that can then be converted to
DFP requires, at the least, a PACK instruction.
</end extract>

is almost aways an entirely correct but unproblematic truism.  (There
is an ancient model of a computer system that is said to  1) read in
an integer augend, 2) add anoither integer added to it, and 3) output
the resulting sum; and for such 'systems' many conversions may be
intolerably burdensome; but such systems are not really of much
interest.)

I, and I am not alone in this, find the idea of doing arithmetic on
display values absurd.  COBOL notionally permits this, but only by
sleight of hand.  The to-and-fro conversions are hidden away in
library subroutines.

John Gilmore, Ashland, MA 01721 - USA

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