From: "John W. Kennedy" <jwkenne@[EMAIL PROTECTED]
>
Sent: Wednesday, January 18, 2006 2:16 PM
> robin wrote:
> > "John W. Kennedy" <jwkenne@[EMAIL PROTECTED]
> wrote in message
> > news:ivXyf.40$gh5.16@[EMAIL PROTECTED]
> >> robin wrote:
> >>>>>> The 704 family offered double precision, too; it was not fully
> >>>>>> implemented in hardware, but the hardware assisted it, and the
FORTRAN
> >>>>>> compiler sup****ted it.
> >>>>> It had to, in order to meet the standard.
> >>>> There was no FORTRAN standard until long afterwards.
> >>> IBM set it.
> >> So your argument is that the 704 hardware had to implement
> >> double-precision floating-point in 1954 in order to sup****t FORTRAN
IV,
> >> which didn't even come out until 1962 (two hardware generations
later)?
> >
> > You said it ; I didn't.
>
> The bloody quotes are right above.
I think that it would be a good idea if you ceased
your ridiculous allegations, which have not been based on anything.
> >>>>>>> But for most work, little difference between 36 bits and 32
bits.
> >>>>>>> But that's no measure, anyhow. The appropriate measure is
> >>>>>>> the number of mantissa bits and range of exponent.
> >>>>>> They add up to the word size, one way or the other.
> >>>>> Not relevant; what's im****tant is the breakdown --
> >>>>> and in particular, the number of mantissa bits.
> >>>> In order to make any sense of your argument, I can only assume that
you
> >>>> do not know what the words "relevant" and "mantissa" mean. Kindly
look
> >>>> them up.
> >>> The term "mantissa" has been used since the early days of computers
> >>> to describe part of floating-point number.
> >>>
> >>> Are you having a bad day?
> >> Either you are attempting to argue that the size of the fraction and
the
> >> size of the exponent are each more im****tant than one another, while
> >> simultaneously maintaining that word size has nothing to do with the
> >> issue either way, or else you are simply misusing words.
> >
> > Are you trying to divert attention from "mantissa"?
>
> We'll try this one more time.
>
> You argue simultaneously that the "mantissa" is most im****tant and that
> the exponent is most im****tant.
If you look again, you will see that I didn't say that.
> This means one of two things: you think
> "mantissa" means "exponent", or you're contradicting yourself.
The only person who doesn't know what "mantissa" means
is your self. Do you still think that it is to do with logarithms?
And BTW, I didn't contradict myself.
> >>>>>> In any case, the
> >>>>>> S/360 had significantly fewer effective fraction bits (21) in
single
> >>>>>> precision than the 7094 (27).
> >>>>> Leaving only 7 bits for the exponent. In other words, a reduced
> >>>>> range of exponent, which the S/360 corrected.
> >>>> Having trouble with subtraction, are we now?
> >>> When I last looked, 27 + 1 + 7 + 1 = 36.
> >> Are you under the impression that the 704 series had a 35-bit word
with
> >> a parity bit?
> >
> > You said 36 bits earlier.
>
> Yes, I did, because it /did/ have 36. But your breakdown above includes
> an extra 1-bit field that cannot be accounted for.
I'll leave it for you to work out what the bits might be for.
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