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.
>>>>>>> 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. This means one of two things: you think
"mantissa" means "exponent", or you're contradicting yourself.
>>>>>> 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.
--
John W. Kennedy
"But now is a new thing which is very old--
that the rich make themselves richer and not poorer,
which is the true Gospel, for the poor's sake."
-- Charles Williams. "Judgement at Chelmsford"
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