Re: negative zero
robin
| Arjen Markus <arjen.m...@gmail.com> wrote:
| (snip)
|
| > The reason a signed zero exists, as far as I can tell, is that for
| > certain computations with complex numbers it is important
| > to be able to distinguish numbers on either side of a branch cut.
| > (see http://mathworld.wolfram.com/RiemannSurface.html for instance)
|
| Well, the reason it exists is that it comes natually with sign
| magnitude and ones complement representation. Most early computers
| used sign magnitude, and slightly later ones complement for integers.
The reason that most early computers DIDN'T use ones
complement was that execution time for arithmetic operations
would have been doubled or more.
Most of the early computers were serial, and the problem with
ones complement addition was that if there is a carry out
of the addition, a 'one" must THEN be added into the result --
thus requiring TWO additions. In a serial machine, the arithmetic
proceeds from the least-significant bit, one bit at a time. By the time that
a carry out has occurred and been detected, the word has gone, and
the addition operation must then be repeated, by bringing back the sum
to the adder, and adding a "one". Thus, two additions!
For signed-magnitude, similar difficulties exist,
depending on whether the result of addition is negative or positive.
| It turned out, though, that twos complement is a better choice
| for fixed point,
It didn't "turn out" better.
Before building any computer, designers had already determined
that TWOS-COMPLEMENT was the ONLY choice for
a binary arithmetic unit.
| but sign magnitude seems to work best for
| floating point.
Are you forgetting that CDC 6000 series and later used
ones complement floating-point?
robin
news:4c99e35d$1$fuzhry+tra$mr2...@news.patriot.net...
| In <4c995639$0$90005$c30e...@exi-reader.telstra.net>, on 09/22/2010
| at 11:04 AM, "robin" <rob...@dodo.com.au> said:
|
| >The reason that most early computers DIDN'T use ones
| >complement was that execution time for arithmetic operations would
| >have been doubled or more.
|
You don't know what youare taling about.
| >Most of the early computers were serial,
|
| 1940's, perhaps, certainly not 1950's.
Definitely in the 1950s.
| >For signed-magnitude, similar difficulties exist,
|
| And for anything but ones' complement, negating a number requires
| going through the adder instead of just a bunch on not gates.
To form the negative in a serial machine, it was necessary to subtract it from zero.
Even if ones complement was used for such a machine (which it wasn't),
all the bits in the word would have had to pass thru the adder/complementer,
and would have taken the same time as forming the twos complement.
| >Before building any computer, designers had already determined that
| >TWOS-COMPLEMENT was the ONLY choice for
| >a binary arithmetic unit.
|
| In what universe?
In a serial machine, as already stated.
John W Kennedy
> "Shmuel (Seymour J.) Metz" <spam...@library.lspace.org.invalid> wrote
> in message
> news:4c99e35d$1$fuzhry+tra$mr2...@news.patriot.net...
> | In <4c995639$0$90005$c30e...@exi-reader.telstra.net>, on 09/22/2010
> | at 11:04 AM, "robin" <rob...@dodo.com.au> said:
> |
> | >The reason that most early computers DIDN'T use ones
> | >complement was that execution time for arithmetic operations would
> | >have been doubled or more.
> |
> | Nonsense.
>
> You don't know what youare taling about.
>
> | >Most of the early computers were serial,
> |
> | 1940's, perhaps, certainly not 1950's.
>
> Definitely in the 1950s.
None that I know of. Certainly not any production machine from IBM,
who, by the way, first used twos-complement in the S/360 (1964).
--
John W Kennedy
"The grand art mastered the thudding hammer of Thor
And the heart of our lord Taliessin determined the war."
-- Charles Williams. "Mount Badon"
glen herrmannsfeldt
>> Definitely in the 1950s.
> None that I know of. Certainly not any production machine from IBM,
> who, by the way, first used twos-complement in the S/360 (1964).
The machines leading up to S/360, from the 704 through the 7090,
are all sign magnitude.
I have wondered about a C compiler for such so that we can test
the fact that the C standard still allows for such machines.
Many early machines were decimal, usually sign magnitude, but
maybe some nines-complement around somewhere.
Well, even earlier were mechanical machines, which may have been
called adding machines, or mechanical calculators, and often
based on rotating disks representing decimal digits. As obvious
as binary is to us now, it wasn't so obvious at the time.
Some early electronic machines may have been implemented based
on the designs of mechanical calculators.
-- glen
John W Kennedy
> John W Kennedy <jwk...@attglobal.net> wrote:
>> On 2010-09-22 07:28:56 -0400, robin said:
> (snip regarding twos complement)
>
>>> Definitely in the 1950s.
>
>> None that I know of. Certainly not any production machine from IBM,
>> who, by the way, first used twos-complement in the S/360 (1964).
>
> The machines leading up to S/360, from the 704 through the 7090,
> are all sign magnitude.
And so was the 701 (precursor of the 704, with an 18-bit word), and so
was the 7030 ("Stretch"). All the other pre-360 IBM production lines:
702/705/7080, 650/707x, 610, 305, 14xx/7010, and 1620 were decimal, as
was, surprisingly, NORC. (SAGE was binary, but the Whirlwind
architecture underlying it was developed by MIT, not IBM. It was, for
what it's worth, parallel, and sign-magnitude.)
Robin is partly right; many machines of the 1940s were serial-by-bit,
and perhaps they may have used twos-complement, for aught I know to the
contrary, though I cannot name one that did. But serial-by-bit was
obsolete by the 1950s -- IBM never used it except for the Tape
Processing Machine (TPM), a one-off, in-house prototype for the 702.
robin
news:4c99e35d$1$fuzhry+tra$mr2...@news.patriot.net...
| >Most of the early computers were serial,
|
| 1940's, perhaps, certainly not 1950's.
The Bendix G15, of which 400 were sold,
began operations in 1956. It was a serial machine.
The DEUCE was serial, commenced operation in
1955.
The ACE was serial, commenced operation in late 1950s.
UNIVAC I and UNIVAC II were serial.
In fact, a whole heap of serial machines was produced in the early years.
Choice of serial was based on the type of storage medium
(typcally acoustic delay lines, but could be magnetic), and of the need to
minimise equipment.
Thus, early (serial) machines got by with some 1000 vacuum tubes
(compare with 18,000 for ENIAC).
(Parallel was expensive in hardware, requiring an adder
having some 32 adder circuits instead of 1 for serial.)
robin
| And so was the 701 (precursor of the 704, with an 18-bit word), and so
| was the 7030 ("Stretch"). All the other pre-360 IBM production lines:
| 702/705/7080, 650/707x, 610, 305, 14xx/7010, and 1620 were decimal, as
| was, surprisingly, NORC. (SAGE was binary, but the Whirlwind
| architecture underlying it was developed by MIT, not IBM. It was, for
| what it's worth, parallel, and sign-magnitude.)
|
| Robin is partly right; many machines of the 1940s were serial-by-bit,
and the 1950s.
Take a look at the family tree of computers, and tell me how many
dirrerent serial computers you can see.
| and perhaps they may have used twos-complement, for aught I know to the
| contrary, though I cannot name one that did. But serial-by-bit was
| obsolete by the 1950s
Perhaps obsolete, but nevertheless new serial designs were being introduced.
In the US, the Bendix G15 was first delivered in 1956.
And Pilot ACE, ACE, and DEUCE were twos complement.
As I said elsewhere, serial machines typically used acoustic delay lines,
though the G15 used a drum.
glen herrmannsfeldt
> "Shmuel (Seymour J.) Metz" <spam...@library.lspace.org.invalid> wrote in message
> The Bendix G15, of which 400 were sold,
> began operations in 1956. It was a serial machine.
> The DEUCE was serial, commenced operation in 1955.
> The ACE was serial, commenced operation in late 1950s.
> UNIVAC I and UNIVAC II were serial.
> In fact, a whole heap of serial machines was produced in the early years.
Weren't some of these serial decimal, that is, one decimal
digit at a time? Not quite bit serial as we would expect now.
-- glen
John W Kennedy
> "Shmuel (Seymour J.) Metz" <spam...@library.lspace.org.invalid> wrote
> in message
> news:4c99e35d$1$fuzhry+tra$mr2...@news.patriot.net...
>
> | >Most of the early computers were serial,
> |
> | 1940's, perhaps, certainly not 1950's.
>
> The Bendix G15, of which 400 were sold,
> began operations in 1956. It was a serial machine.
>
> The DEUCE was serial, commenced operation in
> 1955.
>
> The ACE was serial, commenced operation in late 1950s.
1950. And the DEUCE and the G-15 were both ACE derivatives. All three
were, in effect, minicomputers; the ACE has even been proposed for the
role of "first personal computer".
> UNIVAC I and UNIVAC II were serial.
They were also decimal, and therefore irrelevant.
> In fact, a whole heap of serial machines was produced in the early years.
You've given us one, plus two follow-ons.
> Choice of serial was based on the type of storage medium
> (typcally acoustic delay lines, but could be magnetic), and of the need to
> minimise equipment.
>
> Thus, early (serial) machines got by with some 1000 vacuum tubes
> (compare with 18,000 for ENIAC).
>
> (Parallel was expensive in hardware, requiring an adder
> having some 32 adder circuits instead of 1 for serial.)
IBM found that the parallel 702 was actually less expensive than the
serial Tape Processing Machine had been. (Both used Williams tubes for
main memory.)
glen herrmannsfeldt
(snip)
>> UNIVAC I and UNIVAC II were serial.
> They were also decimal, and therefore irrelevant.
Not completely irrelevant...
besides, serial decimal machines, usually called calculators,
are still popular today.
-- glen
John W Kennedy
> John W Kennedy <jwk...@attglobal.net> wrote:
> (snip)
>
>>> UNIVAC I and UNIVAC II were serial.
>
>> They were also decimal, and therefore irrelevant.
>
> Not completely irrelevant...
Irrelevant to the issue of twos-complement.
robin
| On 2010-09-22 22:39:25 -0400, robin said:
|
| > "Shmuel (Seymour J.) Metz" <spam...@library.lspace.org.invalid> wrote
| > in message
| > news:4c99e35d$1$fuzhry+tra$mr2...@news.patriot.net...
| >
| > | >Most of the early computers were serial,
| > |
| > | 1940's, perhaps, certainly not 1950's.
| >
| > The Bendix G15, of which 400 were sold,
| > began operations in 1956. It was a serial machine.
| >
| > The DEUCE was serial, commenced operation in
| > 1955.
| >
| > The ACE was serial, commenced operation in late 1950s.
|
| 1950.
Construction of ACE commenced in 1954, and operation commenced in 1958.
| And the DEUCE and the G-15 were both ACE derivatives. All three
| were, in effect, minicomputers; the ACE has even been proposed for the
| role of "first personal computer".
Don't be ridiculous.
The ACE was a physically huge machine, even larger than
Pilot ACE and DEUCE.
The Bendix G-15 was a physically small maachine,
about the size of a large refrigerator, and it is the G-15
that was suggested as being the first personal computer.
You have confused the ACE and Pilot ACE.
Neither the Pilot ACE, DEUCE not ACE were "mini-computers".
| > UNIVAC I and UNIVAC II were serial.
|
| They were also decimal, and therefore irrelevant.
|
| > In fact, a whole heap of serial machines was produced in the early years.
|
| You've given us one, plus two follow-ons.
Go take a look at the family tree of computers.
robin
|
| > "Shmuel (Seymour J.) Metz" <spam...@library.lspace.org.invalid> wrote
| > in message
| > news:4c99e35d$1$fuzhry+tra$mr2...@news.patriot.net...
| >
| > | >Most of the early computers were serial,
| > |
| > | 1940's, perhaps, certainly not 1950's.
| >
| > The Bendix G15, of which 400 were sold,
| > began operations in 1956. It was a serial machine.
| >
| > The DEUCE was serial, commenced operation in
| > 1955.
| >
| > The ACE was serial, commenced operation in late 1950s.
|
| 1950.
Construction of ACE commenced in 1954, and operation commenced in 1958.
| And the DEUCE and the G-15 were both ACE derivatives. All three
| were, in effect, minicomputers; the ACE has even been proposed for the
| role of "first personal computer".
Don't be ridiculous.
The ACE was a physically huge machine, even larger than
Pilot ACE and DEUCE.
The Bendix G-15 was a physically small maachine,
about the size of a large refrigerator, and it is the G-15
that was suggested as being the first personal computer.
You have confused the ACE and Pilot ACE.
Neither the Pilot ACE, DEUCE nor ACE were "mini-computers".
| > UNIVAC I and UNIVAC II were serial.
|
| They were also decimal, and therefore irrelevant.
|
| > In fact, a whole heap of serial machines was produced in the early years.
|
| You've given us one, plus two follow-ons.
Go take a look at the family tree of computers.
robin
Pilot ACE first ran in 1950.
DEUCE was first delived in 1955
ACE commisioned in 1958
Bendix G-15 deliveries commenced in 1856.
James J. Weinkam
John W Kennedy
Go take a look at the definition of "burden of proof".
robin
I don't have to prove anything. It's all there in the literature.
I have already cited the family tree of computers.
Did you look it up?
This has been republished a number of times since it firat
appeared in the c. 1960s.
As for you, you have made a number of erroneous claims
about the computers that I previously mentioned,
and I have corrected your mistakes.
robin
| In <4c99e87f$0$90003$c30e...@exi-reader.telstra.net>, on 09/22/2010| ROTF,LMAO! I may not khow what I am taling (sic) about, but I
| certainly know what I am talking about, and the binary machines of the
| 1950s were dominated by parallel ones.
You've not mentioned a single computer that did not use serial arithmetic
and/or did not use non-serial mamory.
Looks like you still don't know what you are talking about.
| >Definitely in the 1950s.
|
| FSVO "1050's" that excludes most of them.
Instead of making silly arrogant remarks,
why not actually check it out?
| >To form the negative in a serial machine,
|
| K3wl. Unfortunately, bit-serial machines were rare in the 1950's.
BTW, the IBM 701 (1952) had a bit-serial memory,
as did all machines that used the Williams tube for memory.
Althought the Ferranti Meg (1954) was a parallel machine,
it used a serial arithmetic unit.
Likewise the MV950 (1956) had a serial arithmetic unit.
As for your fatuous statement that bit-serial machines were rare in the 1950s,
I think that you have not looked at those serial computers that I already cited.
robin
| Arjen Markus <arjen.m...@gmail.com> wrote:
| (snip)
|
| > The reason a signed zero exists, as far as I can tell, is that for
| > certain computations with complex numbers it is important
| > to be able to distinguish numbers on either side of a branch cut.
| > (see http://mathworld.wolfram.com/RiemannSurface.html for instance)
|
| Well, the reason it exists is that it comes natually with sign
| magnitude and ones complement representation. Most early computers
| used sign magnitude, and slightly later ones complement for integers.
Expanding the record of serial computers using
twos complement arithmetic:-
Pilot ACE first ran in 1950.
DEUCE was first delived in 1955
ACE commissioned in 1958
Bendix G-15 deliveries commenced in 1856
Pegasus (1956)
Ferranti Mark I (1951)
Other serial machines and/or machines having serial arithmetic units :--
Ferranti Meg (1954) serial arithmetic unit.
MV950 (1956) serial arithmetic unit
ORDFIAC used serial acoustic memory.
SEAC used acoustic and electrostatic mamories.
RAYDAC (1953) used serial memory.
OARAC (1953) used serial and parallel arithmetic.
For others, see "Computer Structures, Readings and Examples".
robin
| And for anything but ones' complement, negating a number requires
| going through the adder instead of just a bunch on not gates.
Forming the twos complement in a serial machine
does not require "going through the adder".
For a number held in twos complement form, forming the negative
requires complementing all bits, starting after the first one-bit.
(recall that in a serial machine, the bits are presented
starting with the least-significant bit).
To form the ones complement in a serial machine
requires that each bit is complemented as it passes the inverter (negator) gate.
(N.B. Only one gate is required, not "a bunch on [sic] not gates".
The principles of serial machines and serial arithmetic
were established by Alan Turing back in 1945.
robin
| In <4c9abde5$0$90003$c30e...@exi-reader.telstra.net>, on 09/23/2010
| at 12:39 PM, "robin" <rob...@dodo.com.au> said:
|
| >The Bendix G15, of which 400 were sold,
| >began operations in 1956. It was a serial machine.
|
Obviously you can't read either.
Where can you find the word "most" in the above sentence
(hint: start from "The Bendix ...")?
| >(Parallel was expensive in hardware, requiring an adder having some
| >32 adder circuits instead of 1 for serial.)
|
| How did Univac manage to do an ALU for a 36-bit machine using only 30
| adder circuits?
What machine?
How did manufacturers of a serial machine manage to do it in a single
adder circuit?
John W Kennedy
> BTW, the IBM 701 (1952) had a bit-serial memory,
> as did all machines that used the Williams tube for memory.
Actually, no, it didn't. Communication with the 706 Williams-tube unit
was in parallel, and the 706 itself operated in parallel, distributing
each 36-bit word across 36 tubes. (By the way, the memory was soon
superseded by the same 737 magnetic-core unit used on the 704 and 709.)
Red Rooster
wrote:
>Bendix G-15 deliveries commenced in 1856
RR ;-)
robin
Obviously to a design by Charles Babbage!
Red Rooster
wrote:
>Babbage
Ahhh, that's explains it! ;-)
RR
ttw...@att.net
point number for negative zero isn't a very good idea. Multiplying
-0.0 by 2 yields -0.0 whereas multiplyinb -x by 2.0 (for a very small
x) yields a smaller floating point number (bigger in magnetude).
glen herrmannsfeldt
If this is a reply to one of my posts, I wasn't suggesting using
the smallest magnitude floating point value for negative zero,
but for the mathematical lim x-->0-.
The newer Fortran standards seem to use the floating point
negative zero, for implementations that have one and can distinguish
it, for the mathematical limit.
-- glen
John W Kennedy
That is my understanding. It is tied up with the choice to regard
infinity as signed or signless.
I remember back in the 60s there was an alternate version of the
FORTRAN IV runtime for the S/360 that used negative zero for
datum-missing. Unlike modern NaN, neither the compiler nor the hardware
implemented it computationally, so you had to guard it with IFs all
over the place.
robin
Another lot of arrogant and erroneous replies from Metz,
demonstrating his ignorance of computer operations.
Robin wrote:
| >Forming the twos complement in a serial machine
| >does not require "going through the adder".
|
| It requires adding one to the low order bit and propagating the carry.
That's just the point. It doesn't "require" that at all.
Forming the ones complement and adding 1 is how you might
picture it, but hardware is not constrained by that simpleton approach.
| The easiest way to do that is to feed it through the adder. Admittedly
| you could build a special complementing unit that combined flipping
| the bits with propagating the carry, but that would add to the cost of
| the machine.
The easiest way to do that is not through the adder.
Early computers were hard-wired. In some machines, the adder
was hard-wired to one particular register. Having to form the
complement Metz's way would have destroyed the content of that register.
The twos complement can be formed trivially in other ways,
all of which avoid trashing the contents of another register.
As I laboriously explained before:
In a serial machine, the bits of a word emerge one-at-a-time,
commencing with the least-significant bit.
To form the twos complement in a serial machine,
it requires one and only one inverter and a bi-stable flip-flop.
Initially the bi-stable flip is off. When it is off, the inverter is off.
The bits are examined one-at-a-time. Immediately after a non-zero bit
has been entirely processed, the flip-flop is turned on.
When it is on, the inverter is operative,
and thus negates every subsequent bit in the word.
Thus is formed the twos complement.
Incidentally to form the ones complement of a word in such a machine,
only the inverter is required.
The cost of a forming the twos complement was a trigger and inverter,
about three valves and a handful of resistors, total cost about 6 dollars --
neither here nor there in a machine costing about $100,000.
To form the twos complement Metz' way would have required
a source of 1, components to activate the adder, etc, etc.
Next he'll be telling us that it's necessary to use the adder to subtract 1.
robin
| In <4ca9ad3f$0$33792$c30e...@exi-reader.telstra.net>, on 10/04/2010
| at 08:20 PM, David Frank <rob...@dodo.com.au> said:
|
| >Another lot of arrogant and erroneous replies
|
|
| >That's just the point. It doesn't "require" that at all.
|
I can read, and you're wrong again.
| >Initially the bi-stable flip is off. When it is off, the inverter
| >is off. The bits are examined one-at-a-time. Immediately after a
| >non-zero bit has been entirely processed, the flip-flop is turned
| >on. When it is on, the inverter is operative,
| >and thus negates every subsequent bit in the word.
|
| ROTF,LMAO!
More arrogant replies.
| >Thus is formed the twos complement.
|
| Had you not omitted a crucial step,
No step was omitted.
| what you described would have been
| an adder. As it is, it was just wrong.
Not only don't you understand plain English,
you don't understand even the basics of computer arithmetic.
Taking the bits one-at-a-time, starting from the least-significant end,
let's negate the 8-bit word 11001000
which is written 00010011 (in reverse for convenience).
Performing the above algorithm, we get (l.s. bit on left):
0
00
000
0001 (the 1-bit is unchanged)
00011 (the 0-bit is changed to 1)
000111 (do.)
0001110 (the 1-bit is changed to 0)
00011100 (do.)
Writing the bits in normal order, we have
00111000 (l.s. bit on right)
which is the twos complement of 11001000.
| >To form the twos complement Metz' way
|
| What youy describe is your way, since it doesn't come from what I
| wrote.
The way to which I referred as "your way" was the "solution"
you prooosed, namely, to use the adder. That's what you wrote.
John Rausch
computers. I did not have add hardware, but used a table in low
memory! The CEs called it the cadet (Can't Add, Doesn't Even Try).
Gordon Sande
Agreat way to do octal arithmetic as well. I believe that later models
in fact had a hardware adder.
Terence
Yup! I installed a few for IBM in the UK. Leister Tech and Lloyd's
register of shipping come to mind. Table add/substarct routine; repeat
call to this for multiply (No, not just a stupid loop, but the school
way); divide was an even longer school method. Don't ask about sqaure
roots!
robin
| In <4caa77ec$0$33795$c30e...@exi-reader.telstra.net>, on 10/05/2010
| at 11:56 AM, "robin" <rob...@dodo.com.au> said:
|
| >More arrogant replies.
|
| PKB.
More arrogant replues.
| >No step was omitted.
|
| Really? The flip-flop is supposed to stay on once you set it? In what
| universe?
What don't you understand about a flip-flop?
I described what it did, twice.
| >you don't understand even the basics of computer arithmetic.
|
| I don't have to run faster than the bear, I just have to run faster
| than you.
As I said, you (still) don't understand the basics of computer arithmetic.
1. You don't undertand a flip-flop;
2. You can't tell the difrference beqween an adder and a complementer.
| >The way to which I referred as "your way" was the "solution"
|
| No, David. It was not what I wrote, but what *you* wrote,
You've got yourself back-to-front. It was YOU
who said that
"It requires adding one to the low order bit and propagating the carry."
| and it was dishonest to attribute it to me.
Now you're lying. It was YOU who said that "It requires".
(which was your false statement, because it didn't "require" that at all.)
John W Kennedy
Yes, the 1620-1 had both addition and multiplication tables, but the
1620-2 needed only the latter.
nm...@cam.ac.uk
robin <rob...@dodo.com.au> wrote:
>
>What don't you understand about a flip-flop?
>I described what it did, twice.
Which clearly restored the initial state!
Regards,
Nick Maclaren.
robin
James Van Buskirk
news:4cac525f$0$33797$c30e...@exi-reader.telstra.net...
> ?????
T flip-flop.
--
write(*,*) transfer((/17.392111325966148d0,6.5794487871554595D-85, &
6.0134700243160014d-154/),(/'x'/)); end
robin
| "robin" <rob...@dodo.com.au> wrote in message
| news:4cac525f$0$33797$c30e...@exi-reader.telstra.net...
| > <nm...@cam.ac.uk> wrote in message
| > news:i8h8ul$3r4$1...@gosset.csi.cam.ac.uk...
| > | In article <4cabb1f6$0$33795$c30e...@exi-reader.telstra.net>,
| > | robin <rob...@dodo.com.au> wrote:
| > | >
| > | >What don't you understand about a flip-flop?
| > | >I described what it did, twice.
| > |
| > | Which clearly restored the initial state!
|
| > ?????
|
| T flip-flop.
?????
robin
| In <4cabb1f6$0$33795$c30e...@exi-reader.telstra.net>, on 10/06/2010| Nothing.
That's patently obviously a false statement.
| >I described what it did, twice.
And you still don't understand it.
nm...@cam.ac.uk
Actually, it's demonstrably YOU who still doesn't understand it :-)
Regards,
Nick Maclaren.
robin
Actually, it's you who doesn't understand it.
I correctly described it..
Bill Klein
>>Initially the bi-stable flip is off. When it is off, the inverter
>>is off. The bits are examined one-at-a-time. Immediately after a
>>non-zero bit has been entirely processed, the flip-flop is turned
>>on. When it is on, the inverter is operative,
>>and thus negates every subsequent bit in the word.
>
>
>>Thus is formed the twos complement.
>
> an adder. As it is, it was just wrong.
>
Shmuel,
This is the beginning of the "flip-flopt" discusison. As someone who:
A) doesn't know/understand "flip-flop" and "adders"
and
B) assumes that when Robin starts calling names and doesn't actually respond
to the content in notes, that he may wll be wrong (but will NEVER admit it)
Can you tell me directly WHAT step was missed in the roginal statemnent? In
other wrd, can you repeat Robin's original description and explicitly add
what was missing, so I can can see/understand it?
robin
| Shmuel,
| This is the beginning of the "flip-flopt" discusison. As someone who:
| A) doesn't know/understand "flip-flop" and "adders"
| and
| B) assumes that when Robin starts calling names and doesn't actually respond
| to the content in notes, that he may wll be wrong (but will NEVER admit it)
If you think that you are going to come back here and start
another campaign of abuse and lying, you'd better think again.
Just go away.
| Can you tell me directly WHAT step was missed in the roginal statemnent?
There was nothing missing.
| In other wrd, can you repeat Robin's original description and explicitly add
| what was missing, so I can can see/understand it?
As I said, there was nothing missing.
Metz doesn't understand how to form a complement
using the alternative algorithm.
He also couldn't tell the difference between a complementer
and an adder.
That's all there is to it.
Bill Klein
> If you think that you are going to come back here and start
> another campaign of abuse and lying, you'd better think again.
> Just go away.
>
Please point to a single post that I have ever made in this group that was a
lie. I know of one mis-use of a term that I admitted was an error; the use
of "stand-alone" when I meant "unbundled" (and even there, I don't know of
any reader who was confused by the term)
I would be HAPPY to point out many times in the past that you have made
erroneous statements and NEVER admitted your error (minor, major, technical,
or otherwise).
I would also be happy to point out the substantive note from Shmuel in the
recent thread that you did NOT answer the substance but started calling
names.
Please note that I changed the subject in my pas note and in this note. If
you would kindly reply to notes using their current subjects so that those
wishing to follow technical information/discussions in this forum without
needing to follow off-topic discussions, could do so.
Please note, I am certain that if you queried the active and less visible
participants in this forum, your technical knowledge and expertise would be
commonly acknolwedged. HOWEVER, if you also queried the viewers and
participants in the forum, I think that you would find a majority (a VERY
LARGE majority) that would confirm that you have a "online personality" that
seems totally incapable of accepting correction, criticism, or even
suggestions of other views.
My note that prompted your reply was a specific question to another
participant to explain his post. I hope he will do so. Your response, as
always, was neither responsive nor helpful.
Terence
wrote:
> <much snippage>>>Initially the bi-stable flip is off. When it is off, the inverter
> >>is off. The bits are examined one-at-a-time. Immediately after a
> >>non-zero bit has been entirely processed, the flip-flop is turned
> >>on. When it is on, the inverter is operative,
> >>and thus negates every subsequent bit in the word.
>
> >>Thus is formed the twos complement.
>
address part which is treated by Google as a bodily function measure
(!!). I actually got a rejection slip!
Trying again
Flip-flops?
What a fuss about who said what!
Actually, at Blackburn Aircraft in 1951, we were trying to build a
computer to find why aircraft tails sometimes fell off. We needed to
vibrate a bomber tail and measure at least 50 wheatstone bridge
strain-
responsive elements (strain gauges) mounted on the tail.
So we built a computer based on DC amplifiers, with twin-triode flip-
flop 1-bit storage memories, nixie-tube digital readouts and a jazzed-
up-to-10cps teleprinter i/o.
Note: the UK had the same problem again (see "Highway in the sky"):
cold metal fatigue.
But any book on elementary electronics will show the diffeernt forms
of flip-flop logic gates. We had the logic (a-la-Babbage) long before
we had the actual hardware.
John W Kennedy
> Note: the UK had the same problem again (see "Highway in the sky"):
> cold metal fatigue.
That's "No Highway in the Sky", I fancy. But that was 1951, and the
original novel ("No Highway") was 1948. Popular wisdom has it that the
inspiration was the Comet 1 failures, but they didn't happen until 1954.
(In the original book, the metal fatigue problem is apparently
predicted by quantum crystalography. Computers capable of the necessary
computations were decades away, of course.)
robin
| "robin" <rob...@dodo.com.au> wrote in message
| news:4caef640$0$33794$c30e...@exi-reader.telstra.net...
|
| > If you think that you are going to come back here and start
| > another campaign of abuse and lying, you'd better think again.
| > Just go away.
| I would also be happy to point out the substantive note from Shmuel in the
| recent thread that you did NOT answer the substance but started calling
| names.
You mean the one in which he used abusive and derogatory marks?
I think that you will find that Metz used abusive names and expressions
long before that post.
Look more carefully before you make erroneous claims.
robin
| "robin" <rob...@dodo.com.au> wrote in message
| news:4caef640$0$33794$c30e...@exi-reader.telstra.net...
|
| > If you think that you are going to come back here and start
| > another campaign of abuse and lying, you'd better think again.
| > Just go away.
|
| Please point to a single post that I have ever made in this group that was a
| lie. I know of one mis-use of a term that I admitted was an error; the use
| of "stand-alone" when I meant "unbundled" (and even there, I don't know of
| any reader who was confused by the term)
You have a conveniently short memory. Let me refresh it for you. :--
------start of post---30/11/2009----------
"William M. Klein" <wmk...@nospam.netcom.com> wrote in message
news:JFnQm.269450$sz1.2...@en-nntp-10.dc1.easynews.com...
| As usual, Robin replies by "snipping"supporting ifnormation. In this case,
| he has snipped the two online references given in the original note, i.e.:
Before replying to your post, I downl;oaded the most recent
posting of the FAQ (7 November) in this newsgroup.
As I reported, it has no reference to Micro Focus at all.
That post has been in the FAQ archives snce October.
That's what proves you to be a liar.
The post that you reference at:
| http://www.faqs.org/faqs/computer-lang/pli-faq/
is obsolete, and is dated November 2008. That's ONE YEAR AGO.
But that makes you still a liar, and a clown to boot.
--------end of post----------
Bill Klein
post was against a version taht was posted to the comp.lang.pl1 newsgtroup.
As you (eventually) admitted, the psted version was NOT the current version.
The one that I pointed out the problem in was the one that was posted and to
which I recplied.
Notice that even you stated, that I referered to:
"> The post that you reference at:
>
> | http://www.faqs.org/faqs/computer-lang/pli-faq/
>
> is obsolete, and is dated November 2008. That's ONE YEAR AGO."
To avoid "snippage" problems, the following was my complete post of
11-29-2009, 04:30 AM
"
As usual, Robin replies by "snipping"supporting ifnormation. In this case,
he has snipped the two online references given in the original note, i.e.:
http://www.faqs.org/faqs/computer-lang/pli-faq/
and
http://home.roadrunner.com/~pflass/m..._v/pli_faq.htm
See the text,
"Microfocus Open PL/I, for Intel running Windows XP, 2000, Me/98. Comes
with ..."
Those web sites SEEM to "have yoru blessings". Are you now dis-avoig them?
* * * *
The post from YOU date/time stamped
Friday, November 06, 2009 11:17 PM
to this newsgroups includes the following text,
"MicroFocus offers tools to accompany PL/I for OS/2 ..."
* * * * *
Others may find it "amusing" that rather than admit you were wrong and FIX
the name of the company and copiler, you have now removed references to
"Open PL/I". If you want curent information on this "Micro Focus" (not
"MicroFocus") product, check out
http://www.microfocus.com/products/OpenPLI/index.asp
The FAQ seems to think that Liant still exists."
* * * *
The post of Robin's that I was responded to wast the "Nov 7 2009, 12:17 am"
post to comp.lang.pl1 which starts,
"Archive-name: computer-lang/pli-faq
Last-Modified: 28 October 2009
Version: 1.7
FREQUENTLY-ASKED QUESTIONS & ANSWERS "
You can see the full past at (long URL):
Within that document (and why I posted what I said) was the following (that
nyone can find even today),
"
Liant Open PL/I, for Intel running Windows XP, 2000, Me/98.
Comes with Codewatch, Liant's powerful GUI source code debugger.
---available from Liant Software Corporation,
8911 N Capital of Texas Hwy 354 Waverley Street
Austin, Texas 78759-7267 Framingham, MA 01702
USA USA
Toll free: 1-800-349-9222
Tel: (512) 343-1010 (508) 416-1614 Direct
Fax: (512) 343-9487 or
Tel: (800) 818-4754 X1614 (USA Only)
Fax: (508) 278-3841
(their PL/I generally is available on Unix-based systems)
See http://www.liant.com/products/pl1
for a full range of PL/I products.
also in that post was
"MicroFocus offers tools to accompany PL/I for OS/2. For more infomation,
contact them at Suite 400, 2465 East Bayshore Road, Palo Alto, CA 94303,
U.S.A.
Visit: http://www.mfltd.co.uk/ "
I did admit that my original reference to "Microfocus" rather than
"MicroFocus" was in error, but the orirignal point was that the trademarked
name includes a space. (I don't remember now if Robin actually ever
admitted that "Micro Focus" was a trademarked name - at least in the US.
However, that was confirmed to the group from Micro Focus itself).
* * * * *
So as asked then and as you bring it up now.
When did I lie and what was my lie?
I replied to a positng to cmp.lang.pl1 with an ERROR (Liant rather than
Micro Focus) and a incorrect name ("MicroFocus" rather than "Micro Focus").
Even now, if you can find any error (much less lie) in my reflections on
your post of Nov 7, 2009 (not 2008), please point me to it. I am always
willing to admit when I make an error (such as "Microfocus" vs
"MicroFocus"). Something that you seem incapable of.l
.
IBM AS/400
--- available from IBM.
.
IBM mainframes
--- The followng versions are available from IBM:
IBM Enterprise PL/I for z/OS and OS/390
provides access to DB2, CICS, IMS, and other data and
transactions systems.
.
"robin" <rob...@dodo.com.au> wrote in message
news:4cafb7ab$0$33790$c30e...@exi-reader.telstra.net...
Peter Flass
> If you actually looked at the full thread, you would see that my original
> post was against a version taht was posted to the comp.lang.pl1 newsgtroup.
>
Call the playground monitor -- the children are squabbling in the
sandbox again.
robin
| In <KJkro.239970$MG3....@en-nntp-16.dc1.easynews.com>, on 10/07/2010
| at 09:23 AM, "Bill Klein" <wmk...@noreply.ix.netcom.com> said:
|
| >Can you tell me directly WHAT step was missed in the roginal
| >statemnent? In other wrd, can you repeat Robin's original
| >description and explicitly add what was missing, so I can can
| >see/understand it?
|
Because you know that your silly assertion won't stand up to public scrutiny.
You might fool Klein, who confessed that
he doesn't understand it, but you don't fool anyone else.
John W Kennedy
> In <4cb0562b$0$33796$c30e...@exi-reader.telstra.net>, on 10/09/2010
> at 01:23 PM, "robin" <rob...@dodo.com.au> said:
>
>> Because you know that your silly assertion won't stand up to public
>> scrutiny.
>
> Wrong again. I sent it offline because I prefer that you dig yourself
> in deeper. I believe that some other readers have already noticed what
> you got wrong.
You know, all this commenting on comments is beginning to get rather
diffuse. As far as I can see, unless you are making some very obscure
quibble, RV's description of how a little-endian serial-by-bit device
can generate a 2's complement (which /seems/ to be what you're talking
about) is quite correct.
I have no idea, of course, whether he is correctly describing period
hardware as it was actually built; coming from the world of IBM as I
do, I know serial-by-bit only as a sort of myth as antipodean as it is
antediluvian.
robin
| "robin" <rob...@dodo.com.au> wrote in message
| news:4caef640$0$33794$c30e...@exi-reader.telstra.net...
|
| > If you think that you are going to come back here and start
| > another campaign of abuse and lying, you'd better think again.
| > Just go away.
You have obviously come here to make trouble.
In your post there were five* paragraphs,
and in each paragraph was a derogatory remark.
See them below.
| I would be HAPPY to point out many times in the past that you have made
| erroneous statements and NEVER admitted your error (minor, major, technical,
| or otherwise).
|
| I would also be happy to point out the substantive note from Shmuel in the
| recent thread that you did NOT answer the substance but started calling
| names.
|
| Please note that I changed the subject in my pas note and in this note. If
| you would kindly reply to notes using their current subjects so that those
| wishing to follow technical information/discussions in this forum without
| needing to follow off-topic discussions, could do so.
|
| Please note, I am certain that if you queried the active and less visible
| participants in this forum, your technical knowledge and expertise would be
| commonly acknolwedged. HOWEVER, if you also queried the viewers and
| participants in the forum, I think that you would find a majority (a VERY
| LARGE majority) that would confirm that you have a "online personality" that
| seems totally incapable of accepting correction, criticism, or even
| suggestions of other views.
|
| My note that prompted your reply was a specific question to another
| participant to explain his post. I hope he will do so. Your response, as
| always, was neither responsive nor helpful.
____________
*not including one in which you said that you had not lied,
which was a false statement.
robin
| If you actually looked at the full thread, you would see that my original
| post was against a version taht was posted to the comp.lang.pl1 newsgtroup.
|
| As you (eventually) admitted, the psted version was NOT the current version.
Don't be ridiculous.
The posted version was the current one.
It was posted on 7 November 2009, and had been
in the FAQ archive since October.
The one to which you refered was November 2008,
which was ONE YEAR earlier.
This was stated in my posting of 30/11/2009 herewith:
robin
| In <4cc596b2$0$496$c30e...@exi-reader.telstra.net>, on 10/25/2010
| at 10:26 PM, David Frank" <rob...@dodo.com.au> said:
|
| >So that it won't be exposed to public scrutiny.
|
| ROTF,LMAO! Were that the case I wouldn't offer to explain it to
| anybody but you, David. Not that you are capable of understanding
| explanations.
No-one's even slightly amused at your infantile remarks.
The fact is, you don't understand complement.
Bill Klein
thread. He is correct the FAQ was posted on Nov 7, 2009. and reflected the
FAQ of Oct 2009.
HOWEVER, it is that FAQ which included
- references to Liant
- the spelling "Microfocus"
Both were wrong.
Again, (as seen in this and many other threads) Robin Vowel seems incapable
of admitting an error.
I do wonder whether his problem is that he claims that I lie. I have made
errors in this (and other forums) in the past and when they were pointed out
to me, I admitted my errors. (This was case of the "bad" Nov 2009 FAQ was
NOT such a case).
However, RV (as far as I can tell) may consider these "lies". Maybe this is
his basic problem, he doesn't understand the difference between lies and
errors. Therefore, he is afraid to admit his "errors" as he thinks that
doing so would be to admit to "lying"
I don't know; this is just a guess. I stand by all the factual statements in
the attached/following note and will be willing to provide online references
to substantiate them
"robin" <rob...@dodo.com.au> wrote in message
news:4cc596ae$0$496$c30e...@exi-reader.telstra.net...
Shmuel Metz
at 10:26 PM, David Frank" <rob...@dodo.com.au> said:
>So that it won't be exposed to public scrutiny.
ROTF,LMAO! Were that the case I wouldn't offer to explain it to
anybody but you, David. Not that you are capable of understanding
explanations.
--
Shmuel (Seymour J.) Metz, SysProg and JOAT <http://patriot.net/~shmuel>
Unsolicited bulk E-mail subject to legal action. I reserve the
right to publicly post or ridicule any abusive E-mail. Reply to
domain Patriot dot net user shmuel+news to contact me. Do not
reply to spam...@library.lspace.org
Shmuel Metz
at 10:43 PM, "robin" <rob...@dodo.com.au> said:
>The fact is, you don't understand complement.
ROTF,LMAO! The fact is that you don't understand sequential logic.