Prev: Omega Constellation Mens Watch 1512.30
Next: Of Wacom tablets, terminals, serial ports, and adapters
From: Geoffrey S. Mendelson on 27 Apr 2010 16:19
The Translucent Amoebae wrote:
> The definitive Sort routine.

I don't think that one will ever really be known. The first US software
patent (maybe the first worldwide) was for a sort program. It was sold
as SyncSort for the IBM mainframe. I don't know where the IBM team was,
but I met the SyncSort team and they were in the Philly area, possibly
Princeton.

For many years there was a contest between IBM's sort/merge, the free sort
included in the free operating systems, and SyncSort. Each one had its
advantages and disadvantages.

While you could with some accuracy predict which sort would perform better
(insert your definition of better) for a given set of data, none was the
absolute best for a all sets of data in any order, with any number and order
of keys.

Better could be defined as fastest (clock time), fastest (CPU time),
core (memory before it was called RAM) usage, temporary file useage,
IO operations, etc.

There were also complicating factors, if the input or output was a tape
device, you wanted the data to flow fast enough that it did not stop. Every
time a tape device was unable to send data to the computer or received another
block to write, it stopped, which slowed it down enourmously.

As for their being a definitive sort routine, there is the famous
"bubble sort", which is used in computer science classes, and many
free implementations, but the real heavy duty sort algorythms are
still probably trade secrets, kept well hidden.

Geoff.
--
Geoffrey S. Mendelson, Jerusalem, Israel gsm(a)mendelson.com N3OWJ/4X1GM
New word I coined 12/13/09, "Sub-Wikipedia" adj, describing knowledge or
understanding, as in he has a sub-wikipedia understanding of the situation.
i.e possessing less facts or information than can be found in the Wikipedia.
From: Matthew Russotto on 28 Apr 2010 00:01
In article <tph-2F6DCD.16472326042010(a)localhost>,
Tom Harrington <tph(a)pcisys.no.spam.dammit.net> wrote:
>In article <hr4tjv$6e3$1(a)news.eternal-september.org>,
> Phillip Jones <pjones1(a)kimbanet.com> wrote:
>
>> I don't know whether it it is still in the Principal's Office. But when
>> I worked for a school system there was a very tall wall Clock that used
>> a Paper Tape It was functioning at the time as Clock. I think it at one
>> time run the bells. But it was an endless lop punched paper tape about
>> 6 inches wide.
>
>Sounds like a prime target for student pranks.

I'd be tempted to cut it and re-form it as a mobius strip. Then every
other day the bells would be absolutely screwy :-)

--
The problem with socialism is there's always
someone with less ability and more need.
From: TaliesinSoft on 28 Apr 2010 00:21
On 2010-04-24 17:52:50 -0500, The Translucent Amoebae said:

> i was then wondering - Who are the best programmers...?
> In the early days of programming, many very hard & counter-intuitive
> problems were solved by some very clever programmers and programming
> routines, routines which are now ubiquitous in nearly all
> applications.

One who stands out to me is Kenneth Iverson, the person who laid out
the fundamentals upon which the programming language APL (A Programming
Language) was developed. I am not aware of any other programming
language in which one could do such as, using only the primitive
functions of the language and not any defined routines, take the
average of an arbitrary collection of numbers, regardless of how many
numbers were in the collection, in just eight characters. A computer
scientist at a university in London went on record as saying that when
comparing a common solution in APL with the same solution in Fortran
that the APL solution took one tenth the amount of code. I say this as
a person that became a personal friend of Iverson and as a person that
headed the implementation of two different APL interpreters for two
different computer manufacturers.

--
James Leo Ryan --- Austin, Texas --- taliesinsoft(a)me.com

From: Tom Harrington on 28 Apr 2010 00:35
In article <83pre6FfiuU1(a)mid.individual.net>,
TaliesinSoft <taliesinsoft(a)me.com> wrote:

> On 2010-04-24 17:52:50 -0500, The Translucent Amoebae said:
>
> > i was then wondering - Who are the best programmers...?
> > In the early days of programming, many very hard & counter-intuitive
> > problems were solved by some very clever programmers and programming
> > routines, routines which are now ubiquitous in nearly all
> > applications.
>
> One who stands out to me is Kenneth Iverson, the person who laid out
> the fundamentals upon which the programming language APL (A Programming
> Language) was developed. I am not aware of any other programming
> language in which one could do such as, using only the primitive
> functions of the language and not any defined routines, take the
> average of an arbitrary collection of numbers, regardless of how many
> numbers were in the collection, in just eight characters. A computer
> scientist at a university in London went on record as saying that when
> comparing a common solution in APL with the same solution in Fortran
> that the APL solution took one tenth the amount of code. I say this as
> a person that became a personal friend of Iverson and as a person that
> headed the implementation of two different APL interpreters for two
> different computer manufacturers.

When I was in college they still had APL-compatible keyboards on the
terminals. Which, it seemed to me, was the problem, that it required
special hardware just to write it. In my brief exposure to it I found
that while it might use 1/10 as much code as other languages for the
same operations, it was also only 1/10 as comprehensible. I found Perl
to be easier to read, and I've written some pretty hairy Perl. APL was
elegant and powerful, but it seemed to require geniuses with a good
hardware budget to make use of it.

--
Tom "Tom" Harrington
Independent Mac OS X developer since 2002
http://www.atomicbird.com/
From: TaliesinSoft on 28 Apr 2010 00:59
On 2010-04-27 23:35:54 -0500, Tom Harrington said:

[in regards to APL]

> When I was in college they still had APL-compatible keyboards on the
> terminals. Which, it seemed to me, was the problem, that it required
> special hardware just to write it. In my brief exposure to it I found
> that while it might use 1/10 as much code as other languages for the
> same operations, it was also only 1/10 as comprehensible. I found Perl
> to be easier to read, and I've written some pretty hairy Perl. APL was
> elegant and powerful, but it seemed to require geniuses with a good
> hardware budget to make use of it.

There was a time when APL was literally programmable from an IBM
Selectric terminal with an APL type ball. I was one who readily learned
to touch type APL and didn't need an APL keyboard. Later, when CRT
terminals became available, it was common that a terminal could display
both ASCII and APL without a problem.

As for APL being "1/10 as comprehensible" I have difficulty in fully
understanding that as I have never experienced a problemin
understanding the details of a program written in APL. And, of course,
a bit of commenting helps!






--
James Leo Ryan --- Austin, Texas --- taliesinsoft(a)me.com

First  |  Prev  |  Next  |  Last
Pages: 1 2 3 4 5
Prev: Omega Constellation Mens Watch 1512.30
Next: Of Wacom tablets, terminals, serial ports, and adapters