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OT: Elevator Algorithm

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Jim Thompson

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Sep 7, 2006, 8:17:14 PM9/7/06
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Having spent the last two days attending meetings in a high-rise, I
was musing...

What algorithm is used to ensure that the elevator door that you are
standing in front of WILL NOT BE the one that opens ?:-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Stephen J. Rush

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Sep 7, 2006, 8:28:36 PM9/7/06
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On Thu, 07 Sep 2006 17:17:14 -0700, Jim Thompson wrote:

> Having spent the last two days attending meetings in a high-rise, I
> was musing...
>
> What algorithm is used to ensure that the elevator door that you are
> standing in front of WILL NOT BE the one that opens ?:-)

An algorithm? I thought is was a reflection of the natural law that makes
the probability of encountering a cop (or a prostitute, or a car salesman)
an inverse function of your desire for one.

James Thompson

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Sep 7, 2006, 8:47:43 PM9/7/06
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"Jim Thompson" <To-Email-Use-Th...@My-Web-Site.com> wrote in
message news:ued1g29jq2au7u2ml...@4ax.com...

> Having spent the last two days attending meetings in a high-rise, I
> was musing...
>
> What algorithm is used to ensure that the elevator door that you are
> standing in front of WILL NOT BE the one that opens ?:-)
>
> ...Jim Thompson
Its a sensor they use that tell's the elevator to only stop on empty floors.
:)


John Woodgate

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Sep 8, 2006, 1:38:29 AM9/8/06
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In message <e00b9$4500bd6e$471cd528$23...@ALLTEL.NET>, dated Thu, 7 Sep
2006, James Thompson <Jamestho...@hotmail.com> writes
What do you dial to get the apostrophe police? Is it 9'1'1'?
--
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
There are benefits from being irrational - just ask the square root of 2.
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

John Woodgate

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Sep 8, 2006, 1:37:02 AM9/8/06
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In message <ued1g29jq2au7u2ml...@4ax.com>, dated Thu, 7
Sep 2006, Jim Thompson <To-Email-Use-Th...@My-Web-Site.com>
writes

>What algorithm is used to ensure that the elevator door that you are
>standing in front of WILL NOT BE the one that opens ?:-)

Murphymorphic resonance. Just like in the 'three doors' problem, you can
improve your chances of success by switching to another door after
waiting 20 seconds. (;-)

to...@fullnet.com

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Sep 8, 2006, 2:15:17 AM9/8/06
to

It's an adaptive algorithm that depends on the algorithm YOU use to
select which door to stand near. The better your algorithm is, the
better the elevators are at opening a door you're not standing near.
But think of all the algorithmically-challenged people who stood near
the "wrong" elevators, whom you helped.

- Tom Gootee

"He who lives in a glass house should not invite he who is without
sin."

Michael A. Terrell

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Sep 8, 2006, 2:35:07 AM9/8/06
to
to...@fullnet.com wrote:
>
> It's an adaptive algorithm that depends on the algorithm YOU use to
> select which door to stand near. The better your algorithm is, the
> better the elevators are at opening a door you're not standing near.
> But think of all the algorithmically-challenged people who stood near
> the "wrong" elevators, whom you helped.


How about when you walk up to a bank of four elevators just as they
all open at the same time? It was really weird. Of course it was a
government building.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Clifford Heath

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Sep 8, 2006, 3:19:20 AM9/8/06
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Michael A. Terrell wrote:
> How about when you walk up to a bank of four elevators just as they
> all open at the same time?

That only happens if you stand *exactly* in the center equidistant from
all four. The system cannot inconvenience you, so it tries to confuse you.

Frithiof Andreas Jensen

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Sep 8, 2006, 4:07:36 AM9/8/06
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"Michael A. Terrell" <mike.t...@earthlink.net> wrote in message
news:45010F0A...@earthlink.net...

> to...@fullnet.com wrote:
> >
> > It's an adaptive algorithm that depends on the algorithm YOU use
to
> > select which door to stand near. The better your algorithm is,
the
> > better the elevators are at opening a door you're not standing
near.
> > But think of all the algorithmically-challenged people who stood
near
> > the "wrong" elevators, whom you helped.
>
>
> How about when you walk up to a bank of four elevators just as
they
> all open at the same time? It was really weird. Of course it was a
> government building.

Hmmm.

The elevators are cursed and one of the three will take you directly
to the sub-sub-sub-basement furnace as part of the pact that
Government made in return for power without reckoning ;-)


to...@fullnet.com

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Sep 8, 2006, 4:45:29 AM9/8/06
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Obviously the elevator system must have thought that you either didn't
care or weren't going to use an elevator. :-)

- Tom Gootee

Mark Fortune

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Sep 8, 2006, 5:10:00 AM9/8/06
to

And then the one you move towards closes.

Michael A. Terrell

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Sep 8, 2006, 12:54:51 PM9/8/06
to
to...@fullnet.com wrote:
>
> Obviously the elevator system must have thought that you either didn't
> care or weren't going to use an elevator. :-)


It was at the VA hospital in Gainsville. The only reason to be where
I was, was to use an elevator. They were in a small bay off the main
hallway. ;)

Michael A. Terrell

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Sep 8, 2006, 12:56:09 PM9/8/06
to
Frithiof Andreas Jensen wrote:
>
> Hmmm.
>
> The elevators are cursed and one of the three will take you directly
> to the sub-sub-sub-basement furnace as part of the pact that
> Government made in return for power without reckoning ;-)


I was already at the lowest level in the building, just around the
corner from the canteen. ;)

Michael A. Terrell

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Sep 8, 2006, 12:57:33 PM9/8/06
to

No, they are all set for the handicapped, so most of the time people
end up pushing the "Close Door" button to reduce the wait time if no one
is coming.

Michael A. Terrell

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Sep 8, 2006, 1:04:50 PM9/8/06
to


Nice try, but they opened just as I came around the corner, into the
elevator bay at the hospital. It reminded me of making the hour long
drive home from work one night and having all 27 traffic lights green,
when I rarely saw more than five green lights. That happened only the
one time in my four years of working for UVCI on night shift in
Cincinnati, Ohio.

Joerg

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Sep 8, 2006, 1:42:36 PM9/8/06
to
Hello Jim,


> Having spent the last two days attending meetings in a high-rise, I
> was musing...
>
> What algorithm is used to ensure that the elevator door that you are
> standing in front of WILL NOT BE the one that opens ?:-)
>

That would be the Murphy algorithm.

--
Regards, Joerg

http://www.analogconsultants.com

o...@uakron.edu

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Sep 8, 2006, 1:51:03 PM9/8/06
to
all three of ours would only come to one floor for a fire alarm.
dont get me started on the "fuzzy logic" controller, or how in a 13
story building, if your downbound, its often faster to get on the
upbound one and wait for it to reverse, then to wait for the car you
pushed for. Of course it will then stop first at the floor you got on
at.

Steve Roberts

Oppie

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Sep 8, 2006, 1:52:00 PM9/8/06
to

"Jim Thompson" <To-Email-Use-Th...@My-Web-Site.com> wrote in
message news:ued1g29jq2au7u2ml...@4ax.com...
> Having spent the last two days attending meetings in a high-rise, I
> was musing...
>
> What algorithm is used to ensure that the elevator door that you are
> standing in front of WILL NOT BE the one that opens ?:-)
>
> ...Jim Thompson

you missed you chance to try this one out for making the elevator non-stop
http://www.eeggs.com/items/12697.html

Oppie


Nico Coesel

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Sep 8, 2006, 3:04:29 PM9/8/06
to
Jim Thompson <To-Email-Use-Th...@My-Web-Site.com> wrote:

>Having spent the last two days attending meetings in a high-rise, I
>was musing...
>
>What algorithm is used to ensure that the elevator door that you are
>standing in front of WILL NOT BE the one that opens ?:-)

Can we stop this topic? Someone with a sadistic mind already invented
that and implemented it in a hospital. As a bonus that person made the
doors close very soon after they opened. I had to use a plant to stop
the doors so I could push my grandfather + wheelchair into the
elevator.

--
Reply to nico@nctdevpuntnl (punt=.)
Bedrijven en winkels vindt U op www.adresboekje.nl

Martine Riddle

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Sep 9, 2006, 7:31:52 PM9/9/06
to
"Jim Thompson" <To-Email-Use-Th...@My-Web-Site.com> wrote in
message news:ued1g29jq2au7u2ml...@4ax.com...
> Having spent the last two days attending meetings in a high-rise, I
> was musing...
>
> What algorithm is used to ensure that the elevator door that you are
> standing in front of WILL NOT BE the one that opens ?:-)
>

What floor was it, 7 1/2 ?

Cheers


Michael A. Terrell

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Sep 9, 2006, 8:18:42 PM9/9/06
to


The 13th floor.

Homer J Simpson

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Sep 9, 2006, 9:17:54 PM9/9/06
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"Martine Riddle" <marti...@verizon.net> wrote in message
news:I9IMg.81$gN1.30@trndny08...

> What floor was it, 7 1/2 ?

Isn't that the one to Hogwart's?

Tim Williams

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Sep 9, 2006, 11:15:54 PM9/9/06
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"Homer J Simpson" <nob...@nowhere.com> wrote in message
news:6JJMg.902$bf5.401@edtnps90...

>> What floor was it, 7 1/2 ?
>
> Isn't that the one to Hogwart's?

Was 7 1/2 the number in Being John Malkovich, or was that like 13 or 13 1/2?

Tim

--
Deep Fryer: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms


xray

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Sep 10, 2006, 8:24:18 AM9/10/06
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On Sat, 9 Sep 2006 22:15:54 -0500, "Tim Williams"
<tmor...@charter.net> wrote:

>"Homer J Simpson" <nob...@nowhere.com> wrote in message
>news:6JJMg.902$bf5.401@edtnps90...
>>> What floor was it, 7 1/2 ?
>>
>> Isn't that the one to Hogwart's?
>
>Was 7 1/2 the number in Being John Malkovich, or was that like 13 or 13 1/2?
>
>Tim
>

"Being John Malkovich":
Lester Corp. on the 7-1/2 floor of the Mertin Flemmer building, 610 11th
Ave. "Short statured file clerk with unusually nimble and dextrous
fingers needed for speed filing." (Use the crowbar in the elevator.)

Whoosh!


Martine Riddle

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Sep 10, 2006, 9:28:22 PM9/10/06
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"Tim Williams" <tmor...@charter.net> wrote in message
news:lMLMg.349$xn5...@newsfe05.lga...

> "Homer J Simpson" <nob...@nowhere.com> wrote in message
> news:6JJMg.902$bf5.401@edtnps90...
>>> What floor was it, 7 1/2 ?
>>
>> Isn't that the one to Hogwart's?
>
> Was 7 1/2 the number in Being John Malkovich, or was that like 13 or 13
> 1/2?
>
Yes, it was the 7 1/2 floor. John Cusak played the loser filing clerk.


Cheers


Rich Grise

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Sep 11, 2006, 8:35:55 PM9/11/06
to
On Thu, 07 Sep 2006 17:17:14 -0700, Jim Thompson wrote:

> Having spent the last two days attending meetings in a high-rise, I
> was musing...
>
> What algorithm is used to ensure that the elevator door that you are
> standing in front of WILL NOT BE the one that opens ?:-)
>
> ...Jim Thompson

Murphy's.

;-)

Cheers!
Rich


Rich Grise

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Sep 11, 2006, 8:49:02 PM9/11/06
to
On Thu, 07 Sep 2006 23:15:17 -0700, tomg wrote:
> Jim Thompson wrote:
>> Having spent the last two days attending meetings in a high-rise, I
>> was musing...
>>
>> What algorithm is used to ensure that the elevator door that you are
>> standing in front of WILL NOT BE the one that opens ?:-)
>
> It's an adaptive algorithm that depends on the algorithm YOU use to
> select which door to stand near. The better your algorithm is, the
> better the elevators are at opening a door you're not standing near.
> But think of all the algorithmically-challenged people who stood near
> the "wrong" elevators, whom you helped.
>
> "He who lives in a glass house should not invite he who is without
> sin."

I think, in this case, it's "should not invite him", since "him" is
the object of the verb "invite". "who is without sin" is still OK,
however, since it's a subordinate clause modifying "him" (the object
of the verb.)

Like, it should be "Let him cast the first stone". If you want to
be more specific about "him", it would be "who has not sinned."

Now, if you're taling about "none so blind as he who will not see",
then it's "he", since "as" is a conjunction, i.e., "none so blind
as he (who will not see) is blind."

My Mom (RIP) taught me this stuff many, many years ago, which is
why I got A's in school, until they got to the hard stuff. ;-P

Thanks,
Rich

Rich Grise, Plainclothes Hippie

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Sep 11, 2006, 8:51:05 PM9/11/06
to
On Fri, 08 Sep 2006 06:35:07 +0000, Michael A. Terrell wrote:
> to...@fullnet.com wrote:
>>
>> It's an adaptive algorithm that depends on the algorithm YOU use to
>> select which door to stand near. The better your algorithm is, the
>> better the elevators are at opening a door you're not standing near.
>> But think of all the algorithmically-challenged people who stood near
>> the "wrong" elevators, whom you helped.
>
> How about when you walk up to a bank of four elevators just as they
> all open at the same time? It was really weird. Of course it was a
> government building.


It was synchronicity, Michael. The Universe was trying to tell you
how important you are to it.


The appropriate response, of course, would have been to board all
four eleveators simultaneously.

Cheers!
Rich

Rich Grise, Plainclothes Hippie

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Sep 11, 2006, 8:57:56 PM9/11/06
to
On Fri, 08 Sep 2006 16:56:09 +0000, Michael A. Terrell wrote:
> Frithiof Andreas Jensen wrote:
>>
>> The elevators are cursed and one of the three will take you directly
>> to the sub-sub-sub-basement furnace as part of the pact that
>> Government made in return for power without reckoning ;-)
>
> I was already at the lowest level in the building, just around the
> corner from the canteen. ;)

They were already there. That's where they go on standby, when there's
no usage for awhile. That's where the firmware leaves them set, because
it's easier on the seals.

When you arrived, the individual PIR or radar or sonar sensor (that each
elevator door has one of) energized, saying to its controller, "Potential
Passenger", and each responded in kind by opening its door and offering
its services to you, since the car happened to be available on that floor.

Cheers!
Rich


Rich Grise, Plainclothes Hippie

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Sep 11, 2006, 9:06:14 PM9/11/06
to
On Fri, 08 Sep 2006 17:04:50 +0000, Michael A. Terrell wrote:
> Clifford Heath wrote:
>> Michael A. Terrell wrote:
>> > How about when you walk up to a bank of four elevators just as they
>> > all open at the same time?
>>
>> That only happens if you stand *exactly* in the center equidistant from
>> all four. The system cannot inconvenience you, so it tries to confuse you.
>
> Nice try, but they opened just as I came around the corner, into the
> elevator bay at the hospital. It reminded me of making the hour long
> drive home from work one night and having all 27 traffic lights green,
> when I rarely saw more than five green lights. That happened only the
> one time in my four years of working for UVCI on night shift in
> Cincinnati, Ohio.

OK, then, that pretty much verifies it. It was synchronicity. The
Universe is really, really trying to give you an easy path. What you
really need to do is investigate what obstacles you have been presenting
to yourself.

You might try here:
http://healingtowholeness.com/

Good Luck!
Rich

to...@fullnet.com

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Sep 12, 2006, 6:20:27 PM9/12/06
to

Rich,

Thanks for taking the time to discuss grammar. You might be correct.
However, I wanted the portions of the two original quotations to be
more-recognizable; i.e. with their familiar wording. And it might just
be correct that the entire phrase "he who is without sin" can be the
object of the verb "invite". (Also: My "ear" is pretty good, too. And
I *really* don't like the sound of "... him who is without sin".) See
revised sig, farther below.

You were lucky to have a Mom who did that for you. I did, too,
actually. I also had four older sisters whom she trained (in more
ways than just "grammarianliness"), possibly even somewhat more
rigorously than she trained me, since she was probably getting weary,
by then. In my case, then, it was often like having *five* Moms, with
the younger four moms having more energy, but maybe a bit less patience
and kindness, and, obviously but often unfortunately, greater numbers.
Let's put it this way: I learned well, and quickly, that I had better
learn well, and quickly.

I sure was glad, when my brother was born.

Cheers!

- Tom Gootee

quietguy

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Sep 12, 2006, 7:30:28 PM9/12/06
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Busting for a leak and the gents is 4 floors down will guarantee it

David

to...@fullnet.com

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Sep 13, 2006, 4:43:27 AM9/13/06
to

Oops. I meant:

"He who lives in a glass house" should not invite "he who is without
sin".

- Tom Gootee

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