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Encapsulation, inheritance and polymorphism

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  Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 09:45 +0100
    Re: Encapsulation, inheritance and polymorphism Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-07-17 06:03 -0400
      Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 12:24 +0100
        Re: Encapsulation, inheritance and polymorphism Larry Hudson <orgnut@yahoo.com> - 2012-07-18 00:10 -0700
    Re: Encapsulation, inheritance and polymorphism Ulrich Eckhardt <ulrich.eckhardt@dominolaser.com> - 2012-07-17 11:30 +0200
      Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 12:01 +0100
        Re: Encapsulation, inheritance and polymorphism Dave Angel <d@davea.name> - 2012-07-17 07:23 -0400
        Re: Encapsulation, inheritance and polymorphism Andrew Berg <bahamutzero8825@gmail.com> - 2012-07-17 06:37 -0500
          Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 12:44 +0100
            Re: Encapsulation, inheritance and polymorphism Andrew Berg <bahamutzero8825@gmail.com> - 2012-07-17 06:53 -0500
            Re: Encapsulation, inheritance and polymorphism Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-07-17 14:35 +0100
          Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 15:01 +0100
            Re: Encapsulation, inheritance and polymorphism Andrew Berg <bahamutzero8825@gmail.com> - 2012-07-17 09:16 -0500
              Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 15:26 +0100
            Re: Encapsulation, inheritance and polymorphism Terry Reedy <tjreedy@udel.edu> - 2012-07-17 13:30 -0400
            Re: Encapsulation, inheritance and polymorphism Andrew Berg <bahamutzero8825@gmail.com> - 2012-07-17 12:57 -0500
        Re: Encapsulation, inheritance and polymorphism Ulrich Eckhardt <ulrich.eckhardt@dominolaser.com> - 2012-07-17 14:18 +0200
        Re: Encapsulation, inheritance and polymorphism Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-07-17 14:29 +0100
        Re: Encapsulation, inheritance and polymorphism Roy Smith <roy@panix.com> - 2012-07-17 09:52 -0400
          Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 15:23 +0100
            Re: Encapsulation, inheritance and polymorphism Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-07-17 17:26 +0100
              Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 17:46 +0100
            Re: Encapsulation, inheritance and polymorphism Terry Reedy <tjreedy@udel.edu> - 2012-07-17 13:07 -0400
              Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 20:29 +0100
                Re: Encapsulation, inheritance and polymorphism Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-07-17 20:39 +0100
                  Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 20:52 +0100
                  Re: Encapsulation, inheritance and polymorphism John Ladasky <john_ladasky@sbcglobal.net> - 2012-08-18 23:05 -0700
                  Re: Encapsulation, inheritance and polymorphism John Ladasky <john_ladasky@sbcglobal.net> - 2012-08-18 23:05 -0700
                Re: Encapsulation, inheritance and polymorphism Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-07-17 18:57 -0400
            Re: Encapsulation, inheritance and polymorphism Ethan Furman <ethan@stoneleaf.us> - 2012-07-17 10:29 -0700
            Re: Encapsulation, inheritance and polymorphism Chris Angelico <rosuav@gmail.com> - 2012-07-18 04:01 +1000
            Re: Encapsulation, inheritance and polymorphism Tim Chase <python.list@tim.thechases.com> - 2012-07-17 12:51 -0500
            Re: Encapsulation, inheritance and polymorphism Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-07-17 19:18 +0100
              Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 19:36 +0100
                Re: Encapsulation, inheritance and polymorphism Andrew Cooper <amc96@cam.ac.uk> - 2012-07-18 01:46 +0100
                  Re: Encapsulation, inheritance and polymorphism rusi <rustompmody@gmail.com> - 2012-07-17 20:54 -0700
                  Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-18 10:06 +0100
                    Re: Encapsulation, inheritance and polymorphism Ulrich Eckhardt <ulrich.eckhardt@dominolaser.com> - 2012-07-18 14:01 +0200
                    Re: Encapsulation, inheritance and polymorphism "BartC" <bc@freeuk.com> - 2012-07-19 01:41 +0100
                  Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-18 13:05 +0000
                    Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-18 15:40 +0100
                      Re: Encapsulation, inheritance and polymorphism Chris Angelico <rosuav@gmail.com> - 2012-07-19 01:04 +1000
                        Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-19 01:22 +0000
                          Re: Encapsulation, inheritance and polymorphism Chris Angelico <rosuav@gmail.com> - 2012-07-19 15:09 +1000
                      Re: Encapsulation, inheritance and polymorphism Ethan Furman <ethan@stoneleaf.us> - 2012-07-18 08:32 -0700
                        Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-18 16:49 +0100
                      Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-19 01:34 +0000
                        Re: Encapsulation, inheritance and polymorphism rusi <rustompmody@gmail.com> - 2012-07-18 23:09 -0700
                          Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-19 09:56 +0100
                            Re: Encapsulation, inheritance and polymorphism rusi <rustompmody@gmail.com> - 2012-07-19 08:58 -0700
                          Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-19 12:59 +0000
                            Re: Encapsulation, inheritance and polymorphism Roy Smith <roy@panix.com> - 2012-07-19 09:06 -0400
                              Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-20 07:24 +0000
                                Re: Encapsulation, inheritance and polymorphism rusi <rustompmody@gmail.com> - 2012-07-20 01:21 -0700
                            Re: Encapsulation, inheritance and polymorphism Paul Rudin <paul.nospam@rudin.co.uk> - 2012-07-19 18:22 +0100
                            Re: Encapsulation, inheritance and polymorphism Tim Chase <python.list@tim.thechases.com> - 2012-07-19 13:20 -0500
                            Re: Encapsulation, inheritance and polymorphism Chris Angelico <rosuav@gmail.com> - 2012-07-20 04:28 +1000
                            Re: Encapsulation, inheritance and polymorphism Tim Chase <python.list@tim.thechases.com> - 2012-07-19 13:50 -0500
                              Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-20 08:11 +0000
                                Re: Encapsulation, inheritance and polymorphism Erik Max Francis <max@alcyone.com> - 2012-07-20 02:08 -0700
                                  Re: Encapsulation, inheritance and polymorphism "BartC" <bc@freeuk.com> - 2012-07-20 11:28 +0100
                                    Re: Encapsulation, inheritance and polymorphism Erik Max Francis <max@alcyone.com> - 2012-07-21 14:32 -0700
                                      Re: Encapsulation, inheritance and polymorphism Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-23 16:36 +0000
                            Re: Encapsulation, inheritance and polymorphism Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-07-19 16:47 -0400
                              Re: Encapsulation, inheritance and polymorphism John Gordon <gordon@panix.com> - 2012-07-19 21:01 +0000
                                Re: Encapsulation, inheritance and polymorphism Chris Angelico <rosuav@gmail.com> - 2012-07-20 08:20 +1000
                                  Re: Encapsulation, inheritance and polymorphism John Gordon <gordon@panix.com> - 2012-07-19 22:23 +0000
                                  Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-20 08:27 +0000
                                    Re: Encapsulation, inheritance and polymorphism Virgil Stokes <vs@it.uu.se> - 2012-07-20 11:05 +0200
                                      Re: Encapsulation, inheritance and polymorphism Hans Mulder <hansmu@xs4all.nl> - 2012-07-20 19:45 +0200
                                      Re: Encapsulation, inheritance and polymorphism Erik Max Francis <max@alcyone.com> - 2012-07-21 14:28 -0700
                                    Re: Encapsulation, inheritance and polymorphism Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-07-20 13:57 -0400
                                Re: Encapsulation, inheritance and polymorphism Ian Kelly <ian.g.kelly@gmail.com> - 2012-07-19 15:13 -0600
                                Re: Encapsulation, inheritance and polymorphism Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-07-19 17:30 -0400
                                Re: Encapsulation, inheritance and polymorphism Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-07-20 10:00 +0100
                      Re: Encapsulation, inheritance and polymorphism Terry Reedy <tjreedy@udel.edu> - 2012-07-19 02:11 -0400
                    Re: Encapsulation, inheritance and polymorphism Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-23 16:18 +0000
                      Re: Encapsulation, inheritance and polymorphism Chris Angelico <rosuav@gmail.com> - 2012-07-24 02:15 +1000
                      Re: Encapsulation, inheritance and polymorphism Robert Miles <robertmiles@teranews.com> - 2012-08-19 00:21 -0500
                        Re: Encapsulation, inheritance and polymorphism Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-19 09:55 +0100
                          Re: Encapsulation, inheritance and polymorphism lipska the kat <lipskathekat@yahoo.co.uk> - 2012-08-19 12:50 +0100
                            Re: Encapsulation, inheritance and polymorphism Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-19 13:06 +0100
            Re: Encapsulation, inheritance and polymorphism Ethan Furman <ethan@stoneleaf.us> - 2012-07-17 11:43 -0700
            Re: Encapsulation, inheritance and polymorphism Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-07-17 15:05 -0400
            Re: Encapsulation, inheritance and polymorphism Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-07-17 20:33 +0100
            Re: Encapsulation, inheritance and polymorphism Ian <hobson42@gmail.com> - 2012-07-17 19:59 +0100
          Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-18 12:58 +0000
            Re: Encapsulation, inheritance and polymorphism Roy Smith <roy@panix.com> - 2012-07-18 09:07 -0400
              Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-18 14:31 +0000
            Re: Encapsulation, inheritance and polymorphism Dave Angel <d@davea.name> - 2012-07-18 12:33 -0400
              Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-19 01:23 +0000
        Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-18 12:43 +0000
        Re: Encapsulation, inheritance and polymorphism Grant Edwards <invalid@invalid.invalid> - 2012-07-18 14:34 +0000
          Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-18 15:48 +0100
            Re: Encapsulation, inheritance and polymorphism Chris Angelico <rosuav@gmail.com> - 2012-07-19 01:09 +1000
              Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-18 16:36 +0100
            Re: Encapsulation, inheritance and polymorphism Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-19 01:14 +0000
              Re: Encapsulation, inheritance and polymorphism MRAB <python@mrabarnett.plus.com> - 2012-07-19 02:28 +0100
                Re: Encapsulation, inheritance and polymorphism "OKB (not okblacke)" <brenNOSPAMbarn@NObrenSPAMbarn.net> - 2012-07-19 16:52 +0000
          Re: Encapsulation, inheritance and polymorphism Andrew Berg <bahamutzero8825@gmail.com> - 2012-07-18 10:00 -0500
    Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 13:01 +0100
      Re: Encapsulation, inheritance and polymorphism Terry Reedy <tjreedy@udel.edu> - 2012-07-17 13:24 -0400
        Re: Encapsulation, inheritance and polymorphism Lipska the Kat <lipska@lipskathekat.com> - 2012-07-17 19:21 +0100
      Re: Encapsulation, inheritance and polymorphism MRAB <python@mrabarnett.plus.com> - 2012-07-17 18:43 +0100
      Re: Encapsulation, inheritance and polymorphism Tim Chase <python.list@tim.thechases.com> - 2012-07-17 12:56 -0500
      Re: Encapsulation, inheritance and polymorphism Arnaud Delobelle <arnodel@gmail.com> - 2012-07-18 11:35 +0100

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#25691

"Erik Max Francis" <max@alcyone.com> wrote in message
news:GsKdnWOQPKOOvZTNnZ2dnUVZ5s2dnZ2d@giganews.com...
> On 07/20/2012 01:11 AM, Steven D'Aprano wrote:
>> On Thu, 19 Jul 2012 13:50:36 -0500, Tim Chase wrote:

>> I'm reminded of Graham's Number, which is so large that there aren't
>> enough molecules in the universe to write it out as a power tower
>> a^b^c^d^..., or even in a tower of hyperpowers a^^b^^c^^d^^... It was the
>> provable upper bound to a question to which experts in the field thought
>> the most likely answer was ... six.
>>
>> (The bounds have since been reduced: the lower bound is now 13, and the
>> upper bound is *much* smaller than Graham's Number but still
>> inconceivably ginormous.)
>
> You don't even need to go that high.  Even a run-of-the-mill googol
> (10^100) is far larger than the total number of elementary particles in
> the observable Universe.

But you can write it down, even as a straightforward number, without any 
problem. Perhaps a googolplex (10^10^100 iirc) would be difficult to write 
it down in full, but I have just represented it as an exponent with little 
difficulty.

These bigger numbers can't be written down, because there will never be
enough material, even using multiple systems of exponents.

(A few years ago the biggest number I'd heard of was Skewes' Number
(something like 10^10^10^34), but even that is trivial to write using
conventional exponents as I've just shown. Graham's Number is in a different
class altogether.)

-- 
Bartc 

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#25770

On 07/20/2012 03:28 AM, BartC wrote:
> "Erik Max Francis" <max@alcyone.com> wrote in message
> news:GsKdnWOQPKOOvZTNnZ2dnUVZ5s2dnZ2d@giganews.com...
>> On 07/20/2012 01:11 AM, Steven D'Aprano wrote:
>>> On Thu, 19 Jul 2012 13:50:36 -0500, Tim Chase wrote:
>
>>> I'm reminded of Graham's Number, which is so large that there aren't
>>> enough molecules in the universe to write it out as a power tower
>>> a^b^c^d^..., or even in a tower of hyperpowers a^^b^^c^^d^^... It was
>>> the
>>> provable upper bound to a question to which experts in the field thought
>>> the most likely answer was ... six.
>>>
>>> (The bounds have since been reduced: the lower bound is now 13, and the
>>> upper bound is *much* smaller than Graham's Number but still
>>> inconceivably ginormous.)
>>
>> You don't even need to go that high. Even a run-of-the-mill googol
>> (10^100) is far larger than the total number of elementary particles in
>> the observable Universe.
>
> But you can write it down, even as a straightforward number, without any
> problem. Perhaps a googolplex (10^10^100 iirc) would be difficult to
> write it down in full, but I have just represented it as an exponent
> with little difficulty.
>
> These bigger numbers can't be written down, because there will never be
> enough material, even using multiple systems of exponents.

But that's true for precisely the same reason as what I said.  If you're 
going to write a number down in standard format (whatever the base), 
then the number of digits needed scales as the logarithm of the number 
(again, whatever the base).  log_10 10^100 is trivially 100, so a rough 
order of magnitude in that form is easy to write down.  But the log_10 
10^10^100 is 10^100 = a googol, which is already more than the number of 
elementary particles in the observable Universe.

> (A few years ago the biggest number I'd heard of was Skewes' Number
> (something like 10^10^10^34), but even that is trivial to write using
> conventional exponents as I've just shown. Graham's Number is in a
> different
> class altogether.)

Anything's trivial to "write down."  Just say "the number such that ..." 
and you've written it down.  Even "numbers" that aren't really numbers, 
such as transfinite cardinals!

-- 
Erik Max Francis && max@alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Jabber erikmaxfrancis
   She's your moon, she's your sun / She could even be the one
    -- Nik Kershaw

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#25901

In article <Oc-dnUqKG91pgpbNnZ2dnUVZ5vGdnZ2d@giganews.com>,
Erik Max Francis  <max@alcyone.com> wrote:
<SNIP>
>Anything's trivial to "write down."  Just say "the number such that ..."
>and you've written it down.  Even "numbers" that aren't really numbers,
>such as transfinite cardinals!

Now it isn't trivial to write down.
It has been proven (of course in an anti-intuitionistic 1] ,
Cantor-universe) that there is always a larger cardinal, and that
there is no consistent way to write them down. In other ways, you
have to keep inventing new notations, hardly a trivial matter.
See also Hofstaedter: Goedel, Escher, Bach.

>
>--
>Erik Max Francis && max@alcyone.com && http://www.alcyone.com/max/

Groetjes Albert

1] The likes of Brouwer found these silly exercises.)

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert@spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst

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#25650

On Thu, 19 Jul 2012 13:20:28 -0500, Tim Chase
<python.list@tim.thechases.com> declaimed the following in
gmane.comp.python.general:


> Sure it terminates...If you don't run out of RAM to represent the
> number "i" in question, there's also this "heat death of the
> universe" limit I keep hearing about ;-)
>
	Since the current evidence indicates the universe will just keep
expanding, it's more of a "deep freeze death..."
-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
        wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/

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#25651

In <mailman.2317.1342730879.4697.python-list@python.org> Dennis Lee Bieber <wlfraed@ix.netcom.com> writes:

> > Sure it terminates...If you don't run out of RAM to represent the
> > number "i" in question, there's also this "heat death of the
> > universe" limit I keep hearing about ;-)
> >
> 	Since the current evidence indicates the universe will just keep
> expanding, it's more of a "deep freeze death..."

Heat death means *lack* of heat.

-- 
John Gordon                   A is for Amy, who fell down the stairs
gordon@panix.com              B is for Basil, assaulted by bears
                                -- Edward Gorey, "The Gashlycrumb Tinies"

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#25655

On Fri, Jul 20, 2012 at 7:01 AM, John Gordon <gordon@panix.com> wrote:
> In <mailman.2317.1342730879.4697.python-list@python.org> Dennis Lee Bieber <wlfraed@ix.netcom.com> writes:
>
>> > Sure it terminates...If you don't run out of RAM to represent the
>> > number "i" in question, there's also this "heat death of the
>> > universe" limit I keep hearing about ;-)
>> >
>>       Since the current evidence indicates the universe will just keep
>> expanding, it's more of a "deep freeze death..."
>
> Heat death means *lack* of heat.

The second law of thermodynamics states that energy tends to go from
higher states to lower, with heat being the very lowest. It's possible
to do work using (say) kinetic energy, and in the process, some of
that energy becomes heat. It's also possible to do work with any
difference in temperature (eg Stirling engines), so the state of the
universe in which it's no longer possible to do any work will be one
in which all energy is heat and everything's at the same temperature.
That doesn't mean a lack of heat; in fact, it implies that there'll be
rather more heat than there now is, because we currently have a whole
lot of chemical energy available to be used.

But in any case, that's a looooooooong way off...

ChrisA

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#25656

In <mailman.2320.1342736459.4697.python-list@python.org> Chris Angelico <rosuav@gmail.com> writes:

> The second law of thermodynamics states that energy tends to go from
> higher states to lower, with heat being the very lowest. It's possible
> to do work using (say) kinetic energy, and in the process, some of
> that energy becomes heat. It's also possible to do work with any
> difference in temperature (eg Stirling engines), so the state of the
> universe in which it's no longer possible to do any work will be one
> in which all energy is heat and everything's at the same temperature.
> That doesn't mean a lack of heat; in fact, it implies that there'll be
> rather more heat than there now is, because we currently have a whole
> lot of chemical energy available to be used.

*mind blown*

-- 
John Gordon                   A is for Amy, who fell down the stairs
gordon@panix.com              B is for Basil, assaulted by bears
                                -- Edward Gorey, "The Gashlycrumb Tinies"

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#25680

On Fri, 20 Jul 2012 08:20:57 +1000, Chris Angelico wrote:

>>>       Since the current evidence indicates the universe will just keep
>>> expanding, it's more of a "deep freeze death..."
>>
>> Heat death means *lack* of heat.
> 
> The second law of thermodynamics states that energy tends to go from
> higher states to lower, with heat being the very lowest. It's possible
> to do work using (say) kinetic energy, and in the process, some of that
> energy becomes heat. It's also possible to do work with any difference
> in temperature (eg Stirling engines), so the state of the universe in
> which it's no longer possible to do any work will be one in which all
> energy is heat and everything's at the same temperature. That doesn't
> mean a lack of heat; in fact, it implies that there'll be rather more
> heat than there now is, because we currently have a whole lot of
> chemical energy available to be used.

Yes, but the point is, that heat will be *incredibly* diffuse, 
essentially spread over the entire universe, which will be MUCH bigger 
than it is now, and hence the temperature will be low even though the 
total amount of heat will be high.

The average temperature of the universe now is about 2.7 degrees above 
absolute zero (i.e. 2.7 K, -270.45 C or -454.81 F), with individual 
hotspots reaching into millions of degrees or higher. By the time the 
last of the stars burn out, the average temperature will be a minuscule 
fraction of a degree above absolute zero, and the only hotspots will be 
the slowly cooling neutron stars.


> But in any case, that's a looooooooong way off...

I once went to an astronomy lecture where the lecturer was talking about 
the eventual death of the sun. He said, "In about 10 billion years, the 
sun will consume almost all of its fuel. It will cool and expand into a 
red giant, and the earth will be engulfed by the expanded sun and 
destroyed."

This fellow sitting next to me got all agitated, stood up and cried out, 
"Does the government know about this? We have to do something!"

The lecturer said "Don't worry sir, there's no need to panic, this won't 
happen for billions of years."

The fellow looked relived and said "Oh thank god, I thought you said 
*million*!"



-- 
Steven

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#25688

On 20-Jul-2012 10:27, Steven D'Aprano wrote:
> On Fri, 20 Jul 2012 08:20:57 +1000, Chris Angelico wrote:
>
>>>>        Since the current evidence indicates the universe will just keep
>>>> expanding, it's more of a "deep freeze death..."
>>> Heat death means *lack* of heat.
>> The second law of thermodynamics states that energy tends to go from
>> higher states to lower, with heat being the very lowest. It's possible
>> to do work using (say) kinetic energy, and in the process, some of that
>> energy becomes heat. It's also possible to do work with any difference
>> in temperature (eg Stirling engines), so the state of the universe in
>> which it's no longer possible to do any work will be one in which all
>> energy is heat and everything's at the same temperature. That doesn't
>> mean a lack of heat; in fact, it implies that there'll be rather more
>> heat than there now is, because we currently have a whole lot of
>> chemical energy available to be used.
> Yes, but the point is, that heat will be *incredibly* diffuse,
> essentially spread over the entire universe, which will be MUCH bigger
> than it is now, and hence the temperature will be low even though the
> total amount of heat will be high.
>
> The average temperature of the universe now is about 2.7 degrees above
> absolute zero (i.e. 2.7 K, -270.45 C or -454.81 F), with individual
> hotspots reaching into millions of degrees or higher. By the time the
> last of the stars burn out, the average temperature will be a minuscule
> fraction of a degree above absolute zero, and the only hotspots will be
> the slowly cooling neutron stars.
>
>
>> But in any case, that's a looooooooong way off...
> I once went to an astronomy lecture where the lecturer was talking about
> the eventual death of the sun. He said, "In about 10 billion years, the
> sun will consume almost all of its fuel. It will cool and expand into a
> red giant, and the earth will be engulfed by the expanded sun and
> destroyed."
>
> This fellow sitting next to me got all agitated, stood up and cried out,
> "Does the government know about this? We have to do something!"
>
> The lecturer said "Don't worry sir, there's no need to panic, this won't
> happen for billions of years."
>
> The fellow looked relived and said "Oh thank god, I thought you said
> *million*!"
>
>
>
How does this relate to the python list?

"This mailing list is a general discussion list for the Python programming 
language." --- from http://mail.python.org/mailman/listinfo/python-list/

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#25697

On 20/07/12 11:05:09, Virgil Stokes wrote:
> On 20-Jul-2012 10:27, Steven D'Aprano wrote:
>> On Fri, 20 Jul 2012 08:20:57 +1000, Chris Angelico wrote:
>>
>>>>>        Since the current evidence indicates the universe will just
>>>>> keep
>>>>> expanding, it's more of a "deep freeze death..."
>>>> Heat death means *lack* of heat.
>>> The second law of thermodynamics states that energy tends to go from
>>> higher states to lower, with heat being the very lowest. It's possible
>>> to do work using (say) kinetic energy, and in the process, some of that
>>> energy becomes heat. It's also possible to do work with any difference
>>> in temperature (eg Stirling engines), so the state of the universe in
>>> which it's no longer possible to do any work will be one in which all
>>> energy is heat and everything's at the same temperature. That doesn't
>>> mean a lack of heat; in fact, it implies that there'll be rather more
>>> heat than there now is, because we currently have a whole lot of
>>> chemical energy available to be used.
>> Yes, but the point is, that heat will be *incredibly* diffuse,
>> essentially spread over the entire universe, which will be MUCH bigger
>> than it is now, and hence the temperature will be low even though the
>> total amount of heat will be high.
>>
>> The average temperature of the universe now is about 2.7 degrees above
>> absolute zero (i.e. 2.7 K, -270.45 C or -454.81 F), with individual
>> hotspots reaching into millions of degrees or higher. By the time the
>> last of the stars burn out, the average temperature will be a minuscule
>> fraction of a degree above absolute zero, and the only hotspots will be
>> the slowly cooling neutron stars.
>>
>>
>>> But in any case, that's a looooooooong way off...
>> I once went to an astronomy lecture where the lecturer was talking about
>> the eventual death of the sun. He said, "In about 10 billion years, the
>> sun will consume almost all of its fuel. It will cool and expand into a
>> red giant, and the earth will be engulfed by the expanded sun and
>> destroyed."
>>
>> This fellow sitting next to me got all agitated, stood up and cried out,
>> "Does the government know about this? We have to do something!"
>>
>> The lecturer said "Don't worry sir, there's no need to panic, this won't
>> happen for billions of years."
>>
>> The fellow looked relived and said "Oh thank god, I thought you said
>> *million*!"
>>
> How does this relate to the python list?

This thread is as coherent as a typical episode of
Monty Python's Flying Circus :-)


-- HansM

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#25769

On 07/20/2012 02:05 AM, Virgil Stokes wrote:
> On 20-Jul-2012 10:27, Steven D'Aprano wrote:
>> The fellow looked relived and said "Oh thank god, I thought you said
>> *million*!"
>
> How does this relate to the python list?

It's also a seriously old joke.

-- 
Erik Max Francis && max@alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Jabber erikmaxfrancis
   She's your moon, she's your sun / She could even be the one
    -- Nik Kershaw

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#25698

On Fri, 20 Jul 2012 11:05:09 +0200, Virgil Stokes <vs@it.uu.se>
declaimed the following in gmane.comp.python.general:

> How does this relate to the python list?
> 
	Ouroboros
-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
        wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/

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#25673

On Thu, Jul 19, 2012 at 3:01 PM, John Gordon <gordon@panix.com> wrote:
> In <mailman.2317.1342730879.4697.python-list@python.org> Dennis Lee Bieber <wlfraed@ix.netcom.com> writes:
>
>> > Sure it terminates...If you don't run out of RAM to represent the
>> > number "i" in question, there's also this "heat death of the
>> > universe" limit I keep hearing about ;-)
>> >
>>       Since the current evidence indicates the universe will just keep
>> expanding, it's more of a "deep freeze death..."
>
> Heat death means *lack* of heat.

Actually actually it means *uniformity* of heat, i.e. that the entire
universe is in thermodynamic equilibrium and so it is impossible to
perform work.  So heat death is expected regardless of whether the
universe ultimately collapses or expands indefinitely.

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#25674

On Thu, Jul 19, 2012 at 5:01 PM, John Gordon <gordon@panix.com> wrote:
>>       Since the current evidence indicates the universe will just keep
>> expanding, it's more of a "deep freeze death..."
>
> Heat death means *lack* of heat.

But it doesn't mean low temperature! The term is agnostic as to what
the temperature of the universe will be.

-- Devin

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#25686

On 19/07/2012 22:13, Ian Kelly wrote:
> On Thu, Jul 19, 2012 at 3:01 PM, John Gordon <gordon@panix.com> wrote:
>> In <mailman.2317.1342730879.4697.python-list@python.org> Dennis Lee Bieber <wlfraed@ix.netcom.com> writes:
>>
>>>> Sure it terminates...If you don't run out of RAM to represent the
>>>> number "i" in question, there's also this "heat death of the
>>>> universe" limit I keep hearing about ;-)
>>>>
>>>        Since the current evidence indicates the universe will just keep
>>> expanding, it's more of a "deep freeze death..."
>>
>> Heat death means *lack* of heat.
>
> Actually actually it means *uniformity* of heat, i.e. that the entire
> universe is in thermodynamic equilibrium and so it is impossible to
> perform work.  So heat death is expected regardless of whether the
> universe ultimately collapses or expands indefinitely.
>

All of this will pale into complete insignificance provided that England 
beat South Africa in the current cricket test match series and retain 
their world no.1 ranking.  Of course if they lose the universe will 
collapse immediately or expand so far that it tears itself to tiny 
little pieces.  Even The Ashes won't survive, something I should perhaps 
take up with the MCC.

-- 
Cheers.

Mark Lawrence.

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#25609

On 7/18/2012 10:40 AM, Lipska the Kat wrote:

> fact ... and I have never been forced to admit that I don't know what I
> wrote six months ago.

That is an explicit objective of Python's design.

> Python looks like an interesting language and I will certainly spend
> time getting to know it but at the moment it seems to me that calling it
> an Object Oriented language is just plain misleading.

I just call it object-based and let be done with it, as I have no 
interest in arguing 'Object Oriented'.

What perhaps *you* need to know, given your background, is that nearly 
all syntax and most builtin callables wrap special method calls that can 
be defined on user classes.

'a + b' is executed as something like

try:
   return a.__add__(b)  # or the C type slot equivalent
except: # not sure what is actually caught
   try:
     return b.__radd__(a)  # r(everse)add
   except: # ditto
     raise TypeError("unsupported operand type(s) for +: {} and 
{}".format(a, b))

[Syntax exceptions: =, and, or]

'len(x)' calls x.__len__ and checks that the return value can be 
interpreted as an integer (I believe that means that it is an int or has 
an __index__ method, so that it can be used as a sequence index) and 
that its value is >= 0.

-- 
Terry Jan Reedy

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#25888

In article <5006b48a$0$29978$c3e8da3$5496439d@news.astraweb.com>,
Steven D'Aprano  <steve+comp.lang.python@pearwood.info> wrote:
<SNIP.
>Even with a break, why bother continuing through the body of the function
>when you already have the result? When your calculation is done, it's
>done, just return for goodness sake. You wouldn't write a search that
>keeps going after you've found the value that you want, out of some
>misplaced sense that you have to look at every value. Why write code with
>unnecessary guard values and temporary variables out of a misplaced sense
>that functions must only have one exit?

Example from recipee's:

Stirr until the egg white is stiff.

Alternative:
Stirr egg white for half an hour,
but if the egg white is stiff keep your spoon still.

(Cooking is not my field of expertise, so the wording may
not be quite appropriate. )

>--
>Steven

Groetjes Albert

--
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert@spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst

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#25898

On Tue, Jul 24, 2012 at 2:18 AM, Albert van der Horst
<albert@spenarnc.xs4all.nl> wrote:
> Example from recipee's:
>
> Stirr until the egg white is stiff.
>
> Alternative:
> Stirr egg white for half an hour,
> but if the egg white is stiff keep your spoon still.
>
> (Cooking is not my field of expertise, so the wording may
> not be quite appropriate. )

Method.
Take egg white from refrigerator.
Put egg white into mixing bowl.
Stir for 30 minutes.
Stir the egg white.
Stir the egg white until stirred.

That's valid code, incidentally. Not Python code, but it is
executable. And it includes a useless count-down-to-zero loop.

ChrisA

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#27346

On 7/23/2012 11:18 AM, Albert van der Horst wrote:
> In article <5006b48a$0$29978$c3e8da3$5496439d@news.astraweb.com>,
> Steven D'Aprano  <steve+comp.lang.python@pearwood.info> wrote:
> <SNIP.
>> Even with a break, why bother continuing through the body of the function
>> when you already have the result? When your calculation is done, it's
>> done, just return for goodness sake. You wouldn't write a search that
>> keeps going after you've found the value that you want, out of some
>> misplaced sense that you have to look at every value. Why write code with
>> unnecessary guard values and temporary variables out of a misplaced sense
>> that functions must only have one exit?
>
> Example from recipee's:
>
> Stirr until the egg white is stiff.
>
> Alternative:
> Stirr egg white for half an hour,
> but if the egg white is stiff keep your spoon still.
>
> (Cooking is not my field of expertise, so the wording may
> not be quite appropriate. )
>
>> --
>> Steven
>
> Groetjes Albert

Note that you forgot applying enough heat to do the cooking.

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#27364

On 19/08/2012 06:21, Robert Miles wrote:
> On 7/23/2012 11:18 AM, Albert van der Horst wrote:
>> In article <5006b48a$0$29978$c3e8da3$5496439d@news.astraweb.com>,
>> Steven D'Aprano  <steve+comp.lang.python@pearwood.info> wrote:
>> <SNIP.
>>> Even with a break, why bother continuing through the body of the
>>> function
>>> when you already have the result? When your calculation is done, it's
>>> done, just return for goodness sake. You wouldn't write a search that
>>> keeps going after you've found the value that you want, out of some
>>> misplaced sense that you have to look at every value. Why write code
>>> with
>>> unnecessary guard values and temporary variables out of a misplaced
>>> sense
>>> that functions must only have one exit?
>>
>> Example from recipee's:
>>
>> Stirr until the egg white is stiff.
>>
>> Alternative:
>> Stirr egg white for half an hour,
>> but if the egg white is stiff keep your spoon still.
>>
>> (Cooking is not my field of expertise, so the wording may
>> not be quite appropriate. )
>>
>>> --
>>> Steven
>>
>> Groetjes Albert
>
> Note that you forgot applying enough heat to do the cooking.
>
>

Surely the first check is your filing system to make sure that you've 
paid the utilties bills so you've got gas and or electricity to apply 
the heat.  Either that or you hire Ray Mears to produce the spark needed 
to light the fire :)

-- 
Cheers.

Mark Lawrence.

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