f



Problem with a problem

Hello,

take a grammar G with alphabet {0,1} such that (the word problem for)
the language
L_G={w in (0+1)*|w\in L(G)}
is very complex, say in PSPACE or some higher complexity class.

Now consider an "easy" problem EASY like: "Is an element of L_G in
L_G?". Well, this seems to be fairly easy because the answer is "yes"
in any case. Hence the problem should be of small complexity.

But if one models such a decision problem one has to construct a
language L with alphabet A such that the word problem for L reflects
exactly the decision problem which one is interested in. For example
the problem CLIQUE has been modeled by the word problem for the
language L_CLIQUE={<G,k> in (0+1)* | G finite graph, k natural number
and G has a k-clique}.

Now my problem arises: In the CLIQUE case one can think of an "input"
of the turing machine T which should decide the word problem for
L_CLIQUE already as a pair <G,k> in the wanted form and one has not to
consider an arbitrary string x of (0+1)*. This is possible because the
language L'={<G,k> in (0+1)* | G finite graph, k natural number} can
be produced by an easy context-free grammar and therefore the word
problem for L' is of a low complexity like P. So if one considers the
word problem for the language L_CLIQUE one can decide in P if an
arbitrary string x of (0+1)* is of the form <G,k> and if it is not the
turing machine T can stop without accepting immediately. Therefore the
complexity of L_CLIQUE is polynomial+"complexity of the real problem
CLIQUE".

But what happens in the above case where the word problem for L_G is
rather difficult? Even if the "real problem" is very easy the
complexity of L_G would be exponential+"complexity of the real problem
EASY". Hence the problem EASY is a very complex one, right?

* An example for such a language L(G)  is perhaps the following one:
In a previous post it has been shown to me that the language L={e,
1,11,1111,11111111,...} is not context-free but context-sensitive and
the word problem for arbitrary context-sensitive languages is more
complex than PSPACE so this language L has a great chance to be such
complex.

* For a language L it is defined to be in a complexity class, e.g. P
or PSPACE, iff the word problem of that language is in that complexity
class.

Thanks,
Sancho
0
7/10/2008 8:46:45 AM
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On Jul 10, 4:46=A0am, sanchopanch...@web.de wrote:
> Hello,
>
> take a grammar G with alphabet {0,1} such that (the word problem for)
> the language
> L_G=3D{w in (0+1)*|w\in L(G)}
> is very complex, say in PSPACE or some higher complexity class.
>
> Now consider an "easy" problem EASY like: "Is an element of L_G in
> L_G?". Well, this seems to be fairly easy because the answer is "yes"
> in any case. Hence the problem should be of small complexity.

The lowest complexity imaginable namely the 'constant' complexity
class, or 'True' (or 'False'). What -is- the official name for this?


> But if one models such a decision problem one has to construct a
> language L with alphabet A such that the word problem for L reflects
> exactly the decision problem which one is interested in. For example
> the problem CLIQUE has been modeled by the word problem for the
> language L_CLIQUE=3D{<G,k> in (0+1)* | G finite graph, k natural number
> and G has a k-clique}.

OK. That's what it boils down to formally.


> Now my problem arises: In the CLIQUE case one can think of an "input"
> of the turing machine T which should decide the word problem for
> L_CLIQUE already as a pair <G,k> in the wanted form and one has not to
> consider an arbitrary string x of (0+1)*. This is possible because the
> language L'=3D{<G,k> in (0+1)* | G finite graph, k natural number} can
> be produced by an easy context-free grammar and therefore the word
> problem for L' is of a low complexity like P. So if one considers the
> word problem for the language L_CLIQUE one can decide in P if an
> arbitrary string x of (0+1)* is of the form <G,k>

I don't understand how you can do that. How do you know you can write
a CFG that accepts only graphs with cliques >=3D k? Hm...maybe you can
use CFGs but not immediately. I think you'd have to preprocess your
original graph (of size V+E) into another graph of much bigger size.

> and if it is not the
> turing machine T can stop without accepting immediately. Therefore the
> complexity of L_CLIQUE is polynomial+"complexity of the real problem
> CLIQUE".
>
> But what happens in the above case where the word problem for L_G is
> rather difficult? Even if the "real problem" is very easy the
> complexity of L_G would be exponential+"complexity of the real problem
> EASY". Hence the problem EASY is a very complex one, right?
>
> * An example for such a language L(G) =A0is perhaps the following one:
> In a previous post it has been shown to me that the language L=3D{e,
> 1,11,1111,11111111,...} is not context-free but context-sensitive and
> the word problem for arbitrary context-sensitive languages is more
> complex than PSPACE so this language L has a great chance to be such
> complex.

I'm not sure I understand the direction this is going, but just to
repeat the small fact, CSL-membership is PSPACE-complete.

Mitch
0
maharri (66)
7/10/2008 2:19:01 PM
Thank you for your answer.

On 10 Jul., 16:19, Mitch <maha...@gmail.com> wrote:
> On Jul 10, 4:46=A0am, sanchopanch...@web.de wrote:
>
> > Hello,
>
> > take a grammar G with alphabet {0,1} such that (the word problem for)
> > the language
> > L_G=3D{w in (0+1)*|w\in L(G)}
> > is very complex, say in PSPACE or some higher complexity class.
>
> > Now consider an "easy" problem EASY like: "Is an element of L_G in
> > L_G?". Well, this seems to be fairly easy because the answer is "yes"
> > in any case. Hence the problem should be of small complexity.
>
> The lowest complexity imaginable namely the 'constant' complexity
> class, or 'True' (or 'False'). What -is- the official name for this?

Ok, something like that...

> > But if one models such a decision problem one has to construct a
> > language L with alphabet A such that the word problem for L reflects
> > exactly the decision problem which one is interested in. For example
> > the problem CLIQUE has been modeled by the word problem for the
> > language L_CLIQUE=3D{<G,k> in (0+1)* | G finite graph, k natural number
> > and G has a k-clique}.
>
> OK. That's what it boils down to formally.
>
> > Now my problem arises: In the CLIQUE case one can think of an "input"
> > of the turing machine T which should decide the word problem for
> > L_CLIQUE already as a pair <G,k> in the wanted form and one has not to
> > consider an arbitrary string x of (0+1)*. This is possible because the
> > language L'=3D{<G,k> in (0+1)* | G finite graph, k natural number} can
> > be produced by an easy context-free grammar and therefore the word
> > problem for L' is of a low complexity like P. So if one considers the
> > word problem for the language L_CLIQUE one can decide in P if an
> > arbitrary string x of (0+1)* is of the form <G,k>
>
> I don't understand how you can do that. How do you know you can write
> a CFG that accepts only graphs with cliques >=3D k? Hm...maybe you can
> use CFGs but not immediately. I think you'd have to preprocess your
> original graph (of size V+E) into another graph of much bigger size.

No, this is not what I mean: You can write a CFG that produces ->all<-
pairs <G,k> such that G is a finite graph and k a natural number!
Therefore you don't have to consider arbitrary inputs of (0+1)* for
your CLIQUE-algorithm but only ones which are already of the form
<G,k>. Therefore the complexity of  L_CLIQUE is polynomial+"complexity
of the real problem CLIQUE" as I have said before. Do you understand
my problem?

>
> > and if it is not the
> > turing machine T can stop without accepting immediately. Therefore the
> > complexity of L_CLIQUE is polynomial+"complexity of the real problem
> > CLIQUE".
>
> > But what happens in the above case where the word problem for L_G is
> > rather difficult? Even if the "real problem" is very easy the
> > complexity of L_G would be exponential+"complexity of the real problem
> > EASY". Hence the problem EASY is a very complex one, right?
>
> > * An example for such a language L(G) =A0is perhaps the following one:
> > In a previous post it has been shown to me that the language L=3D{e,
> > 1,11,1111,11111111,...} is not context-free but context-sensitive and
> > the word problem for arbitrary context-sensitive languages is more
> > complex than PSPACE so this language L has a great chance to be such
> > complex.
>
> I'm not sure I understand the direction this is going, but just to
> repeat the small fact, CSL-membership is PSPACE-complete.

Thanks,
S.



0
7/10/2008 2:32:30 PM
On Jul 10, 10:32=A0am, sanchopanch...@web.de wrote:
> Thank you for your answer.
>
> On 10 Jul., 16:19, Mitch <maha...@gmail.com> wrote:
>
> > On Jul 10, 4:46=A0am, sanchopanch...@web.de wrote:
>
> > > Now my problem arises: In the CLIQUE case one can think of an "input"
> > > of the turing machine T which should decide the word problem for
> > > L_CLIQUE already as a pair <G,k> in the wanted form and one has not t=
o
> > > consider an arbitrary string x of (0+1)*. This is possible because th=
e
> > > language L'=3D{<G,k> in (0+1)* | G finite graph, k natural number} ca=
n
> > > be produced by an easy context-free grammar and therefore the word
> > > problem for L' is of a low complexity like P. So if one considers the
> > > word problem for the language L_CLIQUE one can decide in P if an
> > > arbitrary string x of (0+1)* is of the form <G,k>
>
> > I don't understand how you can do that. How do you know you can write
> > a CFG that accepts only graphs with cliques >=3D k? Hm...maybe you can
> > use CFGs but not immediately. I think you'd have to preprocess your
> > original graph (of size V+E) into another graph of much bigger size.
>
> No, this is not what I mean: You can write a CFG that produces ->all<-
> pairs <G,k> such that G is a finite graph and k a natural number!

OK. Yes. (but with no CLIQUE relevant processing, right?)

> Therefore you don't have to consider arbitrary inputs of (0+1)* for
> your CLIQUE-algorithm but only ones which are already of the form
> <G,k>. Therefore the complexity of =A0L_CLIQUE is polynomial+"complexity
> of the real problem CLIQUE" as I have said before. Do you understand
> my problem?

OK. I think I understand. That's fine then. First just check that the
input is of form 'a graph and a number' and -then- do the real work of
checking if the largest clique of that graph is of size >=3D the given
number.

To this I'd have to say that that is pretty much understood by any
complexity problem...that it is trivial to check that the input is of
appropriate form. And that this trivial check is pretty much inherent
and ignored. (I'm not exactly sure how that might work for very small
circuit complexity classes where maybe you just assume that everything
is already in the right syntax). Frankly, I don't think the 'syntax'
check (in some sense it's all syntax, right?) is substantive.

Mitch

0
maharri (66)
7/10/2008 3:43:12 PM
On 10 Jul., 17:43, Mitch <maha...@gmail.com> wrote:
> On Jul 10, 10:32=A0am, sanchopanch...@web.de wrote:
>
>
>
> > Thank you for your answer.
>
> > On 10 Jul., 16:19, Mitch <maha...@gmail.com> wrote:
>
> > > On Jul 10, 4:46=A0am, sanchopanch...@web.de wrote:
>
> > > > Now my problem arises: In the CLIQUE case one can think of an "inpu=
t"
> > > > of the turing machine T which should decide the word problem for
> > > > L_CLIQUE already as a pair <G,k> in the wanted form and one has not=
 to
> > > > consider an arbitrary string x of (0+1)*. This is possible because =
the
> > > > language L'=3D{<G,k> in (0+1)* | G finite graph, k natural number} =
can
> > > > be produced by an easy context-free grammar and therefore the word
> > > > problem for L' is of a low complexity like P. So if one considers t=
he
> > > > word problem for the language L_CLIQUE one can decide in P if an
> > > > arbitrary string x of (0+1)* is of the form <G,k>
>
> > > I don't understand how you can do that. How do you know you can write
> > > a CFG that accepts only graphs with cliques >=3D k? Hm...maybe you ca=
n
> > > use CFGs but not immediately. I think you'd have to preprocess your
> > > original graph (of size V+E) into another graph of much bigger size.
>
> > No, this is not what I mean: You can write a CFG that produces ->all<-
> > pairs <G,k> such that G is a finite graph and k a natural number!
>
> OK. Yes. (but with no CLIQUE relevant processing, right?)

Yes, right.

> > Therefore you don't have to consider arbitrary inputs of (0+1)* for
> > your CLIQUE-algorithm but only ones which are already of the form
> > <G,k>. Therefore the complexity of =A0L_CLIQUE is polynomial+"complexit=
y
> > of the real problem CLIQUE" as I have said before. Do you understand
> > my problem?
> OK. I think I understand. That's fine then. First just check that the
> input is of form 'a graph and a number' and -then- do the real work of
> checking if the largest clique of that graph is of size >=3D the given
> number.

Yes, right.

> To this I'd have to say that that is pretty much understood by any
> complexity problem...that it is trivial to check that the input is of
> appropriate form. And that this trivial check is pretty much inherent
> and ignored. (I'm not exactly sure how that might work for very small
> circuit complexity classes where maybe you just assume that everything
> is already in the right syntax). Frankly, I don't think the 'syntax'
> check (in some sense it's all syntax, right?) is substantive.

Ok, but what about the problem EASY from the beginning? Here it is not
trivial to check that the input is of appropriate form because the
"appropriate form" is given by a "real and hard" context sensitive
language. The word problem isn't in P there.

Thanks,
Sancho
0
7/10/2008 3:56:54 PM
On Jul 10, 11:56=A0am, sanchopanch...@web.de wrote:
> Ok, but what about the problem EASY from the beginning? Here it is not
> trivial to check that the input is of appropriate form because the
> "appropriate form" is given by a "real and hard" context sensitive
> language. The word problem isn't in P there.

Hm...OK... can you give an example though? I'm trying to think of
pretty much any complexity problem and they all seem to be of the form
'given an x, decide if x has property y' and x is easily describable
syntactically.

note that it's -all- syntax whatever you're doing. if you're trying to
find a clique on input of a string describing a graph, your TM is just
playing with that string (messing it up, copying it, overwriting it,
writing strings on the blank part elsewhere for subroutines). It's all
parsing in some sense.

Mitch
0
maharri (66)
7/10/2008 4:30:09 PM
On 10 Jul., 18:30, Mitch <maha...@gmail.com> wrote:
> On Jul 10, 11:56=A0am, sanchopanch...@web.de wrote:
>
> > Ok, but what about the problem EASY from the beginning? Here it is not
> > trivial to check that the input is of appropriate form because the
> > "appropriate form" is given by a "real and hard" context sensitive
> > language. The word problem isn't in P there.
>
> Hm...OK... can you give an example though? I'm trying to think of
> pretty much any complexity problem and they all seem to be of the form
> 'given an x, decide if x has property y' and x is easily describable
> syntactically.
>
> note that it's -all- syntax whatever you're doing. if you're trying to
> find a clique on input of a string describing a graph, your TM is just
> playing with that string (messing it up, copying it, overwriting it,
> writing strings on the blank part elsewhere for subroutines). It's all
> parsing in some sense.
>
> Mitch


Yes, you are right, perhaps that's is a pathological case. An example
is the problem EASY from above: "Is an element of L in
L?" where L=3D{e,1,11,1111,11111111,...}. EASY seems to be very easy but
I suppose that it is not even in P because you have to check the form
of the input input with a high complexity because L is not context-
sensitive. Perhaps it's just a philosophical problem because you can
"represent" the problem EASY by "1=3D1?" or something else. What I
wanted to say is that sometimes it seems not only the complexity of
the "real problem" to be relevant but also the form of the input.

Thanks,
S.
0
7/10/2008 4:41:34 PM
On Jul 10, 12:41=A0pm, sanchopanch...@web.de wrote:
> On 10 Jul., 18:30, Mitch <maha...@gmail.com> wrote:
> > On Jul 10, 11:56=A0am, sanchopanch...@web.de wrote:
>
> > > Ok, but what about the problem EASY from the beginning? Here it is no=
t
> > > trivial to check that the input is of appropriate form because the
> > > "appropriate form" is given by a "real and hard" context sensitive
> > > language. The word problem isn't in P there.
>
> > Hm...OK... can you give an example though? I'm trying to think of
> > pretty much any complexity problem and they all seem to be of the form
> > 'given an x, decide if x has property y' and x is easily describable
> > syntactically.
>
> > note that it's -all- syntax whatever you're doing. if you're trying to
> > find a clique on input of a string describing a graph, your TM is just
> > playing with that string (messing it up, copying it, overwriting it,
> > writing strings on the blank part elsewhere for subroutines). It's all
> > parsing in some sense.
>
> > Mitch
>
> Yes, you are right, perhaps that's is a pathological case. An example
> is the problem EASY from above: "Is an element of L in
> L?" where L=3D{e,1,11,1111,11111111,...}. EASY seems to be very easy but
> I suppose that it is not even in P because you have to check the form
> of the input input with a high complexity because L is not context-
> sensitive.

L -is- context sensitive but not context free:

- not CFL: The language a^(2^k) (strings of a's of length a power of
2) is defeinitely -not- a CFL (by either a CFL pumping lemma (which I
don't feel like trying!) or more easily by Parikh's theorem, one of
whose readings is 'CFLs with alphabet of size 1 are regular', and also
noting that regular languages cannot create lengths (and only those
lengths) that are not linear (yes I'm being very loose here).

- is CSL: others gave example grammars that were context sensitive.


> Perhaps it's just a philosophical problem because you can
> "represent" the problem EASY by "1=3D1?" or something else. What I
> wanted to say is that sometimes it seems not only the complexity of
> the "real problem" to be relevant but also the form of the input.


I think it is easy to get mixed up with computation and parsing and
programming etc. You can write programs that get compiled (using
context free parsers, well, context sensitive actually), and then
executed. Compilers themselves are written in a language that then
gets executed.

The formal language/automata mathematics is abstracting that all away.
you just have strings and parsing rules...and the parsing steps -are-
the computation. This is easily  missed because regular languages and
CFLs don't really look like they're computing much, but then you can
do addition and multiplication and subroutines and such with TMs. (but
note that you can do binary addition with regular languages, see
exercise in Sipser)

Mitch
0
maharri (66)
7/10/2008 5:09:36 PM
On 10 Jul., 19:09, Mitch <maha...@gmail.com> wrote:
> On Jul 10, 12:41=A0pm, sanchopanch...@web.de wrote:
>
>
>
> > On 10 Jul., 18:30, Mitch <maha...@gmail.com> wrote:
> > > On Jul 10, 11:56=A0am, sanchopanch...@web.de wrote:
>
> > > > Ok, but what about the problem EASY from the beginning? Here it is =
not
> > > > trivial to check that the input is of appropriate form because the
> > > > "appropriate form" is given by a "real and hard" context sensitive
> > > > language. The word problem isn't in P there.
>
> > > Hm...OK... can you give an example though? I'm trying to think of
> > > pretty much any complexity problem and they all seem to be of the for=
m
> > > 'given an x, decide if x has property y' and x is easily describable
> > > syntactically.
>
> > > note that it's -all- syntax whatever you're doing. if you're trying t=
o
> > > find a clique on input of a string describing a graph, your TM is jus=
t
> > > playing with that string (messing it up, copying it, overwriting it,
> > > writing strings on the blank part elsewhere for subroutines). It's al=
l
> > > parsing in some sense.
>
> > > Mitch
>
> > Yes, you are right, perhaps that's is a pathological case. An example
> > is the problem EASY from above: "Is an element of L in
> > L?" where L=3D{e,1,11,1111,11111111,...}. EASY seems to be very easy bu=
t
> > I suppose that it is not even in P because you have to check the form
> > of the input input with a high complexity because L is not context-
> > sensitive.
>
> L -is- context sensitive but not context free:
>
> - not CFL: The language a^(2^k) (strings of a's of length a power of
> 2) is defeinitely -not- a CFL (by either a CFL pumping lemma (which I
> don't feel like trying!) or more easily by Parikh's theorem, one of
> whose readings is 'CFLs with alphabet of size 1 are regular', and also
> noting that regular languages cannot create lengths (and only those
> lengths) that are not linear (yes I'm being very loose here).
>
> - is CSL: others gave example grammars that were context sensitive.

Sorry, typo.

> > Perhaps it's just a philosophical problem because you can
> > "represent" the problem EASY by "1=3D1?" or something else. What I
> > wanted to say is that sometimes it seems not only the complexity of
> > the "real problem" to be relevant but also the form of the input.
>
> I think it is easy to get mixed up with computation and parsing and
> programming etc. You can write programs that get compiled (using
> context free parsers, well, context sensitive actually), and then
> executed. Compilers themselves are written in a language that then
> gets executed.
>
> The formal language/automata mathematics is abstracting that all away.
> you just have strings and parsing rules...and the parsing steps -are-
> the computation. This is easily =A0missed because regular languages and
> CFLs don't really look like they're computing much, but then you can
> do addition and multiplication and subroutines and such with TMs. (but
> note that you can do binary addition with regular languages, see
> exercise in Sipser)

Ok, thank you.

0
7/10/2008 5:11:15 PM
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Hi all, I have a Dual Core P4, which dmesg reports as (CPU0 and) CPU1: Intel(R) Pentium(R) 5 CPU 2.66GHz stepping 07 Unfortunately, it is also reporting CPU: Hyper-Threading is disabled I went through the BIOS (AMI dated 2005) and saw no option to enable HT. uname -a reports Linux hwa3 2.6.17-10-generic #2 SMP Fri Oct 13 18:45:35 UTC 2006 i686 GNU/Linux so clearly the BIOS and the kernel see the processor as dual core. Is there a utility to do this (enable hyperthreading)? Am I going to have to recompile the kernel? Is there a set of Intel dual core CPU's which does not have H...

Linux, ISE 7.1, problems, problems, problems ....
ok, ok we've beaten this subject to death already .... I just had this really radical and crazy idea: XILINX, how about a BETA program ? I mean one before you burn the CDs and make a product announcement and we are stuck with a useless plastic disc. If I look at all the issues that people are having with 7.1, they are all so trivial and easy to to solve (include a few libs, distribute a statically linked setup program, etc.). I'm sure a few of us with subscription would volunteer to test drive a pre-release version of your s/w. - I know I would. Wouldn't that be much nicer t...

Lan problems problems
Hi can anyone please offer a suggestion to a LAN Problem i have. Recently my server computer on a 3 access point lan network has been dropping out after about 10 minutes. if i disconnect the power from the ethernet switch/hub and reconnect after 5 minutes, then it works again for a short time. there is no disconnection from the other servers. I have,..... 1.reformatted and rebuilt windows xp pro. 2.tested the switch/hub on another computer, seems ok 3. tested the lan cables. 4. tested the lan access points. yet still i have the trouble. any suggestions would be welcomed. D.Thomas Did you think about HEAT? Access point? You mean Wireless? If no and your device is cheap try replacing it. Hristo http://hristo.no-ip.info "Daz" <thomas@bigpond.net.au> wrote in message news:edr561598tm4vp8otbde4tb0ts7vr26si9@4ax.com... > Hi > can anyone please offer a suggestion to a LAN Problem i have. > Recently my server computer on a 3 access point lan network > has been dropping out after about 10 minutes. > > if i disconnect the power from the ethernet switch/hub > and reconnect after 5 minutes, then it works again for a short time. > there is no disconnection from the other servers. > > I have,..... > > 1.reformatted and rebuilt windows xp pro. > 2.tested the switch/hub on another computer, seems ok > 3. tested the lan cables. > 4. tested the lan access points. > > yet still i have the trouble. > > any su...

debugger problem and other problem
Hi all! I gave it another try to upgarde from 1.0.1 to 1.2.1 from CVS (Rev. 6469). My system: Linux Debian Lenny, kernel 2.6.24. Problems: 1. the classical debugger doesn't show the code. First I thought it could be a color problem, but it isn't. Changing the color doesn't help. You can find a screenshot at http://www.apw-wiegand.de/apwlin/debugger.png. As you can see the debugger finds the code file and shows the line number where it actually is, but doesn't show the code. In 1.0.1 the debugger was functioning. 2. I read several times in the newsgroup that others have the...

Lan problems problems
Hi can anyone please offer a suggestion to a LAN Problem i have. Recently my server computer on a 3 access point lan network has been dropping out after about 10 minutes. if i disconnect the power from the ethernet switch/hub and reconnect after 5 minutes, then it works again for a short time. there is no disconnection from the other servers. I have,..... 1.reformatted and rebuilt windows xp pro. 2.tested the switch/hub on another computer, seems ok 3. tested the lan cables. 4. tested the lan access points. yet still i have the trouble. any suggestions would be welcomed. D.Thomas Di...

Problem with problem section
Hi, I have defined as follows: ------------------------------------------------------------------- \newtheorem{problem}{Problem}[section] --------------------------------------------------------------------------- and I use as: ----------------------------------------------------- \begin{problem} \label{ch6:p2} {\bf {Understanding {\bf XXX} assignment}} Convert the code in problem \ref{ch6:p1} to {\bf XXX} assignment. Fill the table \ref{ch6:p1t}, along with the comments. \end{problem} ------------------------------------------------------------------- What I want is all my figures and table before I start the next problem. With my definitions all my tables and figures goes to some other pages, before next problem section starts. How can I fix this? I don't have this problem in section, subsection and subsubsection. Please help On Nov 16, 1:57=A0pm, Sant <santhosh_h...@yahoo.com> wrote: > Hi, > > I have defined as follows: > ------------------------------------------------------------------- > \newtheorem{problem}{Problem}[section] > -------------------------------------------------------------------------= -- > > and I use as: > > ----------------------------------------------------- > \begin{problem} > \label{ch6:p2} > > {\bf {Understanding {\bf XXX} assignment}} > > Convert the code in problem \ref{ch6:p1} to {\bf XXX} assignment. > Fill the table \ref{ch6:p1t}, along with the comments. > \end{probl...

Windows 7 and Eudora 7.1: problems, problems and problems.
Hi, 3 days ago I have replaced Win XP with Windows 7 and since first day I have problem with Eudora 7.1. My problems are when Eudora downloads emails. I have 6 account, Eudora downloads 3 accunts regularly, then gets stuck on 3� account for 1 minute or more and then it goes again regularly. Therefore I have deleted the 3� account then I have done the download. Eudora downloads 3 account regularly again then it gets stuck again. Always the same problem. Then ..... I have unistalled Eudora and deleted every trace on registry then I have installed it again but now I have the same problems. Perhaps have I to replace Eudora 7 with Eudora 8? I want to cry!!!! Help me please. Thanks a lot. PS. I have replaced beacause it is important for me new mailboxes with old mailboxes and I replaced Eudora.ini. Perhaps is it my problem? AroundTheWorld <AroundTheWorld@DELETEinterfree.it> wrote in news:s4usj5p0otqo5hlr30rsbnibj2t0uh3od1@4ax.com: > Hi, 3 days ago I have replaced Win XP with Windows 7 and since first > day I have problem with Eudora 7.1. > My problems are when Eudora downloads emails. > I have 6 account, Eudora downloads 3 accunts regularly, then gets > stuck on 3� account for 1 minute or more and then it goes again > regularly. > Therefore I have deleted the 3� account then I have done the download. > Eudora downloads 3 account regularly again then it gets stuck again. > Always the same problem. > Then ..... I h...

need to compute this problem having problems with how to start this problem help need urgently
Let   U[0; 2theta] be a uniform random variable from the interval [0; 2theta] and let A  Exp(1) be exponentially distributed with mean 1. Assume  and A independent. Compute the mean mX(t) =E[X(t)] and autocorrelation RX(s; t) = E[X(s)X(t)] of the phase-shifted sinusoid.X(t) = A*  cos(t +theta ): State also if X(t) is Wide Sense Stationary (WSS). plot 10 realisations of X(t) plotR(s-t,0)as a function of s-t "pramod kumar" <pramod.kilu@gmail.com> wrote in message <jpapso$44b$1@newscl01ah.mathworks.com>... > Let   U[0; 2theta] be a uniform random variable from the interval [0; 2theta] and let A  Exp(1) be exponentially distributed with mean 1. Assume  and A independent. Compute the mean mX(t) =E[X(t)] and autocorrelation RX(s; t) = E[X(s)X(t)] of the phase-shifted sinusoid.X(t) = A*  cos(t +theta ): > State also if X(t) is Wide Sense Stationary (WSS). > plot 10 realisations of X(t) > plotR(s-t,0)as a function of s-t So what have you tried? If you have not tried anything, this is a suggestion that you were not paying attention in class. Make an effort. John "pramod kumar" <pramod.kilu@gmail.com> wrote in message <jpapso$44b$1@newscl01ah.mathworks.com>... > Let   U[0; 2theta] be a uniform random variable from the interval [0; 2theta] and let A  Exp(1) be exponentially distributed with mean 1. Assume  and A independent. Compute the mean mX(t) =E[X(t)] and autocorrelation RX(s; t) = E[X(s)X(t)]...

yahoo.com.au mail problems problems problems
Hello, in the last month I encountered big problems to read mail from yahoo.com.au server. There is no chance to connect to e-mail /www based server. Having logged to www.yahoo.com.au mail window doesn't open waiting for an image from au.adserver.yahoo.com server is that server dead, making reading mail completely impossible ? Ping says, that server is unreachable. What can I do to make things better as in previous months ? Ple ...

Purify problem or compiler problem?
Hi, I am using sun's CC (c++ compiler) to compile the follow code: #define __REENTRANT #include <stdio.h> #include <pthread.h> void *one(void *dummy); void two(void); void output(void); int main (int argc, char **argv) { pthread_t tid; pthread_create( &tid, NULL, one, NULL ); pthread_join(tid,NULL); } void *one(void *dummy) { output(); two(); return NULL; } void two(void) { output(); } void output(void) { //char string[16468]; //This one purify likes //char string[16469]={0}; //This and greater makes purify spit BSW's char string[16469]; //This and greater makes purify spit a IPW/R's string[0]='\0'; } This is purify's output: IPW: Invalid pointer write This is occurring while in thread 7: void output() [testmain3.o] void two() [testmain3.o] void*one(void*) [testmain3.o] _thread_start [libthread.so.1] Writing 1 byte to 0x7e5fbbef on the stack of thread 7. Address 0x7e5fbbef is 16473 bytes below frame pointer in function void output(). Thread Summary : 7 threads in existence Thread 0 [main thread] Stack Limit : (0xff3f0000 0xffbf0000), size = 0x800000 Thread 1 Stack Limit : (0x7ef10000 0x7f010000), size = 0x100000 Stack Use : (0x7f00fa30 0x7f00fd54), size = 0x324 Thread 2 Stack Limit : (0x7e652000 0x...

mwm problems and Motif problems
I'm having problems with mwm: I editied a $(HOME)/Mwm file to set some resources, for example the title area background and foreground colors, but they don't have effect. I would also like to prevent the user from moving the application's main window by actig on the title bar. Another thing I would like to set is the font used by my application: for achieving this, I edited the resource file for my application, located in X11R6/.../app-defaults/<appl_class_name> writing in it: *Font : 8x13 I get the warning message: Warning: Cannot convert string "8x...

AUTH problems + Eudora Problem
hello 2 problems first thanks for help ! a.) in my log are this entrys >Sep 29 18:41:44 mail sendmail[19032]: >i8TGffmK019021: SYSERR(root): hash >map >"authinfo": missing map file /etc/mail/authinfo.db: No such >file or directo Does not sendmail makes authinfo.db automatical ? is it cause of FEATURE(`authinfo')dnl in the .mc? b.) when i auth with outlook all is fine, when i try to auth over eudora there comes a failure that i need to auth. i use this .mc (all works fine auth with outlook in testing too) divert(0)dnl VERSIONID(`$Id: generic-linux.mc,v 8.1 1...

Cable problem or card problem
hi i have a tekram scsi card, i have connected my hd on her 68-Pin Wide SCSI Internal that work fine. this week i received a adaptect 39160. i have connected my hd with the same cable of my other scsi card, under linux i get some message: Dec 12 16:11:15 linux kernel: SCSI error : <1 0 0 0> return code = 0x6000000 Dec 12 16:11:15 linux kernel: end_request: I/O error, dev sda, sector 19847 Dec 12 16:11:15 linux kernel: Incorrect number of segments after building list Dec 12 16:11:15 linux kernel: counted 9, received 3 Dec 12 16:11:15 linux kernel: req nr_sec 1016, cur_nr_sec 8 Dec 12 1...

sna problem + arp problems
hello, i'm have tow problems i'm working on F50 aix 4.3.3.11 1) when i'm using ping command my arp table not be update. 2) on sna ver 6 i'm get this error : start_ls command failed : primary_rc = LS_FAILURE, secondary_rc = PARTNER_NOT_FOUND on /var/sna/sna.err the i've get this error : GDLC rejected call to start LS Error = cannot find the remote name (-920) thank ariec arieco@clalit.org.il wrote: > i'm working on F50 aix 4.3.3.11 > > 1) when i'm using ping command my arp table not be update. Do you get ICMP replies to your pings? Do you ping I...

Printer problem or application problem?
I use an HP Deskjet 5550. My favorite word processing application is Word Perfect (I use WP Office 2002 Professional with the latest service pack.) I am unable to format an envelope size 6 3/4. I get a message saying the printer does not support that size, and do I want to use the nearest close approximate (DL), That is an acceptable but not convenient alternative. However, using Microsoft Word, I am able to format and print size 6 3/4 envelopes without difficulty. I have had extensive conversations on a Corel users forum about this, but nobody seems to come up with a solution. Is this a problem with the printer, or is this a problem with Word Perfect? On Thu, 3 Jul 2003 17:15:45 -0400, "Gordon Nelson" <banovce@aaahawk.com> wrote: >I use an HP Deskjet 5550. My favorite word processing application is Word >Perfect (I use WP Office 2002 Professional with the latest service pack.) > >I am unable to format an envelope size 6 3/4. I get a message saying the >printer does not support that size, and do I want to use the nearest close >approximate (DL), That is an acceptable but not convenient alternative. > >However, using Microsoft Word, I am able to format and print size 6 3/4 >envelopes without difficulty. > >I have had extensive conversations on a Corel users forum about this, but >nobody seems to come up with a solution. > >Is this a problem with the printer, or is this a problem w...

ReFresh problem or target problem
I have CGI program which the program used to edit the information about the question from the database. Once, I update the question, if I press F5 or Refresh, it will load to the default frame. I have divided the frame into 3 main parts, the top with the information about the login name, and the left about the menu for user to nevigate thought (Other link to call cgi files, and this frame will load itself to the right frame), and the right frame to display information. I also set the default frame for the right frame as well. Anyone knows how to make my current cgi file when User click Refr...

Purify problem or compiler problem?
Hi, I am using sun's CC (c++ compiler) to compile the follow code: #define __REENTRANT #include <stdio.h> #include <pthread.h> void *one(void *dummy); void two(void); void output(void); int main (int argc, char **argv) { pthread_t tid; pthread_create( &tid, NULL, one, NULL ); pthread_join(tid,NULL); } void *one(void *dummy) { output(); two(); return NULL; } void two(void) { output(); } void output(void) { //char string[16468]; //This one purify likes //char string[16469]={0}; //This and greater makes purify spit BSW's char string[16469]; //This and greater makes purify spit a IPW/R's string[0]='\0'; } This is purify's output: IPW: Invalid pointer write This is occurring while in thread 7: void output() [testmain3.o] void two() [testmain3.o] void*one(void*) [testmain3.o] _thread_start [libthread.so.1] Writing 1 byte to 0x7e5fbbef on the stack of thread 7. Address 0x7e5fbbef is 16473 bytes below frame pointer in function void output(). Thread Summary : 7 threads in existence Thread 0 [main thread] Stack Limit : (0xff3f0000 0xffbf0000), size = 0x800000 Thread 1 Stack Limit : (0x7ef10000 0x7f010000), size = 0x100000 Stack Use : (0x7f00fa30 0x7f00fd54), size = 0x...

Decision Problem and Optimization Problem
Two questions occurred to me when I studied materials related to Church-Turing thesis. A book say ALL problems are classfied into decision problems or optimization problems. Is it right? If so, how can we prove it? And an optimization problem can be solved by binary searching between a lower bound and a upper bound, if we can solve the corresponding decision problem. But is it ALWAYS possible to know the boundaries? Thanks. Deokhwan Kim wrote: > Two questions occurred to me when I studied materials related to > Church-Turing thesis. > > A book say ALL problems are classfied in...

Problem in solving a problem by matlab.
Hello Everybody, I am having a problem in back propagation network. It is not a direct one to use sofwares like matlab for simulation. The problem is briefly described as follows. I want to specify the number of interconnections in the hidden layer or between the hidden layers. Can this possible using Matlab? Also I want to share the weights between two sets of hidden layers how to do that in Matlab? Please suggest me any other GUI softwares that can solve both the above problems or give me suggestions or atleast the posibility of doing this in Matlab(any...

db problem BIG PROBLEM
We are having a problem on our database, DB2 running on 0s/400 v5r1 and SAP 4.6b. We have a database table on Sap that isn't aligned with the table on the db, this was caused by a breakdown during a transportation. At this moment the table on Sap have one field more than the fields list that we see into db2 from as400. Someone can help us? thanks to all alberto How about running an ALTER TABLE and adding the missing field to the DB2 file? Sam "Alberto" <albe.net@caleffi.it> wrote in message news:1160089901.442664.271060@k70g2000cwa.googlegroups.com... > We are h...

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