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I keep getting those, mostly at times that I am either asleep or away from any computer or device. Is it someone trying to get into my account? I checked the e-mail's details and they seem legit. I tried logging off and attempting to simulate someone hijacking the "I forgot my password", but instead I got a different e-mail with a 6-character code. I don't really care that much about my security being compromised (overkill 128-char random pass + two-factor auth), it's just relatively annoying. Screenshots: http://i.imgur.com/5xewZEP.jpg & http://i.imgur.com/4nNTsZQ.jpg Matt714 ( talk) 01:37, 17 August 2015 (UTC)
Yeah, I also thought it was a bot. Thanks for your input. Matt714 ( talk) 04:17, 19 August 2015 (UTC)
In my R.V, I have wired in a USB socket. Is there an adapter that can convert the usb to a plug that can go in my notebooks socket. Bearing in mind the rv socket is rated 5amps max. — Preceding unsigned comment added by 80.195.27.47 ( talk) 13:08, 17 August 2015 (UTC)
Due to a discussion in the German Wikipedia, i'd like to ask if anyone who uses the following public transport lines could note the IP he gets when using the Wifi there:
I'd be grateful if someone could post here IPs the Wifis there have. -- 62.109.35.148 ( talk) 17:30, 17 August 2015 (UTC)
Hi Guys, I stupidly asked Microsoft to tell me when Windows 10 was ready to be downloaded for me to upgrade. Since then I have learned a bit about Windows 10 and really do not want to upgrade. Unfortunately, I now can't see how to get rid of the upgrade icon in my system tray, nor can I see how to stop the constant reminders that I haven't upgraded. Can anyone tell me how to get rid of all that please? I am currently running Windows 7. Thank you Gurumaister ( talk) 17:55, 17 August 2015 (UTC)
Thank you Nil Einne. I should have tried that but I think when I need expert advice, I tend to come straight here. Forgive me if I wasted your time but I am also very grateful. Gurumaister ( talk) 19:09, 17 August 2015 (UTC)
I have a further question about the halting problem. This has been bugging my mind for years.
Suppose we have a hypothetical function int halts(char *program)
which returns 1 if the program halts and 0 if it doesn't.
Now the reason given why such a function is impossible is that if we make another function:
void halts2(char *program) { while (halts(program)); }
Then halts2
, given itself as input, is a program that halts when it doesn't halt and doesn't halt when it halts, which is impossible. This far I understand.
But my question is, halts2
is a function taking an input. You can't just run halts2
, you have to give it some program as input. So is halts2
exactly the same program when it's run given itself as input and when given as input to itself?
JIP |
Talk 18:28, 17 August 2015 (UTC)
halts2
incorrectly or is this precisely why a function analysing whether another function halts is impossible?
JIP |
Talk 18:55, 17 August 2015 (UTC)
halts
on the given program and do the opposite". The
recursion theorem says you can do this, but I can never remember exactly how, assuming I ever in fact knew. Update: That link is a disambig — the article on the one I mean is at
Kleene's recursion theorem. halts2
is going to be a sort of a quine, but it doesn't just print its own source code and be done with it. Instead, it prints its own source code, feeds it in to halts
, and based on the output, decides whether to halt or go into an infinite loop (doing the opposite of whatever halts
predicts. --
Trovatore (
talk) 21:57, 17 August 2015 (UTC)halts2
is not calling halts
as a library function. It has the source code for halts
inline. So when it prints its own source code, it's necessarily also printing the source code for halts
as part of that. That's why you need a different halts2
for each proposed implementation of halts
. --
Trovatore (
talk) 22:00, 17 August 2015 (UTC)extern int halts(char *program, char *argument);
void halts2(char *argument) { while (halts(argument, argument)); }
halts2("void halts2(char *argument) { while (halts(argument, argument)); }");
extern int halts(char *program);
void halts2() { char p[999], s[] = "void halts2() { char p[999], s[] = %c%s%c; sprintf(p, s, 34, s, 34); while (halts(p)); }"; sprintf(p, s, 34, s, 34); while (halts(p)); }
halts
to take two arguments and then calling halts2
with its own source code as both arguments to halts
) is the easiest and therefore the best way to go. I still have to think this through. I know intuitively that the halting problem argument is true, that such a program is impossible, I just have to get my head around the details.
JIP |
Talk 18:42, 18 August 2015 (UTC)
halts
as an "extern" function. It can't be a library function. halts2
actually has to depend on the source code of halts
. If it didn't, you could "reverse the quantifiers" in my discussion with SteveBaker above, and you can't, as I showed there. Also, if you could refute the existence of a halting decider without assuming anything about the source code (such as, there is such a thing as its source code), then you could refute the existence of an
oracle machine — and if that could be done so easily, you can be sure it would have been.halts
is treated as a library function. --
Trovatore (
talk) 04:35, 19 August 2015 (UTC)I'm getting a backlog of a lot of things to read online, so I think it's better to multitask listening to an article with anything else that I'd want to do more.
Now the TTS programs need to be free, and I don't care if it has ads in exchange for being free. So what are some good ones that are updated on a regular basis and does a pretty good job at what it's supposed to do?
And to anyone who has used them, which of them left you the most satisfied? Thanks. -- 66.87.73.78 ( talk) 22:15, 17 August 2015 (UTC)
Computing desk | ||
---|---|---|
< August 16 | << Jul | August | Sep >> | August 18 > |
Welcome to the Wikipedia Computing Reference Desk Archives |
---|
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages. |
I keep getting those, mostly at times that I am either asleep or away from any computer or device. Is it someone trying to get into my account? I checked the e-mail's details and they seem legit. I tried logging off and attempting to simulate someone hijacking the "I forgot my password", but instead I got a different e-mail with a 6-character code. I don't really care that much about my security being compromised (overkill 128-char random pass + two-factor auth), it's just relatively annoying. Screenshots: http://i.imgur.com/5xewZEP.jpg & http://i.imgur.com/4nNTsZQ.jpg Matt714 ( talk) 01:37, 17 August 2015 (UTC)
Yeah, I also thought it was a bot. Thanks for your input. Matt714 ( talk) 04:17, 19 August 2015 (UTC)
In my R.V, I have wired in a USB socket. Is there an adapter that can convert the usb to a plug that can go in my notebooks socket. Bearing in mind the rv socket is rated 5amps max. — Preceding unsigned comment added by 80.195.27.47 ( talk) 13:08, 17 August 2015 (UTC)
Due to a discussion in the German Wikipedia, i'd like to ask if anyone who uses the following public transport lines could note the IP he gets when using the Wifi there:
I'd be grateful if someone could post here IPs the Wifis there have. -- 62.109.35.148 ( talk) 17:30, 17 August 2015 (UTC)
Hi Guys, I stupidly asked Microsoft to tell me when Windows 10 was ready to be downloaded for me to upgrade. Since then I have learned a bit about Windows 10 and really do not want to upgrade. Unfortunately, I now can't see how to get rid of the upgrade icon in my system tray, nor can I see how to stop the constant reminders that I haven't upgraded. Can anyone tell me how to get rid of all that please? I am currently running Windows 7. Thank you Gurumaister ( talk) 17:55, 17 August 2015 (UTC)
Thank you Nil Einne. I should have tried that but I think when I need expert advice, I tend to come straight here. Forgive me if I wasted your time but I am also very grateful. Gurumaister ( talk) 19:09, 17 August 2015 (UTC)
I have a further question about the halting problem. This has been bugging my mind for years.
Suppose we have a hypothetical function int halts(char *program)
which returns 1 if the program halts and 0 if it doesn't.
Now the reason given why such a function is impossible is that if we make another function:
void halts2(char *program) { while (halts(program)); }
Then halts2
, given itself as input, is a program that halts when it doesn't halt and doesn't halt when it halts, which is impossible. This far I understand.
But my question is, halts2
is a function taking an input. You can't just run halts2
, you have to give it some program as input. So is halts2
exactly the same program when it's run given itself as input and when given as input to itself?
JIP |
Talk 18:28, 17 August 2015 (UTC)
halts2
incorrectly or is this precisely why a function analysing whether another function halts is impossible?
JIP |
Talk 18:55, 17 August 2015 (UTC)
halts
on the given program and do the opposite". The
recursion theorem says you can do this, but I can never remember exactly how, assuming I ever in fact knew. Update: That link is a disambig — the article on the one I mean is at
Kleene's recursion theorem. halts2
is going to be a sort of a quine, but it doesn't just print its own source code and be done with it. Instead, it prints its own source code, feeds it in to halts
, and based on the output, decides whether to halt or go into an infinite loop (doing the opposite of whatever halts
predicts. --
Trovatore (
talk) 21:57, 17 August 2015 (UTC)halts2
is not calling halts
as a library function. It has the source code for halts
inline. So when it prints its own source code, it's necessarily also printing the source code for halts
as part of that. That's why you need a different halts2
for each proposed implementation of halts
. --
Trovatore (
talk) 22:00, 17 August 2015 (UTC)extern int halts(char *program, char *argument);
void halts2(char *argument) { while (halts(argument, argument)); }
halts2("void halts2(char *argument) { while (halts(argument, argument)); }");
extern int halts(char *program);
void halts2() { char p[999], s[] = "void halts2() { char p[999], s[] = %c%s%c; sprintf(p, s, 34, s, 34); while (halts(p)); }"; sprintf(p, s, 34, s, 34); while (halts(p)); }
halts
to take two arguments and then calling halts2
with its own source code as both arguments to halts
) is the easiest and therefore the best way to go. I still have to think this through. I know intuitively that the halting problem argument is true, that such a program is impossible, I just have to get my head around the details.
JIP |
Talk 18:42, 18 August 2015 (UTC)
halts
as an "extern" function. It can't be a library function. halts2
actually has to depend on the source code of halts
. If it didn't, you could "reverse the quantifiers" in my discussion with SteveBaker above, and you can't, as I showed there. Also, if you could refute the existence of a halting decider without assuming anything about the source code (such as, there is such a thing as its source code), then you could refute the existence of an
oracle machine — and if that could be done so easily, you can be sure it would have been.halts
is treated as a library function. --
Trovatore (
talk) 04:35, 19 August 2015 (UTC)I'm getting a backlog of a lot of things to read online, so I think it's better to multitask listening to an article with anything else that I'd want to do more.
Now the TTS programs need to be free, and I don't care if it has ads in exchange for being free. So what are some good ones that are updated on a regular basis and does a pretty good job at what it's supposed to do?
And to anyone who has used them, which of them left you the most satisfied? Thanks. -- 66.87.73.78 ( talk) 22:15, 17 August 2015 (UTC)