Can I compile Java source (which uses Swing and other libraries) into exe so that it does not need JavaSE?

Is it posible to compile Java source (which uses libraries like Swing etc) in an exe file, so the user doesn't need to install JavaSE?  I am looking for some way to bundle a mini-JRE and the .jar in a single file (exe) or some way to compile everything (source and libraries) into native code.  PS: Obviously I don't care about cross-compat for that program.


How long until a bronze tag badge shows up?

If you check my  you will notice that I finally scored over 100 points on the C tag, and that was a couple of hours ago.   I understand that is the only requirement to earn a bronze C tag badge. Am I wrong?   If not, how long do I have to wait to be awarded with the badge?  Thank you.


"Save and copy changes to all public communities" does not include the stackexchange.com profile

How do I edit my Network Profile?  Edit: "Save and copy changes to all public communities" does not work for the Network Profile.  This looks like a bug. Is it supposed to not include stackexchange.com, Especially since meta.stackexchange.com gets updated?  This is currently the only way to edit update it:


Sets containing itself and axiom of regularity

I have seen all the available answers to this question here and I am still in doubt. I know that any set x containing a single element, ie itself, can easily shown to be non-existent. But, how do we go about proving that the following is not possible? - x = {y, x} - were y is another entity completely disjoint from x. Say, y = 1.


combustion vs biological oxidation of glucose

I am a high school student and I am a little confused in cellular respiration, To represent respiration many biology text books just writes, C6H12O6 + 6 O2 --> 6 CO2 + 6 H2O But in actual biological oxidation of glucose 10 molecules of water are release and not 6, so where does the 4 molecule go? please explain this in simple language, because I am at the high school level .I, don't know much about this, so please keep your answer on to the point.


How to get posts published between a date and today?

Is it a way to get posts published between a date and today with query_posts() ?  Example : All posts published since 2012-04-01  Thanks  EDIT :   How to add the filter date on this Query Posts ?  query_posts( array(       array('post'),     'tax_query' => array(         array(             'taxonomy' => 'post_format',             'field' => 'slug',             'terms' => array('post-format-image')         )     ),     'cat' => '-173',     'post_status' => 'publish' ) );


Why there is electromagnetic resistivity $\approx 377\Omega$ in vacuum?

I cant understand that. If there isn't a material that makes it hard to pass, why there is a  in vacuum?


Add increase/decrease tab indent buttons to the editor toolbar

These should work by adding spaces or removing spaces from the beginning of the current line or every line between the start and end of a text selection (inclusive).  (edited this question to supplement )


I looked at a chat where people said there were about 730ish steps along the way, but I was wondering if they counted the steps in each row as one or counted all individual steps, because in some cases there won't be one step per stair, there can be 2-4 steps where the one whole stair is. Can anyone clarify how many steps there are as every single stone slab on it's own as a step?


Someone told me that "time" is us seeing 3D slices of 4D spacetime, and that an object in spacetime is a 4D object which is tenseless and contains the past present and future of that object. I don't know much about physics, so is this a good explanation?


How can I block the traffic outside the VPN, even if the VPN is down?

I would like to direct all the traffic through my VPN connection on my Android based phone (HTC Desire). The VPN works great, but problem is that when the VPN disconnects, the traffic is redirected through my regular internet, something I don't want to happen. How can I block the traffic outside the VPN?


The status of "Editor assigned" did not change for 4 weeks

I submitted the manuscript to a Springer medical journal. One month later, major revision was suggested. Then I re-submitted the revised form. One day later, the status changed as "editor assigned". Finally, this status did not change for 4 weeks. What does it mean? Has the assessment started yet?  Thanks..


What does "period" mean when someone says "Sth... Period"?

I often hear US citizens say something like this:     <Some phrases>. Period.   What does period mean when it appears in a sentence by itself in this type of situation?


Replace accept rate with citizenship level

I see that accept rate has now been . I think this is not a great solution for . Take it away waffles!     On one hand accept rate bothers me a lot, it is a one-dimensional metric that does not really give me enough information about how upstanding a user is in the community. It is used frequently to bully users and leaves a horrible taste.      On the other hand, introducing accept rates heavily increased the amount of accepted answers in the system. Which in turn helps close loops and motivate the community.            When we introduced the accept rate stuff we were careful not to add too much of a value statement. On hover we do not say "horrible user, never accepts answers".      Going forward I would much prefer that we retired accept rate in favor of a more general metric that covers a variety of "citizenship" metrics that do not result in rep.         Does the user vote?   Does the user accept answers?   Does the user answer questions?   Does the user edit or suggest edits on questions?   Does the user flag stuff?         I don't know, perhaps we should go the other way and show a tagline of honor for the top N percent of users.   Rather than removing accept rate, I propose replacing it with a citizenship percentage or level, based on the above criteria. This would be a powerful motivator for better sites, and gives much more useful context for the question.  It is not that displaying accept rate was bad, so much as incomplete. I always had plans to circle back and improve it to be a citizenship level.  Displaying this metric on questions might help participants think of the game at a bit higher level. What is more useful to the longer term health of a community: a single OK question, or an engaged community member who assists and participates — as a citizen, not just another drive by hit and run?


While answering the question  it occurred to me that time would run more slowly at the equator than at the North Pole, because the surface of the Earth is moving at about 464 m/s compared to the North Pole. The difference should be given by:  $$ \frac{1}{\gamma} \approx 1 - \frac{1}{2}\frac{v^2}{c^2} $$  and at $v = 464\ \mathrm{m/s}$ we get:  $$ \frac{1}{\gamma} \approx 1 - 1.2 \times 10^{-12} $$  This is a tiny difference – about 4 days over the 13.7 billion year lifetime of the universe – but  the accuracy of current atomic clocks is about $1$ part in $10^{14}$, so the difference should be measurable. However, I have never heard of any measurements of the difference. Is there a flaw in my reasoning or have I simply not been reading the right journals?


Can these two limits be used to directly check the twice differentiability of a function?

Can the equality of these two be used as a second-order differentiability check?:  $$\lim_{h\downarrow 0}\frac{f(x+2h)-2f(x+h)+f(x)}{h^2}$$ And, $$\lim_{h\downarrow 0}\frac{f(x-2h)-2f(x-h)+f(x)}{h^2}$$  I think that just like when the limits $\lim\limits_{h\downarrow 0}\frac{f(x+h)-f(x)}{h}$ and $\lim\limits_{h\downarrow 0}\frac{f(x-h)-f(x)}{-h}$ are equal, then it means that the function is differentiable, the equality of these two limits should mean that the function  is twice differentiable.  Please note that $h$ itself is assumed to be positive in the limits.


Based on an answer on  in the bibliography with biblatex, a question arose on the possible use of the \footcite command with the provided new style. This \footcite command seems to be a good compromise for rather long scripts where you do not want to disturb the main text with things like [Author Year] (authoryear style) or when you want to provide more information than [] (numeric style). So, the question is how to create a personal biblatex style based on the numeric style that would provide information in a footnote when \footcite is used. Minimal information here should be thought for each case @article, @book, @phdthesis, @inproceedings but would just indicate contracted author names, title, year... The link to the main reference in the bibliography section should be added as well in the footnote.


Can someone help me figure out what resistor to wire to this LED for maximum brightness?

I know that you're supposed to wire a resistor with an LED to stop it from being damaged, but I don't know how resistant a resistor to put in. My input voltage will be from a 3.7V Li-Ion battery. The LED says it's 12w, and the LED is red (no info on the led besides that). It has a heatsink. What resistor should I wire up to prevent the LED from being damaged while maximizing it's brightness? If this isn't enough info, let me know what else I need to answer this question. The LED was running fine connected to a 6v (1.5V x 4 aaa batteries) with a resistor in series that was heatshrinked and couldn't be read once I took it off.


How to delete all of the posts made by one user to a Facebook group?

I am running a Facebook group and we do not accept spam posts. Sometimes, a spammer will post 100+ status updates in just 1 minute. It is very difficult to remove all (100+) posts one by one.  Is there any way that I can delete all of this user's posts very fast from within Facebook?


Is there a way from within windows to identify which BIOS is in the machine?

I'm wondering if there's a way to retrieve information on the BIOS from within Windows 7 without rebooting and going into the BIOS.  I've checked Control Panel\System and Security\System and Device Manager.  A registry key or a built-in GUI or commandline tool is fine, I would also settle for something I have to download if there is no included way.  The more info it can get the better. For instance  American Megatrends / Phoenix / Award plus version numbers, dates, whatever.  UPDATE  I have now been able to find some settings in the registry...   HKEY_LOCAL_MACHINE\HARDWARE\DESCRIPTION\System\SystemBiosDate HKEY_LOCAL_MACHINE\HARDWARE\DESCRIPTION\System\SystemBiosVersion HKEY_LOCAL_MACHINE\HARDWARE\DESCRIPTION\System\VideoBiosDate HKEY_LOCAL_MACHINE\HARDWARE\DESCRIPTION\System\VideoBiosVersion   Is there any more detailed information that can also be retrieved from within the OS?


Are acceleration and velocity simultaneous?

I would think yes because, if a rope tied to a swinging rock breaks, the rock flies off in the direction that is perpendicular to the direction of the last instant of the acceleration. The acceleration at the last instant it existed determined the velocity direction of the rock. So acceleration over time changes a velocity’s speed and or direction but at any instant the velocity is determined by the acceleration at that instant. Correct?


What would happen if a muggle went inside the Diagon Alley? Assuming they could

I don´t know if the canon specifies whether a muggle can or can´t enter Diagon Alley , someone asked if Diagon Alley can be accessed through the sky, and apparently it´s possible.   What would happen then if a muggle entered Diagon Alley?


This is probably very basic, but I am having trouble navigating nested lists in python 3.  list1 = [[0]*3]*3 list1[0][1] = 1 print(list1)   Produces the output  [[0, 1, 0], [0, 1, 0], [0, 1, 0]]   when I expected the output to be  [[0, 1, 0], [0, 0, 0], [0, 0, 0]]   Why is this happening?


Do you know of some font which has an ant as a character?  (I need it in a document I'm preparing in plain tex that is to be processed by pdftex.)


How do I only use the Intel HD 3000 card on an HP dv6?

I have a HP dv6 6195sp, the Pc have a AMD Radeon™ HD 6770M GDDR5 and Intel HD 3000. After installation ubuntu only use the AMD graphic card, how to install and use only the intel graphic card ?


I'm trying to create a archive list with only my "normal" post format articles (not link, aside, quote, etc formats).  How would I implement has_post_format( 'standard' ), or something similar, into the code below?  I haven't been able to find a query for get_posts that only requests specific format types.  <?php         // Get the posts     $myposts = get_posts('numberposts=-1&orderby=post_date&order=DESC');      ?>  <?php foreach($myposts as $post) : ?>     <?php         // Setup the post variables     setup_postdata($post);      $year = mysql2date('Y', $post->post_date);     $month = mysql2date('n', $post->post_date);     $day = mysql2date('j', $post->post_date);     ?>
              <a href="<?php the_permalink(); ?>"><?php the_title(); ?>          &nbsp;&nbsp;&nbsp;              <?php the_time('j F Y'); ?>
  <?php endforeach; ?>   My php skills are at the beginner level at best, so any help would be much appreciated.


presentation title out of range using Boadilla theme

I'm trying to prepare a presentation in LaTeX using Beamer. I'm using the Boadilla theme. unfortunately I have troubles in the title of the presentation because it is too small.  I tried to enlarge it using "bold" but unfortunately the title in  the lower bar of the font goes out of range.   Can anyone help me please?


Java error Exception in thread "Thread-2" java.lang.NullPointerException

I am a hobbyist Just starting with java about 5 months ago. I created this project for just fun. Coming here was my last resort, normally I can solve these problems on my own. I keep getting this error occasionally when I move my player.  Exception in thread "Thread-2" java.lang.NullPointerException at java.util.LinkedList.node(Unknown Source) at java.util.LinkedList.get(Unknown Source) at Handler.render(Handler.java:55) at Game.render(Game.java:136) at Game.run(Game.java:76) at java.lang.Thread.run(Unknown Source)    I have plenty of other problems with this project this is only my second game I've attempted to make on my own If you could help With any other errors you see that whould be very helpful.(Have never Used Stack before)


We have a table that has 7 columns. We are trying to get to fit the page, but it will not do so. Do you have any suggestions as to how we might get this to fit either horizontally or vertical.     \begin{table}[] \centering \caption{My caption} \label{my-label} \begin{tabular}{|l|l|l|l|l|l|ll}     \cline{1-6}     \textbf{Communication task}  & \textbf{Audience}                                             & \textbf{Objectives/ Goals}                                                                                & \textbf{Tools/ Resources Needed}                                                               & \textbf{Method of communication}                              & \textbf{Outcome}                                                                             &  &  \\ \cline{1-6}     Initial Group Meeting        & Project group                                                  & Exchange contact details\\and establish group \\weaknesses and strengths                                                          & Notes                                                                                & Face-to-face                                                  & Group chat created                                                                           &  &  \\ \cline{1-6}     Arrange meeting with sponsor & Communications leader and Sponsor                              & Establish meeting time                                                                                &                                                                                & Email                                                         & Meeting arranged with sponsor                                  &  &  \\ \cline{1-6}     Group meeting                & Project group                                                  & \begin{tabular}[c]{@{}l@{}}Read project brief\\ Discuss questions to ask sponsor\end{tabular}                                  & \begin{tabular}[c]{@{}l@{}}Project brief\\ Notes\end{tabular}                                  & Face-to-face                                                  & List of questions to ask sponsor                                                             &  &  \\ \cline{1-6}     Meeting with sponsor         & \begin{tabular}[c]{@{}l@{}}Project team\\ Sponsor\end{tabular} & Clarify the project requirements                                                                                & \begin{tabular}[c]{@{}l@{}}Audio recording\\ \\ OneDrive\end{tabular}                          & \begin{tabular}[c]{@{}l@{}}Email\\ Face-to-face\end{tabular}  & Established project requirements                                                             &  &  \\ \cline{1-6}     Team meeting                 & Project team                                                   & \begin{tabular}[c]{@{}l@{}}Division of tasks for formative coursework\\ Test blackboard collaboration application\end{tabular} & \begin{tabular}[c]{@{}l@{}}Coursework brief\\ OneDrive\\ Blackboard collaboration\end{tabular} & \begin{tabular}[c]{@{}l@{}}Face-to-face\\ Webcam\end{tabular} & \begin{tabular}[c]{@{}l@{}}Tasks allocated \\ Established how to work BB collab\end{tabular} &  &  \\ \cline{1-6}     &                                                                &                                                                                &                                                                                &                                                               &                                                                                &  &  \\ \cline{1-6} \end{tabular} \end{table}


I'm install OpenJDK Java on my Ubuntu 12.04 desktop using the following command:  sudo apt-get install openjdk-7-jdk   But I keep having java not found:  The program 'java' can be found in the following packages:  * default-jre  * gcj-4.6-jre-headless  * openjdk-6-jre-headless  * gcj-4.5-jre-headless  * openjdk-7-jre-headless Try: sudo apt-get install <selected package>   What's the reason here? I tried reinstall, even deleting /usr/lib/jvm but it still doesn't work.  There is no java in /usr/lib/jvm/java-1.7.0-openjdk-amd64/bin, only javac and other things. Also when I run javac, this is the error:  javadoc: error while loading shared libraries: libjli.so: cannot open shared object file: No such file or directory


Press-and-hold or Long-Press Gestures: Unintuitive?

Often, I find people struggle with the usage of press-and-hold gestures on mobile/web platforms. The mere thought of having a user press on a defined object and hold for an arbitrary amount of time before the product reacts seems overtly complicated and unobtrusive. My questions are:   For what use cases do press-and-hold gestures best fit? Have there been published studies with regards to press-and-hold gesture intuition? Are there more viable alternatives to this system?


Astronauts make emergency landing on a planet that is a storage facility for alien stuff, including weapons

I'm looking for this short story - Astronauts make an emergency landing on a spiky/needle-like surface planet which turns out to be a storage facility for alien stuff. Astronaut almost starves to death, he can't figure which of the alien stuff is edible or poisonous. Some items he opens turns out to be alien weapons. That's all I remember.   It was in a SF anthology with another short story - How's the Night Life on Cissalda by Harlan Ellison


A person randomly chooses a coin with probability 0.5: Tossing coin 1 yields a head with a probability P(X1=H)=.3 (and tail with P(X1=T)=.7). Tossing coin 2 yields a head with a probability P(X2=H)=.6 (and tail with P(X2=T)=.4). You earn 1 dollar if you correctly guessed the coin and 0 dollars otherwise. Design the optimum decision rule and estimate your average earning.  Can anybody explain me ,how should i go about solving this problem?


Setting sublime text as default for all Java files

Incidentally, I have RStudio & R installed on my laptop. So I don't know why but when I double-click on .java files, they open by default in RStudio.  Every time I have to right-click and choose Sublime/Gedit as preferred choice to open these files in a proper text-editor. Can someone guide me on how to set Sublime as default for .java files(so that I can open them in Sublime with a simple double-click)?  UPDATED REQUEST: It would be much helpful if a way of doing this using terminal (or a way without using the Unity interface).  My question is partially different from  in that I preferably need a terminal-using way.


Combinatorial proof of $\sum^{n}_{i=1}\binom{n}{i}i=n2^{n-1}$.

Prove that   $$\sum^{n}_{i=1}\binom{n}{i}i=n2^{n-1}$$   I can't find counting interpretations for either of the sides. A hint of "if $S$ is a subset of $\{1, . . . , n\}$ and $S^\prime$ is its complement then $|S| + |S^\prime| = n$" was also given, but I still don't know how to begin.


Wanted to count total attemps by day awk

im trying to count the number of ocurrences for a list in awk, actually im able to get it for each user the total attemps, but i wanted total attemps by day. I have a txt file something like: ID, Event, Date, Type, Message, API, User, Protocol, Attemps  1, ERROR, 30-NOV-20, 4, TEXT, 2, user1, GUI, 9  i used below awk to count total attemps: awk 'FNR == NR {count[$(NF-3)]++; next} {print $(NF-3), $3 "\t" count[$(NF-3)]}' file file  Can someone help me? Expected output: USER  ATTEMPS DATE user1 3       20-NOV-2020 user1 6       22-NOV-2020 user2 2       01-DEC-2020 user3 4       12-NOV-2020 user3 19      18-NOV-2020


My sock account tried to add a comment, which it obviously can't since it doesn't have much reputation (yet).  The 'error notification' lacks a nice font and is positioned too far to the right:        The missing layout is also a problem with the same tool tips on various places, like the log in screen.  Can this be fixed? My sock says pretty please.


I have a string as follows:  "[Monday, Tuesday]"   I want to convert this string to a list of enums of type "Day". My "Day" enum is as follows:  public enum Day {     Monday,Tuesday; }   I obtained my input string by calling toString() on a List of "Day"s. As follows:  List<Day> days = new ArrayList<Day>(); days.add(Day.Monday); days.add(Day.Tuesday);  String input = days.toString();   I know that I can parse the input string by commas and brackets. But, is there any efficient way to do this?  To repeat, I want to covert string to a list of enums.  ** EDIT **  Question is not just about converting String to enum and vice versa. It involves lists and string parsing.


the scope of arguments declared in functions in javascript

A question about scope which I couldn't find online. If you would have a piece of code like:  Function foo(myVar) { return myVar + 1 }   Would myVar be bounded to the scope of foo? Thank you for your time.  Edit: this is different from a question about scopes of variables in arguments because I wasn't sure if that would apply to arguments, since they weren't stated with var before them.


Can anybody help me out with solving this mathematical proof?     Prove the statement “There is no smallest rational number greater than   2” by contradiction.   Contradiction: There is a smallest rational number greater than 2.  I know the above is false because the smallest rational number greater than 2 is a fraction of a decimal 2.00…01 as it gets closer and closer to 2 (by adding more decimal places). Since you can get infinitely closer and closer to 2 there is no exact “smallest rational number”.  However, I'm not sure how to officially prove it.  Thanks in advance!


What is the difference between SATA and eSATA?

Is the following correct?  eSATA is the same as SATA, except that the cable plug has a slightly different shape, but as far as the electrical signal goes, it's the exact same thing. In theory, if you had a powered-on HDD enclosure with an eSATA port and a cable with an eSATA plug on one end and a SATA plug on the other end, you could connect this device directly to a SATA socket on the motherboard of a powered-on PC and it would work.   (Note: This is theoretical; I don't propose mucking about inside a powered-on PC.)


How to use hook_node_presave to change field's value

Basically, I want to put first name & surname together into $node->field_par_contact_name  But it gives me warning. (See below)   function partnership_node_presave($node) {   if($node->type == 'partnership') {     $first_name = $node->field_par_contact_first_name['und'][0]['name'];     $surname = $node->field_par_contact_surname['und'][0]['name'];      // https://drupal.org/project/field_hidden     // Hidden variable     $node->field_par_contact_name['und'][0]['value'] = $first_name. ' '. $surname;      // Warning after save: array_flip(): Can only flip STRING and INTEGER values! in DrupalDefaultEntityController->load() (line 173 of .../drupal-7.23/includes/entity.inc   } }   Updated, please see image:


Using two wireless NICs at the same time on Windows 10 desktop PC

I have read similar questions in the past (i.e.  and ), however they don't address my question adequately.  I am attempting to understand if I can use 2 separate wireless cards on my Desktop PC to connect to the same wireless router at the same time, specifically as so:   WiFi Adapter 1 using 5Ghz 802.11ac to Router WiFi Adapter 2 using 2.4Ghz 802.11n to Router (same router)   Currently I have them set to 2 different SSIDs, although that certainly can be changed if needed.  To be clear, I want to use both networks to boost speeds, that's the intent here.


Alerting users in danger of being flagged for serial voting

EDIT:  I've been recieving quite a bit of criticism over this question so I have edited it to hopefully reach a compromise that everyone can agree upon.  While I disagree that imposing a downvote limit from one person to another would negatively impact the SE voting system, I understand that imposing such a limit is not an answer that will be agreed upon and thus is not the proper solution.     For this reason I propose an alternate solution that does not impose any limits whatsoever.  Instead of imposing limits, a simple notification system to let a user know when they are in danger of being flagged by the automated system for serial down/upvoting could be put in place.   Adding this alert would effectively discourage people who actually intend to "serial down/upvote."  I'm sure most people who are serial voters are unaware that a system is in place to stop it, and just notifying them that this system exists would be enough to discourage many of them.  To address another point made:  This would also be very helpful to those who run into a user who frequently asks bad questions.  As noted in a previous comment on Monica Cellio's response to this question, the automated system frequently fails when a user spams multiple bad questions and the downvotes are falsely detected as being "serial downvotes." ()  Alerting users that their votes may be reversed by the automated system if they do too many would relieve some of that problem. (Obviously it would not fix the problem, the system is inherently broken when dealing with situations like these, but a true solution to that issue should be left for another proposal).  The original question below is kept only for consistency and so all of the responses make sense.  All future votes on this question should reflect the edit and not the original post.    ORIGINAL QUESTION:  I've asked numerous questions on Stack Overflow.  Just recently I began to notice that almost every new question I ask always gets one downvote, regardless of the quality of the question.  Obviously I don't know who is downvoting my questions, or even if it is the same person each time; but it at least begs the question . . . Could there be someone out there purposely downvoting my questions because of a personal vendetta?  Not that this kind of rivalry happens frequently, but people have it out for each other in the comments section all the time so I wouldn't be surprised if some rivalries form.  I think it would be a good idea to limit how many times one user can downvote another user.  (Obviously the limit would be reasonable, for example you may be only allowed to downvote another user's questions and/or responses 10 times in one month.)  Even if such a limit were imposed and you find that you reach this limit; if the user you wish to downvote truly has bad questions all the time, they will get enough downvotes from other users anyways.  Chances are if a user reaches this limit they are probably trying to abuse the voting system anyways.  If a user frequently reaches this limit it would be a useful indication to look into them for potential serial downvoting.  To any naysayers to this question saying it would be a bad idea because it encourages users to ask bad questions... Think about it realistically.  Would you frequently reach this limit..? I highly doubt it.  And if you would frequently reach this limit, maybe you should stop for a minute and question your voting habits.


Unable to load styles and script from static resource in LWC after summer'19 release

one of my LWC component failed to work after the summer'19 release because it is unable to load styles not the script from the static resource  I have included the custom lwc inside a lightning record page  Here is the error which I am facing


What is the correct verb-form to use in this sentence?

This is the sentence: Out of these two what is the correct grammatical order to express the sentence.  1.) Watching cartoons, movies, dramas develop the human brain  2.) Watching cartoons, movies, dramas develops the human brain  What is it? Develop or Develops?


How many Hamiltonian circuits are there in a complete graph with n vertices?

How many Hamiltonian circuits are there in a complete, undirected and simple graph with $n$ vertices?  The answer written in my book is: $$\frac{\left(n-1\right)!}{2}$$  What is the combinatorial explanation to this?   My best shot was to try to count for each size of Hamiltonian circuit (triangles, quadrilaterals, pentagons and so on), how many of each there is, and to sum them.  So I tried to count for each amount of edges the amount as possibilities, to complete it to the mentioned shapes.   I mean for n vertices, I choose any 2 vertices (that's an edge) and for each other vertex by connecting from each vertex from my edge by new edges, I can create a triangle, which is a Hamiltonian circle of size 3 and so on.  But there are a lot of repeats and that's a mess.  Maybe I didn't get the point at all, because the expression:  $$\frac{\left(n-1\right)!}{2}$$  seems to be to me no more than the amount of Euler circles (each vertex degree is 2) which I order in a circle, so $(n-1)!$ is the possibilities to order $n$ different elements in a circle and divide by 2, because of the reflection.  Isn't a Hamiltonian circuit in such a graph an $n$-cycle, so it could be triangle, quadrilateral, and so on?


What is the advantage for rockets to ?   Wouldn't a single stage with the same amount of fuel weigh less?  Note I would like a quantitative answer, if possible :-)


AUC vs accuracy for model accuracy evaluation

In R I tried to measure the accuracy by performing a classification analysis using logistic regression analysis. I found that there are two ways to measure accuracy. One is AUC measurement using ROC curve and the other is accuracy using confusionMatrix.  When confusionMatrix is used, the probability exceeding 0.5 is regarded as 1, the value less than 0.5 is regarded as 0, and it is judged whether or not it matches the actual value.  If so, what should be considered as the model accuracy? Obviously, the values of AUC and confusionMatrix obtained from one algorithm are different. What is the different?


I am trying to mount a raw image in my ubuntu VM but it returns a mismatch type error:  root@ubuntu:~$ sudo kpartx -a -f -v xenial-server-cloudimg-amd64-disk1.img root@ubuntu:~$ cd /dev/mapper/ root@ubuntu:/dev/mapper$ ls control  ubuntu--vg-root  ubuntu--vg-swap_1 root@ubuntu:/dev/mapper$ losetup NAME       SIZELIMIT OFFSET AUTOCLEAR RO BACK-FILE /dev/loop0         0      0         0  0 /home/usera/xenial-server-cloudimg-amd64-disk1.img root@ubuntu:/dev/mapper$ sudo mkdir /tmp/foo root@ubuntu:/dev/mapper$ mount /dev/loop loop0         loop2         loop4         loop6         loop-control loop1         loop3         loop5         loop7 root@ubuntu:/dev/mapper$ sudo mount /dev/loop0 /tmp/foo/ mount: wrong fs type, bad option, bad superblock on /dev/loop0,        missing codepage or helper program, or other error        In some cases useful info is found in syslog - try        dmesg | tail or so.   I read up online and follow the instruction but the instruction said I should have a loop0s1 under /dev/mapper folder instead. But I don't see anything under /dev/mapper. Is there anything I did wrong?  Thanks  Edit:  root@ubuntu:~$ file xenial-server-cloudimg-amd64-disk1.img xenial-server-cloudimg-amd64-disk1.img: QEMU QCOW Image (v2), 2361393152 bytes  root@ubuntu:~$ sudo fdisk -l xenial-server-cloudimg-amd64-disk1.img Disk xenial-server-cloudimg-amd64-disk1.img: 276.3 MiB, 289734656 bytes, 565888 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes


What is the difference between a C# List and Linked List?

As I understand Linked Lists are useful if I need a list where I need to remove, or add items multiple times after the declaration - things that are not possible/harder to do with an array. But basically I can do the same thing with List Class in C#. So my question is, what is the difference between the two?


Feature request: real time code compilation

Interactive / Real time code compilation for stackoverflow.com. That will improve the answer correctness of the stackoverflow.com.  When adding a new code block, let the user try to compile the code and see the result. It will be useful to demonstrate class designs, algorithms, and logics.


Example of quotient mapping that is not open

I have the following definition:   Let ($X$,$\mathcal{T}$) and ($X'$, $\mathcal{T'}$) be topological spaces. A surjection $q: X \longrightarrow X'$ is a quotient mapping if $$U'\in \mathcal{T'} \Longleftrightarrow q^{-1}\left( U'\right) \in \mathcal{T} \quad \text{i.e. if } \mathcal{T'}=\{ U' \subset X' : q^{-1}\left( U' \right) \in \mathcal{T} \}$$  and the properties:   $q$ is a bijective quotient mapping $\Leftrightarrow$ $q$ is a homeomorphism  In general, $q$ quotient $\not \Rightarrow q$ open.  If $U \in \mathcal{T}, q(U)\subset X'$ is open if $q^{-1}\left( q\left( U \right) \right) \in \mathcal{T}$ but not in general.   I could not find an example of quotient mapping for which $q^{-1}\left( q\left( U \right) \right)$ is not open. I would understand the idea better if you could show me one.


Looking for title of a sci-fi story about a one-way space journey

I'm looking for the title of a Sci-Fi story (probably pre-1990) where a group is sent off into deep space and I believe unbeknownst to them it's a one-way journey.  In the course of the journey they all become very intelligent, they make psychoactive drugs from the plants on board, I recall that they discovered it's a one-way journey to test the affects of space travel, and they redesign/refit their engines and return to Earth.  Lame recall, sorry, that's all I got. Any help appreciated.


Let's say I have strings of symbols that are not in math mode but I'm trying to define kind of a language that is going to be used in a protoboard. So I have to explain how this language works but for long instructions like for example: \verb|chain[x,y](newposition[amp, speed](positioning[long, stop, fullview]())) I don't know how to break it so it stays inside the space defined by \textwidht and starting a new line if necessary.


List all the pairs $(x,y)$ s.t. $x^2 - y^2 = 2020$

List all of the pairs $(x,y) \in \mathbb{Z}^2$ s.t. $𝑥^2 - 𝑦^2 = 2020$. The prime factorization of $2020$ is $2^2 \cdot 5 \cdot 101$. I used the fact that there exists a solution $(x,y) \in \mathbb{Z}^2$ to the Diophantine equation $x^2 - y^2 = n$ if and only if $n$ is odd or $n$ is a multiple of $4$. Since $n$ is a multiple of $4$, there exist a solution. I know there is a solution but I am neither able to obtain the number of solution nor able to get the list all the pairs $(x,y)$.


Can I use only one of my two last names for publishing?

I have 2 last names due to my hispanic background. Soon, I will have to think about my very first publication (field: Medicine/Psychology). Could I use only the first last name for my publishing or will I get into legal trouble with that? My goal is to avoid hassles after marriage, since we are planning to fuse our last names. So, assumed that my maiden name is A. Smith Miller, after marriage I'd be called A. Smith-Johnson, and my publishing name would be A. Smith. Is that possible, or is it mandatory to use the entire last name for publishing?


As a long-time  user (and hater) I was discussing switching to  with a colleague; he suggested using  instead. Since, apparently, it can be used as peer-to-peer without a central server (we are a 3-developer team).   I have not been able to find anything about tools that integrate Git with Visual Studio, though - does such a thing exist?   What are the technologies available for using Git with Visual Studio? And what do I need to know about how they differ before I begin?


I have tried $f(n) = \int_1^n \ln x dx$, but it fails. The difference is  $$\lim_{n\to \infty}(\ln n! - \int_1^n \ln x dx)$$  $\int_1^n \ln x dx = n\ln n -n +1 \\ \ln n! - \int_1^n \ln x dx = \ln n! - n\ln n +n -1 = \ln(\frac{n!e^n}{n^n})-1$  where $\frac{n!e^n}{n^n}\to \infty$, so the limit diverges.  Do we have some function $f(n)$that converges to the series $\ln n!$ ?


Get program RAM usage (in MB) at runtime (Windows 10)

Is there an easy way to find out how much RAM (in MB) does my program use after different operations (large matrix manipulation)? I am using Windows 10.


If a commander becomes a colorless forest, is it still a commander?

In Magic the Gathering, I cast  on an opponent's commander. It is now a colorless forest land. My opponent has an  on the field which gains power if you control your commander. Is the colorless forest land still my opponent's commander? Does my opponent get the Lieutenant bonus?


If I have multiple constructors in a class, how do I avoid duplicate code for those fields which are initialized identically for all constructors, or is this not preferable?  For example:  class ComparableThing<K extends Comparable<K>> {   private int someField;   private Comparator<K> comparator;    public ComparableThing() {     this.someField = 0;     this.comparator = Comparator.naturalOrder();   }    public ComparableThing(Comparator<K> comp) {     this.someField = 0;     this.comparator = comp;   } }   Is there a way to avoid the duplicate code in initializing someField, or is this duplicate code considered acceptable/preferable?


I am venturing into UI/UX design and I would love to dig deeper into this technology, I am a front end engineer html/css/js and I want to learn and be an expert in UI/UX design. If someone could direct me to books and tutorials I have to go through to be a competitive player in this industry.


Need to figure our what a specific symbol is replaced to after macro expansion

Can I view my compiler error in the pre-processed file? I am trying to figure out what a specific symbol is being replaced by after macro expansion. I am using Visual C++. Basically I would like to see the exact error causing line in the pre-processed file.


How to include (print) Latex source code in generated pdf?

I want to include the source code of my latex generated pdf file in the pdf file itself as printed text. Is there any way to do this?


can I trade my hat against line numbers (with offset) in SO code samples?

That would be awesome.  This feature would be a big win for collaboration.


Can anyone help me with exact dep/landing times of specific historical flight?

The flight is LHR to BKK with a stopover in Kuwait l. Flight with Kuwait Airways departing LHR on 29/12/16 at 15.35. Scheduled to arrive in BKK 21.15 30/12/16. The flight was delay d but I need to know exactly when it departed Kuwait and landed in Bangkok please?  KU0411 is flight number  Life saver if anyone could answer


I realy like the editor stackoverflow uses. its nice, plain and simple. Also I realy like the auto image upload to imgur.com Is there any editor out there which can give me the similar functionality specially the image upload feature


Direction of tension force and restoring force

In the above image I have a block of mass m hanging from a mass less pulley with the help of a massless string. The other end of the string is attached to a wall.  $F_g$ is gravitational force acting downward and $F_s$ is the restoring force of spring acting leftward. T represents tension in the string.  I had to find the reading of the spring balance and assumed that it would be the force on the spring balance(to measure extension of spring).  However I can't seem to figure out the tension force between the spring balance and the wall. If I consider that spring balance was a block, then tension force would be leftward and of magnitude T. But what about the tension force leftward? (on the wall)  Similarly in the following image, I again need to find the weight measured by the spring balance:    My intuitive understanding of the problem is since the bodies are not accelarating, the problem is similar to the previous one and therefore the weight measured by the spring is the weight of one block. But is this correct? if so, what would be the direction of restoring force of the spring?  Also if instead, of the spring balance, I imagined a rigid block at the same position, then the net force on the block would be zero, but when I use the spring balance, the measured weight is different, why is this so?  Sorry if I sound very confused.  Edit:  I now know that the tension leftward = T,(in the first diagram) but still don't understand which direction the restoring force of the spring would be (in the second diagram), since force is being applied in both directions


p values and significance in RLM (MASS package) R

I'm running some regression analyses and got pretty confused about R's output when it comes to robust regression models. When I run a OLS -- using the command lm() -- I get this as output:  Coefficients:                 Estimate Std. Error t value Pr(>|t|)   But when I run a robust linear model using the rlm() command, the output looks like so:  Coefficients:                 Value   Std. Error t value   How do I get  the p-values and the significance-levels in an rlm then? Without that, the whole analysis is somewhat pointless. Unfortunately, I couldn't find an answer to that anywhere, so I hope someone around here can help me out. Thanks a lot!!


How to compare the focal length of a 50mm prime lens with the default lens of a point and shoot camera?

To imagine the 50mm focal length of a prime lens 1.4F, can I simply zoom the lens of my point and shoot camera up to 50mm?  Will both the focal lengths be same?  Any other way to imagine the focal length 50mm of prime lens 1.4F when what you only have is a point and shoot camera with 70mm max zoom?


If I put down a draw 4 card and call uno out, can another player place a draw 4 ontop?

My last card was a wild draw 4, I knew my friend had one but I had to put it down. I called uno out and he put his draw 4 ontop of mine. Can he do that?


Why LastModifiedbyid in Trigger.new gives old value

I have noticed the strange behaviour of salesforce due to which even my code broke down in production.  I was trying to stop the user from updating some field..I used before udpate trigger and code like Trigger.new[i].LastModifiedbyId..  Ideally it should give the current user in Trigger.new[i].LastModifiedbyId in  but it gives oldrecordLastModifiedbyId..  Although userinfo.getuserid resolves the problem later.  Any idea about this behaviour of salesforce.


Proper fstab entry to mount a samba share on boot?

I am a little confused on the proper fstab entry for a samba share in Ubuntu 12.04     I can get the drive to mount manually by using:  sudo mount -t cifs //192.168.2.2/raid_drive /mnt/homeserver -o username=jon,password=password  So I tried putting this in fstab:  //192.168.2.2/raid_drive /mnt/homeserver cifs username=jon,password=password,iocharset=utf8,mode=0777,dir_mode=0777 0 0  Which gives me this error in syslog:  kernel: [ 2217.925354] CIFS: Unknown mount option mode kernel: [ 2217.936345] CIFS VFS: default security mechanism requested.  The default security mechanism will be upgraded from ntlm to ntlmv2 in kernel release 3.3  This  says to use smbfs although I believe smbfs is deprecated?   What is a common fstab configuration for a samba share in Ubuntu 12.04?   EDIT:  Using the accepted answer below I was initially getting this error message (from dmesg):  [   45.520883] CIFS VFS: Error connecting to socket. Aborting operation [   45.520990] CIFS VFS: cifs_mount failed w/return code = -115   although it turns out this was due to network connectivity issues, and not related to improper fstab entry.


How do I bulkify queries for directly or indirectly related records?

This is a canonical question and answer developed by the community to help address common questions. If you've been directed here, or your question has been closed as a duplicate, please look through the resources here and use them to shape more specific questions. To browse all canonical questions and answers, navigate to the  tag. This question and answer is owned by the community! If you can improve it and make it more useful, you're welcome to edit it. I have a collection of records, like a List<sObject> or the Trigger.new context variable. I need to query other records that are related to these records either directly or indirectly, and I want to use the related data to make further updates. When I write a query in a loop, like for (Account a : Trigger.new) {     Account parent = [SELECT Name FROM Account WHERE Id = :a.ParentId];     // ... }  I keep hitting Salesforce query limits, and I know this is not best practice. What can I do to avoid this problem and bulkify my code?


How may one calculate  $$\lim_{n\to\infty} \ \left(\left(\sum_{k=1}^{n} \frac{1}{3k-1}\right) - \frac{\ln n}{3}\right) \ ?$$


Is it possible to create "real" 3D effects within a Beamer presentation using Stereoscopy (for 3D monitors)?  What I mean by that is:   Duplicate the slides left and right (for both eyes) Animations so that certain parts of the slide pop out of the screen, i.e. different translation in the left and right view Support for stereoscopic images, or even videos (with the multimedia or movie package). An example for a stereoscopic image:      Is there a package that allows creating these kinds of effects? Or a workaround with the normal Beamer package? Thanks.


Show that $\frac{2}{\pi}x<\sin x<x$ for $0<x<\frac{\pi}{2}$

By considering the function $$f(x)=\sin x - x$$ for $0<x<\frac{\pi}{2}$, show that $$\frac{2}{\pi}x<\sin x<x$$ for $0<x<\frac{\pi}{2}$  My first step was to differentiate $f(x)$, upon which I get $\cos x - 1$. However, I do not know how to procede from there.


How to get total length of objects in array correctly

Is it even possible to get length of all objects inside an array? Let say i have an array which looks like that:    var foo = [{     "id": 1,     "path": {         "1": [{             x: 21,             y: 22         }, {             x: 22,             y: 12         }],         "2": [{             x: 21,             y: 22         }, {             x: 22,             y: 12         }]     } }];  for (let x in foo) {     var path = foo[x].path;     for (let c in path) {         console.log(path[c]);     } }     How can i correctly get total lenght of objects inside path array here?


What is the average postdoctoral salary in China?

I got one postdoctoral offer just after completion of my PhD study. I am not sure about the amount of fellowship. I do not have any experience in postdoctoral work. What is the average salary given to postdoc fellow in Wireless Communication Engineering  particularly in China?


How should I teach my son to play video games?

My son will be 4 soon, and he already enjoys playing a few educational games on my tablet or his mother's phone (he plays maybe as much as an hour a week).  I'm a gamer, and we've tried playing a few "real" games together, such as Mario Kart.    He doesn't grok controls very well.  We can show him specific combinations of controls, but he has trouble putting them all together, and invariably winds up getting stuck.  Once he gets stuck, it stops being fun for him, and he decides to do something else.  The answer may simply be "wait until he's old enough to figure it out on his own", but I'm not sure.  Should I be trying to teach him how to work the controls on video games?


Apache nolonger able to start (could not bind to address error)

I run a local apahe2 and PHP set up on my Ubuntu desktop to test stuff. Mainly so I can avoid uploading utter garbage when I am creating new code.  However after a particularly problematic upgrade it seems Apache is no longer running. When I try to start or restart it I get this:    * Restarting web server apache2 AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message (13)Permission denied: AH00072: make_sock: could not bind to address [::]:80 (13)Permission denied: AH00072: make_sock: could not bind to address 0.0.0.0:80 no listening sockets available, shutting down AH00015: Unable to open logs Action 'start' failed. The Apache error log may have more information.                                                                          [fail]  * The apache2 instance did not start within 20 seconds. Please read the log files to discover problems    I couldn't rember where the error logs might be found (it has beena  long while) but I googled it:   However /var/log/apache2/error.log is empty  How can I figure out what is wrong and fix it?  Notes: I am aware of the whole cannot determine FQDN thing and as I am running it only for me I've never been that bothered so long as it actually worked and I could test what I had written.


How to compare two columns and find differences in Excel?

I have two columns in Excel that I want to compare and find the differences between them.  Suppose:   Col A has 50 numbers, i.e. 0511234567 Col B has 100 numbers in the same format


Is there an example of checking on if a WCF Service is online?

I will have a client application using a proxy to a WCF Service.  This client will be a windows form application doing basicHttpBinding to N number of endpoints at an address.  The problem I want to resolve is that when any windows form application going across the internet to get my web server that must have my web server online will need to know that this particular WCF Service is online.  I need an example of how this client on a background thread will be able to do a polling of just "WCF Service.., Are You There?"  This way our client application can notify clients before they invest a lot of time in building up work client-side to only be frustrated with the WCF Service being offline.  Again I am looking for a simple way to check for WCF Service "Are You There?"


I received a dataset containing some "XY" coordinates that are supposed to correspond to some locations in natural reserves/national parks in Costa Rica. I'm trying to use the proj4 package in R to try to convert these coordinates to lat/long (using the project(..., inverse = TRUE) command), but I cannot figure out which projection was used to get the XY coordinates, so I cannot invert the projection to get the lat/long. How can I guess which projection/coordinate system was used? A few points:   X,       Y 193087, 1056379 193587, 1056917 211524, 1032512 213201, 1032612


Disable the activation of the menu bar when Alt is pressed in Windows 7

In Windows 7 how can I disable the function that activates the menu bar when Alt is pressed?  Are there some registry values to modify this behaviour?


Program does what is inside every if-statement in the method. Not supposed to

I have a program which I am writing which in one particular case enters every if-statement. But it isn't supposed to. I govern whether or not it should do just that by a boolean value which i send with the reference to the method. But it still won't work properly.  Here is the code snippet of the two methods included:      void tilStasjon(String startStasjon){          boolean sjekkStasjon=true;         while(sjekkStasjon){             System.out.println("Vennligst tast inn til-stasjonen: ");             String sluttStasjon=input.next().toLowerCase();             if(stasjonerMap.containsKey(sluttStasjon)){                 if(sluttStasjon!="ringen"){                     sjekkStasjon=false;                     beregnRuter(startStasjon, sluttStasjon);                 }             }else{                   System.out.println("Stasjon ikke funnet.");                 sjekkStasjon=true;             }         }     }      void beregnRuter(String startStasjon, String sluttStasjon){          Stasjon til=stasjonerMap.get(startStasjon);         Stasjon fra=stasjonerMap.get(sluttStasjon);         ArrayList<Linje> fraLinjeListe=new ArrayList<Linje>(fra.linjeList);         ArrayList<Linje> tilLinjeListe=new ArrayList<Linje>(til.linjeList);         int tilStasjonsNummer, fraStasjonsNummer;         int retning;         double tid= 0.0;         String endeStasjonsNavn;         boolean overgang=false;          tilStasjonsNummer=0;         fraStasjonsNummer=0;          for (int i = 0; i < fraLinjeListe.size(); i++) {             for (int j = 0; j < tilLinjeListe.size(); j++) {                 if(fra.linjeList.get(i).equals(til.linjeList.get(j))){                     System.out.println(fra.linjeList.get(i).linjeNummer);                     Linje aktuellLinje=linjerMap.get(fra.linjeList.get(i).linjeNummer);                     tilStasjonsNummer=aktuellLinje.stasjonsNummer(til);                     fraStasjonsNummer=aktuellLinje.stasjonsNummer(fra);                     retning=tilStasjonsNummer-fraStasjonsNummer;                     tid=beregnTid(retning, overgang, aktuellLinje);                      endeStasjonsNavn=aktuellLinje.endestasjon(retning);                     System.out.println("Ta T-bane linje " + aktuellLinje.linjeNummer + " fra " + startStasjon + " til " + sluttStasjon + " i retning " + endeStasjonsNavn + ". Estimert reisetid: " + tid);                              }                }         }     }   Below here is the method where the problem occurs. It enters both the outer if and else-if. Why is that?      double beregnTid(int retning, boolean overgang, Linje aktuellLinje){         double tidMellomStasjoner;         double tid=0.0;         int absRetning=Math.abs(retning);         double tidOvergang;          if(overgang=false){             if(aktuellLinje.type==0){                 System.out.println(absRetning);                 tidMellomStasjoner=1.8;                 tid=tidMellomStasjoner*absRetning;             }else if(aktuellLinje.type==1){                 tidMellomStasjoner=1.4;                 tid=tidMellomStasjoner*absRetning;             }         }else if(overgang=true){             if(aktuellLinje.type==0){                 System.out.println("Test");                 tidOvergang=7.5;                 tidMellomStasjoner=1.8;                 tid=(tidMellomStasjoner*absRetning)+tidOvergang;             }else if(aktuellLinje.type==1){                 tidOvergang=5.0;                 tidMellomStasjoner=1.4;                 tid=(tidMellomStasjoner*absRetning)+tidOvergang;             }         }         return tid;      } }


Let X be a space and C a connected subset of X. Suppose C $\subset$ D $\subset$ Cbar . Then D is connected.

We know that C is a connected subset of X, iff C is connected in the subspace topology. Therefore, from the definition of subspace topology, we know that there should be a V subset of C, and there should exist an open set U that belong to the topology, s.t. $V = $U $\cap$ C$.   Also, $C \subset D \subset$ $C^{bar}$, from here we can say that one of them in dense in D, I think it will be C bar. Then, i need to show that there doesn't exist a separation of D, i.e. there doesnt exist non empty sets U and V in D. I am having a hard time figuring how to relate those and show D is connected or not separated.   Can someone help me here?


Force new users to go through animated tutorial before they post for the first time

Do not allow people to post the minute they created an account.  Let them ask the question but not allow them to post.  Let them stew for 30 minutes and force them through a nice animated tutorial on what they should do before they post and enforcing the fact that bad questions will not get an answer.  If they had a Need to know! basic rules introduction forced on them asking them at the end to check a box I understand! some might ask better questions and help the community instead of flooding the site with bad questions.  The presentation should be on a timer without the ability to skip and highlight the similar questions asked before that might give them the answer.  Also for the first next 9 posts they should have to check a box next to the first 5 of each similar questions before posting.  I do not mean to be harsh, but the truth is I see more negative votes on questions then positive. It's like 90% of the time people give -1 to first questions.


BIND: How to refer requests to other DNS servers in different predefined networks

Let's say I have two independent networks net1.local and net2.local each of which is connected to a bigger network local through a router.  Each of 3 networks have their own independent DNS server. Now, a host in net1.local tries to resolve a name from net2.local. Something like this:  nslookup host1.net2.local   The DNS server located in net1.local does not know anything about net2.local hosts, and the DNS server located in the bigger network only knows the top domain names as it contains these records:  net1       IN A      192.168.10.1 net2       IN A      192.168.20.1   What would be the best practice to configure DNS servers to achieve this??


my system arch is amd64, i installed i386 as foreign arch and ran sudo apt dist-upgrade but after it finished, i keep getting this error while using apt:      apt-get: relocation error: /usr/lib/x86_64-linux-gnu/libapt-private.so.0.0: symbol ZN3URIcvNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEB5cxx11Ev version APTPKG_5.0 not defined in file libapt-pkg.so.5.0 with link time reference   even when i use aptitude:     aptitude: relocation error: aptitude: symbol ZN3URIcvNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEB5cxx11Ev version APTPKG_5.0 not defined in file libapt-pkg.so.5.0 with link time reference   any solution?


Creating menu item and adding more than 1 plugin in QGIS?

Because if I execute these lines for each plugin, I created a menu item for each plugin.  I created many plugins and wish to place them in a new menu item (not traditionals)


Writing conditional (if/then) statements into ArcGIS Field Calculator using Python Parser?

I have gotten stuck on seemingly simple ArcGIS field calculator python expression.  I obtained a great answer to a another similar question a few years ago: . Now I need to populate a new field based on 6 ranges of values (bedrock depth).  My attempt at writing this expression is below:    I just need to populate the empty field "bedrockdp" using the ranges in the toc called brockdepmin.     Pre-Logic Script Code:  def !GRIDCODE! (value):     if value >0 and value < 50:         return "0 - 50 cm from the surface"     else:         return "n/a"   bedrockdep =  GRIDCODE (!bedrockdep!)


Can you save a certain character from dying in Minecraft Story Mode Episode 4?

Is there any way to save Reuben in Episode 4?


Pouring concrete slab around wood posts of covered porch

I have a covered back porch.  Sloped roof attached to the house on one end and supported by four 4x4's which are cemented in the ground on the other end (I assume there are cement footers below the soil.  This was done by the previous owner). I want to remove the existing pavers and pour a concrete slab as my floor.  Are there any dangers to having it poured around the wooden posts holding up the porch roof?  Do I need to protect them somehow before the pour?


Adjective for "with the same name" / "same-way called"

I’m looking for an adjective that is similar to eponymous as in:     He is playing a role of Terminator in the eponymous movie.   Except that it should be possible to use this adjective as a substitute for the phrase “same-way called” as in:     The Luxembourg village called Shengen and the _______  located in Eurasia.


iMac has two internal drives, what is the best setup?

My iMac (Retina 5K, 27-inch, 2014) has a permanent internal 120GB drive on the main board and I just added a 2TB SSD internal drive as well. I'm essentially starting over with a clean system. I'm wondering what is the best setup for these two drives? By best I guess I mean 'safest'. I just went through having a dead fusion fusion drive and losing data so I'd like to be careful and smart about how I set this up. Any help would be greatly appreciated.


I want to be able to set up a Git repository with various folders that will later be populated with files.  The idea being that one developer creates the source control layout, while other developers populate the repository with usable files.


How to create a file which is named like a command line argument?

I was wondering how to make a file named as a flag, e.g., if I wanted to make a folder named -a, what commands would do the trick?   I tried mkdir '-a', mkdir \-a, and neither worked. I'm on Ubuntu.


Probability of two integers' square sum divisible by $10$

Given two random integers $a$, $b$ calculate probability of $a^2$ + $b^2$ is divisible by $10$.  I've tried to simulate this process and got a result about $0.18$ (maybe incorrect), but have no idea why.


Programmatically access the  section of a web.config?

Is there any way to access the <compilation /> tag in a web.config file?  I want to check if the "debug" attribute is set to "true" in the file, but I can't seem to figure out how to do it. I've tried using the WebConfigurationManager, but that doesn't seem to allow me to get to the <compilation /> section.  Update:  I know I could easily just load the file like an XML Document and use XPath, but I was hoping there was already something in the framework that would do this for me. It seems like there would be something since there are already ways to get App Settings and Connection Strings.  I've also tried using the WebConfigurationManager.GetSection() method in a few ways:    WebConfigurationManager.GetSection("compilation")// Name of the tag in the file WebConfigurationManager.GetSection("CompilationSection") // Name of the class that I'd expect would be returned by this method WebConfigurationManager.GetSection("system.web") // Parent tag of the 'compilation' tag   All of the above methods return null. I'm assuming there is a way to get to this configuration section since there is a class that already exists ('CompilationSection'), I just can't figure out how to get it.


(This is probably a basic question, and may be a duplicate; if so, just let me know.)  Suppose there are two clients A and B, and some server C. Suppose B and C establish an HTTPS tunnel, and C sends a response to B. And suppose B records the response, and sends it to A.   Can A verify that the alleged response from C was actually sent by C?   This is essentially equivalent to "Are HTTPS responses non-repudiable?". As far as I am aware, HTTPS only provides a secure channel, but does not provide digitally signed traffic.  Motivation  I'm tentatively planning to create a social network add-on which would allow users to flag other users who have sent them offensive material via private messages. I would hypothetically run a web service which would receive flag requests, and in order to avoid spam flags, I would need some way for the flagger to voluntarily send me a minimum but sufficient amount of information to verify that the private message actually exists.   In this scheme, I am A, the flagger is B, and the social network is C.   Is there any sane way to do this, without compromising the flagger's security?


How does dual wielding work in Diablo 2?

I'm looking for general information on how dual weilding works in Diablo 2:  Which classes can do it? What weapons/weapon types can they do it with? How does it affect combat exactly? Does it double your attack speed or damage? Are they on their own separate attack timers or is it a chance to swing both at the sametime thing? Do I have to click faster to make it work?  Am I better off putting a weapon with elemental damage in one hand than the other? What about two weapons of different speeds?


I'd like to use Excel 2010 to show on the x-axis when discrete events occurred and on the y-axis the magnitude of those individual spurious events. My goal is to try to visually analyse when different magnitude events occur and to see if there is a periodicity to these events.  How to go about this using Excel graphs?


Could we be permitted to provide a reason for rolling back?

I just had an occasion where someone reformatted the code in my question, not because it was ill-formatted, but to match his preferred style. I would have liked to be able to type a reason for rolling back the edits when I did so - could the ability to do that be added?


I haven't found out a good contour to evaluate the following integral.  $\displaystyle\int_{0}^{\infty}\dfrac{x\cos ax}{\sinh x}dx$. Well, a natural way should consider the complex integral  $\displaystyle\int_{\Gamma}\dfrac{ze^{iaz}}{\sinh z}dz$.   However, I don't know how to find a suitable contour $\Gamma$ to surround the zeros of $\sinh z$ which are $z=\pi ni $ for $n \in \mathbb{Z}$.  I'd really appreciate any help.  Best regards.


Prove that $\lambda = 0$ is an eigenvalue if and only if A is singular.

I'm trying to prove that statement: Prove that $\lambda = 0$ is an eigenvalue if and only if $A$ is singular.  I'm not sure if my proof is totally correct:  Suppose that $\lambda = 0$ if det(A) = $\lambda_1 \cdot \lambda_2 . . .\lambda_n = 0$ then A is singular.  If anyone could show me a better proof that would help.


How to align a set of very long equations

I'm trying to set up my equations for 3 hours and it's driving me crazy. I'm new in LaTeX so I don't master it at all.  This is the closest, with the simplest code, that I could get.  \documentclass[a4paper,11pt]{report}  \usepackage{amsmath} \begin{document}  \begin{align} dX(t)=&-f1*X(t)L(t)dt+g1*U(t)dt\\     &-\sqrt{f1*X(t)L(t)}dW1(t)+\sqrt{g1*U(t)}dW2(t) \end{align} \begin{align} dL(t)=&-f1*X(t)L(t)dt+g1*U(t)dt-f2*U(t)L(t)dt+g2*Y(t)dt\\     &-\sqrt{f1*X(t)L(t)}dW1(t)+\sqrt{g1*U(t)}dW2(t)\\     &-\sqrt{f2*U(t)L(t)}dW3(t)+\sqrt{g2*Y(t)}dW4(t) \end{align} \begin{align} dU(t)=&f1*X(t)L(t)dt-g1*U(t)dt-f2*U(t)L(t)dt+g2*Y(t)dt\\     &+\sqrt{f1*X(t)L(t)}dW1(t)-\sqrt{g1*U(t)}dW2(t)\\     &-\sqrt{f2*U(t)L(t)}dW3(t)+\sqrt{g2*Y(t)}dW4(t) \end{align} \begin{align} dY(t)=&f2*U(t)L(t)dt-g2*Y(t)dt\\     &+\sqrt{f2*U(t)L(t)}dW3(t)-\sqrt{g2*Y(t)}dW4(t) \end{align} \end{document}   And it's giving me this   It's close to what I want but I want the dX, dL, ... to be aligned aswell. And, if possible, but not very important, to get only one number of ref. for the whole set.  I tried numerous ways with align, split, aligned and I couldn't do it.  I've the conviction that the answer is very simple but I don't know what to try anymore, I've read so many post about it here and I'm still blocked.  Thank you.  Edit :  As suspected, it wasn't tricky at all, thank you very much.


What to do when you find a bad link in an answer?

If a link has gone stale in an answer, what is the correct way to report this in the SO universe?  e.g. Jon's first link in    I have added a comment but not found the correct link yet.


Overlap between a Schengen type C visa and a long-stay (type D) visa

Recently I have been issued a tourism Schengen visa to France valid until end of October. Also I applied for a student visa to Italy for a master's program that starts in September. It seems there will be overlapping weeks between the two visas yet they are of different types (one is type C the other is type D).  Would that cause a problem and force me to cancel one visa or the other?


Finding a vector potential for a solenoidal vector field

I have to find a vector potential for $F = -y \hat{i} + x \hat{j}$   This is what I have done:  We know that, if $\nabla \cdot F = 0$, we can construct the following:  $$F= \nabla\times G$$   Where $G$ is the vector potential we want to find out.  We know what F is, so it is just about doing the following:  $$\frac{\partial G_3}{\partial y} - \frac{\partial G_2}{\partial z} = -y$$  $$\frac{\partial G_1}{\partial z} - \frac{\partial G_3}{\partial x} = x$$  Noting that the partial derivatives with respect to $z$ are zero in this case, we get:  $$G = \frac{-x^2-y^2}{2}+C$$  Where $C$ is just the gradient of any scalar.  I am given a whole list of possible vector potentials:    Now I could use the most brute method: Trial and error with each possible vector potential given, using the equation:  $$G_n = \frac{-x^2-y^2}{2}+C$$  Solving for $C$ and seeing whether it holds.  This is pretty tedious; is there any brightest method?  Thanks.  EDIT  $$\frac{\partial G_2}{\partial z} = y$$  $$\frac{\partial G_1}{\partial z} = x$$  $$\frac{\partial G_2}{\partial x} - \frac{\partial G_1}{\partial y} = 0$$  I get:  $$G = <xz,yz,0>$$  Which indeed satisfies:  $$F= \nabla\times G$$   But this option is not in the list...  Now let's set $G_2 = 0$:  $$\frac{\partial G_3}{\partial y} = -y$$  $$\frac{\partial G_1}{\partial z} - \frac{\partial G_3}{\partial x} = x$$  $$\frac{\partial G_1}{\partial y} = 0$$  I get:  $$G = <0,0,\frac{-x^2 - y^2}{2}>$$  Which indeed satisfies:  $$F= \nabla\times G$$


Where is the best place to discuss downvotes?

I see some users indicating that they've received downvotes in the comments, and asking their downvoter to justify why they downvoted the question.  Is this acceptable for discussion? Should this occur in the comments, or somewhere else?


I can't update any apps in Google play store

Why I can't update any apps and it keeps on saying that I have insufficient storage but I think its not the problem because I have storage. So what should I do?


Varying transparency of symbols within single layer in ArcMap

I have a polygon layer which I am drawing in ArcMap using a graduated color symbology:  Is it possible to vary the transparency between the classes, so that the transparency tapers off with the color ramp? For example, draw the first range (0.175 - 0.225) with no transparency, but the last range (0.45 - 0.52) with 50% transparency. This is the effect I am trying to mimic, taken from Google Earth as a polygon KML:  One workaround could be to create a separate layer for each class using a definition query, vary each layer's transparency, then group them together but I am looking for a less cumbersome approach.


I'm an amateur and I'm buying a Nikon D5200. What exactly are filters used for? Do I need one for basic nature photography?


Android setText problem error with editText

I'm trying to set a textview to a editText text. When I do that I have this error:      Process: com.example.game, PID: 9829     java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference         at com.example.game.MainActivity.onClick(MainActivity.java:79)         at android.view.View.performClick(View.java:5637)         at android.view.View$PerformClick.run(View.java:22429)         at android.os.Handler.handleCallback(Handler.java:751)         at android.os.Handler.dispatchMessage(Handler.java:95)         at android.os.Looper.loop(Looper.java:154)         at android.app.ActivityThread.main(ActivityThread.java:6119)         at java.lang.reflect.Method.invoke(Native Method)         at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)   It's strange because when I do system.out.println with the text I get   I/System.out: Player1   Can someone help me ? My code:          System.out.println(p1.getText().toString());         System.out.println(p1.getEditableText().toString());         j1.setText(p1.getEditableText().toString());         j2.setText(p2.getEditableText().toString());   p1 and p2 are editText and j1 and j2 are TextView. I don't know if it's the problem but they are in different resource layout.


i query this SQL query:  SELECT * FROM [DB].[dbo].[Table] WHERE [DATE] BETWEEN '01-01-2016' AND '31-03-2016' AND ([TIME] >= '00:00:00' OR [DATE] > '01-01-2016') AND ([TIME] <= '00:00:00' OR [DATE] < '31-03-2016');   But in SQL Studio the result to another date and time.    [DATE] = VARCHAR(10) (DD-MM-YYYY) [TIME] = VARCHAR(10) (HH:MM:SS) 24h   How to fix ?


How to prove that $\lim\limits_{x\to\infty} f(x)/x=L$

Let $f\colon(0,\infty)\to\mathbb R$ be differentiable on $(0,\infty)$ and suppose that $\lim\limits_{x\to\infty} f'(x)=L$.         a. Show that for any $h>0$, $\lim\limits_{x\to\infty} \frac{f(x+h)-f(x)}h=L$.      b. Show that $\lim\limits_{x\to\infty} \frac{f(x)} {x} =L$.   this is a differentiation question.  i don't know how to solve this question  Because it is Korean, it is difficult to deal with this cite. So for me, it is not easy to write.  thank you


I have to install Ubuntu 17.04 on my computer. On the computer in question, I have a data partition. During the installation of Ubuntu 17.04, does the option to "Erase disk and install Ubuntu" also delete the empty partition, or leave it as an empty disk partition?   Original question (Italian)  Avrei una domanda. Io devo installare ubuntu 17.04 sul mio computer. Io sul computer in questione, ho una partizione di dati. Il mio quesito è: se durante l'installazione di ubuntu 17.04 selezione l'opzione cancella disco e installa ubuntu, cancella anche la partizione dei dati che è vuota oppure la lascia come partizione del disco vuota? Grazie per la collaorazione.


How to connect MySQL server without putting user/pass in the main page

I have a main page on my site and I am trying to make a connection to the MySQL server and get some data from the database. But the problem is that when I want to establish a connection I have to put the username and password in the page which doesn't seem wise to me. I added a part of my code related to this problem. <!DOCTYPE html> <html lang="en"> <head> </head> <body> <?php $host = "localhost"; $userName = "username"; $password = "12345678"; $dbName = "MyDB";  $connection = new mysqli($host , $userName , $password , $dbName); if ($connection->connect_error) {     die("Connection failed due to this error : " . $connection->connect_error . '<br>'); } else{     echo "Connected successfully"; { </body> </html>


Let $R$ be a PID, $a\in R$ be a nonzero nonunit in $R$. Prove that $R/Ra$ is an injective module over itself.   If $R$ is a PID, every $R$- divisible module is injective, but the question concerns with $R/Ra$-module, so I have no idea to solve this problem. Help me.


I am using a rig made by someone as a prop in my scene, but it has these borders / seams on the texture. I think it may be because the model is divided a lot, or it could be something else. Picture:   I googled this, but I didn't find anything about this problem. Can someone tell me how to fix this or show me a tutorial? Also, I am a beginner so excuse me if this is a dumb question.  Project file to recreate problem:


How I do to modify the contents of a ISO file?

I want to open a ISO file, add files and then burn it to a disc.  By example, I get the . That ISO have 2.6mb, and if I burn the iso, I will lost the remainder 697mb of the disk!   To burn the ISO, I use CD Burner XP or ImgBurn, but I don't know which free tool I can use to add/remove files before burn.  Thank you very much!


What are the requirements for the Greed portal to appear?

I've killed hundreds of goblins, on multiple difficulties, in rifts, out of rifts... Bu no greed portal has opened yet.  I'm currently doing mainly rifts (I have a huge pile of rift fragments), so can these portals open in rifts? And do they require torment or above? Is there a level requirement before they can appear?


How can I change my SQL statements to be prepared (and secure) statements?

Basically I want to protect myself from SQL injections. I have tried searching online and watching videos but cannot understand exactly what I have to change because as far as I can tell, everyone does it a little bit differently. Any help is appreciated!  ?php // Create connection $con = mysqli_connect("IPAddress","User","Password","DBName"); // Check connection if ($con->connect_error) {     die("Connection failed: " . $con->connect_error); }  $sql = "INSERT INTO Email_Subs (email) VALUES ('$_POST[email]')";  if ($con->query($sql) === TRUE) {     echo "You have successfully subscribed!"; } else {     echo "Error: " . $sql . "<br>" . $con->error; }  $con->close(); ?>


The Additional Drivers settings interface is no longer available in Ubuntu 17.10  How can I install proprietary drivers in Ubuntu 17.10?  I need drivers for Wifi & Bluetooth (BCM43142) and Intel Graphics.  The earlier Additional Drivers program showed a package named jockey but it no longer seem to exist in repositories.


Encrypt USB That Is Compatible With Windows

I want to encrypt a USB stick, and be able to decrypt it on Windows as well as Ubuntu. How do I do this & what programs do I need to use?


Change font size in context by percentage

Font sizes can be set with (more or less) absolute commands such as \large, \Large, \LARGE, and so on.  Are there also commands that can increase or reduce a font size by some proportion or percentage not in absolute terms but relative to the preceding text?  I am hoping to find a way to do this in the midst of chapter titles, which are set in the preamble to be \LARGE\bfseries. But when a colon appears in a chapter title, followed by a subtitle, I am being asked to reduce the size of the subtitle by just a small amount — and the result of using the absolute \Large is not satisfactory. I could redefine \Large just for this situation, but I'd prefer to find a relative command to change font size, as described above, as that would be useful in many other situations.


What is the most efficient way to create an N-times-a-character string in JavaScript?

I have a char ('-') and a number (80) of times it should be repeated in a string. I need to get a string of that char repeated given number of times:  -------------------------------------------------------------------------------------------------------------   I know I can do result += myChar x N times in a loop. I don't think it is very efficient. Is there a better way to do that?  By the most efficient I mean: fastest


What is wrong with this calculation of work done by an agent bringing a unit mass from infinity into a gravitational field?

Let us assume that a gravitational field is created by a mass $M$. An agent is bringing a unit mass from $\infty$ to distance $r < \infty$, both measured from mass $M$.  The agent is always forcing the unit mass with a continuously changing force $\vec F(\vec x)$, $\vec{x}$ being the distance pointing radially out from $M$.   According to classical mechanics, it holds that $\vec F(\vec x) = \frac{GM}{x^2}\hat{x}$, with $G$ being the gravitational constant.  The work is calculated as follows: $$W = \int_\infty^r\vec F(\vec x)\cdot d\vec x$$ $$=\int_\infty^r{{F(x)}\,dx\cdot cos(\pi)}$$ $$=-\int_\infty^r{{\frac{GM}{x^2}}dx}$$ $$=-GM[-\frac{1}{x}]_\infty^r$$ $$=GM[\frac{1}{x}]_\infty^r$$ $$=GM[\frac{1}{r}-\frac{1}{\infty}]$$ $$=\frac{GM}{r}$$  The body moved against the force's direction (the angle between them was always $\pi$). So the work should have been negative. But since $r$ is the scalar distance from $M$, it is positive like $G$ or $M$, yielding the result always positive.  What is wrong here?


Why not "messager"? Or "messenge"?  E.g. Why don't we say:     Send me a messenge on instant messager.


How can I convert from a SID to an account name in C#

I have a C# application that scans a directory and gathers some information.  I would like to display the account name for each file.  I can do this on the local system by getting the SID for the FileInfo object, and then doing:  string GetNameFromSID( SecurityIdentifier sid ) {     NTAccount ntAccount = (NTAccount)sid.Translate( typeof( NTAccount ) );     return ntAccount.ToString(); }   However, this does not work for files on a network, presumably because the Translate() function only works with local user accounts.  I thought maybe I could do an LDAP lookup on the SID, so I tried the following:  string GetNameFromSID( SecurityIdentifier sid ) {     string str = "LDAP://<SID=" + sid.Value + ">";     DirectoryEntry dirEntry = new DirectoryEntry( str );     return dirEntry.Name; }   This seems like it will work, in that the access to "dirEntry.Name" hangs for a few seconds, as if it is going off and querying the network, but then it throws a System.Runtime.InteropServices.COMException  Does anyone know how I can get the account name of an arbitrary file or SID?  I don't know much about networking or LDAP or anything.  There's a class called DirectorySearcher that maybe I'm supposed to use, but it wants a domain name, and I don't know how to get that either - all I have is the path to the directory I'm scanning.  Thanks in advance.


Here is my basic setup:  ArrayList<String> myList = new ArrayList<>(); myList.add("test"); String[] arr = myList.toArray(new String[myList.size()]); System.out.println(arr);   And i get the classic error: [Ljava.lang.String;@1540e19d  Can anyone explain and help me fix it?


In definition of vector multiplication, the direction of the resulting vector is given by the right hand rule. However I don't know any mathematical requirement to pick right hand instead of left for this purpose. Is there any?


Is Bernoulli's equation the correct explanation of a curved soccer ball?

I saw a lot of materials supposing that the Bernoulli's equation explains the curvature of a soccer ball: since the ball is spinning, two sides of the ball would experience different velocities, and due to Bernoulli's theory, the side with slower velocity generates a higher pressure and push the ball to the other side.   However, when we first learnt the Bernoulli's equation, one of the fundamental criteria is that it must be applied on the same streamline. And in the above case, the streamlines on the two sides of the ball are separated. So how does the Bernoulli's theory explain the curving-ball phenomenon? Is that a misconception?


What causes a tension force? I can't understand why there is a tension force acting Also, let's take a simple example of tension force," a block tied to a end of the rope which is hanging". When will be the tension force larger or smaller than the weight of the block ? And why? Please answer.


How to add spaces at every X digit in a binary or hexadecimal number?

I would like to format binary or hexadecimal numbers with a space separator at each 2 or 4 digit (or any other value like 8 digit or more).  A small picture is better than a long explanation, here is what I would like to do:    As you can see in this mwe, I use the fmtcount package with padzeroes:      \documentclass{article}     \usepackage[utf8]{inputenc}         \usepackage[T1]{fontenc}               \usepackage{fmtcount}     \begin{document}             Binary value : {\padzeroes[16]\binarynum{129}}$_{(2)}$ %             should display 0000 0000 1000 0001$_{(2)}$              Hexadecimal value: {\padzeroes[8]\Hexadecimalnum{65000}}$_{(16)}$ %             should display  00 00 FD E8$_{(2)}$     \end{document}   What I want to do is displaying numbers with various radix (2, 3, 7, 8, 10, 16) given a decimal number and format these numbers correctly with spaces and leading 0 (without having to perform the conversion by myself).  I already found some posts with similar questions, but none of them achieve this (they display number with thousand separators, like the numprint package, every 3 digits; or they do not make it automatic). Here are these posts :         EDIT two other linked questions:       I also prefer to use pdflatex.


Linux - couldn't mount RDWR because of unsupported optional features (400)

I try to run Android from SD-card. This card is prepared. There are partitions: boot(FAT32), rootfs(ext4), system(ext4), cache(ext4) and usedata(ext4). Boot partitions has files to run u-boot: MLO, u-boot.bin and uImage. To run it I use commands  mmcinit 0 fatload mmc 0 0x80000000 uImage setenv bootargs 'console=ttyO2,115200n8 mem=456M@0x80000000 mem=512M@0xA0000000 init=/init vram=10M omapfb.vram=0:4M androidboot.console=ttyO2 root=/dev/mmcblk1p2 rw rootwait rootfstype=ext4' bootm 0x80000000   Than I see how Linux starts. But after few seconds on step of loading rootfs I see an error message  [    4.015655] EXT4-fs (mmcblk1p2): couldn't mount RDWR because of unsupported optional features (400) [    4.036499] sd 0:0:0:0: [sda] Attached SCSI removable disk [    4.079986] List of all partitions: [    4.083801] b300        31162368 mmcblk0  driver: mmcblk [    4.089660]   b301             128 mmcblk0p1 f9f21f00-a8d4-5f0e-9746-594869aec34e [    4.097839]   b302             256 mmcblk0p2 f9f21f01-a8d4-5f0e-9746-594869aec34e [    4.106018]   b303             128 mmcblk0p3 f9f21f02-a8d4-5f0e-9746-594869aec34e [    4.114288]   b304           16384 mmcblk0p4 f9f21f03-a8d4-5f0e-9746-594869aec34e [    4.122436]   b305              16 mmcblk0p5 f9f21f04-a8d4-5f0e-9746-594869aec34e [    4.130676]   b306            8192 mmcblk0p6 f9f21f05-a8d4-5f0e-9746-594869aec34e [    4.138916]   b307            8192 mmcblk0p7 f9f21f06-a8d4-5f0e-9746-594869aec34e [    4.147094]   103:00000     524288 mmcblk0p8 f9f21f07-a8d4-5f0e-9746-594869aec34e [    4.155334]   103:00001     262144 mmcblk0p9 f9f21f08-a8d4-5f0e-9746-594869aec34e [    4.163574]   103:00002   30342128 mmcblk0p10 f9f21f09-a8d4-5f0e-9746-594869aec34e [    4.171874] b310            2048 mmcblk0boot1  (driver?) [    4.177734] b308            2048 mmcblk0boot0  (driver?) [    4.183593] b318        15179776 mmcblk1  driver: mmcblk [    4.189453]   b319          102400 mmcblk1p1 00000000-0000-0000-0000-000000000000 [    4.197692]   b31a           10240 mmcblk1p2 00000000-0000-0000-0000-000000000000 [    4.205932]   b31b               1 mmcblk1p3 00000000-0000-0000-0000-000000000000 [    4.214141]   b31d          262144 mmcblk1p5 00000000-0000-0000-0000-000000000000 [    4.222351]   b31e        13228032 mmcblk1p6 00000000-0000-0000-0000-000000000000 [    4.230682]   b31f         1572864 mmcblk1p7 00000000-0000-0000-0000-000000000000 [    4.238891] No filesystem could mount root, tried:  ext4 [    4.244812] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(179,26) [    4.254089] CPU1: stopping   I don't know why it happens.  How can I solve this problem?


What is the use of super(ClassName,self)._init_()

I have a class that looks like this:  #!/usr/bin/env python class Foo:     def __init__(self, x):         self.x = x     def bar(self):         self.bar1_out = self.x + 5         self.bar2_out = self.x + 1         return (self.bar1_out,self.bar2_out)     def qux(self,myvalue = None):         first, second = myvalue or self.bar()         return first + 3, second + 6  def main():     """docstring for main"""     f = Foo(5)      mbr_out1, mbr_out2 = f.bar()     print mbr_out1, "\t", mbr_out2      mqx_out1, mqx_out2 = f.qux()     print mqx_out1, "\t", mqx_out2      qout1, qout2 = f.qux((1))     print qout1, "\t", qout2  if __name__ == '__main__':     main()   I saw some implementation that suggest using super      def __init__(self, x):         super(Foo,self).__init__()         self.x = x     def bar(self)         #etc.   My questions are:   What's the use of super(Foo,self).__init__() How does it differ from self.x=x How can I make my code top above produce the same result by using super()


When exporting a .obj or .fbx how do you keep the color/texture?

I've been looking up tutorials and sites for days now to help me figure this question out, but nothing has been working for me. I am fairly new to Blender, so this is a new experience for me! I know that UV Mapping may have something to do with it, not quite sure.   Here is a simple tree I made on the right. I followed this tutorial:     However, every time I try to export it and import it into ROBLOX Studio, I get the picture on the left:  What would the best solution be? I also would like to know how to do it if I did add textures and not just plain colors (unless they follow the same procedure).   Sorry for the nooby question, thanks again:)


Compiler doesn't see template specialization?

I have template in my .h file:  template <typename T> void addToolsAreaItem(){     T* item = new T(_image, this);     doSpecifiedStaff<T>(item);     _tools.addTool(item); }   and its specialization in .cpp file:  template <> void ImageWorkspace::addToolsAreaItem<Preview>(){     _preview = std::make_unique<QGraphicsView>(_splitter);     _imagesLayout.addWidget(_preview.get()); }   Class Prewiew is empty and is used only for specialize behavior of one case (when preview button is toggled).   But I get compiler error:  imageworkspace.h:45: error: new initializer expression list treated as compound expression [-fpermissive]      T* item = new T(_image, this);                ^~~~~~~~~~~~~~~~~~~  imageworkspace.h:45: error: no matching function for call to ‘Preview::Preview(ImageWorkspace*)’      T* item = new T(_image, this);                ^~~~~~~~~~~~~~~~~~~   Does compiler see specialization? How to fix it?   Function is called as addToolsAreaItem<Preview>() from sorces.


Boot Camp External Drive only booting to one computer

Firstly, I apologize for duplicate posts -- I realized that I wasn't signed in to my account on StackExchange.  I followed these instructions (Is it possible to use Boot Camp with Windows 10 from an external HDD?) to install Windows 10 to my external SSD (Samsung T3). I followed Alex Lambert's guide (the one with most upvotes & correct answer), and was able to install and boot Windows 10 successfully.  I ran to a problem today, as I was connecting the drive to two other Macs until I noticed that my drive was not being seen from the boot menu (option key), although I could see both of my drives (my drives are partitioned in half: 250GB for Windows (NTFS) and 250GB for Data for both OSes, Windows and OS X (exFAT)) in OS X on the other computer.  The computer I used to install was a MacBook Air Mid 2013 and the computers I used to test were two MacBook Pro Retinas made between 2014 and 2015.  Please help, apologies for the noob question (I'm new to this site).  Thanks.


sum of series $\frac{n}{1\cdot 2 \cdot 3}+\frac{n-1}{2\cdot 3\cdot 4}+\frac{n-2}{3\cdot 4 \cdot 5}+\cdots \cdots n$ terms

sum of series $\displaystyle \frac{n}{1\cdot 2 \cdot 3}+\frac{n-1}{2\cdot 3\cdot 4}+\frac{n-2}{3\cdot 4 \cdot 5}+\cdots \cdots n$ terms  assuming $\displaystyle S_{n} =\frac{n}{1\cdot 2 \cdot 3}+\frac{n-1}{2\cdot 3\cdot 4}+\frac{n-2}{3\cdot 4 \cdot 5}+\cdots +\frac{n-(n-1)}{n\cdot n+1 \cdot n+2}$  $\displaystyle S_{n} = \sum^{n-1}_{r=0}\frac{n-r}{(r+1)\cdot (r+2) \cdot (r+3)}$  wan, t be able to solve after that , could some help me with this


Computing second partial derivative with polar coordinates

Consider the polar coordinates with $x=r\cos\theta$ and $y=r\sin\theta$.  I can show using the chain rule that $$\frac{\partial}{\partial x} = \frac{x}{r} \frac{\partial}{\partial r} -\frac{y}{r^2} \frac{\partial}{\partial \theta}$$   What is the method to compute $\dfrac{\partial^2}{\partial x^2}$? I don't know how to do it.


Is there an option in Windows 7 (or 3rd party) to offer Tethering (that is, act as a WiFi hotspot while being connected to a WiFi network?)


Passing integer array to method that uses a generic array of elements?

I have the following class   public class TestAlgorithm<E extends Comparable<? super E>>  {     public void testing(E[] array)     {         for(int i = 0; i<= array.length; i++)         {             ... // processing code (not important here)         }     } }   in my main application class class I have this...  public static void main(String[] args) {     int [] test = {3,7,8,5,2,1,9,5,4};     TestAlgorithm<Integer> myAlgo = new TestAlgorithm<Integer>();      myAlgo.testing(test); }   Which to me - looks like it makes sense - but I get the following error when I try to run it...     The method testing(Integer[]) in the type TestAlgorithm is not applicable for the arguments (int[]) app.java /TestApp/src/Application line 10 Java Problem


All the guidance that a self moderated community should need:     Be respectful.   With the instructions to the elected moderators on enforcement, use your best judgment.  This is respectful to the community and those trusted in enforcing the code.  The elected moderators are just that, they are elected by those that they will be moderating. They should know their communities better than anyone else.   If they are trusted to be fair and equitable by the community and make sure the communities are perceived in the best light possible they should be respected and trusted by the company.  This is reasonable, it scales, this allows for handling anything, this allows for mistakes and corrections.  My experience has been,     If someone needs more than two words to know how to behave, a thousand more is   not going to make a difference.   Why can we not just have this as our Code of Conduct?


Calculate the area under $f(x) = \sqrt x$ on $[0,4]$ by computing the lower Riemann sum for $f$ with the given partition

Where $x_i = \dfrac{4i^2}{n^2}$ and letting $n \rightarrow \infty$  I don't know how and where to begin.


Let's say - $F(x) > G(x)$ for all $x$ in $E$.  So is it true that ?  $$\int F(x)\,dx  > \int G(x)\,dx$$ or I can use this statement only when the two functions are non-negative functions.  Thanks!


Sometime before episode 12, we learn Harime Nui lost her left eye from Matoi Isshin slashing her with a half-scissor.  Around episode 20, Harime Nui is pierced through the chest by Ryuuko, also by a half-scissor, but that time, she did not experience pain and healed from this more serious wound instantly.  It is also revealed that Harime Nui was fused with Life Fibers from birth having been developed inside a Life Fiber cocoon.  Given these facts, why did   Harime Nui experience pain when slashed by Isshin? Her eye not heal from the wound?


Short connection at IAD (Dulles international airport)

I am flying from New Orleans to Dulles (IAD) on United Express, and from IAD to Frankfurt on United. I have a short connection (45 minutes) in IAD.   I'm trying to figure out how can I make it:  Will I need to go throughout security and border check since I'm leaving the US? How big is IAD airport? and are there different terminals for domestic and international flights? If so, how long would it take to walk between them?


Using string literal regex variables to create another regex pattern

I would like to get a date from a text and convert it in seconds. The pattern of the date is Day Month Year Hour . I'm using regex to match the pattern but The regex is long and not readable. So I created a variable for each regex. Now I would like to how can I create another matching pattern using those variables. I'm using javascript and here is my code  ```javascript  / detect the day let day = /(lundi|mardi|mercredi|jeudi|vendredi|samedi|dimanche)/i;  // detect the num of the day let numDay = /(0[1-9]|1[0-9]|2[0-9]|3[0-1])/; //detect the month let month = /(janvier|fevrier|mars|avril|mai|juin|juillet|aout|septembre|octobre|novembre|decembre)/i; // detecter the year let year = /(197[0-9]|20[0-9][0-9])/; // detecter the hours in min and sec let hour = /([0-1][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]/;  let validFormat = `${day} ${numDay} ${month} ${year} ${hour}`;  let expression = "Mardi 12 Novembre 2013 12:02:21";  let found = expression.match(validFormat);  console.log(found);   ```


Let $$A= 1! \cdot 2! \cdot 3! \cdots 1002!$$  $$B= 1004!\cdot 1005! \cdots 2006!$$  Prove that $2AB$ is square. Help guys, I tried, I really did but I couldn't.


The magnetic moment of a particle (and a neutrino)

Is the magnetic moment of a particle an intrinsic property or is there a formula to find it? What is its source?  Is there a formula or a general explanation that can account for the $\mu$ of known particles: electrons, protons, neutrons and neutrinos?  I searched the web and found different values for the neutrino, ranging from 10^-10 to 10^-19, how is such great discrepancy possible? Can we use the formula given for neutrinos (see ) for any other particle?  Can you briefly explain the genesis/rationale of that formula: $$3eG_Fm_\nu /8\pi^2 \sqrt{2}$$ and how it applies to other particles?They say in that article that its  value is proportional to the mass of the neutrino, why so? In what way  ismass  related to it?