I recently came across a problem related to class creation/modeling.  Model animal kingdom as classes. Use your classes to create various objects represented as a virtual zoo. Add 20 animals to this virtual zoo (in your main method of your program and make let each animal make a sound. This should not be 20 different species).  I thought about the problem and decided to go with an abstract class Animal rather than an interface. Then i added two classes Bird, Mammal as inherited them by Animal.   My implementation    public abstract class Animal{        abstract Sound MakeSound();     }      public class Bird : Animal     {        private Sound _sound;        public Bird(Sound sound){        _sound = sound;     }     public Sound MakeSound(){           return _sound;        }     } //same as above with Mammals  public class Program {   Animal crow = new Bird("Crow sound");   Console.WriteLine(crow.MakeSound());   Animal dog = new Mammal("Dog sound");   Console.WriteLine(dog.MakeSound());  // and so on with other animals }   My questions are -    What is wrong with my implementation?  What would be the correct way to design the animal kingdom as per oops concepts? In what scenario do we use an interface over abstract class and vice versa. (with real world example)   Kindly suggest some bang on online material where i can improve on such problems. Thanks.

This may be a generic OOP question. I wanted to do a generic comparison between an interface and an abstract class on the basis of their usage.   When would one want to use an interface and when would one want to use an abstract class?


What are some of the names of chemical compounds (minerals our what not) which make the healthy (sandless) pink salt pink?

I have heard it is from an ancient ocean floor's deposits that have since been uplifted by the Himalayan orogeny, but what in that ocean water made the salt pink. I've been to the Bonneville Salt Flats and the salt there is a normal white color.  Other questions, for example  just concern the taste in dishes. I am concerned with the actual difference in chemical composition.


Some people act in ways that provoke surprised or shocked reactions from others, mainly because they enjoy getting those reactions and not because of any inherent desire to perform the action itself. For example, I suspect that this is a primary motivating factor behind the recent  phenomenon -- the My Little Pony show itself would probably not attract hords of adult male fans, were it not for  the incredulous reactions which the fandom elicits. Is there a word to describe this sort of behavior?  ("Provocative" seems off -- it refers to the fact that a reaction is elicited, but not that this is the motivation behind the behavior.)

What's the word to describe someone who acts arrogantly and always disagrees with others unreasonably in order to upset people around him/her?  [I'm not looking for adjectives like unpleasant, annoying, unfriendly, rude, I'm looking for a more specific term like opinionated, didactic, loquacious, gregarious ]  I think I'd come across it before but I've forgotten what it is..


I'm using Drupal 7, and I had a vocabulary "Destinations". Under this vocabulary, I had terms with 2 levels. For example:   ASEAN -- Brunei -- Indonesia -- Laos EUROPE -- Spain -- Greence -- Portugal     For all 1st level taxonomy terms of this vocabulary (ASEAN, EUROPE), I want to display them as a view, with child taxonomy. Eg:   ASEAN -- Brunei  (term name & description) -- Indonesia  (term name & description) -- Laos (term name & description)   EUROPE -- Spain  (term name & description) -- Greence  (term name & description) -- Portugal (term name & description)     For all 2nd level taxonomy terms, I want to display nodes which have the term. Eg:    Brunei -- Package 1 -- Package 2   Spain -- Package 3 -- Package 4     Is there any way I can configure the views to display result as above? It might have something to do with contextual filter, but I don't know how to configure the parameters.   Any idea on how to achieve this?

Case: I have a taxonomy vocabulary namely 'categories'. It consists of some parent terms with their child terms as shown.   Parent1   -p1child-1   -p1child-2   Parent2    -p2child-1    -p2child-2   I want to create a view which work only for a particular set.  Suppose in this case I will create 2 views, each for both parent terms and both will have different set of exposed filters and sort criteria.  So if I visited taxonomy/term/parent1 or taxonomy/term/p1child-1 or  taxonomy/term/p2child-2, it would render that specific view of parent1.  is it possible ?  Please help


Can a 'curse' or 'polymorph' transform any creature into a humanoid?    In Volo's Guide to Monsters, a note suggests a 'curse' can turn someone into another humanoid - the 2nd row of the Monstrous Origin table (p. 118) says:     You are the victim of a Curse or Polymorph spell.   Mr. Geddarm's book suggests that one could become a  playable (N)PC via either of these two source-spells. Note: Volothamp is portrayed as an unreliable source (guest writer 'Elminster Aumar' expands on this) / arguably not RAW.  Let us briefly explore each spell type below:    Bestow Curse (abridged):     At the GM’s option, you may choose an alternative curse effect, but it should be no more powerful than those described above. The GM has final say on such a curse’s effect.   This suggests Bestow Curse can do virtually anything, so long as it impacts the recipient less than the listed curse set. This leeway is explicitly subject to table rulings / under DM discretion.    Polymorph (abridged):     The new form can be any beast whose challenge rating is equal to or less than the target’s.   This should simply NOT work. Though one can argue that the  obviously applies to most beasts and most humanoids, 5e D&D is unique in that humanoids are NOT viable / selectable end-forms with this 4th level spell (no other edition had this limitation-severity). Note: this DOES work with the more powerful  True Polymorph spell - especially if concentration is held for an hour. At 9th lvl, is not an abuse of RAW, RAI or RAF.  Let us assume that the author(s) of Volo's Guide meant True Polymorph / kept it simple &/or elegant.    Can the Bestow Curse spell alter one's form?  Three possible interpretations:   Rule of Cool: Why not? This racial modification is far less grievous, arduous &/or impactful than any of the other listed Cursed possibilities in the PhB (q.v. Basic Rules, pg. 218). Cursed race-change = 'modify your character's abilities &/or innate magical powers appropriately'.  Against R.A.I.: A 3rd level spell ('Bestow Curse') CANNOT out-perform a 4th level spell ('Polymorph'). So deeply abusable! A variant human paladin gains long-range Darkvision, more strength - and easily  an entire orc tribe! Not a 'curse' at all, is it? Bestowing this 'curse' on a rabbit and making a pop-up elven ally is also right out of the question ('This curséd rabbit is our archer... and also does our cooking and cleaning! Poor thing.'). Some R.A.W. blending: Possibly give slight change in mass and appearance - and nothing else. Thus, the aforementioned vuman paladin would look a bit like an orc but be the same size-weight (NPC orc: 'Hm. You thin. Comrade orc, eat this sand-witch!'), yet not gain any magical or racial abilities. Logically this must NOT not work on rabbits... or Purple Worms... or anything that did not start as a living-breathing humanoid in the first place.   The main problem with this third ruling: some racial abilities are amazing curses (arguably the point of said spell &/or Volo's RAW option). Example: Drow sunlight-blindness IS a curse - with bonus universal hatred for any UnderElf that isn't . Second example: a PC that looks, smells, sounds and walks as a zombie (no other disadvantages) is a fantastic curse - both story-wise and 5e D&D thematically (especially if the PC goes to town unaware / cannot see his or her appearance).  Basic question / sum up: If 'Bestow Curse' spell transforms any creature into a humanoid of the caster's choosing (on failed save) - how does any self respecting DM keep power-balance &/or player abuse-ability in RAW-check?

In Volo's Guide it is suggested that a curse could transform someone into a race of 'monstrous origin' (p. 118). Does this apply to the Bestow Curse spell specifically? Note: this is a  (my apologies).  In film / lore, such magic does , ,   - or even  transformative curses.  Points & Concerns:   this is within guidelines for a 'reasonable' curse, i.e. less harm than the listed set Bestow Curse writeup encourages DM-homebrewing &/or interpretation. Great role-play possibility / RAI (hence most myths, fairy tales, cartoons, legends, etc) this could be subject to abuse, temptation to bestow a 'curse' as a blessing / boon one could also change: age, size, weight &/or gender (all great curse ideas... but RAW-legal?)   Summation:  What are the limits of the 3rd lvl / Necromatic Bestow Curse spell for transformation?


In a previous question, I asked about my exposure problems and there I found out that my lens cannot adjust the aperture/aperture blades. Every time I try to adjust the aperture to a higher number my and take a picture, an error comes up. I tried to check the lens and I saw that the aperture didn't change, thus giving me an error. Sometimes, the aperture blades also gets stuck and doesn't go back to its original position. I've tried cleaning the contacts of the lens and camera but the camera and the lens still loses contact. I also tried borrowing another lens, adjusted the aperture and the camera still loses contact with the lens. It seems my camera loses contact with the lenses every time I change the the aperture, though it works fine if I use the smallest available aperture.  What is the possible cause of the lose of contact?  Camera: Nikon D90  Lens: AF-S DX NIKKOR 18-55mm f/3.5-5.6G VR II  Thanks in advance!

I know there are quite a few posts out there about the famous "Press Shutter Release Button Again" error. But mine seems to be quite weird. I own a Nikon D3200 with the standard 18-55 mm lens. It works great and takes amazing pictures but only if my aperture is fully open (f/3.5). Once I close it to, for example, f/4 it shows me the "Press Shutter Release Button Again" error. The weird part though is that it will take a picture, but the picture will either be way too dark or way too bright depending on the lighting.   I checked and the mirror is moving without any issue and the aperture "arm" is also moving freely. I think it might be the lens? I am not sure about this though since I am quite new to DSLR cameras.   I doubt that this is normal, don't know if anybody has some advice?


I'm sure that someone has brought this up before, but I can't find it. On some stack exchange sites, particularly smaller ones, not all questions get answered straight away. This means that a question which hasn't gotten answered will get less and less attention, making no-one answer it. Is there any way for these questions to be 'recovered' so that people can see them?  If someone is looking for a question to answer, they will look for the most recent questions on the site, or most recent on a tag, if it is a large site like stack overflow. This means people generally don't look at old questions, as they are probably already answered. How can these questions be resurfaced?  Also, people typically don't want to waste their time on answering that already has an answer, even if the answer is not accepted. This means that questions which have been answered, but with a bad answer, don't get the attention they need.  In short, how can we create an environment such that question answerers can see questions that should be seen?

I asked a question almost as soon as I got my account. I got a few decent answers, but none of them helped solve my problem. The question has long since become buried by newer questions, and there's still no accepted answer. Unfortunately, because there are quite a few answers with votes, to a casual observer it probably looks like the question was answered and I just neglected to mark an answer as accepted, and the system does not consider it "unanswered".  Or, I asked a question that was a bit more difficult to answer. After waiting for some time, I received no answers, little or no comments, and only a few views. The question does show up in the "unanswered" list, but no one has answered my question.  In either case, what's the protocol for me to try to get this question answered?  I see several options:   Post the question a second time, possibly linking to the original, to get attention for the original question. This is encouraged on sites like Reddit.  However, it's probably not appropriate here, since we're encouraged to check for duplicates and not submit a question that's already been asked by someone else, so this probably falls under that heading. Wait for some kind of wiki-like talk page to be implemented, then post a plea on the talk page for input and hope that activity on the talk page bumps up the question. Edit the question, but do nothing further on the Stack Exchange site. If I edit my post to say that I haven't accepted any of the current answers but am looking for more, then the question might get answered eventually by people browsing through old questions to find something they can answer. Post the question on other sites, but link to my original question on Stack Exchange. People will either answer here, or they'll answer on the other site and I can post the accepted answer here myself.  This might be considered spamming, so it might be better to do this without the link.      For more information, see the "" page in the .


I have read somewhere that Leibniz championed the idea that the world is continuous as this was needed for his (or maybe Newtons) new invention (or discovery?) of calculus. But if I am not mistaken a fundamental principle of the quantum world is that things can only take on disjointed, discrete values. So does calculus break down when studying the subatomic world? if so, does particle physics simply rely on algebra and arithmetic or is there some form of higher level math that was need to be conceived to work in this new domain?

I was confused when I was listening to a Quantum Mechanics lecture online. Are space and time assumed to be continuous or discrete in Quantum Mechanics?  I can see the question is vague, but this is so since I am confused.


My mobile phone has been stolen and I have blocked my number and bought a new sim with same mobile number. When I reset password and followed the instructions, it shows at the end of page: Google could  not verify your account.  Please help me.

I have forgotten the password or username for my Google account, or I'm unable to access my account for other reasons.  How can I recover my account?  (This Q&A is meant as a general description for all Google and Gmail username/password questions. See: )


I'm trying to find an optimal solution for sending large amount of small messages (usually around 1000 per sec, can be up to 10000 per sec. Each message is up to 1KB large), over the internet, but with minimal possible latency (think e.g. about financial data). I started with basic Duplex WCF channel - that was great for local network. Than I needed to change my contract to be oneway (OperationContractAttribute with IsOneWay property set to true), as otherwise each message waited for confirmation and so network latency was counted twice for each message. Even after this my service still sometimes doesn't catch up (and on the server side I'm just reading messages from the queue and immediately sending, on the client side I just enqueue message after receiving and do not block).  I'm wondering if there is some overhead caused by sending large number of small messages. Is there a better way (e.g. some sort of streaming over TCP)?  Edit1: Based on feedback I'm adding little technical info:  Our service is in Singleton instance mode that can be called concurrently ([ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Multiple)]).  We didn't configure throttling so it has default values (however there is just very few concurrent clients - 1 to 4)  In fact we use duplex channel - client calls in (registers) and then server is sending large amount of messages to client. Client itself performs very little calls. Server calls the client via callback Channel in synchronized way (we iterate through blocking queue), however very, very frequently (those mentioned ~1000 messages per sec, but even few thousands per sec).  Edit2: Explaining why this is not a duplicate to  question:  In our scenario we actually have very small number of clients (let's even consider just one single client), but large number of messages being continuously sent to that one client - so it's something like streaming scenario.  We already did the measurements of typical client scenario and service throughput and found that we currently cannot scale well in some situations (for over-the-internet client at the short times in day when there is larger number of messages needed to be sent - then those are probably queued by WCF as we temporarily see increasing delay in receiving time).  Scaling out to multiple server boxes isn't unfortunately viable solution for us (one client need to be connect to one server for whole day).

Does anyone have any experience with how well web services build with Microsoft's WCF will scale to a large number of users?  The level I'm thinking of is in the region of 1000+ client users connecting to a collection of WCF services providing the business logic for our application, and these talking to a database - similar to a traditional 3-tier architecture.   Are there any particular gotchas that have slowed down performance, or any design lessons learnt that have enabled this level of scalability?


$$f(x)=x^3+64$$  Again, I am really not sure how to do this I tried to factor but it clearly was not the right answer

$$125x^3 + 216$$  I have tried to factor it but because the square root of $216$ is a decimal, I can't figure out how to do the problem.


For example, assume my attack and defense log is full and I am still in my current season (about mid-way). Some of my attacks/defenses are still able to be shared with my clan while others cannot be shared. This excludes attacks/defenses that can be replayed by me but cannot be shared with the clan.  What would cause an attack or a defense to no longer be able to be shared? All I know that only the first four attacks and defenses can be shared and that a new season causes every attack and defense (from last season) to be no longer shareable nor viewable.  This is not a duplicate as I am asking of all the requirements that must be met to become unshareable only.

When I open up my defense messages and attack messages, replays are not available, even my most recent attacks. Any help?


First, why the vector bundle, structured from principal bundle, has structure group $G$ ? Second, how to prove the principal $G$-bundle, structured from vector bundle, is principal bundle according the Definition 2.3.3 ? Picture below is from the 65 of Jost's Riemannian Geometry and Geometric Analysis. In fact ,I think the definition 2.3.3 is not a good definition.

Why fiber of $(P\times V)/G\rightarrow P/G$ isomorphic to $V$ ? I think the fiber should be $V/G$, but it is not isomorphic to $V$ Picture below is from the 66 page of   Jost's Riemannian Geometry and Geometric Analysis


I use both \begin{verbatim} ... \end{verbatim} and \verb.something. in my document. I would like the contents of \begin{verbatim} ... \end{verbatim} to be displayed in a smaller font. I found , which is kind of what I want. In that answer, the verbatim font can be customized via this command:  \makeatletter \newcommand{\verbatimfont}[1]{\renewcommand{\verbatim@font}{\ttfamily#1}} \makeatother   But I would prefer this to be applied to every verbatim environment automatically.   Then I tried to transfer  answer to my problem, but this also makes the contents of \verb.someting. small, which is not what I want.    I also tried defining a custom verbatim environment like this:  \newenvironment{smallverbatim}{ \verbatimfont{\footnotesize}\noindent\ignorespaces\begin{verbatim}}% {\par\noindent% \ignorespacesafterend\end{verbatim}}   But this gave me:  ! LaTeX Error: \begin{smallverbatim} on input line 526 ended by \end{itemize}.   Is there a way to do what I want to do?  What I need is some kind of macro that replaces every \begin{verbatim} with \verbatimfont{\footnotesize}\begin{verbatim}, so it shouldn't be impossible, but I have no idea how to do it.

How can I modify the following command to make it work?  \newcommand{\code}[1]{\begingroup \fontsize{10pt}{10pt}\selectfont \begin{verbatim} #1 \end{verbatim} \endgroup}   I currently get the following error on the close of the following verbatim block:  ! Undefined control sequence. <argument> ...endgroup ^^M^^M$\eta_{xi} = r_{xi} -                                                    q_i \cdot p_x$ \\^^M$q_i ... l.227     \end{verbatim}


I bought a choke made of litz wire. The wire is enameled all the way to the ends. How does one go about stripping this wire?

I want to repair my computer mouse cable which has become disconnected from the PCB. The wire is insulated with enamel and I have to remove it before soldering it back onto the board.  How should I remove the enamel?


In Aura components, we use  to display pre-formatted HTML. As per the document, there is no corresponding LWC component. Is there any way I can display HTML content stored in a metadata field as-is?

I am currently having an issue to show the content fetched from salesforce database to UI. The data is stored in HTML form and I want it to show on UI using LWC without escaping HTML. Previously we were having specific component in lightning and VF page to unescape HTML and show the HTML content on UI. I am looking something similar to it.  Here is the code,  <template if:true={teamRecords} >     <template for:each={teamRecords} for:item="team" for:index="index">

{team.item.siteComponent.Title__c}

                     {team.item.siteComponent.Description__c}

     </template> </template>


I want to hit enemy's axe to break it. How this is properly played in D&D 5e? And what about shield or armor? Can I attack these items to break it?

My players have been asking to improvise specific combat actions, mostly the archer wanting to aim at specific body parts. I haven't been able to find anything in the DMG or the PHB on the subject so I was wondering how I should deal with this.    How (if at all) should an attack roll be modified when targeting a specific body part? If there is not RAW on this I am open to playtested house rules per .


When using Android ICS, can I use my phone without having my calendar and associated items going on Google Calendar but just synchronizing with Outlook (the desktop app) ? If yes, how may I do this ?

I have Galaxy Europa GT-I5500 Android phone with me.  The problem I am facing is I am able to Sync my Contacts and Notes with my Outlook 2007, but I am not able to sync my my phone calendar with Outlook 2007.   I'd appreciate if anyone can help me with the problem I am facing.


From Wikipedia we can :     In statistics, dependence or association is any statistical   relationship, whether causal or not, between two random variables or   two sets of data. Correlation is any of a broad class of statistical   relationships involving dependence, though in common usage it most   often refers to the extent to which two variables have a linear   relationship with each other. Familiar examples of dependent phenomena   include the correlation between the physical statures of parents and   their offspring, and the correlation between the demand for a product   and its price.   They introduce some concepts: dependence (or association), causality, correlation and statistical relationship.  Ok, (linear) correlation does not imply causation and that's fine, but I do not clearly understand the differences between aforementioned concepts, introduced in that wikipedia article.  I read a lot of post on this community but I did not find a complete answer to this question.

Suppose we have a set of events $\Omega$, containing events $A$ and $B$. My econometrics professor tried to distinguish the following three terms today.    Causation --- $A$ causes $B$ if the occurrence of $A$ always leads to another specific outcome $B$. For example, clapping my hands causes a sound to be emitted.  Prediction --- $A$ predicts $B$ if on average, $B$ is the expected outcome from $A$ occurring. In other words, whereas causality is deterministic, prediction is probabilistic. For example, studying for a test would predict doing well on the exam. But there's no guarantee.   Correlation --- $A$ and $B$ are correlated if when one occurs the other does too. But there may be some hidden variable causing both.    Are these distinctions meaningful? Or did he make these terms up?   My Questions   What is the difference between causation and correlation?  Are "causes" always deterministic?


I'm very new c# and xml  I'm trying to convert a txt file to XML, then with a button apply an XSLT to the XML with C# (and display it in the program)  I have managed to convert the txt file to XML (although it only takes 1 lot of data), but cannot figure out how to apply the XSLT to the XML.   Is there some way to insert the stylesheet link into the XML () or is this what "XSLcompiledTransform" is meant to do ?   Below is the c# that I have been testing -      private void button1_Click(object sender, EventArgs e)     {         string filePath = "authors.xml";          dataSet1.ReadXml(filePath);          dataGridView1.DataSource = dataSet1;         dataGridView1.DataMember = "authors";     }      private void dataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e)     {      }      private void button2_Click(object sender, EventArgs e)     {         String[] data = File.ReadAllLines("TextFile.txt");          XElement authors =             new XElement("authors",              new XElement("title", data[0]),              new XElement("Released", data[1]),              new XElement("Price", data[2]));            authors.Save("authors.Xml");     }      private void button3_Click(object sender, EventArgs e)     {         try         {              // Generating a temporary HTML file             string outfile = Path.GetTempFileName().Replace(".tmp", ".html");              // Creating the XslCompiledTransform object             XslCompiledTransform transform = new XslCompiledTransform();              // Loading the stylesheet file from the textbox             transform.Load("authors.xslt");              // Transforming the XML file and storing output in HTML file             transform.Transform("authors.xml", outfile);         }         catch (Exception ex)         {             MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);         }     }      private void button4_Click(object sender, EventArgs e)     {         // Create a reader that contains the style sheet.         XmlReader reader = XmlReader.Create("authors.xslt");         reader.ReadToDescendant("xsl:stylesheet");          // Load the style sheet.         XslCompiledTransform xslt = new XslCompiledTransform();         xslt.Load(reader);      }      private void button5_Click(object sender, EventArgs e)     {         string filePath = "authors.xml";          string[] lines = File.ReadAllLines(filePath);          textBox1.Text = System.IO.File.ReadAllText(filePath);     } } }

I want to apply an XSLT Stylesheet to an XML Document using C# and write the output to a File.


Short story read in the 60's or 70's, an astronaut has to enter an alien ship and collect the tears/sweat? of an alien to use as a wonder drug for humans. The alien has some sort of presence which affects the mental state of any human near it.

I remember once many years ago reading a short story about how the Human Race established contact with an alien race. One of the exchanges involved one alien and one human meeting in orbit on a space station for the purpose of collecting what the alien would extrude from it's pores. This "elixir" would extend life expectancy in a human who ingested it. The problem arose that the alien was so "foreign" and grotesque that if one was to "view" it, one would go mad. This story is a narrative of the man sent to the station for the collection and his encounter with the alien.


How can I align equations in nested align ?  \documentclass{article} \usepackage{amsmath,amssymb,amsfonts} \usepackage{flexisym}  \begin{document}  \begin{equation*}     CT_i = \left\{\begin {aligned}         &CT_{i1} = \tau \\         &CT_{i2} = H(M).e(g, g)^{s\alpha} \\         &CT_{i3} = h^s \\         &CT_{i4} = H(M)^{t.H_1(ID_{Ui})} \\         &CT_{i5} = H(M)^{t.H_1(ID_{ESP_i})} \\         &\left.\begin{aligned}             &CT_{i6} = g^{q_y(0)} \\             &CT_{i7} = H(attr(y))^{q_y(0)}         \end{aligned}\right\}\forall j \in   \mathbb{A}_{Ui}     \end{aligned}\right. \end{equation*}  \end{document}   In this case, last two lines are not aligned with rest of the lines (alignment at C, = g/h).  Please help. Thanks in advance.

I want to write a three line equation with left curly brace for all three, right curly brace for bottom two ones and some text at right bottom of right curly brace. All with proper alignment. I wrote following code.  \documentclass{article} \usepackage{amsmath,amssymb,amsfonts} \usepackage{flexisym}  \begin{document}  \begin{equation*}     \begin{aligned}         K_{\mathbb{A}_{Ui}} =\begin{cases}             D                =\ g^{ \frac{ (\alpha + r) }{\beta} }\\             \left.\begin {aligned}                 &D_j           &=\ &g^r . H(j)^{r_j} \\                 &D_j\textprime &=\ &g^{r_j}             \end{aligned}\right\} \forall j \in   \mathbb{A}_{Ui}         \end{cases}         \end{aligned}     \end{equation*}  \end{document}   It is giving some problems.   Second and Third lines are aligned but they are not aligned with the first one. I want alignment to occur at start of "D", "=" and "g" for all three. Right now, the text at right of right curly brace is coming at center. I want it to shift down and come at bottom.   Please help. Thanks in advance.


There are a number of questions on this site about the protection spell that Lily gave to Harry through her death, but one question doesn't seem to have been touched on:  Why aren't such spells commonplace?   and its answers make it clear that the intention to sacrifice yourself is a vital part of the spell, but even so, would that really be so uncommon?  The books make it sound like Harry's protection is incredibly rare, even unique.  But Rowling herself, quoted in that question, says...     Now any mother, any normal mother would have done what Lily did.   And not just mothers! Many fathers and grandparents would likely do the same, even friends or lovers.  Wars and armed conflicts inevitably lead to stories of comrades "throwing themselves on the grenade" to save their cherished friends.  Hell, plenty of famous/powerful people have bodyguards whose whole job is to "jump in front of the bullet."  Now maybe a Secret Service officer doesn't have enough love for his protectee to make the spell work, but within the novels I'm sure Harry, Ron, and Hermione would have been willing to sacrifice themselves for the others at any point, and that certainly would have been out of love.  Now, I'm not saying that everyone has people sacrificing their lives for each other everyday, but wouldn't that kind of protection spell still be fairly commonplace?  Especially during a time of strife, like during Voldemort or Grindelwald's rise and reign?  It seems like the more dangerous the era, the more often people would be making this kind of sacrifice.  Why would this kind of spell be so rare, given how natural the impulse to protect your loved ones is?

While answering another question I mentioned the love protection spell from Harry's mom, which got me thinking, since this spell is so unique and no one understands it, does that mean not a single person in the entire history of wizards is known to have died for someone because of love and then have created a protection spell for that person?  No parents, spouses or really close friends in the history of everything self-sacrificed for a loved one?  Did JKR create a loveless universe, where love was as miraculous and rare as the fact that Harry is the only person to survive Avada Kedavra?


Given: $f: X → Y, x\in X$, and $f$ is continuous at $x$, $f$ is continuous on $X$.  Prove that $f$ is continuous on $X$ if and only if for each open subset $V$ of $Y$, $f^{-1}(V)$ is an open subset of $X$.

Let $ X \subset \mathbb{R}$ be a non-empty, open set and let $f: X \rightarrow \mathbb{R}$ be a continuous function. Show that the inverse image of an open set is open under f, i.e. show:  If $M \subset \mathbb{R}$ is open, then $f^{-1}(M)$ is open as well.  I think that this should basically follow from the definitions, but I'm still having some troubles with the proof.  Suppose $M \subset \mathbb{R}$ is open, then it follows that $\forall z \in M, \exists r > 0: K_r(z) \subseteq M$  Since f is continuous it follows for each $x_0 \in X$ that for each $\epsilon > 0 ,\exists \delta > 0 : |f(x)-f(x_0)|< \epsilon, \forall x \in X: |x-x_0|<\delta$  Now I need to show that $f^{-1}(M)$ is open, so that for each $z \in M, \exists r>0: K_r(f^{-1}(z_0)) \subseteq f^{-1}(M)$  I'm not sure how to prove this. I guess since $z = f(x)$ and since M is open we have that $\exists r>0:\{z:|z-z_0|<r\}\subseteq M$. And since f is continuous: $|f(x)-f(x_0)| = |z-z_0|< \epsilon$ for all $|x-x_0|<\delta$, but since $|x-x_0|=|f^{-1}(z)-f^{-1}(z_0)|<\delta$ it somehow follows from that that $f^{-1}(M)$ is open?!  Which is just horrible and probably completely wrong. But I'm really confused from all the definitions right now and need some help please.


I am writing a letter to some family members and it is a thank you to a whole family. Would it be written as Dear Smiths,?  Do I need an apostrophe, so it is Dear Smith's? What if it ends in an s like the surname 'Stokes'? Do you write Dear Stokes' or simply Dear Stokes, because Dear Stokeses seems wrong? Thank you very much.

When pluralizing family (last) names that also happen to be common English words, does the pluralization follow the same rules as the common word?  For example, "the Smith family" can be pluralized as "the Smiths", but what if the family name is "Wolf" or "Fish"?  Would the correct pluralization be "the Wolfs" or "the Wolves"?


I know this types of error already has been answered. But i am not able figure out the cause of error. what i am trying to accomplish is to add button dynamically into fragment from a button click which is in main activity. please help me. i am new to android development,  public class MainActivity extends AppCompatActivity {  Button add; Fragment f; LinearLayout ll; View v;  @Override protected void onCreate(final Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_main);     add = (Button) findViewById(R.id.addButton);      add.setOnClickListener(new View.OnClickListener() {          @Override         public void onClick(View v) {             f = (ButtonFragment) getFragmentManager().findFragmentById(R.id.buttonLayout);             //if (f != null) {                 v = f.getView();                 ll = (LinearLayout) v.findViewById(R.id.buttonLayout);                 Button dummy = new Button(v.getContext());                 LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(70, 70);                 dummy.setLayoutParams(layoutParams);                 ll.addView(dummy);             //} else {               //  System.out.println("View is null");             //}          }     }); }   }   This is the fragment class  public class ButtonFragment extends Fragment {   @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {     View rootView = inflater.inflate(R.layout.fragment_button, container, false);     return rootView; } @Override public void onViewCreated(View view, Bundle savedInstanceState) {    System.out.println("View created"); } }   this are the error code     11-25 23:15:15.442 987-987/com.example.nekib.dynamiclayoutdemo   E/AndroidRuntime: FATAL EXCEPTION: main                                                                                Process: com.example.nekib.dynamiclayoutdemo, PID: 987                                                                                java.lang.NullPointerException: Attempt to invoke virtual method   'android.view.View android.app.Fragment.getView()' on a null object   reference                                                                                at   com.example.nekib.dynamiclayoutdemo.MainActivity$1.onClick(MainActivity.java:33)                                                                                at android.view.View.performClick(View.java:4780)                                                                                at android.view.View$PerformClick.run(View.java:19866)                                                                                at android.os.Handler.handleCallback(Handler.java:739)                                                                                at android.os.Handler.dispatchMessage(Handler.java:95)                                                                                at android.os.Looper.loop(Looper.java:135)                                                                                at android.app.ActivityThread.main(ActivityThread.java:5254)                                                                                at java.lang.reflect.Method.invoke(Native Method)                                                                                at java.lang.reflect.Method.invoke(Method.java:372)                                                                                at   com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)                                                                                at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I'd like to add a header containing of a picture (aligned left with text), multirow text and a picture (aligned right with the text). I found fancyhdr which has an inacceptably compilcated documentation, I hope someone has experience. I'd like the complete header to have a blue background spanning over the full textwidth (therefore putting pictures in lhead and rhead doesn't seem to be useful. My markup looks like this:  \usepackage{fancyhdr} \definecolor{arylideyellow}{rgb}{0.91, 0.84, 0.42} \newcommand{\myboxheader}[1]{{\color{blue} #1}} \newcommand{\mybox}[1]{\fcolorbox{gray}{arylideyellow}{#1}} \pagestyle{fancy} %\lhead{\colorbox{blue}{\includegraphics[height=1cm]{logo1.png} }} \chead{\makebox[\textwidth]{\colorbox{blue}{\includegraphics[height=1cm]{logo1.png} \hfill my multiline header (multiline with \newline or \\?) \hfill \includegraphics[height=1cm]{logo2.png} }}} %\rhead{\colorbox{blue}{\includegraphics[height=1cm]{logo2.png} }} \cfoot{I don't care for the footer so far!}  \begin{document} ... \end{document}   It is not moving the two pictures sufficiently to the left and to the right so that they are in line with the text borders.  I checked questions like  or , but they all assume that one can understand the structure of this large set of variables which are put in insufficient relation to each other in the docs, which doesn't apply to me...  Addendum from the comment:    Screenshot of the gap between logos A,B and the center part. I referred with "center part" to everything except the logos.

I'm trying to use LaTeX for creating corporate letters. What I have found is that there are many tools to write letters, but they are mostly focused on letters of more personal nature rather than corporate letters, in the sense that I can not find many ways to configure colored styles that are more common in corporate letters. What do I refer to? Something like this (taken from ):    This letter consists of two 'headers':   The orange header with the logo and some text (part of the corporate style) The contact / meta info of the letter (organization contact details, reference, etc).    In most examples and documentation (eg the ), it is explained how to set up textual letterhead, but not the header that forms part of the corporate style. So my question is: what is the proper way to do this? I have found similar information, for instance here:       But the problem is that they are not letter documents, and I feel these solutions are not the correct way to do this. Also, in a letter this header part is logically repeated on every page, and that is not the case in the samples either. I am also considering using the  for this top header (the orange part), but I am not sure if this is correct either.   What is the right way to set this up?


I just started a bounty for  but made a typo ("seem" instead if "seen").  How can I edit it?  If I can't, would it be an acceptable use of a flag to ask for it to be corrected?

I put up  over on SO with the assumption that the text would be formatted like it is for a question or answer.  I'm not really sure if I was incorrect in my assumption, or if I just formatted my text improperly, as I can't go back and edit what I put in.  Am I missing an obvious feature?  If not, would it be reasonable to request bounty-text edits—perhaps with moderator-approval to prevent abuse?  Edit: I was trying to use markdown to produce an unordered list as part of my bounty.  What you see in the link is a blob of text with dashes separating phrases


Alright so I installed the crouton Ubuntu thing on my Chromebook while following . After getting it installed it would not let me set a password and now I can't update the system so I'm wondering how to fix it. I'm kind of noobish at this.  This is what is displayed-  (precise)redeyeschivo@localhost-$ sudo password set [sudo] password for redeyeschivo:

When I'm about to install a program in the terminal it wants the password:  [sudo] password for xxx:   But when I start to type my password nothing happens. What should I do?


If $\Big|z^3+\dfrac{1}{z^3}\Big| \leq 2$ then prove that $\Big|z+\dfrac{1}{z}\Big| \le 2$ for a complex number $z$.   My attempt:We have:  $|z^3+\frac{1}{z^3}|=|(z+\frac{1}{z})(z^2+\frac{1}{z^2}-1)|=|(z+\frac{1}{z})||(z^2+\frac{1}{z^2}-1)|$  So for proving that we need to prove $|(z^2+\frac{1}{z^2}-1)|>1$ Which is really easy when $z$ is a real number but not when $z$ is complex.

Problem :  Let $z \in\Bbb{C}^{\times}$ such that $|z^3+\frac{1}{z^3}|\leq 2$. Prove that $|z+\frac{1}{z}|\leq 2$.  My approach : Since : $(a^3+b^3)=(a+b)^3-3ab(a+b)$ $\Rightarrow z^3+\frac{1}{z^3}=(z+\frac{1}{z})^3-3(z+\frac{1}{z})$ Now I don't know further about this problem whether or not this will help here. Please guide to solve this problem will be of great help, thanks.


I'm looking for how to get FTPS working properly via FileZilla Server on an Azure VM running Windows 2012.  I've opened port 990 and configured FTP over TLS in FileZilla.  I have opened port 990 in both the firewall and the Azure portal interface and still cannot connect.  I'm attempting to connect using FileZilla client using FTPS login.  Has anyone succeeded in configuring an FTPS server (other than IIS) on an Azure VM?  I need separate user accounts and the ability to assign separate folders to save files to.  Any ideas?

I need to access an FTPS server (vsftpd) on a vendor's site. The vendor has a firewall in front of the ftps server. I have a firewall in front of my FTPS client.   I understand that ports 990, 991 and maybe 989 need to be opened up for control traffic.  I have some questions:   When looking at it from the vendor's firewall perspective, should these ports be opened up for both inbound and outbound traffic?  What about ports for the DATA channel? Do I have to open all ports above 1000? Should I do it for both inbound and outbound traffic ?


Need guidance on this proof by mathematical induction. I am new to this type of math and don't know how exactly to get started.   $$ 1^3  +  2^3  +  3^3  +  \ldots  +  n^3  =  \left[\frac{n(n+1)}{2}\right]^2 $$


How do I prove that the determinant is the only function that has the properties of the determinant (multilinearity, being alternating, $\det(I)=1$).  In my notes we started to prove it like: suppose there is another such function (say $g$)... But from then on I can't make sense of it.

How can I prove that the determinant function satisfying the following properties is unique:  $\det(I)=1$ where  $I$ is identity matrix, the function $\det(A)$ is linear in the rows of the matrix and if two adjacent rows of a matrix $A$ are equal, then $\det A=0$. This is how Artin has stated the properties.I find Artin's first chapter rough going and would appreciate some help on this one.


Given a connected subset $A$ of $\mathbb{R}^p$ and a continuous function $f:A\to \mathbb{R}$.  If I have points $b,c \in A$ and a point $x \in \mathbb{R}$ that satisfies $f(a) < x < f(b)$,  how do I show that there is a point $c \in A$ such that $f(c) = x$?

If $ f $ is a continuous mapping from a connected set to the real numbers and there exists a real number s that nothing maps to, then the image is either greater than or less than s. this is clear to me intuitively but I can't think of how to prove it.


This is an image of a 50 samples render of my scene. I know, low samples but no matter what samples I render it at the textures are always blurred.     This is my camera options.    And this is my render options. How do I un-blur these textures?

I unwrapped a simple plane and applied the following 80x80 pixel picture:    Yes, it's quite small. The problem is, the result is all blurry, like so:    How do I make it accurate to the pixel?


i don't have much knowledge about dns records and devops things. I'm just trying to achieve ;  I have an Ec2 instance on amazon. I create a CNAME record for and successfully redirected to ec2 instance.  I would like to know is it possible to subdomain to given port number for ec2 instance i mean; I have 2 node.js applications are running on my ec2 server one of them is listening to 80 port which is providing web content. CNAME record is just working fine with that application.  My other application is listening to 5575 port. i would like to have . that is point to ec2's 5575 port. is it possible to have something like that. I found SRV record thing but i'm not sure if it's correct record type for me.

This is a  about DNS/Hostnames resolution to IPs/Ports   Example 1  I'm running a web server on port 80 and another on port 87. I would like to use DNS so that www.example.com goes to port 87. How can I accomplish this using DNS only?  Example 2  I'm running a service on my server on a non-standard port. How can I get clients to connect to this non-standard port automatically? Can I use DNS? Is there some application specific support where DNS could indicate the IP and Port?   Example 3  Do some application protocols specifically support hostname awareness, and allow special actions to be taken based on this information? Are there other questions on Server Fault that cover some of these?  Commandeering: This question was originally asking about running IIS and Apache on the same server, but the same concepts can be applied to any server software receiving connections from clients. The Answers below describe the technical problems and solutions of using DNS and application protocol support to assign a port number for a client to connect.


I have directory with rwx permission for current user, but he's unable to access it, why?  : sudo ls /usr/data/user-data  -lad drwx------ 9 andrew andrew 4096 May 17 11:13 /usr/data/user-data  : whoami  andrew  : ls /usr/data/user-data  ls: cannot access '/usr/data/user-data': Permission denied  : touch /usr/data/user-data/test touch: cannot touch '/usr/data/user-data/test': Permission denied   EDIT:  : sudo namei -lx /usr/data/user-data [sudo] password for andrew:  f: /usr/data/user-data Drwxr-xr-x root   root   / drwxr-xr-x root   root   usr drwxr--r-- root   root   data drwx------ andrew andrew user-data

I was trying to get the user nagios to have access a sub directory in another users home directory /home/alert/NagiosAlerts/.  I was going crazy setting permissions that should have been to high to get this work work (777 type stuff for testing) but was still getting permission denied doing simple touch tests. Started writing up a question here to ask and got linked to  which had the following in its answer:     The directory needs to be searchable to allow users to enter it or its subdirectory "project"   So that is what fixed my issue me as well. I change the group of the folder /home/alert and set the group permissions to --x and I am now able create files in /home/alert/NagiosAlerts/.  Why did I have to assign those rights in the parent directory /home/alert? I would have figured the rights in /home/alert/NagiosAlerts would have been fine?  If I touch /home/alert/NagiosAlert/file should it only matter about the permissions on NagiosAlert? Why would alert matter?


I'm trying to prove the following  $$ \sum_{r=0}^{n}(r+1) \binom{n}{r} = (n+2)2^{n-1} $$  using the identity $$ \sum_{r=0}^{n} \binom{n}{r} = 2^{n} $$  but I'm not able to. This is what I did so far,   $$ \sum_{r=0}^{n}(r+1) \binom{n}{r} = (1) \binom{n}{0} + (2) \binom{n}{1} + ... + (n+1) \binom{n}{n} $$


In George R. R. Martin's A Game Of Thrones, there is a moment when one character says the following words:     “So the slaver has become a spy. I would rather he become a corpse.”   Now, I understand the general meaning of it: that the speaker would prefer that person to be dead rather than spying around. What I don't understand is the exact grammar behind the second sentence of the example below.  From what I know, rather is an adverb, so the main clause doesn't have a predicate and technically is incomplete. And since there is a common language structure "pronoun + would rather + verb1 (+ than + verb2)", like I would rather die (than do it), I assume that in my example is used some specific shortened form of a more verbose construction, like it's the case with would that i could. Am I correct? If so, then what is the full form of it?  Also, I'm not entirely sure in what tense become is used in the second sentence. Is it a subjunctive present form, or some shortened form of present perfect that was used in the first sentence, or maybe something else entirely?  And one more thing. When "would rather" is used like in the example above, does it imply some, I don't know how to say it, temporal reference, i.e. when the action described by the verb that follows it should happen or should have happened? In other words, in my example, does the speaker express a wish to see that person dead already or simply want him to die at any time in the future?  Thank you!

What is the difference between:   The company would rather each employee be provided with ID card.  The company would rather each employee were provided with ID card.


I'm new to ubuntu. Recently I installed ubuntu. Hard drive partitioning for ubuntu was done during the installation process. Now I can't go to hard drives giving an error message that it can't mount hard drives. I went through online help and it was said to restart windows after booting from GRUB. But from GRUB even though I select windows 10 loader windows does not boot. Basically I have two problems.

I installed Windows on my computer, followed by an installation of Ubuntu. However, now I'm unable to boot into my Windows install.  What can I do to fix this?


It has been 10 weeks since I submitted my revised manuscript for minor revisions. The status of the article is "revision submitted to journal" since 6th Sept (and it is now 14th Nov). I am applying for a grant and really want to include this article in my CV, is it rude to write to the editor to find out what is going on? I am worried that my article has somehow gone under the radar and the editor has completely forgotten about it. Just wondering do they get alerts if they haven't responded to a submission for too long?

What steps does a manuscript typically go through from submission to publication (or rejection) in a typical journal? How are these steps referred to, in particular by editorial systems, and how long do they each typically take?  Note that this question is about the typical situation and hence not about:   Journals with an atypical workflow, e.g. those that allow for an instantaneous reviewer–author interaction. Exceptional steps or rare occurrences such as withdrawal or .   This is a canonical question on this topic as per . Due to its nature, it is rather broad and not exemplary for a regular question on this site. Please feel free to improve this question.


I want to ask if it is possible to install Windows 8.1 on a Ubuntu machine making it dual boot ?  If yes, please also tell the procedure.  If no, please tell any workaround for installing latest high end graphics windows games on Ubuntu machine. (They do not work in virtualbox and wine).  I searched very much on Internet but can not find any satisfactory solution. Please help.

I have Ubuntu on my laptop. Now I want install Windows 7 in a dual-boot. How can I do this? I can't lose my Ubuntu files, and I'm afraid that I might break . Go  for UEFI only!


I am in general confused about the assumptions of linear regression and on whom are those assumptions taken to be and what are the consequences of these assumptions on the validation procedure for the regression model.  Can someone help in this regard.

What are the usual assumptions for linear regression?   Do they include:   a linear relationship between the independent and dependent variable independent errors normal distribution of errors homoscedasticity   Are there any others?


I have my computer and it doesn't have a separate video card. Do i need a video card to install Photoshop? Or is there any version of Photoshop that doesn't require to a separate video card?

I'm looking to buy a laptop (for a spare) and I'm not ready to spend the amount I did on my first one. The machine will only be used for photo editing. Should I go for the dedicated graphics card or faster CPU? Has there been greater performance differences when using Photoshop with a better/more CPU or GPU?  Specifically I'm asking whether a dedicated GPU will offer a substantial jump in the performance of Photoshop and Lightroom over an integrated one, when compared with a faster CPU.  Note: the question is about comparing hardware performance specifically of the GPU & CPU when using PS & LR (I've done my own tests & research regarding SSDs, RAM, monitors etc. I'm not looking for help in buying a computer, I'll do that on my own...) I'm asking the question here because I assume many people using this site have either experienced or researched the topic and I would like to see what the results were


This is new behavior tonight: both the reputation and inbox counters are stuck in time.  My reputation notification indicator seems to be stuck at a particular value; it shows "+52" regardless of what I do.  In the following screen shot you can see that these notifications are not new (they were an hour ago, but I've opened that notification thingy several times now):    After I click on the notification it goes away on the current page -- but on the next page-load it's back, on multiple sites.  The same thing happens with the inbox notification; after I clicked that and went to a new page the red 4 was back.  This happens in Firefox (31.0) and Chrome (36.0.1985.125) on Mac OS 10.6, and I'm also seeing it in Chrome on my Android phone.  Further, while investigating this and writing this post, I got two new rep updates -- and they neither changed the count nor show up in the drop-down:    (I took the first screen shot after these events occurred.)  I think I've seen reports of the first problem -- the notice not dismissing -- before, but can't find them.  I can't remember seeing reports of the second problem.

This was asked before too. .  Currently I am facing the issue of appearance of reputation notification in above toolbar.  I can see the reputation notification, for every page refresh even after clicking and viewing the notification.  current browser: Chrome Version 36.0.1985.143 m


Give a constructive proof to show that for all $n \geq 1$ ,  $\sum\limits_{i=1}^n i^3 = (\sum\limits_{i=1}^n i)^2$  Observe that $(n+1)^4 - n^4 = 4n^3 + 6n^2 + 4n + 1$ .    Now, the two following equalities are obvious:  $\sum\limits_{i=1}^n i^3 = 1^3 + 2^3 + 3^3 + ... + n^3$  $(\sum\limits_{i=1}^n i)^2 = (1 + 2 + 3 + ... + n)^2$  And they are both obviously equivalent given the first few test cases:  $\sum\limits_{i=1}^n i^3 = A(n)$   $A(1) = 1^3 = 1$                 $A(2) = 1^3 + 2^3 = 1 + 8 = 9$ $A(3) = 1^3 + 2^3 + 3^3 = 9 + 27 = 36$   $(\sum\limits_{i=1}^n i)^2 = B(n)$   $B(1) = (1)^2 = 1$ $B(2) = (1 + 2)^2 =9 $ $B(3) = (1 + 2 + 3)^2 = 36$   Now, I am thinking of finding the closed-forms for both functions in the hopes that they are indeed the same. Then I would prove those closed forms to work by induction. But:   I don't know if that would be a sound way to do it. I don't know if this would even qualify as constructive, as the question requests.   As you may tell, I am no math major. I am a Computer Science major, though. This is a computing fundamentals class. I took discrete 1.5 years ago, so my knowledge is about as fresh as a litter box. I've been in quite a rut for a few hours over this.

How can I prove that     $$1^3+ 2^3 + \cdots + n^3 = \left(\frac{n(n+1)}{2}\right)^2$$    for all $n \in \mathbb{N}$? I am looking for a proof using mathematical induction.  Thanks


I want a model of a quadcopter and, thus, I need the transfer function of the motor.   Any suggestions on how to do it will be very helpful for me. Thanks.

I am building a quadrotor and want get a reasonable estimate of the dynamics (voltage to rpm transfer function) of the motors. I am wondering:  1) Is the transfer function for a typical BLDC 1st or 2nd order?  2) Does kv rating relate to any constants in the transfer function?  The motors I have are 3-phase 2300kv with 12 windings, but other than that I have had a hard time finding useful information about them.


When I add this text:  The pdpotri routine computes the inverse of a real symmetric or complex Hermitian positive definite distributed matrix $sub(A) = A(ia:ia+n-1, ja:ja+n-1)$ using the Cholesky factorization $sub(A) = UH*U or sub(A) = L*LH$ computed by pdpotrf.   to my .tex, I get this:  LaTeX Warning: `h' float specifier changed to `ht'.   If I remove it, it goes away. If I remove only the match mode (the dollar signs), the warning is still alive. The document has sections and subsections, if that helps. It also has many math inside it. I am trying to produce a minor example...  How to get rid of this warning?    EDIT  Check first comment of Gonzalo!

I'm new to LaTeX and trying to understand the reason why I'm getting the warning:  `h' float specifier changed to `ht'   I'm not attempting to change the float property of anything - the warning is showing up if I attempt to simply encapsulate some words in quotation marks:  ``highly distributed''   As far as I'm aware, there's no open sections anywhere and the file seems to render properly. So realistically it doesn't matter if the issue gets solved or not; but I'd like to know the reason I'm getting the warning.  Thanks in advance.


I am writing code for my deep learning project and when getting error while running facial detection.  I am building facial recognition system and I am getting error      NameError: name 'x' is not defined    while running the code, but I am not able to find root source of these problem.  import numpy as np import cv2  CascadeClassifier = cv2.CascadeClassifier(r'C:\Users\ESEC\Desktop\opencv\aditya\cascades\haarcascades\haarcascade_frontalface_alt2.xml')  cap = cv2.VideoCapture(0)   while(True):     # Capture frame-by-frame     ret, frame = cap.read()        gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)      faces = CascadeClassifier.detectMultiScale(gray, scaleFactor=1.5, minNeighbors=5)      for (x, y, w, h) in faces:         print(x,y,w,h)         roi_gray = gray[y:y+h, x:x+w]          roi_color = gray[y:y+h, x:x+w]          img_item = 'image.png'         cv2.imwrite(img_item, roi_gray)     # Our operations on the frame come here      color = (255,0,0) #BGR 0=255      stroke = 2       end_cord_x = x + w      end_cord_y = y + h      cv2.rectangle(frame, (x, y), (end_cord_x, end_cord_y), color, stroke)      # Display the resulting frame     cv2.imshow('frame',frame)     if cv2.waitKey(20) & 0xFF == ord('q'):         break       # When everything done, release the capture      cap.release()      cv2.destroyAllWindows()   It should be running smoothly and should be showing rectangle around the face but I am getting this following error.  File "camera-test.py", line 34, in <module> end_cord_x = x + w NameError: name 'x' is not defined

What exactly are the Python scoping rules?  If I have some code:  code1 class Foo:    code2    def spam.....       code3       for code4..:        code5        x()   Where is x found?  Some possible choices include the list below:   In the enclosing source file In the class namespace In the function definition In the for loop index variable Inside the for loop   Also there is the context during execution, when the function spam is passed somewhere else. And maybe  pass a bit differently?  There must be a simple reference or algorithm somewhere.  It's a confusing world for intermediate Python programmers.


Let us consider a linear regression model $\underline{Y} = X \underline{\beta} + \underline{\epsilon}$, where X is an $n \times p$ matrix, rank($X$) = $p$, $E(\underline{\epsilon}) = \underline{0}$, $D(\underline{\epsilon}) = \sigma^2 I$.  (Here, $E(.)$ stands for expectation, $D(.)$ denotes the variance covariance matrix and $I$ is the $n$-th order identity matrix.)  Let the $n \times n$ hat matrix $H$ be defined as $H = \big( \big( h_{ij} \big) \big) = X (X^{'}X)^{-1}X^{'}$.  If $h_{ii} = 0$ or $1$ for some $i$, then how can I show $h_{ij} = 0$ for all $j \neq i$?

I am considering a linear regression model $Y_i = X_i^T \beta + \epsilon_i, i = 1,2,\dots,n$. where $X_i \in \mathbb{R}^p$. $\epsilon_i$'s are independent copies of random error $\epsilon \in \mathbb{R}^1$ with mean 0 and variance $\sigma^2$. We have the  hat matrix given by  $$ H = X^T (X^TX)^{-1} X$$ I am trying to show $h_{ij}^2 \leq h_{ii} h_{kk}$. I know that $$h_{ij} = X_i^T (X^T X)^{-1} X_j$$ and that $H^2 = H$ because it is idempotent. This gives me $\sum_{k=1}^n h_{ik}^2 = h_{ii}$ but I don't know how to prove $h_{ij}^2 \leq h_{ii} h_{jj}$.


if  (!Character.isDigit(payroll_no))  {     document.getElementById('field_117219').value ='We do not have your payroll number please email it to us')  }  else   {      Name = document.getElementById('field_115676').value;      document.getElementById('field_117219').value ="Appraisal Details for "+Name;       iframe_115667.location.replace('/sorce/apps/enh/asp/Appraisals.aspxgridname=Appraisals&Payroll_no='+Payroll_no);   }

What's the cleanest, most effective way to validate decimal numbers in JavaScript?  Bonus points for:   Clarity. Solution should be clean and simple. Cross-platform.   Test cases:  01. IsNumeric('-1')      => true 02. IsNumeric('-1.5')    => true 03. IsNumeric('0')       => true 04. IsNumeric('0.42')    => true 05. IsNumeric('.42')     => true 06. IsNumeric('99,999')  => false 07. IsNumeric('0x89f')   => false 08. IsNumeric('#abcdef') => false 09. IsNumeric('1.2.3')   => false 10. IsNumeric('')        => false 11. IsNumeric('blah')    => false


I have a strange issue happening with my code below:    RestAPIHeader requestedBy = new RestAPIHeader("X-Requested-By", "test");    // Act   RestAPIRequest req = prepareLoginRequest(USER_NAME, PASSWORD);    // The following returns a list of header objects such that one of them   // is "X-Requested-By: test"   List<RestAPIHeader> headers = req.getAllHeaders();    boolean foundRequestedBy = false;   for (RestAPIHeader h : headers) {       Log.d(LOGTAG, "Header: " + h.toString());       if (requestedBy.equals(h)) {           foundRequestedBy = true;       }   }    // Assert   assertNotNull(req);    // This assertion passes   assertTrue(foundRequestedBy);    // This assertion fails   assertTrue(headers.contains(requestedBy));   What bothers me is that it seems like headers.contains(requestedBy) should be equivalent to foundRequestedBy in this code (since this is the result of a simple search). However, as I mention in the comments, it doesn't actually return the same value. It almost seems as though contains isn't using equals(), but rather ==. Can someone point out why this is the case?  Edit:  The equals method of the RestAPIHeader class is as follows:    public boolean equals(RestAPIHeader aOther) {     return mPropertyName.equals(aOther.getHeaderName())       && mPropertyValue.equals(aOther.getHeaderValue());   }

I ran into an interesting (and very frustrating) issue with the equals() method today which caused what I thought to be a well tested class to crash and cause a bug that took me a very long time to track down.   Just for completeness, I wasn't using an IDE or debugger - just good old fashioned text editor and System.out's. Time was very limited and it was a school project.  Anyhow -   I was developing a basic shopping cart which could contain an ArrayList of Book objects. In order to implement the addBook(), removeBook(), and hasBook() methods of the Cart, I wanted to check if the Book already existed in the Cart. So off I go -  public boolean equals(Book b) {     ... // More code here - null checks     if (b.getID() == this.getID()) return true;     else return false; }   All works fine in testing. I create 6 objects and fill them with data. Do many adds, removes, has() operations on the Cart and everything works fine. I read that you can either have equals(TYPE var) or equals(Object o) { (CAST) var } but assumed that since it was working, it didn't matter too much.  Then I ran into a problem - I needed to create a Book object with only the ID in it from within the Book class. No other data would be entered into it. Basically the following:  public boolean hasBook(int i) {     Book b = new Book(i);     return hasBook(b); }  public boolean hasBook(Book b) {     // .. more code here     return this.books.contains(b); }   All of a sudden, the equals(Book b) method no longer works. This took a VERY long time to track down without a good debugger and assuming the Cart class was properly tested and correct. After swaapping the equals() method to the following:  public boolean equals(Object o) {     Book b = (Book) o;     ... // The rest goes here    }   Everything began to work again. Is there a reason the method decided not to take the Book parameter even though it clearly  was  a Book object? The only difference seemed to be it was instantiated from within the same class, and only filled with one data member. I'm very very confused. Please, shed some light?


Which of the following is correct? If A is correct why is B incorrect?  I am stumped, This sentence has popped up in my Hong Kong English class, don't know how to sort it out. Why does the one sentence sound awful yet is essentially the same:     A) What doesn't she know how to cook?   B) What does not she know how to cook?   C) What does she not know how to cook?

I have found multiple questions touching on this but not a single one that has a comprehensive answer. The information is all there but in little bits.     etc.   Exactly why is "Do not you sleep?" ungrammatical (except in poetry/with artistic license)? I understand that not can't contract after you: "Do you not sleep?" because not can only contract after a verb, and that it always does after do: "Don't you sleep?" but why does it (why must it) contract if it's placed after the verb in a question?   Don't you sleep? (common form) Do not you sleep? (ungrammatical) Do you not sleep? (less common form)


I seem to be experiencing recurring memory issues with Netty 4. My app queries Minecraft servers for information and updates a database with that information. Currently it creates 300 connection requests every 10 seconds and sends packets if those connections are successfully completed.  A previous iteration of my querying app used Netty 3.2.5 and it ran for months on end nonstop with no issues. With Netty 4 however, it only runs a few hours before exhausting all available resources. Here is a screenshot of the memory sampling over a JMX connection.    As we can see, io.netty.channel.ChannelOutboundBuffer$Entry is using up a large amount of memory. Any idea how to go about troubleshooting this? I'm available to provide code if you guys need. Thanks!  Edit: This is not a duplicate of "How to find a Java memory leak". This has to do with Netty specifically, and I'm not trying to find out how to discover a memory leak - I've already discovered one with Netty.

How do you find a memory leak in Java (using, for example, JHat)? I have tried to load the heap dump up in JHat to take a basic look. However, I do not understand how I am supposed to be able to find the root reference () or whatever it is called. Basically, I can tell that there are several hundred megabytes of hash table entries ([java.util.HashMap$Entry or something like that), but maps are used all over the place... Is there some way to search for large maps, or perhaps find general roots of large object trees?  [Edit] Ok, I've read the answers so far but let's just say I am a cheap bastard (meaning I am more interested in learning how to use JHat than to pay for JProfiler). Also, JHat is always available since it is part of the JDK. Unless of course there is no way with JHat but brute force, but I can't believe that can be the case.  Also, I do not think I will be able to actually modify (adding logging of all map sizes) and run it for long enough for me to notice the leak.


20.04 seems to have lost the ability to change desktop icons by right clicking them and changing the icon in the Properties window. You can still see the new icon in the files, but it does not update on the desktop. Does any one know a workaround?

In Ubuntu 20.04, on the desktop, there is a number of actions I wish I could do, such as, by order of importance :  use keyboard shortcuts such as select all, copy / paste. use drag & drop with icons deactivate the "mouse over" highlight, and restrict the clicking area to only the icon, not the surrounding square  To put it simply, I'd like to have the exact same features as offered by the desktop of Ubuntu 18.04 (probably related to a specific version of GNOME, and not Ubuntu itself). Am I missing something obvious here? I actually see no reason why those actions are removed or deactivated on the desktop, since they all work in any Nautilus window.


What I remember was that it had (its really vague but its all I got):   Three or four main characters, one of them a girl, two of them guys, then there was like a dad or grandpa helping them.    They have magic stones they use to capture creatures, or they live inside the gemstone things. The main character had some kind of blue and white bear/beast creature called "furrock" or something he had horns too. The girl has some kind of rhino with nature powers, so it was covered in leaves.  The main characters' dad was probably the evil guy; I can't remember   It was from around 2009-2011, I think. It was on Netflix when I saw it, but since then its been deleted for a while.    I know it is not Huntik.  I'm just saying that cause that's what a lot of the searches thought it was but it's not. I know this isn't a lot but if someone knows anything it would be really helpful because I keep remembering and forgetting what its called.

What is the name of the anime TV show where a boy can summon beasts with crystals/gems. It was on SABC 2. There was also a boy that could summon a purple turtle . I think the gems were blue, green, and red.


What is wrong with below code?  SELECT  first_name, last_name FROM    employees UNION ALL SELECT  first_name, last_name FROM    dependents ORDER BY  last_name LIMIT 6 OFFSET 1;   Even a simple query with LIMIT doesn't seem to be working :  SELECT  first_name, last_name FROM    dependents ORDER BY  last_name LIMIT 6 OFFSET 1;      Getting this error repeatedly: ORA-00933: SQL command not properly   ended

Is there a way to make an Oracle query behave like it contains a MySQL limit clause? In MySQL, I can do this: select *  from sometable order by name limit 20,10  to get the 21st to the 30th rows (skip the first 20, give the next 10). The rows are selected after the order by, so it really starts on the 20th name alphabetically. In Oracle, the only thing people mention is the rownum pseudo-column, but it is evaluated before order by, which means this: select *  from sometable where rownum <= 10 order by name  will return a random set of ten rows ordered by name, which is not usually what I want. It also doesn't allow for specifying an offset.


I have both Ubuntu 12.04 and Windows 7 and dual booting. Ubuntu has 10GB of space and I'm running out of space. I want to increase this to 100GB, so I went to the Windows disk manager, it shows 100MB FAT16, 14GB recovery NTFS, 540GB OS NTFS. There are no partitions shown for Ubuntu/Linux in either the Windows disk manager or gparted. I used Windows disk manager to free up 100GB of space on my hard drive, is there a way to transfer my installed Ubuntu onto the new partition? Apparently, my existing install must be on Wubi, though I don't recall installing it there.

I have installed Ubuntu on my D: partition using Wubi. Is there any way in which I can remove my Windows from C: drive and move my existing Ubuntu installation to C: drive and make it a regular install.


In Naked Gun 33 1/3: The Final Insult (1994), Scene where Frank tries to take the  gun out of his pouch, but it was not there. Then he thinks past what  really happened to his gun. While thinking this effect used.    What is this effect called ?

In , Jyn Erso remembers her childhood days.   Her childhood/past days were shown with some effects like characters talking with a low voice with echo, with high background music, slow motion (not very slow) and shaky camera.   What is the name of this effect for showing past days in movies?


Do the end points of a domain come under critical points? I know we say critical point is a point where the derivative is zero or the derivative doesn't exist.   For example: $$ f:[0,\pi] \to [-1,1], f(x) = \sin(x).$$  Does this have 1 critical point or 3 critical points (0 and $\pi$ included) ?  NOTE: This question is limited to only Single Variable Functions.  Although I really would love an insight to this for Multivariable as well.

Given that an extreme value can only occur at a critical point and in the following case $$f(x) = \frac{1}{x} \quad [1,4]$$ we definitely have two absolute extreme values (maximum and minimum), are $x = 1$ and $x = 4$ critical points?  If so, what is the reasoning for that: the fact that they are in the domain of $f$ and they are not differentiable at those points?  Is my reasoning correct?


I am a Bangladeshi citizen and came on April 18th, 2017 to watch a football match in Spain. My spanish Schengen visa expires (today) on April, 21th 2017 and I am currently travelling to Germany from Spain by car, but I am still in Spain now. My German Schengen visa starts from April 22th, 2017 and is valid for a year, but I want to go back to Bangladesh on April 30th, 2017.  So do I need to leave the Schengen area today and come back tomorrow to Germany or does the German visa allows me to remain in the Schengen area?

If I have a Type C visa from the Norwegian embassy valid for February 9-28, and my Type D national visa from the German embassy valid from March 1 - August 31, 2017, do I need to leave/fly out of the Schengen area on the 28th and fly back on the 1st day of March?


I've been trying to do: $mydb = new wpdb(SQL Database info);  Is there a way to check whether the database connection was established? It doesn't seem to be working since $mydb->get_results(query) doesn't return anything, but I get no errors so I don't know what is wrong.

I want to connect wpdb to another database. How do I create the instance and pass it the database name/username/password?  Thanks


This is a view of the badge description and checkmark for a specific badge (say, ):    Here is the same badge description from the :    Could we adjust the vertical alignment of the checkmark in the former display to match that of the second? I suspect adjustments would have to be made for both the checkmark and the badge.   As a side-note: Why would there be a period at the end of the first display, but not the second?

At :    At :    The little green check mark is slightly too high in the second image.  Please just lower it a bit.    Another instance of bug found on :      Produced on:   Windows 8.1 Chrome V 47.0.2526.111 with default settings   Mac OS X El Capitan Chrome V 47.0.2526.111 with default settings Mac OS X El Capitan Safari V 9.0.2 (11601.3.9) with default settings Win 7, Firefox 62.0     The issue is still here after a long time, I would like to hear if this is going to be fixed or not.


My daughter is now one and half year old and still refuses to eat anything. She seem to be satisfied by mother's milk itself.  Is it okay to remain on breastfeed alone this long, or should we try avoid/stop breastfeeding so that she tries/takes other food?

What signs can a baby show to indicate he/she is ready for weaning?  What does a parent look for to determine the right timing for this for baby, mom and family?


So I'm trying to insert data into my SQLite database through a HTML form. I want to use prepared statements and so far I have managed this:  <form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>"> Title of the post:
 <input type="text" name="title">
     Post text:
 <textarea name="body" rows="5" cols="50"></textarea>
     <input type="submit" name="submit" value="Post!">  </form>   <?php  $user = $_SESSION['user']; $title = $_POST['title']; $body = $_POST['body'];  if(isset($_POST["submit"])){  try { $conn = new PDO("sqlite:../ex1"/*, $username, $password*/); $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);  $q = $conn->prepare("INSERT INTO posts (user, title, body) VALUES ($user, ?, ?");  $q->bindParam(':title', $title); $q->bindParam(':body', $body);   $q->execute($title, $body);   echo "done";   For some reason this doesn't work, but this code does:  $user = $_SESSION['user']; $title = $_POST['title']; $body = $_POST['body'];  $sql = "insert into posts (user, title, body) values ('" . $user . "', '" . $title . "', '" . $body . "');"; echo '
';  var_dump ($sql);  $conn->exec($sql);   Why is this? I would like to use prepared statements if possible.

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening?


I recently installed Sublime Text 2 on my Ubuntu 12.04. The problem is that whenever I open it, by default it opens up to two files: sublime.desktop and defaults.list. Also, whatever preferences I try to set aren't saved and I always get the default configuration (with these two files opened) every time I start it up. This wasn't the case with Sublime Text 1. It used to save my preferences and open on my last opened files. Why is this happening? How can I make it save my preferences as Sublime Text 1 did?

I installed Sublime Text 2 the following way, but what I do not like about it is that I have to run it as sudo to save the user settings files.  Any ways around this?  Thanks,  Colin  sudo add-apt-repository ppa:webupd8team/sublime-text-2 sudo apt-get update sudo apt-get install sublime-text


How can I use /testfor to see if someone is holding a diamond in their main hand?

This question was recently split into different questions for each workaround. See   meta posts for more information.   Can you use NBT tags in commands? I’ve tried commands that normally work in Java Edition like: give @s minecraft:planks 30 1 {display:{Lore:["Wooden planks"]}} give @s stone_pickaxe{Unbreakable:1b} give @s item_frame{EntityTag:{Invisible:1b}} summon villager ~ ~ ~ {Offers:{Recipes:[{buy:{id:"emerald",Count:5b},sell:{id:"diamond_sword"}}]}} summon tnt ~ ~ ~ {Fuse:20s}


I'm now trying Ubuntu live from a flash drive. I kind of like it, but at the same time I paid a lot for my Windows 7.  Can someone explain me what will cause/happen if I keep both of them? I heard something about the disk split (partitioning) or something. All I want to know is what happens with my 1TB hard drive. Will my documents still be there?

I'm using windows 7 right now. I want to install Ubuntu with dual boot. Is is safe? And does the process go safely?


Some people say that dark-energy density remains constant in an expanding universe. However this is something that's still rather hypothetical. It's rather atypical too, in that we have no examples of non-conservation of energy. If you move towards the $E=hf$ photon it appears blue-shifted, but it hasn't actually gained any energy. It hasn't changed at all, instead, you changed. If you drop a brick, gravity converts potential energy into kinetic energy. But it doesn't create any energy. It doesn't do work on the brick, instead you do work on the brick when you lift it up. In similar vein the ascending brick doesn't lose any energy. Nor does the ascending photon. See Einstein talking about  in the digital papers hosted at Princeton. Note that he doesn't say light changes frequency as it climbs out of the gravitational field. He says it's emitted at a lower frequency. There are no perpetual motion machines.   However some people say things like "any reasonable definition of energy that has been found leads to non-conservation in many GR scenarios". Only I don't know of any example of non-conservation of energy. Can you provide any? Either in a GR scenario, or in any other scenario?  I will award a 200-point bounty on this question. I will award it to the answer that I think is the best. If I don't much like any of the answers, I will still award the bounty to one of them.   Edit: now the question has been closed I have to withdraw the offer of a bounty I'm afraid. Apologies to those who have answered.

Is the law of conservation of energy still valid or have there been experiments showing that energy could be created or lost?


I have a file named diario.sh that I run manually using ./diario.sh The script file contains the following: #!/bin/bash cd /home/etapa/Scripts echo "@CDRS_ETAPATOTAL.sql" | sqlplus -s ooperadores/ooperadores@OOPERADORES | while read output; do echo $output done  When I run it manually works fine but when I try to run it using crontab I get the following error: ERROR: ORA-12154: TNS:could not resolve the connect identifier specified   SP2-0306: Invalid option. Usage: CONN[ECT] [{logon|/|proxy} [AS {SYSDBA|SYSOPER|SYSASM|SYSBACKUP|SYSDG|SYSKM|SYSRAC}] [edition=value]] where <logon> ::= <username>[/<password>][@<connect_identifier>] <proxy> ::= <proxyuser>[<username>][/<password>][@<connect_identifier>]  ERROR: ORA-12162: TNS:net service name is incorrectly specified   SP2-0157: unable to CONNECT to ORACLE after 3 attempts, exiting SQL*Plus  The crontab entry is the following: 10 * * * * /home/etapa/Scripts/diario.sh > /home/etapa/Scripts/diario.log 2>&1  Please help me solve this problem.

/oracle/GR1/121/bin/sqlplus / as sysdba <<EOF >> $LOGFILE whenever sqlerror exit sql.sqlcode; set echo on; set serveroutput on; STARTUP; EXIT EOF   Already tried it with the path, but it hasn't worked.


I have on a few occasions in the past, downvoted a question and then after re-evaluation thought that it shouldn’t have been.  When trying to cancel the downvote or changing it to an upvote, I find that I cannot do that unless an edit is made.  Why is that?

I downvoted  and now really can't say why, so I wanted to remove my downvote. However, I get the message:  You last voted on this question yesterday Your vote is now locked in unless this question is edited  Why is this? I don't think I voted on it multiple times, and even when I did, I can change my mind, can't I?


I'm trying to understand this case.  Let's say I want to have a method which has a return type of List<T>.  public List<T> GetAllItems(string category) { ... }   I've been advised to use instead this header :  public IList<T> GetAllItems(string category) { ... }   Why so?  I've made some research and one answer could be flexibility meaning that the type could be changed if it's implementing the same interface. But the motivation had to do something with exposing the interface only to prevent changes (?), I didn't really understand it. So, again, why is it better to return IList instead of List?

Can anyone explain to me why I would want to use IList over List in C#?  Related question:


Let's say I have around 30k points of time series data with values ranging from 0 to 0.5. I have split this data into 5 buckets of 0.1 each which contains values within that range. I then plot these values with x axis being the bucket sizes and y axis being the number of values. I noticed that the distribution pattern depends on the size of the buckets. How do I know for sure what type of distribution my data follows? My knowledge in statistics is not very good and maybe evident from my question. Any help appreciated!

Suppose I want to see whether my data is exponential based on a histogram (i.e. skewed to the right).   Depending on how I group or bin the data, I can get wildly different histograms.   One set of histograms will make is seem that the data is exponential. Another set will make it seem that data are not exponential. How do I make determining distributions from histograms well defined?


Recently I felt that one feature is really required on . I am active user since I love Stack Overflow. I love to review questions and visit this  tab for each new questions. I felt many times that new users just posting their question without any code or whatever he/she has done. So contributor has to put some common comments every time. Some example I wrote as follow which I would like to have as quick comment. Every time contributor has to comment like:  Please, post your code.  What you have done so far?  Have you tried anything?  Please add the code where you are using xxx xxx xxx code or variables  Welcome to Stack Overflow, Have you visit once  and ? etc, etc...   There are many suggestions that we can take as an example but we can give feature to contributors who can comment easily using template.

I'm annoyed by down voters that don't explain why they down voted a question or an answer. Although, at the same time, I understand that they . I think there is a middle ground, though, where the voter can remain anonymous, while the poster can get aggregated feedback on ways to improve the post.  Rather than having to imagine what it might be like, the current stackoverflow engine can emulate this rather effectively with the use of comments and the up-voting of those comments (essentially saying "I agree"). So I thought I would give it a try. The only difference is that in this testing post, you will always see the list of "canned responses" where as in the complete version, it will most likely be hidden in a popup (e.g. when you hover over the score of an answer/question). To try it out, simply up or down vote this question (or one of its answers), and press the up arrow next to the comment which best describes why are voting that way. For example, if you hate this idea, give this a down vote, and then press the up arrow near -1: I don't like this idea.  In addition to retaining anonymity, this will also save time for the voter so that they don't need to write out the comment. This wouldn't be required, obviously, and there could be a default option selected don't leave a reason. In addition, there could be a custom option which allows you type exactly why you are down-voting this way. Depending on the final implementation, this could either simply be converted to a comment automatically prefixed with -1:  or +1:; or, to retain anonymity, it would be added to this same list that shows the canned responses and how many users have voted that way.  Here are some ideas for the canned responses:  Question:   +1: Well formatted and thought out question. -1: It doesn't seem like enough time was spent trying to solve this issue on your own. -1: I don't like this idea. (Could be especially useful on meta.stackoverflow.com feature-request.) -1: No prior research/work. (Idea from .) -1: Poor question. Please see . -1: Doesn't contain code. (This would be useful on stackoverflow.com. Idea from )   Answer:   +1: Concise. +1: Insightful. +1: Worked for me. -1: It's wrong. -1: Confusing. -1: Encouraging bad behavior (e.g. answering a question that shouldn't have been asked; see ).   I made this a community-wiki since there will probably be testing of up/down votes. Several of these canned responses have been taken from . This same idea was also .


No sound via headphones (headset)  I've recently started using Ubuntu (Dual boot with Windows 10) The earphone works on other devices/Windows without any issues. I've even tried to not boot up with earphones plugged in. Laptop: ASUS S56C The internal speakers work fine.  ALSA information (alsa-info-script):  alsa-base.conf:

I have a Dell Studio XPS 1647 and headphones do not work (though , internal speakers work like a charm) , I have dual boot Windows 7 and headphones work perfectly fine ...     I also tried -adding in options snd-hda-intel model=eapd probe_mask=1 position_fix=1.  I've experienced this with Oneric Ocelot and the latest Precise Pangolin (LTS).


Where can (should) I put my (bash) script so that it can be used (forever) by terminal or by a direct command: Alt+F2?  I know there is /usr/bin and /sbin & /bindirectories but when should I use between them?  Where should I put my script?

I am developing a set of scripts, which I want to be present for all users, when I set up a server. But I don't want them in the standard locations like /usr[/local]/[bin],[sbin] etc.  Is there some existing convention for where such scripts should be placed?


I want to install the whole package of apache2, MySQL, PHP and phpmyadmin at a time on my ubuntu 14.04. I want to install the package from terminal. How to do it?

I set up a new VPS instance of Ubuntu and am wondering what the easiest way is to get up and running with a basic LAMP stack (i.e. which packages are required, which configuration options need to be tweaked, if any, etc.).


I'm running Windows 8.1 on my laptop, and it is set to do nothing when the lid is closed.  However, I often notice that the fan gets very loud, and when I open the laptop I can see CPU usage suddenly drop from 70% to almost nothing. It seems that System process is using 30%+ CPU while the lid is closed, and then suddenly stops when I open it. What could cause this behavior?

I have noticed that from some time my system is freezing and its probably caused by the high CPU usage which is caused by the system process.  All applications I'm running is the Skype, TeamSpeak and Chrome so it definitely shouldnt eat that amount of CPU.  You can see the problem itself and running processes in the screenshot below:    Sometimes CPU usage is reaching 90%, but the average usage is like 40-65%.  My PC parameters:   Windows 8 (customer preview) Intel Core i3 - 2350M 8 GB RAM   I'd appreciate any help attempt! Regards.  --UPDATE--  As the user below posted a great answer, I have noticed that the process that is eating the most CPU in the system is called Arthurx.sys, simple google tells that it's a TPLink driver (an wifi adapter, I have bought like 2 weeks ago!) drivers has been installed from the Windows MSDN, but also tried to install the drivers from the attached CD, but it doesn't help. From the system start, it is using like 5% of the CPU only, but after 2-4 hours of working it is growing up and reaching 40-60% of the CPU usage.  Device name: TPLink WN722N


My secondary hard disk (internal SATA drive) which is an hard disk (not SSD) it stops spinning automatically after about a minute ... (a sound is heard from it as when I turned off) I want to stop this feature in windows 10 ! Every time when I access a file from it, it takes about 1-2 seconds to start (a sound is heard that starts rotating the discs) It is very annoying because sometimes it blocks cursive application functionality... Even if I set to 0 "Turn off Hard disk" in "Power option", nothing happens..., also I tried to set at 60 minutes or something, but the result is same, hard disk stop running after about one minute... I want the hard drive to run continuously, without stopping! Thanks in advance! Silviu

First off I did try the power options setting and it's on 'Never' but that did nothing. The drive still spins down after 15-20 seconds of not being used. I need it to spin all the time because it's more efficient with my way of using it. Also listening to music from that drive is absolutely destroying the drive making it spin up and down all the time causing immense wear and tear. Any ideas on how to stop it from spinning down? Please don't suggest bat files that keep creating editing a file.     Oh and here is the model of the drive: wdc wd10jpvx-22jc3t0 and my OS is Windows 10 64 bit.


In this code  kill = False   a = tr.Thread(target=func, args=(a, b, kill), daemon=True)   a.start()  And this is a tkinter app so how do I kill this thread like what command is threr to do that.

Is it possible to terminate a running thread without setting/checking any flags/semaphores/etc.?


In the story, relatives of a patriarch curry his favor in order to inherit his apartment.It might feature a son/grandson and his expecting wife. Possibly from the '70s. Not Billennium or Roommates, which do share similarities.

I remember a short story in which multiple generations of people being crammed into a small apartment in a city. The magical drink that either reduced or completely stopped aging was something like a soda that came in a six pack. The story focused on visual aspects of the drink at some point. The younger family members complained that their elders were living too long and apparently decided to water down the soda, I think that conclusion was ultimately left up to the reader. Many thanks for any help tracking down this story, might be one of Kurt Vonnegut's perhaps?


What follows is from Professor Barton Zwiebach of MIT:     The only problem with such a large field is an infinite self-energy   of the point particle limit. This problem is not really there in QED, as   any infinite self energy is renormalized away. There is actually an effective version of Maxwell’s equations, called nonlinear electrodynamics in which point charges have finite self energy, and electric fields cannot exceed a limit (just like the speed of objects is $< c$). This is also true in   classical string theory.  It is explained in Chapter 20 of my book on string theory."   What does it mean that the energy is renormalized?

I was reading Michio Kaku's Beyond Einstein. In it, I think, he explains that when physicsts treat a particle as a geometric point they end up with infinity when calculating the strength of the particle's field as you approach the particle.  First, did I get that part right?  Second, how does (in very simple terms) renormalization try to fix this in Quantum Mechanics? If you can include some type of word picture that would be great. Accepted answer will go to the clearest explanation.  Update  I got a little further in the book (lol) and Kaku talks about using symmetry to remove the divergences in the math. I'd appreciate an answer that incorporates this also. Thanks guys!


Is physicist Robert Oppenheimer's phrase “Now I am become Death, the destroyer of worlds.” grammatical in English? Why not "becoming" or "now I become"?

In the King James version of the Bible there is a verse like this:     The Lord is my strength, and my fortress, and my song. And He is become my salvation.   Is it still feasible to use "is become" instead of "has become" and what is the semantic difference?


I'm having problems aligning my objects to the pixel grid in Illustrator. As you can see in the picture, my object is correctly aligned with the pixel grid. However there are still parts outside of the green transform lines. Does anyone know how I can fix this? I've been trying align correctly with the direct select tool for over an hour with no luck.

Does anyone know if there's a way to have Illustrator CC (2014) constrain control points to the pixel grid? I understand that "Align to pixel grid" makes it so that a shape will try to match the pixel grid, but the actual control points don't line up to said grid... The image I've attached illustrates my problem.


There is a system composed of an ASP.NET web application, .NET windows services and shared .NET libraries. It has large number of classes, each containing multiple methods.  How to conveniently collect runtime data about execution of methods without having to modify each single class and method? The goal is to register execution of all the methods that are part of the system (except .NET Framework classes). The purpose of collecting this data is to learn what features of the system are never used by the users. We already performed static code analysis as well as eliminated pages that were never displayed based on IIS logs.

What profilers have you used when working with .net programs, and which would you particularly recommend?