I understand this is an unorthodox requirement and the background is too complicated to explain.   I have a big directory BIG_DIR that's being tracked by git. I have a SUB_DIR underneath the BIG_DIR, which is tracked as a part of the BIG_DIR.   Now I only want to keep the git tracking history related to SUB_DIR. I dont want to track BIG_DIR anymore, but I want to keep SUB_DIR as an independent repository, while keeping its history.   The whole BIG_DIR has no remote repo. It's all local. if that makes it easier.

I have a  repository which contains a number of subdirectories. Now I have found that one of the subdirectories is unrelated to the other and should be detached to a separate repository.  How can I do this while keeping the history of the files within the subdirectory?  I guess I could make a clone and remove the unwanted parts of each clone, but I suppose this would give me the complete tree when checking out an older revision etc. This might be acceptable, but I would prefer to be able to pretend that the two repositories doesn't have a shared history.  Just to make it clear, I have the following structure:  XYZ/     .git/     XY1/     ABC/     XY2/   But I would like this instead:  XYZ/     .git/     XY1/     XY2/ ABC/     .git/     ABC/


Has any specific policy about acceptability of links to Stack Overflow from third parties been adopted?  How does the StackOverflow community feel about this kind of thing?   I came across this question:    My first thought about that product licensing question up front was: Why would someone not ask a vendor licensing question... to the vendor?  Then I found the answer: The vendor's site directs users with technical issues (that won't fit in a tweet) to post on StackOverflow:   IMO, this particular site, while not really outlining the details of what kinds of questions will be accepted on Stack Overflow, does an adequate job of instructing users on how to post (e.g. "phrase it as a question"; give a "minimal example"; "tag your question".)

I recently saw a question about a problem (or possible bug) with some product on Stack Overflow. At first, I wanted to suggest that the asker post his question to that product's support forum.  When searching for the URL of that forum, I noticed that the product developer closed its support forums and now advises users to post all their questions on Stack Overflow instead.  Is this within the intended use cases of Stack Overflow, or is this abuse?


I still can't understand why the developers completely removed the function to let the Launcher dodge only maximized windows but is there a way to get this function back by tweaking dconf or so? this question is explicit to 13.10 where none of the patches or hacks work!

I don't like the auto hide launcher for it is too annoying for me. The launcher stays hidden and to reveal it, the mouse pointer has to be moved to the default hot spot. I'd instead like to have the hide to dodge windows previously available in Ubuntu 11.10. How do I change back to this behaviour?


For the last couple of months my system produces a strange problem with its display:    This will happen every time I close the lid or the system is left idle and suspends. The way I resolve the issue is a reboot and to just shut down whenever I'm planning on closing the lid.  Is there a way to fix this without the need to reinstall the OS? I don't have time to set everything up again at the moment but would obviously like the functionality back as this hasn't always happened.  Any help is much appreciated!

NB: Nvidia has released an official fix; please see ,  and/or .  Upon waking up Ubuntu 16.04 from Suspend, the following graphical glitches appear around all windows, context menus, and similar:      This is currently known to affect the following NVIDIA cards running the proprietary drivers:  NVIDIA GeForce 610M, driver version 375.39, 340.102 NVIDIA GT 630M, driver version 375.39 NVIDIA GTX 650, driver version 375.39 NVIDIA GT 740M, driver version 378.13 NVIDIA GTX 745, unknown driver version NVIDIA GTX 850M, driver version 375.39, 378.13 NVIDIA GT 940M, driver version 375.39 NVIDIA GTX 950M, unknown driver version NVIDIA GTX 960M, driver version 378.13 NVIDIA GTX 970, driver version 375.39 NVIDIA GTX 970M, driver version 375.39 NVIDIA GTX 980 TI, unknown driver version NVIDIA GTX 1060, driver version 375.26, 375.39, 378.09 NVIDIA GTX 1070, driver version 378.09  The above above list has been sourced from reports from other users here on AU,  thread, and  thread. NB: This is be no means an exclusive list. It probably effects nearly all Nvidia cards.  Furthermore, this issue has been replicated on a clean install where the only change was a software update and the installation of the latest NVIDIA drivers.  What is going on, and how can it be resolved?


What techniques are available for collapsing (or pooling) many categories to a few, for the purpose of using them as an input (predictor) in a statistical model?    Consider a variable like  (discipline chosen by an undergraduate student). It is unordered and categorical, but it can potentially have dozens of distinct levels. Let's say I want to use major as a predictor in a regression model.  Using these levels as-is for modeling leads to all sorts of issues because there are just so many. A lot of statistical precision would be thrown away to use them, and the results are hard to interpret. We're rarely interested in specific majors -- we're much more likely to be interested in broad categories (subgroups) of majors. But it isn't always clear how to divide up the levels into such higher-level categories, or even how many higher-level categories to use.  For typical data I would be happy to use factor analysis, matrix factorization, or a discrete latent modeling technique. But majors are mutually exclusive categories, so I'm hesitant to exploit their covariance for anything.  Furthermore I don't care about the major categories on their own. I care about producing higher-level categories that are coherent with respect to my regression outcome. In the binary outcome case, that suggests to me something like linear discriminant analysis (LDA) to generate higher-level categories that maximize discriminative performance. But LDA is a limited technique and that feels like dirty data dredging to me. Moreover any continuous solution will be hard to interpret.  Meanwhile something based on covariances, like multiple correspondence analysis (MCA), seems suspect to me in this case because of the inherent dependence among mutually exclusive dummy variables -- they're better suited for studying multiple categorical variables, rather than multiple categories of the same variable.  edit: to be clear, this is about collapsing categories (not selecting them), and the categories are predictors or independent variables. In hindsight, this problem seems like an appropriate time to "regularize 'em all and let God sort 'em out". Glad to see this question is interesting to so many people!


Can anyone please tell me how to define $x^\sqrt 2$ ? If it was $x^2$ or $x ^ \frac{1}{2}$, we could have said that  $x^2$ means $x \times x$ and $x ^ \frac{1}{2}$ means a number y such that $y^2 = x$. But  how to define $x^\sqrt 2$ ? Can anyone please help me ?

The way that I was taught it in 8th grade algebra, a number raised to a fractional exponent, i.e. $a^\frac x y$ is equivalent to the denominatorth root of the number raised to the numerator, i.e. $\sqrt[y]{a^x}$. So what happens when you raise a number to an irrational number? Obviously it is not so simple to break it down like above. Does an irrational exponent still have a well formed meaning?  The only example that comes to mind is Euler's identity, but that seems likes a pretty exceptional case. What about in general?


How to install gnome desktop in ubuntu 17.04?

This question exists as it fills a specific criterion.  While you are encouraged to help maintain its answers, please understand that "big list" questions are not generally allowed on Ask Ubuntu and will likely be closed per the . More information on the .   What kind of desktop environments or shells are there for Ubuntu users to install?  Please list a desktop environment or shell for each:   a description on why you like or suggest it (features, performance, etc.). a good screenshot, preferably of it running on Ubuntu and showing off some of its features. the minimal requirement for it to be usable, If there's any setting to lower it's requirement (Like kde's low-fat profile); how to enable the said setting some instructions on how to set it up if in the repositories, please provide a software centre link


My app uses HTTPS only.  I have SSL enabled from the properties window. Everything works well except, when I run the project, it runs on HTTP.  I then have to    change the URL manually to HTTPS, and then  change the port number to the SSL one.    How can I force the app to run as HTTPS?  Is there a quick fix for that (without using logic in my pages)?  I searched for this, but I haven't found a case that matches mine.  Note: I am using ASP.NET MVC4 with web API.

About 6 months ago I rolled out a site where every request needed to be over https.  The only way at the time I could find to ensure that every request to a page was over https was to check it in the page load event.  If the request was not over http I would response.redirect("")  Is there a better way -- ideally some setting in the web.config?


I have a generator, what is the most pythonic way to get its output placed in lists of N elements?  For instance, in the code:  >>> the_splitter(xrange(11).__iter__(), 3) [[0, 1, 2], [3, 4, 5], [6, 7, 8], [9, 10]]   i want the definition of the_splitter() function.

I have a list of arbitrary length, and I need to split it up into equal size chunks and operate on it. There are some obvious ways to do this, like keeping a counter and two lists, and when the second list fills up, add it to the first list and empty the second list for the next round of data, but this is potentially extremely expensive.  I was wondering if anyone had a good solution to this for lists of any length, e.g. using generators.  I was looking for something useful in itertools but I couldn't find anything obviously useful. Might've missed it, though.  Related question:


This isn't my material, I downloaded it and I'd like to add a PNG logo over the top.   I'm hoping to be able to have the faces with the texture still be metallic looking, just with a logo over the top.   Can this be done? I have duplicated the material so I can make changes as needed. Thanks in advance for any help!   I'm using Cycles render engine   Material:    Where I want my logo:

I'm designing this animal-type creature, and want to add a transparent .png image to its face with the face features (object has a subsurf). On the left is the image with the features, on the right is the part of the object where I want it to be.    I tried to import the image as a plane, but matching the shape of the plane with the face didn't work, and the lines of the face left shadows on the head, and could be seen as a different object from some angles (although it's the closest I've gotten yet). It looked like this:    So , I tried selecting the faces of the head that the features should go over, and create a new material for it. Unfortunately, since the .png is transparent, the result produced was this:    (where it's impossible to tell the transparency from a black background default color, and where I wouldn't know where to start to adjust size and position).  I also tried UV mapping, but then the whole object became black with the features repeated all over.   Is it something I have to go into Nodes for? I'm kind of stuck here. Creating a new material and applying it is simple, but applying a material that is an image is a bit more complex it seems... Ideally, I would reproduce the same technique for the adhesive bandage on its arm (seen on the right of image 1).


I know this question has been discussed many times but there does not seem to be a universal working answer.   I have a web page that displays data which is continually updated and I need to work out how I can prevent the web page from refreshing if there is no internet connection.   I have tried many different approaches but without exception, went I disable my internet connection, browsers displays   Firefox: Server not found   Chrome: There is no internet connection   IE: You’re not connected to the internet   I have looked into various browser plug-ins but none of them work.   I have taken a look at navigator.onLine but even using this browsers still display their own not connected pages. I have looked at using some sort of AJAX call without any success.   I do not need to worry about who is using which browser because this script is going to run on a known device configured to a known specification.   Is there a full proof method of preventing a page refresh until there is a connection?  loadDoc("example.com/comms_true.png", myFunction1); function loadDoc(url, cFunction) { var xhttp; xhttp=new XMLHttpRequest(); xhttp.onreadystatechange = function() { if (this.readyState == 4 && this.status == 200) { cFunction(this); setTimeout(function() { location.reload(); }, 30000); } else { } }; xhttp.open("GET", url, true); xhttp.send(); }  function myFunction1(xhttp) { setTimeout, 30000; }

How to detect the Internet connection is offline in JavaScript?


Say I’m looking for a list of which of my installed fonts support a given Unicode character. say the ⁂ and ☺ characters (an asterism and emoticon smile). What graphical program would I use to preview this characters in the given font?

How to find the appropriate font for rendering unicode codepoints ?  gnome-terminal find that characters like «🉃⼼😻🕲🝤» can be rendered with fonts like Symbola rather than my terminal font or the codepoint-in-square fallback (). How ?


This particular problem was asked in my assignment which could not be discussed due to pendamic.  Question : If f is holomorphic on $\Omega$/{a} prove that $e^{f(z)}$ cannot have a pole at a .  What I tried :If f has a pole of order k at a and let $|e^{f(z)}|\to \infty$ as z$\to$ a.   then I took $g(z)=\frac{f(z)} {(z-a)^k}$. Then $\frac{g(z)}{(z-a)^k} \to \infty $ as z$\to a$ .( But I don't know how to proceed in this case from here). Let f have an isolated singularity. I am confused in this part on which property should be used to prove that pole does not exists . If f has an essential singularity at a then also , I am confused on which result to use . Can it be proved that $e^{f(z)}$ will also have an isolated singularity at z$\to $ a ? If yes kindly give some hints . Any guidence will be really appreciated .

Let $f$ be analytic on $0<|z-a|<R$ for some $R>0$. If $z=a$ is not removable singularity of $f$, show that $e^{f(z)}$ has an essential singularity at $z=a$.  Since it's not removable singularity, it is either a pole of $f$ or essential singularity of $f$. The case of $z=a$ is a pole I can prove it. For the case of essential singularity, I write  $$ f(z)=\sum\limits_{k=0}^\infty c_k(z-a)^k+\sum\limits_{j=1}^{\infty}d_j\frac{1}{(z-a)^j}. $$ Call first series $g$ and second series $h$, then $e^{f(z)}=e^{g(z)}e^{h(z)}$. It is obvious that $e^{g(z)}$ is analytic at $z=a$ and $e^{g(a)}\neq 0$.Thus, it can't write as the form $(z-a)g_1(z)$ where $g_1$ is analytic at $z=a$.  Now, we focus on $e^{h(z)}$.  $$ e^{h(z)}=\sum\limits_{k=0}^\infty \frac{\sum\limits_{j=1}^\infty [d_j\frac{1}{(z-a)^{j}}]^k}{k!} $$ Then, in order to claim $z=a$ has essential singularity of $f$, I tried to write $e^{h(z)}$ as  $$ e^{h(z)}=\sum\limits_{s=0}^\infty e_s\frac{1}{(z-a)^s} (\star) $$  However, it seems that it shall be able to write as the form as $(\star)$, but do we need to worry about whether the series converges and whether we can change the double series? Or, is it possible to prove $z=a$ is essential singularity of $f$ avoiding to face this problem? Thanks.


I have bought a HP 819185-421 proliant microserver, and I want to install ubuntu server before buying hard disks. So, I burn Ubuntu 14.04 in a usb(4GB) using the software "ISO to USB", but after choosing the usb in the bios, it said "no OS found, please remove units without OS and reboot" (something like that, I do not remember the exacts words). I know that if I switch off the server, the usb does not save the configuration, but I only want to install the ubuntu server, make some test and after that, buy hard disk.  Thanks for all

I'd like to install Ubuntu server on my machine, is there a step-by-step instructions on how to accomplish that or a guide that will just go through the basic steps of installing Ubuntu Server from beginning to end.  Instructions originally for 13.04.


Do Libyan citizens who live in Libya and don't hold any other nationality need transit visas for the UK and Canada? The plan would be to travel on British Airways from Istanbul, Turkey to the Dominican Republic, with stops in the those two countries.

Is there a website or some other way to find out if I need a transit visa for a short stop in the UK on my way somewhere else? Ideally this should give me the answer for all nationalities, and take into account any other visas I may have.


I can separately query all the server or database level permissions, but I want to know other thing. What server role do the given permissions exactly belong to? For example I want to see all the permissions belonging to securityadmin server role, hence I'll be able to understand what privileges the role has. I want the same for database roles. Can I find this info in SQL Server system tables?  Thanks

I've searched around all over and haven't found a conclusive answer to this question.  I need a script that can give ALL permissions for an associated role.   Any thoughts, or is it even possible?  This gets me CLOSE - but I can't seem to flip it around and give the summary for roles, rather than users.     WITH    perms_cte as (         select USER_NAME(p.grantee_principal_id) AS principal_name,                 dp.principal_id,                 dp.type_desc AS principal_type_desc,                 p.class_desc,                 OBJECT_NAME(p.major_id) AS object_name,                 p.permission_name,                 p.state_desc AS permission_state_desc         from    sys.database_permissions p         inner   JOIN sys.database_principals dp         on     p.grantee_principal_id = dp.principal_id ) --role members SELECT rm.member_principal_name, rm.principal_type_desc, p.class_desc,      p.object_name, p.permission_name, p.permission_state_desc,rm.role_name FROM    perms_cte p right outer JOIN (     select role_principal_id, dp.type_desc as principal_type_desc,     member_principal_id,user_name(member_principal_id) as member_principal_name,    user_name(role_principal_id) as role_name--,*     from    sys.database_role_members rm     INNER   JOIN sys.database_principals dp     ON     rm.member_principal_id = dp.principal_id ) rm ON     rm.role_principal_id = p.principal_id order by 1


we know that an eigen operator give the eigen value and keep the wavefunction in corresponding position. but what is the simple physical meaning of this process because the wavefunction represent the matter waves.

Let's say we have a wavefunction $\psi$ and a measurement operator $\hat A$.  I understand how eigenvalues and eigenvectors of $\hat A$ describe the possible outcomes of the measurement.  I also understand that the average measurement can be computed as $\langle \psi|\hat A|\psi\rangle$.  It's still not clear to me what the direct meaning of $\hat A |\psi\rangle$ is. It is a wavefunction; how does its corresponding quantum state relate (in physical terms) to the original state $\psi$ and the measurement $\hat A$?


I am observing an increase in the predictive power of my logistic regression when I remove certain predictors. It might be a bug in my code, so I'm wondering: is this statistically possible? If so, what are the possible explanations?  Note: - there is strong multicollinearity in my predictors - I am not interested in interpreting my parameter values, I just want high predictive power - I have 15 regressors and a dataset size of 100k (10k for validation to avoid overfitting, 10k for testing) - I am using a multi-layer perceptron (neural network) - I measure predictive power by % of test cases correctly classified

Is it possible to overfit a logistic regression model? I saw a video saying  that if my area  under the ROC curve is higher than 95%, then its very likely to be over fitted, but is it possible to overfit a logistic regression model?


Since a point in mathematics is dimension less, how can we get an object of 1 dimension by combining dimension less objects ?  Further more, into how many parts can we divide a line  If we can divide a line segment and obtain an infinite number of points, doesn't this imply that the line segment should have an infinite length. This sounds really similar to Zeno's paradox but l want to understand how mathematicians treat the problem.  Finally if we can divide the line segment into an infinite numbers of points, is the set of points countable or uncountable ?  How does Cantor set fit into all this ?

I have extracted the below passage from the wikipedia webpage - Point (geometry):        In particular, the geometric points do not have any length, area, volume, or any other dimensional attribute.      I think the above passage imply\ies that the point is zero dimensional. If it is zero dimensional, how can it form a one dimensional line?     Physics texts sometimes talk of lines' being made up of points, planes' being made up of lines and so forth. Clearly a line segment, thought of as a connected interval of the real numbers, cannot be built as a countable union of points. What axiom systems define the building up of a line from points, or, how do we rigorously define the building of a line from points?       Links:   The section one () of part one of the book "Relativity: The Special and General Theory" seems to be giving Einsteins view on this matter.       Related: History of Euclidean and Non-Euclidean Geometry


Is there a firewall for Ubuntu 14.04.1 that asks for every program that wants to   enter or exit?

Does Ubuntu come with a preinstalled or automatic firewall? If not, do I need one?   I've read some articles about the advantages of Linux over other operating systems about security (no need to have antivirus, ...) but would like to be sure.


I have a PC with 5 hard drives (SSD and HDD). One of the drives has Windows 10. In the past, I have tried to install Ubuntu and Windows using the following method so there will be no interference between the two operating systems:  I Simply removed all the hard drives, except the one that I wanted to install Ubuntu, then install ubuntu and connect other hard drives. Then select the boot drive using the BIOS.  Can I do the same thing without taking out taking all the drives?  I mean I do not like  to see the GRUB on boot, I want windows to boot as default without the need for GRUB.

As noted by many people, Windows 8's UEFI requirements might will won't get in the way of installing Linux (or whatever), as the replacement bootloader will also need to be signed somehow. Some systems All systems will let you disable the signature requirement, but the feature might be hidden to disable or you might not be willing to give up on the benefits of a secure bootloader.  Is it necessary to replace the bootloader in the first place? To keep ourselves to software that's gone golden, how can I install Ubuntu 11.04 using Windows 7's own bootloader?


I have this following sql code:  $sql = "INSERT INTO data (Artist, Name) VALUES ('TF2', 'you're right behind me')";   The code itself looks normal but for some reason mysql doesn't want to allow me to save it. I get the following error:  "#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 're right behind me')' at line 1"   What I know the problem is because of the word "right" being reserved in mysql but I need to save it so how should my code look like. All help is appreciated

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 am trying to store my cities streets in a database. The names contain characters like ăîâșț(romanian characters) and öüóőúűéáí (hungarian characters). For example "Agrișelor" is stored as "AgriÃˆÂ™elor".  My code is a mess so I am not posting it, basically I am trying to encode end decode using the built in functions of PHP ('utf8_encode', 'utf8_decode').  I would like to get a function type solution for data input and output.  Edit: I forgot, the webpage displays the names recalled from the database correctly, I am getting this problem only in the stored data.

I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1.  Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur?  This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2.


So i'm making a game and so i'm just making all my 3d models for it and the boat that i making is for some reason see though in my game engine (unity 3D) and when like the inside of the model is see through but the outside seems to be good,so is their any way that can make the inside not see though i was hoping if anyone knew a way around this.

This is my mesh in Blender:    And this my mesh when placed in UDK:    As you can see it doesn't have the human head/chest part, parts of the hood are invisible, and it has some white lines. Why?


I just noticed something in a rather innocuous text that I was sending a friend. The word "Left", for instance, could mean, "Hey, have you left already?" or "Is anyone left here?". Both these meanings are completely different from each other even if they are using the same word(in this case, "left").  My question is, "Does anyone know more of such words? And if so, is there a specific term for them?"

I am looking for a list of all English words that are their own antonyms. Off the top of my head, I can only think of "either", "fast", "to dust" and "to lease", but there must be dozens more. Can you provide a link to a comprehensive list, if such exists?  Also, what are such words most commonly called? I like the term "Janus word" I once heard, but is that widely understood?  Edited by popular demand to make it absolutely clear that this is not a community wiki poll.


In the Ubuntu 14.04, when I reboot my machine, the language icon keyboard disappeared.  How can I solve this problem?

Icons sometimes disappear from the Panel notification area when Ubuntu 14.04 starts up. Not the same icon disappears every time, and only one icon disappears at a time. This happens infrequently, and I have also seen it happen on older versions of Ubuntu. The next time I start up Ubuntu, all of the Panel icons are back in the notification area of the Panel where they should be.  Here are some examples of icons that have disappeared from the Panel notification area at startup.   battery indicator   network indicator   Thunderbidownload managerrd Mail sound clock icon (gear in Unity / ⏻ in GNOME) for accessing functions such as Lock/Log Out/Suspend/Restart/Shut Down, etc. from a dropdown menu   All of these icons have disappeared from the Panel at least once, however the indicator icon for Psensor temperature monitor application which usually takes about one minute after startup to appear on the Panel notification area has never disappeared from the Panel at startup.  How can I make a missing Panel icon reappear without rebooting the operating system? I would prefer a general solution that works for any of the missing icons in the list.


I've been trying to find a solution to the problem I'm having, which is that I spawn in the middle of nowhere and die right away in Agrarian skies. I can't find any sollution for multiplayer, only for singleplayer.   Is there anything I can change in my server to spawn on the actual island? Ive tried switching to creative mode and writing /jspawn, but that does nothing. I've also tried downloading the map and putting it in the saves folder, but that prob only works for singleplayer.   Anyone that has done this and knows what I need to do? please

I just started on Agrarian Skies, and when I spawn in a normal world, there is no land to stand on. I immediately lose my 2 lives and have to start over. Is this intended behavior?


What is a loss function? How can we relate the slope of Linear Regression with  Sum of Squared Errors?

My notes define a loss function as the 'cost' incurred when the true value of $\theta$ is estimated by $\hat\theta$. What kind of cost is it talking about? monetary cost? or is it something related to errors?


While reading Herbert Schildt I came across partial implementation where overriding is'nt mandatory , But I fail to understand why do we implement such an interface where we don't override its methods :  interface CallBack{   void callback(); }  abstract class Incomplete implements Callback {     //Legal void someMethod(); }   Is there any practical use of such a class or it's just theoretical ?

A curious thing happens in Java when you use an abstract class to implement an interface: some of the interface's methods can be completely missing (i.e. neither an abstract declaration or an actual implementation is present), but the compiler does not complain.  For example, given the interface:  public interface IAnything {   void m1();   void m2();   void m3(); }   the following abstract class gets merrily compiled without a warning or an error:  public abstract class AbstractThing implements IAnything {   public void m1() {}   public void m3() {} }   Can you explain why?


I am a Full-Time research scholar in finance about to submit my thesis in a month or two.  After this is it good to go for post-doc or as a lecturer in finance?  If I apply for lecturer will colleges entertain it as I am a fresher?  And one more doubt I got is, Am I eligible to apply for Post-doc position after submitting my thesis? or should I wait until the completion of Vivo-voce and/or graduation? Because its time-consuming process to receive Vivo-voce.  Kindly give your valuable suggestions

My earliest PhD graduation date is 10 months away. Funding permits me to stay 1–3 months longer, so the final date is still uncertain.  It is never too early to make contacts for possible post-docs. But how long in advance is too early to formally apply to post-doc job openings or funding opportunities? Depending on the bureaucracy, the path from applying to starting can probably be anything from a week up to a year — someone I know is applying with  which had the opening advertised in August, application deadline in October, will have interviews in December/January, and the commencement of work only in September, 13 months after the initial job advertisement. My personal guess is that the long time between interviews and starting is to create a level playing field between those who do and those who don't need to go through a visa application procedure.  If I'm too early in applying for a post-doc, a hosting institution might prefer someone who can start earlier and where the graduation date is more certain. For example, in my case the graduation date is still uncertain, so there is a risk in accepting even if they are willing to wait. Project funding might also require the money to be spent rather soon.  If I wait too long, there might be a considerable period where I'm between jobs. Having a long (>6 months) period between jobs is a disadvantage for me. Maybe it's also a disadvantage for a hosting institution (I'm not sure).  How do I find the balance? For example, considering the duration of funding and visa applications, does it make sense to apply e.g. ? Or is it in any case virtually inevitable to have at least several months before my PhD graduation and the start of a post-doc?


I am working on a seemingly bizarre problem and cannot make any progress at all.  I am wondering if anybody has come across a similar problem, and if so just how to start it.  The problem is as follows.  Find a sequence of polynomials $p_i$ on $\mathbb{C}$ such that all of the below are true:  1) On the right open half-plane we have $p_i$ converges to $1$  2) On $i\mathbb{R}$ we have $p_i$ converges to $0$  3) On the left open half-plane we have $p_i$ converges to $-1$  So my idea is that with an appropriate application of Runge's Theorem and the reflection principle we can pretty much just concern ourselves with satisfying the first condition using not polynomials, but some sequence of analytic functions $f_i$.  And then hopefully the sequence of $f_i$ will work out for the rest haha  But basically I have no idea how to start this problem.  Does anyone have any ideas?  Thanks a lot in advance!

Is there a sequence of polynomials $P_n$ such that   $\displaystyle\lim_{n \to \infty} P_n(z) = \begin{cases} 1, & \text{Im } z > 0\\ 0, & z \text{ is real,} \\ -1, & \text{Im } z < 0 \end{cases}$  I have no clue where to start from. Please provide some hints. Thanks in advance.


Is it even OK to ask such questions? If it is, should I ask these on  or somewhere else?  For example I need a suggestion about good sound speakers that have quite long cables (for some specific reasons)?

Stuff like polls, recommendations based on subjective constraints, puzzles, webcomics etc. do not belong on the serious main SE sites, where professionals should be considered at work and having just a few spare minutes ("code's compiling") to answer questions, so they should not be distracted by such things. However, I'd also like to have a home for these things still using the SE engine. For the reason I mentioned before, this needs to be a separate place though. Let's call it four.[sitename-here].com.


Someone has sent me a link to a publicly viewable plaintext file in Google Drive. I can see it in the viewer by appending /view to the url, and in a 'preview' mode by appending /preview. But how do I just get the raw text file (it's data file and I want to read it straight into R)? I'me loathe to heck it by extracting the text string out an html tag: there must be a simpler way.  Edit - it has been suggested that I try , but that doesn't work for files which cannot be converted to google docs. In my case the file is a large (2Mb) text file with ID 17iI2COb-KZfc0uJ6ocrtjxeCvevR51_m. The link  works, but the link  does not.

When you share a Zip file in Google Drive, you land on a page to view all the files inside the zip file and to download the entire file the user has to click File → Download. I've noticed a lot of users don't get this so I actually have to tell them to click File → Download when all I really want to do is give them a link to directly download the file.


How to use the command \leqslant with pgfplots ?  \documentclass{standalone} \usepackage{pgfplots} \definecolor{mycolor}{cmyk}{0.00,0.18,0.29,0.02} \begin{document}  \pgfmathdeclarefunction{dnorm}{2}{% \pgfmathparse{1/(#2*sqrt(2*pi))*exp(-((x-#1)^2)/(2*#2^2))}% } \begin{tikzpicture} \begin{axis}  [domain=0:10,  samples=500,  height=5cm,  width=10cm,  axis lines*=left,  enlargelimits=false, clip=false, axis on top,  every axis y label/.style={at=(current axis.above origin),anchor=south},  every axis x label/.style={at=(current axis.right of origin),anchor=west},  xtick=\empty,  ytick=\empty,  xlabel=$x$, ylabel=$y$,  style=thick,  ]   \addplot [fill=mycolor, draw, domain=3:4.75] {dnorm(4,1)} \closedcycle;                \addplot [thick, smooth] {dnorm(4,1)};  \node (a) at (axis cs:3,-0.03) {$a$}; \node (b) at (axis cs:4.75,-0.03) {$b$};  \node (title) at (axis cs:4,0.45) {$P(a\leq X \leq b )$};  \end{axis}  \end{tikzpicture}  \end{document}

I have the following line: $0 \leqslant b \leqslant 1$  I want to display 0 <= b <= 1, but I get Undefined control sequence  thanks


I'm using ssh to connect to a remote Linux machine like this:  ssh -i .ssh/path/to/id_rsa -p 22 user@host 'cd /path/to/dir'   I'd like some commands to be executed upfront (such as cd /path/to/dir) and then proceed with my own business, but I get logged out right away after the commands are run. Any way to stay logged in?

I SSH into a multitude of different servers every day and some of them have different filesystem structures for their websites. Each time I change server, I have to work out where I'm going to get to the files I really want (because it's very rarely that I want to be in ~). I use Fabric files to automate all my actions (pushing to git, automated SSH to the server to pull from git, restarting the web application, changing dependencies, etc), so I was wondering if I couldn't also tell it that I want to SSH into the right directory so I can run fab ssh and be in a normal SSH session, just in the right place and start working immediately. This is not about Fabric though; please ignore it. Fabric is just running a batch of commands. My argument is with the ssh command. That's what I'll be telling Fabric to run. So how I can get ssh to cd into a specific directory on login? Note: this cannot be a server or user-wide thing. I have multiple websites under one user on some servers so sticking something in ~/.bashrc would not work for me.


I know following expression   $$n = {n\choose 1 } $$   $$n^2 = {n\choose 2 } + {n+1\choose 2 }$$  but how about $n^3 = $?    Are there simple expression?

Is there a general expression for the pth power of a natural number k in terms of binomial coefficients?   I found this identity in a high-school text, which was obtained by simply equating coefficients:  $k^3 = 6 \binom{k}{3} + 6 \binom{k}{2} + \binom{k}{1}$  I would like to know the general expression for $k^p$ in terms of binomial coefficients.   I would also appreciate it if someone could tell me the names of texts which might cover such expressions, and what they can be used for.


I'd like to form this question:     Is she beautiful or smart or {neither one/ neither one of them/none of them}?    So do I need 'of them' for sure or can I omit 'of them' and say 'neither one' or only 'neither'? I'd like to keep it simplest possible.  Which one is correct?   Is she beautiful or smart or neither one? Is she beautiful or smart or neither one of them? Is she beautiful or smart or none of them? Is she beautiful or smart or neither? Is she beautiful or smart or none?   The duplicate question does not answer my question. My question is not about single plural verb harmony. It is about whether I can omit and if so to what extent I can omit to give the same meaning in simplest way and that according to what one prefers neither over none or vice versa.

In a comment on English Language & Usage I read the following answer responding to a(n) asker's question: "Neither sound natural." I have always had more than one doubt on the "neither" usage and I would like understand(ing) the "secrets" to use this word better or, at the best, correctly. So, let us consider the following examples:  1 Neither sound natural. 2 None sound natural. 3 No one sound natural. 4 Neither of them sound natural. 5 None of them sound natural. 6 No one of them sound natural. 7 Neither sounds natural. 8 None sounds natural. 9 No one sounds natural. 10 Neither of them sounds natural. 11 None of them sounds natural. 12 No one of them sounds natural.  Comparing the above sentences (one) with each other, can anybody explain which is grammatical and why?


I have multiple visa schengen from Netherlands as per my trip plan was to travel Amsterdam but then due to some changes i have to drop my travel to netherlands. Now if i need to travel to spain on same visa issued by netherlands state, can i travel or apply for spain schengen ? Thanks

I planned to travel on my German-issued Schengen visa to Berlin for 7 days by myself and my tourist multiple entry visa got approved. However, now it looks like I will not be able to go to Germany during those dates due to work commitments.   Can I do the following instead:   Can I travel to Germany at another time during the validity of my visa for 7 days? Can I travel during my initial intended period of travel to some other Schengen country? If so, my port of entry will change to another country. However, given my travel to Germany later on, Germany will still be the country I spend my most time in overall.  Do I need to let the German embassy know of my change in travel plans?   From comment:     So original plan: 7 days Berlin and that's it. New plan: 4 days probably Greece or Hungary during the same week as the original plan as I have to work some of the days now and the flight tickets are too expensive for the days I want to go. Following this trip, another trip to Frankfurt for 9 days in October. All for tourism purposes, and change only due to work commitments and flight prices going up.


Recently I applied for a Schengen visa in Netherlands for business purpose but the visa was refused, due to the reason below:     One or more member state(s) consider you to be a threat to public policy, internal security or public health as defined in Article 2 (19) of Regulation (EC) No 562/2006 (Schengen Borders Code) or the international relations of one or more of the Member States). One or more EU Member States have lodged an objection to your entry into the Schengen Area. To issue a Schengen visa in the face of this objection would be damaging to international relations.   I have a good travel history including China, Singapore and UAE and also I traveled to Italy twice (2014 and May 2017). I got another visa in July 2017 but due to some reason I wasn’t able to travel and I never got any refusal or any problem getting a visa.  During my travel I never overstayed or done anything that may affect my travel history.  Can anyone tell what could have gone wrong which resulted in my refusal?

I applied for German Schengen visa as a medical escort to my relative in a different country from  where I reside, but my visa application was refused and the refusal letter  was written in German as the following:        Ein oder mehrere Mitgliedstaaten sind der Auffassung, dass Sie eine Gefahr für die öffentliche Ordnung, die innere Sicherheit, die   öffentliche Gesundheit gemäß Artikel 2 Absatz 19 der Verordnung (EG)   Nr 562/2006 (Schengener Grenzkodex) oder die internationalen   Beziehungen eines oder mehrerer Mitgliedstaaten darstellen.      I was in Germany for nearly a year with my relative during his treatment; I extended my stay there 3 times; and I returned back home two months ago in order to renew my passport. I applied again using the same documents that I used for my extension in Germany.    First, can anyone tell me what the refusal means? Next, is there any possibility that there is a mistake in the assessment?    Note: In English this reason is...     One or more member state(s) consider you to be a threat to public   policy, internal security, public health as defined in Article 2(19)   of Regulation (EC) No 562/2006 (Schengen Borders Code) or the   international relations of one or more of the member states).


I have tried to remove all folders from my current directory using Linux command rm -rf *. But the following error occurs and the respected folder is also not deleted.  rm: cannot remove ‘Xenon_R3_S/Datapath_r/ver/.nfs000000000409508f0003f7b0’: Device or resource busy

I removed a file and now I see:  $ ls total 64 -rw-rw-r-- 1 502 17229 Sep 17 16:42 page_object_methods.rb drwxrwxr-x 7 502   238 Sep 18 18:41 ../ -rw-rw-r-- 1 502 18437 Sep 18 18:41 new_page_object_methods.rb -rw-r--r-- 1 502 16384 Sep 18 18:42 .nfs0000000000b869e300000001 drwxrwxr-x 5 502   170 Sep 21 13:48 ./ 13:48:11 *vagrant* ubuntu-14 selenium_rspec_conversion   and if I try to remove it:  $ rm .nfs0000000000b869e300000001 rm: cannot remove ‘.nfs0000000000b869e300000001’: Device or resource busy   What does this indicate?  What should I do


I have a 30-m elevation raster as well as a set of points that overlay the raster.    For each point, I want to calculate the average elevation within a 5-km radius of the point.  One way I was thinking of doing this was by creating 5-km buffers around each point, then using those buffers to calculate the average values of the elevation raster.  This should work but I find it hard to believe that there is no easier way of doing this.  Does anybody know?    I would prefer a solution using ArcGIS 10.1 for Desktop but I could use R too.

I have a Buildings (polygon) shp file and a DSM. what I wanted to do was to get the pixel values for all the vertices of those buildings, and find another pixel value just around those vertices (say 2m, but exclude values coinciding with the building) that will give the maximum difference when subtracted to the value of the vertex. Finally, retain only the vertex that gave the maximum difference for each building.  What I did is I used the 'Feature to Point Vertices' in ArcMap to convert my building vertices into a point shp file. Then I made a 2m buffer around these points and I used the Erase tool using the Buildings as the erase feature. I thought I'd get the value for the vertices using 'Extract Values to Point' tool and then use Zonal Stat as Table to get the minimum values on the buffer circles. This is where my problem starts, ArcMap won't perform the Zonal Stat as Table because I have overlapping circles and performing the process on each circle is time consuming.  Does anyone have a suggestion to do it in a more efficient manner?


I am trying to find Wien's law from Planck's equation but instead of $\lambda$ I am finding frequency.   I found it:  $$\nu_{max} = \frac{(2.82)k_bT}{h}.$$  The following question asks: Why $\nu_{max}\neq {c}/\lambda_{max}$?  I cannot use $\nu = \frac{c}{\lambda}$ to turn Wien's law into frequency: $$\lambda_{max}=\frac{b}{T},$$ where $b$ is Wien's displacement constant.   EDIT   The question I am wondering about is b)

I am drawing a blank when it comes to equation transformation. Wikipedia  for the spectral radiance of black body:   First as a function of frequency $\nu$: $$I(\nu, T) = \frac{2 h \nu^3}{c^2}\cdot\frac{1}{e^\frac{h \nu}{k T} - 1}$$ Then as a function of wavelength $\lambda$ : $$I'(\lambda, T) = \frac{2hc^2}{\lambda^5}\cdot\frac{1}{e^\frac{h c}{\lambda k T}-1}$$   And I don't see how they get $\lambda^5$ term. I'm assuming that the transformation is just $\nu \rightarrow c/\lambda$, but that gives $$ \frac{2 h \nu^3}{c^2} \Rightarrow \frac{2 hc}{\lambda^3} \neq \frac{2hc^2}{\lambda^5} $$  Similar transformation happens at other parts in the article also. I'm obviously missing something, likely completely trivial.


I was looking at the  and trying this code:  from fractions import Fraction  >>> print("Fraction (0.5):", Fraction(0.5)) Fraction (0.5): 1/2 >>> print("Fraction (0.1):", Fraction(0.1))  Fraction (0.1): 3602879701896397/36028797018963968 >>> print(1/10)  0.1   Looking at the Fraction(0.1) result I thought it was my computer problem, but when I tried it on several computers the results were same.    My question    is there any computational reason to choose these odd numbers 3602879701896397/36028797018963968 instead of 1/10 just like 1/2 as it chosen for Fraction(0.5). more of these exist in python?

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


Question: Let $P(p, q)$ be a first quadrant point on $x^2/a^2 −y^2/b^2 = 1$. Let $D$ be the point where the tangent at $P$ meets the line $x =a^2c$. $F_2$ is the focus $(c, 0)$. Show that $∠DF_2P$ is a right angle. I believe the way to solve this problem is to confirm that the slope of $DP$ is the negative reciprocal of the slope of $DF_2$.But the points being $(p,q)$, $(a^2,y)$. and $(c,0)$ doesn't seem to get me there.

Is there a general proof for this?  The portion of the tangent to any conic intercepted between the point of contact and the directrix subtends a right angle at the focus of the conic?  For parabola, it can be solved this way: the tangent at $P=(at^2, 2at)$ is $ty = x + at^2$. This meets the directrix at the point $Q=(-a,a(t^2 - 1)/t)$. Now, $\text{Slope of }SQ\times\text{Slope of }SP = -1$. Hence, $∠PSQ = 90°$. A similar way of writing the parametric coordinates and equating the product of slopes to $-1$ yields the desired result for other conics. But is there a geometric proof for any general conic?


I downloaded the Universal USB Installer 1.9.5.2 from   But when I am running it, the Create icon is not working and I am unable to figure out what the problem is? I even formatted the pendrive (8GB) but the result was same.

This is the third time I've tried to install Ubuntu Server 14.04.03 64-bit on the same laptop, and each time it caused different problems.  Each time I wrote the same iso image to a USB flash drive by using a different application and OS.   Universal USB Installer (pendrivelinux.com) from Windows WinImage writer from Windows built-in image writer from Linux Mint 17.2    The iso image is the same in all three cases, the USB flash drive is the same, and the laptop is the same. However each time the installation of Ubuntu gave me different installation options. For example, the last time I installed Ubuntu, it didn't show all the packages to choose while installing (Basic Ubuntu server, etc.).


I want to upgrade to the newest version of Ubuntu, but I keep getting the error "Not enough free disk space". The upgrade needs a total of 90.6M of free space.  My problem is that boot presently uses 51.6 MB of space and only has 5 MB left. I.e, the total size of boot is only 56.6 MB. The upgrade requires 90.6MB.  I have tried using gparted to resize the partition that boot is on, but I have a problem.  There's plenty of free room left on my hard drive at 435 GB free, 25 GB used.  I have 2 partitions. 1 is 255 MB, the other is 496 GB.  This is the warning message that appears in gparted   When I click on resize/move for the main partition, the slider bar won't move.   I've also done the automated clean up, but it doesn't remove enough of the files to leave 90.6 MB free.  How can I expand the boot partition?

Previously, I have installed Windows 7 on my 320 GB laptop with three partitions 173, 84 and 63 GB each. The 63 GB partition was where the Windows was installed. The rest were for file containers.  Now I changed my OS to Ubuntu 12.04 LTS. I installed Ubuntu by replacing the entire Windows 7 on the 63 GB partition. The rest of the partitions remain as an NTFS Windows partition and I can still access them both (the 173 and 84 GB partitions).  Now I want to change the two partitions of Windows into an Ubuntu format partitions plus most importantly, I want to extend the 63 GB partition to more than a 100 GB because at the moment I am running out of disk space. Whenever I try to install any application, especially using wine, it always complains for a shortage of disk space.  How do I do the extending activity before I entirely format my laptop again and lose all the important files on my partitions?


I am working through some basic java tutorials online, and I have been stuck for the past few hours on a Null Pointer Exception in a Bank Account program. Usually when I encounter these, I can pretty quickly resolve the bug, but in this case the error always points to the line of the button where I call a method (deposit or withdraw). I'm not sure what precisely the issue is, since I have initialized all the variables I am using in both classes, but I am still encountering this exception. Any ideas what is going wrong?  BankAccount.java  import javax.swing.*;  class BankAccount { private int accountBalance; private JTextField stateTextField, balanceTextField;  public BankAccount(JTextField stateField, JTextField balanceField) {     stateTextField = stateField;     balanceTextField = balanceField;     accountBalance = 0; }  public int getBalance() {     return accountBalance; }  public void setBalance(int balance) {     accountBalance = balance; }  public void withdraw(int amount) {     accountBalance = accountBalance - amount;     displayState(stateTextField);     displayBalance(balanceTextField); }  public void deposit(int amount) {     accountBalance = accountBalance + amount;     displayState(stateTextField);     displayBalance(balanceTextField); } public void displayState(JTextField field) {     if (accountBalance>=0) {         field.setText("Ok");     } else {         field.setText("Overdrawn");     } }  public void displayBalance(JTextField field) {     int balance = accountBalance;     field.setText(Integer.toString(balance)); } }   And the interface where I use BankAccount.java:  BankAccountInterface.java  import java.awt.*; import java.awt.event.*; import javax.swing.*;  public class BankAccountInterface extends JFrame implements ActionListener { private JLabel balanceLabel, stateLabel, withdrawLabel, depositLabel; private JTextField balanceField, stateField, withdrawField, depositField; private JButton depositButton, withdrawButton, clearButton; private BankAccount account;  public static void main(String[] args) {     BankAccountInterface demo = new BankAccountInterface();     demo.setSize(750, 400);     demo.setLocationRelativeTo(null);     demo.createGUI();     demo.setVisible(true); }  public void createGUI() {     setDefaultCloseOperation(EXIT_ON_CLOSE);     Container window = getContentPane();     window.setLayout(new FlowLayout() );      stateLabel = new JLabel("State:");     window.add(stateLabel);      stateField = new JTextField(10);     stateField.setEditable(true);     window.add(stateField);      balanceLabel = new JLabel("Balance:");     window.add(balanceLabel);      balanceField = new JTextField(10);     balanceField.setEditable(true);     window.add(balanceField);      depositLabel = new JLabel("Deposit:");     window.add(depositLabel);      depositField = new JTextField(10);     depositField.setEditable(true);     window.add(depositField);      withdrawLabel = new JLabel("Withdraw:");     window.add(withdrawLabel);      withdrawField= new JTextField(10);     withdrawField.setEditable(true);     window.add(withdrawField);      depositButton = new JButton("Deposit");     window.add(depositButton);     depositButton.addActionListener(this);      withdrawButton = new JButton("Withdraw");     window.add(withdrawButton);     withdrawButton.addActionListener(this);      clearButton = new JButton("Clear");     window.add(clearButton);     clearButton.addActionListener(this);      BankAccount account = new BankAccount(stateField, balanceField); }  public void actionPerformed(ActionEvent e) {     if (e.getSource() == depositButton) {         int depositVal = Integer.parseInt(depositField.getText() );         account.deposit(depositVal);     } else if (e.getSource() == withdrawButton) {         int withdrawVal = Integer.parseInt(withdrawField.getText() );         account.withdraw(withdrawVal);     } else {         depositField.setText("");         withdrawField.setText("");         stateField.setText("");         balanceField.setText("");     } }  }

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?


My program is :  def question_fourth_solution(array_nums):     odd_len = len(list(filter(lambda x: (x%2 != 0),array_nums)))     even_len = len(list(filter(lambda x: (x%2 == 0),array_nums)))     print(odd_len,even_len)     return array_nums  question_fourth_solution([1, 2, 3, 5, 7, 8, 9, 10])   I want my output in tuple form like given below: (5,3)

I have a function where I need to do something to a string.  I need the function to return a boolean indicating whether or not the operation succeeded, and I also need to return the modified string.    In C#, I would use an out parameter for the string, but there is no equivalent in Python.  I'm still very new to Python and the only thing I can think of is to return a tuple with the boolean and modified string.  Related question:


I'm hoping to apply for the UK visa, but have been holding back because I'm worried I'll get refused (I'm Sri Lankan, refusal rate is high for us!).  I'm a student doing my Master's course in Russia. Almost each summer when I was doing my bachelor's degree (also in Russia) I traveled to many East-Asian countries like China, Japan, Singapore and Thailand.  This year I'd like to visit the UK (in winter because I got an internship during summer).  Since I'm a student, I only have about £450 in my own bank account. My mother will be sponsoring me. She has a fixed account with £5,000 and is hoping to spend £1800 out of it for my trip.   She'll be left with £3200. Her pension plus my father's salary is £300 per month and my father's fixed account deposit is £5000.  (My married sister who earns a £1000 per month takes care of utility bills in the house, because her husband earns more than enough).  I want to know whether they'll think this amount is okay for my mom to get by on after paying for my trip? I get free tickets each year through my sister (she works at an airline).  If they do, then will they accept fixed deposits?

I am an Indian citizen studying in Italy on an Italian visa that expires 19 November, 2015. I have permesso di soggiorno. I want to visit the United Kingdom for my vacations for a week during March. I know the procedures already, however I am a little bit confused about the amount that I must show as a proof of support with my bank statements. I will stay for a week with my friends who are also students in Italy and will be in London for 5 days. What would be the amount in Euros that I need to show for my visit to UK?


I usually use numpy for my processing but I'm trying to make the most of the power of GeoPandas for my spatial data. I have some point data (shapefile) and a vector grid (fishnet) as a separate shapefile. I would like to get the points that fall within each vector grid and then do some basic statistics on them (e.g., average). Each point has an X co-ord, y co-ord and a Z value. I would like the mean value of each that falls within a grid cell. All answers I have seen so far are either testing if one point is within a polygon, or does not go further and calculate statistics, only returning a boolean array. From  I got this piece of code: point = geopandas.GeoDataFrame.from_file(pointfile.shp) poly  = geopandas.GeoDataFrame.from_file(gridfile.shp)  pointInPolys = sjoin(point, poly, how='left') grouped = pointInPolys.groupby('index_right')  but as I'm pretty new to Pandas I'm not sure how to get at the data in this group (or really what a group is) so I can calculate the mean value of the points. How do I get the data and perform basic statistics on it?

I am trying to estimate summary statistics of points located inside a polygon. Each points in the point layer is associated with N attributes. My target is to summarize (say mean, min,..) the attributes of points located within a polygon and populate the attribute fields of the corresponding polygon.   I am looking for a solution using GeoPandas or other Python libraries.   import geopandas as gpd    gdf_points = gpd.read_file('/path_to_points.json') gdf_polygon = gpd.read_file('/path_to_polygons.json')  dfsjoin = gpd.sjoin(gdf_polygon ,gdf_points)   Now, how can I summarize the stats for each attribute in the point layer and add it to the polygon shapefile? Which function can I use?  I am looking for something that is functionally equivalent to ESRI ArcGIS  with


What is the best lens for kitesurfing photography?  A similar question was asked before, but I need a bit more clarity if possible.  I'm hesitating between the Canon 500mm f4 II vs Canon 400mm f2.8 or Canon 200-400 with 1.4x  I have a 5D Mark iv (and a 6D body as well).  I have the 70-200 f2.8, which is a great lens that I use for indoor sports, but I feel the need for longer reach to photograph kitesurfing from the beach. I also used the 70-300 that has a bit more reach but IQ seems far below the 70-200. Finally, in terms of my current gear I just ordered the Canon 100-400L II and also a 1.4x teleconverter to get some of that reach and flexibility   My doubts are for kitesurfing. I believe I need the reach, the aperture is important but I tend to shoot with good light. I wonder about the need for the flexibility of the zoom (hence my adding into the mix the 200-400 1.4x TC)  The 500mm f4 II has the focal length, IQ, not too heavy (compared with the 600mm, the 400mm 2.8 or the 200-400) and reasonably fast. It does not have the widest aperture of 2.8, nor the zoom flexibility  The 400mm f2.8 seems to be the lens for sports. However for indoor sports I use the 70-200 f2.8, but for outdoors and in particular for kitesurfing with reasonable light I wonder if that aperture is really a must  The 200-400 f4 1.4x seems great for the flexibility in focal length at a decent IQ. Having ordered the 100-400 II may provide me that flexibility (although losing IQ)   What's the experience of kitesurfing photographers, do you need the zoom flexibility? Do you value the focal length more? What would you recommend?  The other possibility for reach is getting a new body 7D mark ii (although it may be an overkill for camera bodies) to take advantage of the cropped sensor, but I fear I may lose out on IQ vs the FF that I could crop in post if need be.  Thanks!

I'm just trying to decide which new lens to get. I need to take surf and windsurf photos from onshore. Sometimes 300 mm is enough but there are many times they are too far away. I have a sigma 70-300 but I need something better, if the light is not perfect it doesn't give me the sharpness I hope for. I can not afford the 400L 2.8 of course, so I'm trying to choose between the Canon EF 100-400L, Canon EF 70-300L (which I heard is far better than the base one), or Sigma 50-500. My body is a canon 600D.


I need to extract text from a bufferImage using tessearct library (tess4j), however function throws a NullPointerException. PS: when I execute the function getImageText() out side the flatMap scope, the function worked perfectly public String getImgText(BufferedImage bufferImage) throws TesseractException {         ITesseract instance = new Tesseract();         try         {             if (instance == null){                 System.out.println("instance is null");             }             String imgText = instance.doOCR(bufferImage);             return imgText;         }         catch (TesseractException e)         {             return "Error while reading image: "+e.getMessage();         }     }  e_stream.flatMap(new FlatMapFunction<BufferedImage, String>() {                 @Override                 public void flatMap(BufferedImage iBuffer, Collector<String> out) throws Exception{                     TextExtraction ocr = new TextExtraction();                     String cv = ocr.getImgText(iBuffer);                     out.collect(cv);                 }             }).print();


Can 'believe' have a different meaning/connotation than 'think'?   I think you would use 'believe' if you want to stress that the thing that you believe will happen means very much to you and you are convinced it will definitely happen. Think, however, is less emotional and you don't stress whether you are convinced or not sure if something will happen - it is neutral.   For example:     I think he will win.          -> neutral position, based on what someone sees     I believe he will win.   -> Convinced he will win, emotional  Would you say that is the case?

These are the three most common ways to say "I think." (At least, I believe so. I mean, I think so. Um...)  Are there any subtle differences between them? Are there situations where one of the three is more suitable than the others? Can you say you hear a particular form all the time in the streets, while the other two are much less common?


Considering motion to be relative, consider these two cases as follows   An observer is standing on the sun and observing the earth and the earth has no background (no stars and stuff in the background). The observer notices the earth to be rotating and the sun to be stationary. So the observer on sun might make the statement: "Earth doesn't revolve but rotates and the sun is stationary"     Another observer is standing on the earth and might notice that the earth is not rotating but is revolving around the sun. So the observer on earth might make the statement: "Earth revolves and the sun is stationary".   So, can we say the different statements made by the two observers are both true from their own frame of reference?

Earth rotates on its axis and revolves around the sun, , the galaxy is also moving. So Earth's net rotation as observed from a fixed inertial frame consists of all these contributions (and is rather complex). Now a  on earth is supposed to tell the experimenter whether the earth is rotating or not. See a recent question on this forum  Basically for a Foucault's pendulum, the plane of the oscillation of the bob rotates, as the Earth rotates. But, the Foucault's pendulum does not single out one type of rotation, it gets affected by all. Therefore the rotation of plane of oscillation can be used to measure rotation of Earth around its own axis, around the sun, everything. But the question is, around what is the Foucault pendulum measuring Earth's rotation with respect to? That is, finally what is the Earth rotating around/revolving around? Isn't it intriguing that the effect of the entire Universe on Earth can be measured by a pendulum? I understand that the effect on the pendulum due to say the revolution of solar system around the galaxy is going to be small, but still, it can be measured say in an experiment going on for 10 years. You can keep on increasing the accuracy by measuring for longer periods.


I want to create an alias, that can be defined on any command and concats | lolcat to it. So far I googled myself to   alias MyCommandName='f(){"$@" | lolcat; unset -f f};f'   but when I test it with dmesg I get no result.  # set dmesg alias dmesg='f(){"$@" | lolcat; unset -f f};f' #desired command: dmesg | lolcat dmesg   In my understanding the alias defines a function f, that is called afterwards. To prevent recursion, the last statement is to unset the function.  EDIT: I stopped at:      alias MyCommandName='f(){eval "$@ | lolcat"; unset -f f};f'      alias MyCommandName='f(){eval "$0 $@ | lolcat"; unset -f f};f'   which does not the trick, because i can't pass the $0 argument into my function. The $0 is always f inside of the function. a generic aliaslias like is NOT possible. :(  NOT A DUPLICATE of , because I am using ZSH and argument passing is possible according to like 10 other answers like  and  :).

I want to create an alias for curl which automatically writes the file it curls into a file with the same name in the current directory.  For example:  % curl https://bootstrap.pypa.io/get-pip.py     curl https://bootstrap.pypa.io/get-pip.py > get-pip.py   Is there a way to make the alias read the following argument and insert it into the actual executed script like this?


After WWII (Wizarding War II), who went to teach each one of the classes?   Minerva Mcgonagall became the Headmistress, and IIRC the DADA teacher is no longer present (having been replaced by Voldemort to Dark Magic classes) so who takes her and the other teachers' places when the whole ordeal is over?  Update: This asks about all of the teachers including DADA, and is more broad as a question than a single teacher. For instance Professor Trelawney is sacked by Umbridge, but does she resume upon the rehashing of the school staff?

Seeing that Defense Against the Dark Arts is a crucial subject, both in Harry's life as well as a part of the school-going wizard's curriculum, it must be in the hands of a good professor.   Is it known who Minerva McGonagall appointed as DADA prof. once she was made Headmistress. Was it someone we know or was it just a random powerful wizard. Is there any information about this available?


The difference between Shonen'ai and Yaoi .   However, I encountered a few more terminologies concerning anime and mangas referring to masculine homosexuality :   Shōnen'ai JUNE Yaoi Boys' love   What are the main differences between those genres?

Yuri and Shoujo-ai are anime themes which are related to girl-to-girl relationship, while yaoi and shounen-ai are related to boy-to-boy relationships. But what are their distinct difference? When can you call a specific girl-to-girl anime a yuri or shoujo-ai? When can you call a specific boy-to-boy anime a yaoi or shounen-ai?  Plus, what is the distinct difference of ecchi and hentai anime? I just know that they are both for adults only-theme anime. When can you call a specific anime an ecchi or hentai?


My husband's and my phones both ring when either one is called.  How do we unlink them?

Why is my phone ringing when someone calls my husbands phone? The number shows up on my phone and says "from your iPhone".


I can no longer mediate and completed the main missions upto reaching Skellige. It started at some point at reaching Novigrad at first I thought it was related to the Hatori Swords and Dumplings mission however this does not seem to be the case as I finished that mission without issue.

Whenever I try to meditate on the Whitcher 3 it says "you cannot do this now". Any help? I'm not on a horse or anything I'm just in the city of Novigrad and I can't meditate.


I have this d-link router, it's original power supply was 5V and 1.2A, but I found a 5V 1A supply.  It is working, but does it represent a risk to use it? What could happen?

Power supplies are available in a wide range of voltage and current ratings.  If I have a device that has specific voltage and current ratings, how do those relate to the power ratings I need to specify?  What if I don't know the device's specs, but am replacing a previous power supply with particular ratings?  Is it OK to go lower voltage, or should it always be higher?  What about current?  I don't want a 10 A supply to damage my 1 A device.


Due to Einstein's equivalence principle, I think this is not the case. In the Liénard–Wiechert potential (which describes the em radiation of accelerated charge) I do not see the source for the acceleration - but it has to be there since otherwise, it would be independent of the source (gravitational source or electric/magnetic field). So, my question is - where in the Liénard–Wiechert potential is the source for the acceleration, and would another source (gravitation) cause the same effect?

A charged particle undergoing an acceleration radiates photons.  Let's consider a charge in a freely falling frame of reference.  In such a frame, the local gravitational field is necessarily zero, and the particle does not accelerate or experience any force. Thus, this charge is free in such a frame. But, a free charge does not emit any photons. There seems to be a paradox. Does a freely falling charge in a gravitational field radiate?


The thing is, I am looking for a codeline which can import a txt file which is in the same folder as the .jar. The only problem is, the path where the jar and the txt file will be is unknown. So I am searching for a method which can return me the path of the .jar file which is at the same time the path of the txt. But it has to work with an outstanding .jar file and not only in console. Would appreciate some helpful answers because I tried so many not working ways until now.

My code runs inside a JAR file, say foo.jar, and I need to know, in the code, in which folder the running foo.jar is.  So, if foo.jar is in C:\FOO\, I want to get that path no matter what my current working directory is.


A php script is sending tons of emails. I want to detect what is the source. All emails are sent by the use www-data which the user used by apache. When I check process, I have this result :  www-data 16220  0.7  4.7 402508 95924 ?        S    09:37   0:06 /usr/sbin/apache2 -k start www-data 16352  0.4  3.8 402132 78064 ?        S    09:39   0:03 /usr/sbin/apache2 -k start www-data 16725  0.6  3.8 402472 78624 ?        S    09:46   0:02     /usr/sbin/apache2 -k start www-data 16840  0.8  4.2 410744 87204 ?        S    09:48   0:01 /usr/sbin/apache2 -k start www-data 16949  1.0  4.5 417560 93436 ?        S    09:49   0:01 /usr/sbin/apache2 -k start www-data 16958  1.0  3.5 402120 72748 ?        S    09:50   0:01 /usr/sbin/apache2 -k start www-data 16978  1.2  4.6 425160 94864 ?        S    09:51   0:00 /usr/sbin/apache2 -k start www-data 16980  0.8  3.5 402140 72208 ?        S    09:51   0:00 /usr/sbin/apache2 -k start www-data 16983  0.4  2.6 402160 54400 ?        S    09:51   0:00 /usr/sbin/apache2 -k start   Apache is using many processes and I don't know what is the script that send mail.  Is there a way to do that?

This is a  about Server Security - Responding to Breach Events (Hacking)   See Also:                  Canonical Version I suspect that one or more of my servers is compromised by a hacker, virus, or other mechanism:   What are my first steps? When I arrive on site should I disconnect the server, preserve "evidence", are there other initial considerations? How do I go about getting services back online? How do I prevent the same thing from happening immediately again? Are there best practices or methodologies for learning from this incident? If I wanted to put a Incident Response Plan together, where would I start? Should this be part of my Disaster Recovery or Business Continuity Planning?   Original Version       2011.01.02 - I'm on my way into work at 9.30 p.m. on a Sunday because our server has been compromised somehow and was resulting in a    attack on our provider. The servers access to the Internet   has been shut down which means over 5-600 of our clients sites are now   down. Now this could be an FTP hack, or some weakness in code   somewhere. I'm not sure till I get there.      How can I track this down quickly? We're in for a whole lot of   litigation if I don't get the server back up ASAP. Any help is   appreciated. We are running Open SUSE 11.0.            2011.01.03 - Thanks to everyone for your help. Luckily I WASN'T the only person responsible for this server, just the nearest. We managed   to resolve this problem, although it may not apply to many others in a   different situation. I'll detail what we did.      We unplugged the server from the net. It was performing (attempting to   perform) a Denial Of Service attack on another server in Indonesia,   and the guilty party was also based there.      We firstly tried to identify where on the server this was coming from,   considering we have over 500 sites on the server, we expected to be   moonlighting for some time. However, with SSH access still, we ran a   command to find all files edited or created in the time the attacks   started. Luckily, the offending file was created over the winter   holidays which meant that not many other files were created on the   server at that time.      We were then able to identify the offending file which was inside the   uploaded images folder within a  website.      After a short cigarette break we concluded that, due to the files   location, it must have been uploaded via a file upload facility that   was inadequetly secured. After some googling, we found that there was   a security vulnerability that allowed files to be uploaded, within the   ZenCart admin panel, for a picture for a record company. (The section   that it never really even used), posting this form just uploaded any   file, it did not check the extension of the file, and didn't even   check to see if the user was logged in.      This meant that any files could be uploaded, including a PHP file for   the attack. We secured the vulnerability with ZenCart on the infected   site, and removed the offending files.      The job was done, and I was home for 2 a.m.            The Moral   - Always apply security patches for ZenCart, or any other CMS system for that matter. As when security updates are released, the whole   world is made aware of the vulnerability.   - Always do backups, and backup your backups.   - Employ or arrange for someone that will be there in times like these. To prevent anyone from relying on a panicy post on Server   Fault.


Why I am getting the following error /tmp/ccuWdVB3.o: In function `test': MyCode.c:(.text+0x1c): undefined reference to `sqrt' collect2: error: ld returned 1 exit status   MyCode.c #include<stdio.h> #include<math.h>  int test(int input1) {    int x = 8;   int z = sqrt(x);      }  int main(int argc, char * a[]) {  }   when running with command: gcc -o a.out -lm MyCode.c  But when I am running the command gcc MyCode.c -o a.out -lm  everything works fine. Why the order of "MyCode.c" cli option is important here ? Or Am i doing something wrong?

Why does the order in which libraries are linked sometimes cause errors in GCC?


I recently learned about set exponentiation $B^{A}$, that is, $B^{A} = \left \{ f \mid f:A\rightarrow B \right \}$ which is the set of all the functions which maps A to B. The number of function in a set exponentiation is given as $ \mid B \mid ^{\mid A \mid}$. Let consider these sets S = {1,2,3} and T = {4,5}, then according to set exponentiation there are  $2^3=8$ functions which map the above sets S to T. Question 1: Can you please provide a simple example function which maps the above sets S and T?  else can you provide another example for the same? Question 2: How mathematicians proved the number of functions in set exponentiation is $ \mid B \mid ^{\mid A \mid}$ ?

In my discrete mathematics class our notes say that between set $A$ (having $6$ elements) and set $B$ (having $8$ elements), there are $8^6$ distinct functions that can be formed, in other words: $|B|^{|A|}$ distinct functions. But no explanation is offered and I can't seem to figure out why this is true. Can anyone elaborate?


I'm new to Python and tried to make a simple program that prints out the Square roots of given numbers. However it prints the 3rd line with a small identation. I'd like to know what causes this.  Not sure what to do at this point. I'm still quite new to this.   import math  a = 4; b = 9; c = 16 print("Zahl\t\tWurzel") print(a, "\t\t\t", math.sqrt(a), "\n",       b, "\t\t\t", math.sqrt(b), "\n",       c, "\t\t", math.sqrt(c)) user_in = input("Bitte geben Sie eine Zahl ein: ") print("Die Wurzel ist: ", math.sqrt(int(user_in)))   Zahl        Wurzel 4            2.0   9           3.0   16          4.0

In python, if I say  print 'h'   I get the letter h and a newline.  If I say   print 'h',   I get the letter h and no newline.  If I say  print 'h', print 'm',   I get the letter h, a space, and the letter m.  How can I prevent Python from printing the space?  The print statements are different iterations of the same loop so I can't just use the + operator.


I have an orthographic camera to capture a plane of width 1. When I set Orthographic Scale to 1,  the camera captures 1 unit of the space in the height dimension.  Can I change the "major dimension" that Orthographic Scale affects?

I'm using 3d to speed up production of 2d graphics of machines and structures (which have a lot of straight lines, objects and little details repeated all over the place).  The goal is to have an isometric background image that repeats seamless. I set the camera with orthographic projection and 45° of rotation.    And manually cut the vertical borders in an image editor in the position where it repeats. Then I can do something like this:    Instead of cutting it manually every time I do a test, I would like to set the camera view position and height from Blender. Then I can render an already seamless repeated image.  Those two Empty objects in the boundaries are where the camera borders should be. However I have no clue how to accurately set up the camera in this case. How can I do this?


I have a lot of shapefile or fgdb feature classes that I am working with now and it gets updated almost every month.  As of right now, I am just making the file name with extra name after '-' (i.e., road_network_Jan2018_v1, road_network_Jan2018_v2, ... road_network_Feb2018_v1, and so forth)  I was wondering will there be an awesome spatial data versioning software that can improve efficiency of my works.  I am usually edit stuff uing ArcMap and QGIS and import them to PostGIS

Does anyone of you know a QGIS-Plugin for Versioning PostGIS-Data? I know there was pgVersion of Horst Düster but as far as I know this was not updated for QGIS 2.x (at least not for the "normal" QGIS aside from QGIS Enterprise. The searched functionality is: Setting up versioning for a Layer Managing conflicts that were detected (resulting from concurrent editing)  old Plugin pgVersion:


I was just watching Harry Potter "Prisoner of Azkaban". Just before the scene where Harry casts the patronus spell to get rid of the Dementors, Hermione says:     Only a really powerful wizard could have conjured it.   I know the scene is a little bit different from the book where Hermione isn't with Harry at that point, but either way the question is the same.   At that point was Harry a really powerful wizard?   What does "really powerful wizard" mean?  Could the part of Voldemort inside of Harry have enhanced Harry's powers to help him cast the patronus charm even though Voldemort himself doesn't cast that particular spell?

Harry noted to Dumbledore that he had a number of things in common with Voldemort. And it was later revealed that some of Voldemort's power was transferred to Harry when Voldemort tried to kill him. So, what powers did Harry get from Voldemort (i.e. Parseltongue and others) and did they all leave him when he stopped being a horcrux?    Update In the Chamber of Secrets Dumbledore states that Harry has many qualities that Salazar Slytherin values in his hand picked students. Parseltongue - resourcefulness - determination - a certain disregard for rules.    So, does anyone know what specific powers Harry got from Voldemort and is there anyway to tell if he lost anything else besides Parseltongue?


The question title is vague, because I don't know how to describe my it.   Given the following code:  String getLargeText() {     // loads a large text from somewhere     // and returns it }  Vecor<String> tokenize(String text) {     // seperate the text into tokens and     // return them as a vector of strings }   public static void main(String[] args) {     String text = getLargeText();       for(String token : tokenize(text)) {         // some action with 'token'     } }   Will the 'tokenize' function in the foreach-loop be called at every iteration, or just once and have its return value be re-used? It looks like the kind of thing which a good compiler would optimize, but I am not sure if java does it. And if the answer to the first question is yes, will   for(volatile String token = tokenize(text)) { ...   supress that behaviour?

Consider:  List<String> someList = new ArrayList<String>(); // add "monkey", "donkey", "skeleton key" to someList     for (String item : someList) {     System.out.println(item); }   What would the equivalent for loop look like without using the for each syntax?


This question is inspired by .     Find all nonnegative integers $m$ and $n$ such that $m!+1=n^2$.   We know that $(m,n)=(4,5)$, $(m,n)=(5,11)$, and $(m,n)=(7,71)$ are solutions.  Are there more solutions?  Are there only finitely solutions?

One observes that  \begin{equation*} 4!+1 =25=5^{2},~5!+1=121=11^{2}  \end{equation*} is a perfect square. Similarly for $n=7$ also we see that $n!+1$ is a perfect square. So one can ask the truth of this question:   Is $n!+1$ a perfect square for infinitely many $n$? If yes, then how to prove.


Say you have $n$ different, non-normal, potentially overlapping data sets of samples. Maybe their densities look something like:    and you are given a new sample $x$, how would you decide to which of these sample sets it would most likely belong?  I would assume it is possible to do a (kernel) density estimation of each of the sample sets, interpolate them to functions $p_n$, and then calculate $p_n(x)$ for each, selecting the one with the highest probability.   However both the decision rule and the method seem, well, off. Can anybody help me in getting a better intuition of this problem?  EDIT Say the data comes from a continuous scoring system, like a depression scale, and I have annotated data for many different subjects. So I can get the density plots for "severe", "mildly" and "non-depressed" subjects. Now I have a new sample and wish to know (based on the score) which the person most likely belongs to.

I have two distributions which are derived from 2 separate sets of data. These distributions are not normal, and it is not clear at this point if they belong to any family of known pdfs (they are not symmetric either). Given a data point, I need to decide which distribution it is most likely to belong to. If these were normal distributions, I could do usual parametric tests and go from there, but in this case I am not sure how to proceed. I searched around a bit, but I couldn't find anything, probably because I am not using the right keywords. Any help is much appreciated.  Edit to clarify: I should have mentioned that it was univariate. I might as well explain the actual problem here as well. We have time-spent data for users on websites. We also have information on whether a user liked or disliked some of those sites (about 4% of all the sites). So we know the distribution of time spent for like and dislike. An obvious question, then, is for a random user who spent x amount of time, are they more likely to have liked the page or dislike the page. Our time spent information is based on seconds, so the distributions are really discreet, but in real life, they are continuous.


I saw, when I posted a question on Stack Exchange/Stack Overflow, there are upvote and downvote buttons for our post. But we can't upvote nor downvote the post. Why didn't Stack Exchange remove it for our own posts?  Any reason why they didn't make the upvote button viewable for other users only? Not the user who posted the question/answer?

Currently, the system makes you think you can upvote/downvote your own question/answer but then you get notified that you can't. Why have the up/down vote buttons there then?   In general, if some operation is not allowed, then don't put UI for that up or make it disabled so it is apparently disabled - no post operation error panels please?  ps: hope this is not a dupe, but if so, just comment it and I will remove  (+a joke: a user notification panel message: I deleted this file. Is this a problem? Yes/No.)


Ok, so I posted this up in this thread () but was instructed to post it up as an individual question. I get the answers in the previous thread but wanted more clarification on the subject.  I am fairly new to css, so the conversation over DIV and CLASS interests me. I have built a site using wordpress which has allowed multiple ID's. I am interested if there really is anything wrong with this? For example, this code displays four boxes in two columns, two rows within the container...
     <div id="sub_container"
     <div id="sub_container"
     <div id="sub_container"
     <div id="sub_container"
   If I have specific styling that is different to the WP theme, obviously then it can be applied to the div or the class?  So in the case above I might have  #sub_container {background: #ffffff; position: relative; float: left;}   So I want to figure is this OK? If not, what is the benefit of having the sub container as a class rather than a div? I get the 'unique' argument, but if this works fine, why not use it?  In my code I have used classes for some headings and sections where I want specific formatting that varies from the built in formatting, but that's about it..  ..I figure I would use class if I wanted to apply different styles to the sub_container div? e.g. might want the second one to have red fonts, or have the boxes a different size on another page etc etc?

What's the difference between
 and
 when it comes to CSS? Is it alright to use
?  I see different developers doing this in both ways, and since I'm self taught, I've never really figured it out.


How do I show that $X = \left\{ (x,y) \in \mathbb{R}^2 \mid x \in \mathbb{Q}\text{ or }y \in \mathbb{Q}\right\}$ is path connected?    Note that $X$ is a topological space with subspace topology $\tau = \left\{ U \cap X \mid U\text{ is open in }\mathbb{R}^2\right\}$.  I only know two things (with respect to path connectedness):   A topological space $X$ is path connected iff for every $p,q \in X$, there is a continuous function $f: [a,b] \to X$ with $f(a)=p$ and $f(b) = q$.    Continuity $f$ is defined as for every open set in $X$, its preimage is open in $[a,b]$ (with subspace topology induced by $\mathbb{R}$ (with standard topology) )   Suppose $X$ and $Y$ are two topological spaces and $f: X \to Y$ is a continuous surjection. If $X$ is path connected, then $Y$ is path connected.

If I want to prove that $\mathbb{R} \setminus \mathbb{Q}$ is disconnected, does it suffice to say that there are two open disjoint sets that cover $\mathbb{R}\setminus\mathbb{Q}$, namely:  $$(- \infty, 0), (0, \infty)\text{ ?}$$  Along the same lines, I want to prove or disprove that $S = \mathbb{R}^2 \setminus \mathbb{Q}^2$ (points $(x, y) \in S$ that have at least one irrationais connected. I feel that it is also disconnected; does it suffice to say that there are two open disjoint sets that cover $S = \mathbb{R}^2 \setminus \mathbb{Q}^2$, namely $((- \infty, - \infty), (0, 0))$ and $((0, 0), (\infty, \infty))$? (Very iffy on my assertion and my notation, sorry.)  Thanks!


I have a webapp that is a customized Google Map; it's an interactive map of the Paris Metro.  In Google's SERP, the only thing that appears beneath the domain name is "Sorry, we have no imagery here", which is really not helpful. Here's how it looks like:   I believe this text comes from Google Maps. I tried to set the  <meta name="description"   and  <noscript>   elements, to no avail. What else should I do? Ideally I'd like to have the text in the meta/description tag show up in search results; but having nothing would be better than "Sorry, we have no imagery here"...  The site itself is here:   PS: it seems some of Google's own pages suffer from the same problem ( or  for example, found )...

I have a site with Google Maps on most of the pages. When inspecting content keywords in Google Webmaster tools, content keywords identified by Google-bot for the site include "imagery", "sorry" and "here". These turn out to be part of an error message returned by Google Maps: "Sorry, we have no imagery here". I cannot reproduce this error with normal clients, nor does "fetch as Google" show it. The problem is presumably that Google-bot tries to execute some of the Google Maps Javascript but then shoots itself on the foot and records the error message.  A  shows that this problem is endemic to sites across the internet, including Yelp and many others.  I'd like to convince Google that my site is not about imagery and being sorry, but I'd also like to keep the maps in place. I guess one option would be to transition to , but that's not a great alternative.  There's some , no resolution.


Whether we can have a form inside another form?. Is there any problem with that.

Is it possible to nest html forms like this  <form name="mainForm">   <form name="subForm">   </form> </form>   so that both forms work? My friend is having problems with this, a part of the subForm works, while another part of it does not.


This is for SQL Server 2012 Express. Please see the statements below - they are part of a view creation.   SELECT      PE.*, ZOTable.DOCNAME AS 'ZO_DOCNAME', SOR.DOCNAME AS 'SoR_DOCNAME' FROM      dbo.TAXPARCEL_EQUALIZER AS PE,      dbo.ZONINGORDINANCE AS ZOTable,      dbo.SCHEDULEOFREGULATION AS SOR LEFT JOIN      dbo.TAXPARCEL_EQUALIZER AS te1 ON ZOTable.UNIT = te1.UNIT  LEFT JOIN      dbo.TAXPARCEL_EQUALIZER AS te2  ON SOR.ZONECLASS = te2.ZONING1 LEFT JOIN      dbo.TAXPARCEL_EQUALIZER AS te3  ON SOR.ZONECLASS = te3.ZONING2   I am getting error      Multipart identifier cannot be bound    on ZOTable.UNIT inside SQL Server Management Studio.  I have looked online but can't find any example to fix mine. If I were to remove the ,  dbo.SCHEDULEOFREGULATION AS SOR then the error goes away. But then I am not sure how to bring that table into the view?  Thanks!

I continually get these errors when I try to update tables based on another table. I end up rewriting the query, change the order of joins, change some groupings and then it eventually works, but I just don't quite get it.  What is a 'multi-part identifier'? When is a 'multi-part identifier' not able to be bound? What is it being bound to anyway? In what cases will this error occur? What are the best ways to prevent it?    The specific error from SQL Server 2005 is:     The multi-part identifier "..." could not be bound.   Here is an example:  UPDATE  [test].[dbo].[CompanyDetail]  SET Mnemonic = [dbBWKMigration].[dbo].[Company].[MNEMONIC],                 [Company Code] = [dbBWKMigration].[dbo].[Company].[COMPANYCODE]  WHERE [Company Name] = **[dbBWKMigration].[dbo].[Company].[COMPANYNAME]**   The actual error:     Msg 4104, Level 16, State 1, Line 3 The multi-part identifier   "dbBWKMigration.dbo.Company.COMPANYNAME" could not be bound.


Why do javascript return a true value if I check the following equation:  console.log(Number.MAX_VALUE === (Number.MAX_VALUE - 1)); // -> true   It doesn't matter if I add or subtract a certain value of the max value. Even a big number like 100000 will return true.  console.log(Number.MAX_VALUE === (Number.MAX_VALUE - 100000)); // -> true   I would appreciate any answer, thank you very much.

Is this defined by the language? Is there a defined maximum? Is it different in different browsers?


I tried to do this in the terminal sudo apt-get install google chrome  but the package does not exist please help

I am trying to install chrome browser via command line.  I tried this:  $ apt-cache search chrome browser   The results show that the proper term is "chrome-browser," so I tried that:  $ sudo apt-get install chrome-browser   And then "Y" for the Y/n question.  But the installation threw errors.  Does someone see anything wrong with the commands I issued?


Q: Is the italicised verb form correct in this sentence?      Jane's pale face suggested she could be ill: her parents suggested   that she have a medical examination.      A: The sentence is grammatically correct. The subjunctive remains in   force even though it is likely the patient will follow the doctor's   advice. To actualize the blood test with "has" would be telling an   untruth. The subjunctive holds the notion of a suggestion in place.   Thus does grammar make its own modest contribution to truthful   speaking.   I don't see how this sentence can be grammatical. Please could you offer any comments.

Why is this sentence correct?     She suggested that he go to the cinema.   I would definitely use goes instead of go.


Let's look at these two sentences:  Color blindness affects 8% of men. That sandwich costs $8.  So why, when using the percent symbol do we put it after the word, but with money we place it before the word?

$1,000 is pronounced as "one thousand dollars". Reading from left to right, it seems like it would make more sense to write the value as: 1,000$. This way the pronunciation of the value follows the way it's written. Every other numerical value I can think of places the unit after the value:   1 kg 1 L 1 m, etc...   I'm not sure if this question fits in with the rest of the questions on this site. But I'd like to know why currencies are so different from other quantities. Not to mention the need to separate groups of three digits with commas.


I know that determinant as a map from set $n×n$ matrices to $\Bbb{R}$ is an open map but I wonder whether it is closed map too?I don't know how to prove or disprove but intuitively it seems to me that it is not closed.Any help is appreciable Thanks.

The determinant function $\det:M(n,\mathbb R)\rightarrow \mathbb R$ is an open mapping or a closed mapping?  The determinant function $\det:M(n,\mathbb C)\rightarrow \mathbb C$ is an open mapping or a closed mapping?


I successfully retained my data on orientation change using savedInstanceState. However I can't update it to the ui. I tried overriding the onStart() method. But UI is not updating with the data on orientation change. Can somebody help me fix it. I want to display the data on orientation change. The ui somehow doesn't update unless the onStart() is forced after orientation change by pressing home button or switching to app list. I'm using viewpager + fragments.

I've been working on the Android SDK platform, and it is a little unclear how to save an application's state. So given this minor re-tooling of the 'Hello, Android' example:  package com.android.hello;  import android.app.Activity; import android.os.Bundle; import android.widget.TextView;  public class HelloAndroid extends Activity {    private TextView mTextView = null;    /** Called when the activity is first created. */   @Override   public void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);      mTextView = new TextView(this);      if (savedInstanceState == null) {        mTextView.setText("Welcome to HelloAndroid!");     } else {        mTextView.setText("Welcome back.");     }      setContentView(mTextView);   } }   I thought it would be enough for the simplest case, but it always responds with the first message, no matter how I navigate away from the app.  I'm sure the solution is as simple as overriding onPause or something like that, but I've been poking away in the documentation for 30 minutes or so and haven't found anything obvious.