Multiple for-loops break in Python
How to break out of multiple loops?
java.io.IOException: An existing connection was forcibly closed by the remote host Upon entering any given minecraft server, after a minute or two I am forced out of the server, and I'm given the following error:  java.io.IOException: An existing connection was forcibly closed by the remote host.  What does this mean, and how can I prevent it from happening again? Strictly diagonally dominant matrices are non singular If the electric field is the gradient of the potential, then can we say that whenever potential is zero, the electric field is zero? For example, in a dipole, at the center of the two charges making up the dipole, the potential is zero but the electric field is non-zero. But if $E = -\operatorname{grad}V$, then why is $E$ not zero?  Another example: In the case of two positive charges, the electric field is zero at the mid-point of line joining them, but potential is non-zero. What am I misunderstanding here? Why does an electron shell further away from nucleus has higher energy level? Using electrical potential energy $V=\frac{1}{4\pi \varepsilon_0} \frac{Q_1 Q_2}{r}$ , a particle further away from nucleus has lower magnitude of energy.  Using Coulomb's law, a particle further away from nucleus experiences weaker attraction, hence less energy is needed to maintain orbit$^\star$ around that e-shell compared to a electron shell closer to nucleus, hence the one closer to nucleus supposedly should have higher energy.  $^\star$I know in reality $e^-$ does not orbit around a atom, but its position exists as a probability density or radial probability function. Show that: $\lim\limits_{r\to\infty}\int\limits_{0}^{\pi/2}e^{-r\sin \theta}\text d\theta=0$ I would like to show $\lim\limits_{r\to\infty}\int_{0}^{\pi/2}e^{-r\sin \theta}\text d\theta=0$.  Now, of course, the integrand does not converge uniformly to $0$ on $\theta\in [0, \pi/2]$, since it has value $1$ at $\theta =0$ for all $r\in \mathbb{R}$.   If $F(r) = \int_{0}^{\pi/2}e^{-r\sin \theta}\text d\theta$, we can find the $j$th derivative $F^{(j)}(r) = (-1)^j\int_{0}^{\pi/2}\sin^{j}(\theta)e^{-r\sin\theta}\text d\theta$, but I don't see how this is helping.  The function is strictly decreasing on $[0,\pi/2]$, since $\partial_{\theta}(e^{-r\sin\theta})=-r\cos\theta e^{-r\sin \theta}$, which is strictly negative on $(0,\pi/2)$.  Any ideas? Getting 2-factor Gmail authentication code from Sweden mobile number I have been facing a serious problem for many months. Usually I get a 2-factor authentication code from 51501 when I am supposed to log into Gmail. But for months I am getting a code from a Sweden-based mobile number: +46701327805. The first code I received from this number was in October 2015.  There is also a mobile number from USA that sometimes sends the code. I change my passwords every time this happens. What could be the possible reason for this and how to overcome this problem?   By the way, I must say I have been hacked for years. I don't use VPN; my internet runs off a broadband modem. Ubuntu 14.04 has visual artifacts and freezes Error 404 : While using flag Recently on Stack Overflow I got privilege to flag a post. So when I try to flag a post as duplicate. The diaglog box is not properly loading.         However I am easily able to use other flag option like "other","spam" or "offensive".   "other"        "spam"        "offensive"        I am using Google Chrome Version 28.0.1500.71 and Win XP Operating System. I have tried in firefox as well but it is showing me same problem. : So how many named special cases of each modal verb are there, in toto? There's   1. subjunctive should, and   2. mandative should, and   3. , at least;   and I s[up]pose 4. Should we? is suggestive should, and   5. Shouldn't we? is tag **should**, and I can think of a lot more.    I ask about only operative uses of this modal verb including literary and formal usage,  but please omit anything obsolete. I'm trying to classify them and learn the formal terms describing each. Are there any apt others in addition to the ones above? (I added the enumeration below)  1. What's 'subjunctive should'?  Whenever should is conjugated in the subjunctive mood? 5. What's a tag **should** ? 6. Where does  should/would  feature? What's it called? This should is detailed in   or  or . I'm using Drupal 7.  Is it possible to add a CC to a webform email?  I was using   function theme_webform_mail_headers($variables) {   $headers = array(     'X-Mailer' =&gt; 'Drupal Webform (PHP/' . phpversion() . ')',   );   return $headers; }   changing it with      function MYTHEME_webform_mail_headers($variables) {       $headers = array( 'CC' =&gt; 'ccmeail@domain.com', 'X-Mailer' =&gt; 'Drupal Webform (PHP/'. phpversion() .')',  );       return $headers;     }   It does not work, I've cleared all the chaches and it does not add the CC. How could I add the CC?  Thanks in advance. Movement arrow in gloss I believe that umask is something that controls , but do not fully understand it.  After running umask 0644 in a , I cannot read the files I create with the command-line text editor nano. I noticed that the permissions of that file are set to 0022 instead of the default 0755.  How does umask work? I thought I could just remove the each digit in the umask from 0777, 7 - 6 = 1 and 7 - 4 = 3, so I expect the permissions to be 0133, but apparently, this is not the case.   What is umask exactly? Explain it to me like I was a "Linux noob" How do I calculate with umask? What are use cases for umask? QGIS3 - Clipping polygons to a hemisphere for azimuthal orthographic projection I'm a bit of a novice with QGIS, so this is really throwing me for a loop.  For the maps I'm intending on making, an azimuthal orthographic projection would be my preference.   For example, one map I'm trying to recreate is this map of the Pacific islands :    I've been using the NaturalEarth Quick Start package, which has been a really good launching-off point, but I'm running into some issues at the horizon of the orthographic projection.  I've tried adding a custom projection:  +proj=ortho +lat_0=0 +lon_0=170 +x_0=0 +y_0=0 +a=6371000 +b=6371000 +units=m +no_defs   But that gives the following map:    Which certainly is close to being right, but the ocean is obviously being cut off in the Arctic and on the southern horizon.  I understand the issue is that naively mapping layers described in WGS 84 to an orthographic projection leaves you with artifacts at the horizon, but how do I fix it?    I first tried to use the Clip to Hemisphere plugin described in , but it seems incompatible with QGIS 3; when I try adding the plugin, QGIS3 gives an error message and places it in the "Invalid" section of the Plugins window.    I then tried both solutions presented at  Again the issue is with QGIS 2/3 incompatibility.    For Solution 1, both Numerical Digitize and CAD Tools are again incompatible with QGIS 3 and give the same result as Clip to Hemisphere.    For Solution 2, I can't disable on-the-fly-reprojection in settings since that setting was removed in QGIS 3. What is the effect where some objects are a single bright color but the rest is black and white? There is an option to filter only one color (R,G,B,Y) in my camera. What I want to know is can this effect be achieved in photoshop? And what is this called? I tried googling monochrome and came up with nothing. My camera calls it part color. What is currently the most reliable VPN for China? I will soon be spending a few months travelling across China and want to get a VPN service to get around the Golden Firewall.   When I was in China in 2014/15 the general consensus was that Astrill offered the most reliable service, but I heard that they have been targeted quite strongly by the government over the last year.   Therefore, I am wondering what is the best VPN for China these days? Is Astrill still as good as it used to be?   Any recent experiences would be very helpful! wpf combobox binding I'm new to data mining and I'm trying to train a decision tree against a data set which is highly unbalanced. However, I'm having problems with poor predictive accuracy.  The data consists of students studying courses, and the class variable is the course status which has two values - Withdrawn or Current.   Age Ethnicity Gender Course  ... Course Status   In the data set there are many more instances which are Current than Withdrawn. Withdrawn instances only accounting for 2% of the total instances.  I want to be able to build a model which can predict the probability that a person will withdraw in the future. However when testing the model against the training data, the accuracy of the model is terrible.  I've had similar issues with decision trees where the data is dominated by one or two classes.  What approach can I use to solve this problem and build a more accurate classifier? Many of the UK visa refusals we see here share a common pattern and the prevailing reasons refer to V 4.2 (a) and (c).    I do understand that, while the applicants may describe very different individual circumstances, there's a consistent pattern and, broadly, fall into specific categories:    Credibility (lifestyle, lack of ties, visit history, lies &amp; omissions) Funding (insufficient funds, provenance of funds, funds parking) Sponsorship (family, friends, employer)   Question: What most commonly triggers a UK visa refusal where V 4.2 (a) and (c) are given as the grounds?  Secondarily: Given that there is a clear pattern, to what extent are these refusals predictable? Does sponsorship make a difference? Is there a set of personal circumstances, however abstract, where a refusal is all but guaranteed? For example, why do those we see here on TSE who sought entry for the PLAB or British Army appear to be refused with a common theme? Is there a uniform shortcoming or is it just discrimination?   PLAB: What is about applications for a visa, for the purpose of sitting the Professional and Linguistic Assessments Board (PLAB) exam, that seem to invite refusals. After all, the test is given so that international medical graduates can show that they qualify to practise medicine in the UK. The first part, PLAB 1, can be taken in centres outside of the UK. However, PLAB 2 can be taken only in the UK. Why can't you can't get a visa just to sit the exam, promising that you'll leave immediately after?    British Army: Since Commonwealth citizens are eligible to apply online to join, even those who don't reside in the UK, why is it so difficult to get a visa just to attend an interview to see whether you are suitable? Even with an invitation from the Army, such visa applications seem to be unsuccessful. Isn't a career in the British Army a valid reason?     Lastly:  After such a refusal, what approaches would increase the chance of a successful application? 13.04 - more than four workspace shortcuts in GNOME Flashback (No effects) I'm using GNOME Flashback (No effects) on Ubuntu 13.04 and I've got six workspaces however when entering System Settings -> Keyboard -> Shortcuts -> Navigation I only see options to address the initial four.  It used to be options up to 12 workspaces there and as I certainly don't need that much, I want to have at least enough for the amount currently active.  How can I restore or add more shotcuts specifically to navigate and move windows to workspace 5 and 6? Do I need to re-check my bags when flying into the US on a transit through Newark Airport? Travveling with SAS 907 from Oslo, Norway to Newark Terminal B. Transfer to Terminal C and further with United 239 to Nashville. Do I have to pick up the luggage at terminal B and bring it to terminal C?