I'm unable to retrieve the amulet fragment of the Gauldur Amulet in Geirmund's Hall. This most likely is the result of me clearing the dungeon without the quest a couple of hours ago and perhaps not picking up the quest item back then. Anyway, the waypoint leads me to a place in the shallow water of the bossfight chamber and indicates something to pick up but it isn't there.  Can anyone please help me and tell me how I can solve this problem?

I am having trouble retrieving the Gauldur amulet fragment from Geirmund's Hall after clearing it before I was aware of this quest. Now when I return the quest indicator points on the floor in boss' room, specifically on a patch of submerged dirt. The water is quite shallow and I am quite sure that there is nothing to pick up there.  To me it seems the quest has bugged as I killed the boss before embarking on this quest, or killed him while unaware of the quest and not picking the fragment up. How can I get around this? Is there a console command which can help me?


I've just installed (some months ago) Ubuntu 14.04 on my Asus laptop. I followed a specific guide on partitions and thought everything was ok. But, beeing pretty new at this I probably made some mistake doing my partitions and now I have a nice mess.   I left 46.5 Gb for /, then 15 Gb for /home, and then 123 Gb for swap. It appears (have a look on the image of my gparted) that I also left 542 Gb for ntfs Data and 15 Gb for ntfs Restore (and don't really know if those need so much space). Also, I don't have any unallocated space and I don't know if this is good or really bad.  My question is: I don't have enough space in my /home partition (it is already 98% full) and I'd like to know how to extend it without any - apparently - unallocated space. Can I take some space from the swap or the NTFS partitions? How? I think I left them too much space..

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 have already shown (in a previous question) that $I=\langle x,2\rangle$, and that I is a prime ideal, and I believe that allows me to show that $\mathbb{Z}[x]/I$ is an integral domain, which if it is finite would allow me to conclude that $\mathbb{Z}[x]/I$ is a field, which would imply that I is a maximal ideal. But I don't know how to determine the number of elements in $\mathbb{Z}[x]/I$, and thus do not know how to determine whether or not it is finite.   Can someone tell me if this thinking is correct, and if so how to determine the number of elements in $\mathbb{Z}[x]/I$?   Note: we have not covered irreducibility in this course.

In $\mathbb{Z}\left [ x \right ]$, let $I = \left \{ f\left ( x \right ) \in \mathbb{Z}\left [ x \right ]: f\left ( 0 \right ) \text{ is an even integer} \right \}$   In fact, $I=\left \langle x,2 \right \rangle$  How do I show that the order of $\mathbb{Z}\left [ x \right ]/I$ is 2?


I deleted my Partition for Ubuntu and my Windows OS cant load. How can I load Ubuntu into a USB so I can install the boot loader on my PC ?

I have absolutely no experience with Linux, and I desperately need to get my computer back up and running again with Windows.  How do I remove Ubuntu and reinstall Windows?    Editor's note: many of the answers are about removing Ubuntu from dual-boot but keeping Windows (which is a bit complicated), while other answers are about removing Ubuntu from single-boot (which is easy: basically just format the disk while installing Windows). The question as written is ambiguous between dual-boot or single-boot.


Why is it that lenses come with an AF option when the camera has the same? Which controls the AF? One would think that they contend with each other for control. Why have two entities doing the same single task? A  photographer friend of mine said to set the lens to Manual. If every photographer does why offer lenses with this setting?

I use my DSLR (Nikon D500) for both photography and video, and I prefer autofocus for photography and manual focus for video (to get rid of autofocus noise).  There is an option for changing between the two on both the body and the lens, and obviously it is very annoying to have to keep flicking 2 switches to do the same thing all of the time.  Do you only have to change one of them, and would doing this cause any damage to the camera and/or the lens?  (I am aware that a similar question has already been asked before, however the answers said more what is "best practice" and not so much if there are any consequences to only changing one of them)  Thanks!


I tried to run a query in Stack Exchange Data Explorer without being signed in. Doing so, I was presented with a reCAPTCHA that seems to be deprecated. I was running this query:  And I see this:

According to this , I thought the new recaptcha API was used network-wide. Though today, when going to  (which for whatever reasons never recognized me automatically), I got this message instead of a usable captcha image.   V1 Unsupported Please direct siteowner to   (Doing a second try doesn't show this message anymore, and the recaptcha v1 works as intended.)  According to , the reCAPTCHA v1 API will stop working on March 31, 2018:  What happens to reCAPTCHA v1? Any calls to the v1 API will not work after March 31, 2018. Starting in November 2017, a percentage of reCAPTCHA v1 traffic will begin to show a notice informing users that the old API will soon be retired. Most websites around the world have already switched to reCAPTCHA v2, where humans pass effortlessly. With our advanced risk analysis engine, reCAPTCHA v2 can effectively separate humans from bots and always stay ahead of the attackers. If your site still uses reCAPTCHA v1, please upgrade to reCAPTCHA v2 immediately. We no longer support reCAPTCHA v1. Any calls to the v1 API will not work after March 31, 2018. Please register a new key and upgrade to v2.  I'm really hoping this will not take  to fix, because we've only got three and a half weeks left!


I've looked around and haven't been able to find a complete answer so I'll ask in case anyone has an answer or can point me to one.  I know the order isn't alphabetical, the keywords usually appear in a specific order. Take  and  for example, which puts the keyword order as:  flying, first strike, vigilance, trample, haste, and protection for Akroma   and   flying, first strike, vigilance, lifelink, and protection for the Sphinx.  As with both, it goes flying, first strike vigilance, then some other evergreen keywords, then ends with protection. So is there any distinct order that WotC follows for these?

I was reviewing the a spreadsheet I created of the RTR spoiler to prepare my strategy for this coming weekend. In doing so, I noticed that here and on previous sets if a creature has flying, it is virtually always the first ability listed on the card.  Now, I see a strong parallel between Magic card abilities and . In the same vein that a public static int is syntactically the same as a static public int, a creature that is flying, deathtouch is the same as deathtouch, flying. But you never really see the latter, only the former.  A search of the official rules didn't indicate anything, nor did Google.  Is there a canonical, conventional, or official order by which I can expect cards to have their abilities listed on the card?  Edit: I take back one comment. Faerie Invaders has Flash before Flying. Perhaps Flash is 'more important' than Flying?


I am working with a family of integrals that involve a product of cosines of the form $\prod_{k=1}^{m} \cos(2^kx)$.  Is there a formula or identity for simplifying $\prod_{k=1}^{m} \cos(2^kx)$ to a polynomial number of terms in $x$?  Or $\cos x$, $\sin x$?

$$\cos A \cdot \cos 2A  \cdot \cos 2^{2}A  \cdot \cos 2^{3}A  ... \cos 2^{n-1}A = \frac { \sin 2^n A}{ 2^n \sin  A } $$  I am very much inquisitive to see how this trigonometrical identity can be proved.  PS:I am not much of interested about an inductive proof.


I am a US citizen, convicted of a non-violent drug offense. I was sentenced to 3 years in prison. It has been 10 years since my release and completion of probation.  Can I travel to the UK?

I have a friend with a criminal record who wants to go to London with me and I'm trying to determine if that is actually a possibility.  This friend was convicted of a class A misdemeanor on Dec 14, 2011 for theft. The court disposition was deferred so they weren't sentenced to any jail time (although they were in jail shortly following their initial arrest and prior to their being bonded out). They were, however, placed on probation for two years.  Since they were never actually sentenced to jail time it seems like, per , that their visiting the UK shouldn't be a problem.


Can someone please give me a simple example(I'm not a math professional) of a categorical morphism that is not a function?

I have encountered a statement in Lang's Algebra (Revised Third Edition, page 53) concerning morphisms of objects that seems strange to me: "In practice, in this book we shall see that most of our morphisms are actually mappings, or closely related to mappings."  I have always been under the impression that the terms 'mapping' and 'morphism' are synonymous in the context of categories. Perhaps it is just the case that Lang defines the two in a way that they disagree, but I can't find such an instance. Are they in fact different? If so, what is an example of a morphism that is not a mapping?


How do we calculate a confidence interval for a result in binary classifiers ?  CI for regression problems makes sense since we have a variable estimated output that I can calculate its estimated mean and then get the SE around it.  For classification problems, We only have metrics like Fpr/Tpr/AuC, precision/accuracy & class probabilities. Besides, class distribution is not usually approximated to a known distribution.  I am implementing a RandomForest classifier via Python for a biased binary classification problem.

For a single ROC curve (with relevant AUC score), how can you calculate the confidence interval?  (The data used to generate this ROC/AUC is available)  Given my relatively limited background in this area, this would be a case of 'the easier, the better'.  PS: please also inform me of any conditions that have to be fulfilled (if required by the formula you would use to calculate the CI).


Why can't we compress liquids when we could compress gases. My basic idea is that the bonds in liquids are not elastic. So please explain this.

What makes the two gases compressible, but does not apply to a liquid like water?


I have a Bash script which is scheduled to run everyday and sends out user notification emails using a command like:  mail -s "Hello World" someone@gmail.com  Why is this email detected as spam by Gmail. Is there something I can do so that Gmail doesn't spam the email?

This is a  about how to handle email sent from your server being misclassified as spam.  For additional information you may find these similar questions helpful:                    Sometimes I want to send newsletters to my customers. The problem is, that some of the emails get caught as spam messages. Mostly by Outlook at the client (even in my own Outlook 2007).  Now I want to know what should be done to create "good" emails. I know about reverse lookup etc., but (for example), what about a unsubscribe link with an unique ID?  Does that increase a spam rating?


\documentclass[a4paper,12pt,numbers=noenddot]{scrartcl} \usepackage{titling} \usepackage[T1]{fontenc} \title{Validation of Numerical Simulation of Fender Tests\par} \begin{document} \begin{titlepage} \begin{center} \vspace*{3cm} \textsf{\huge{\thetitle}} \end{center} \end{document}   Output     I want some more spacing between the first line and second line of my title. I tried adding \vspace, \\, \newline after the word 'Beer' but nothing works.

If I type something like this:  {\itshape\LARGE   Dunt venim dolorerosto do odit   ametum vulla conum dolore   conulput in vero od el   Dunt venim dolorerosto do odit   ametum vulla conum dolore   conulput in vero od el }   it results in a block of 4 lines with narrow spacing between the 1st and 2nd line and between the 3rd and 4th line. Line spacing between the 2nd and 3rd line is normal.  I can't fully explaing it to myself so I am looking for a short description for this behaviour. I know for example that with a \par at the end of the text (inside the group), the calculation would correct. But I have no idea why...


I have the following two invocations of a function in bash, which I'm piping to another function which captures the error output:  >&2 log_stdout | log_err  log_stdout >&2 | log_err  Is there any semantic difference between the two?   Edit: The suggested duplicate, while having an awesome community wiki, does not provide an answer to this specific question.

I often see tutorials online that connect various commands with different symbols. For example:  command1 |  command2 command1 &  command2 command1 || command2     command1 && command2   Others seem to be connecting commands to files:  command1  > file1 command1  >> file1   What are these things? What are they called? What do they do? Are there more of them?    .


I read that there is 2 type of group of order 4. 1. Cyclic group of order 4 and 2. Klein-4 group.  My question is $Z^*_5$ does not seem to fit either one of it by just looking at the table of operation but then why is it a group? Did I miss any thing or does it actually isomorphic to one?  Thank you the comment below so as you ask me, here is the . The problem is I don’t see why is $Z^*_5$ under multiplication isomorphic to $Z_4$ under addition. And it would be very kind if someone can provide such bijection for me to be crystal clear to me. Thanks again!  And well, what I mean by looking the same and different is like 0 in $Z_4$ playing the same role as 1 in $Z^*_5$ ,which generator in $Z_4$ is playing the same role as which in $Z_5^*$ and vice versa.

I think its silly question but I have nt this in my mind at this time.   Any one can help  How we can see $U(10) \overset{def}= \{1,3,7,9\}$, $\mathbb Z/4\mathbb Z \overset{def}= \{0,1,2,3\}$, $U(5) \overset{def}= \{1,2,3,4\}$ are isomorphic groups where $U(10)$ and $U(5)$ are groups under multiplication?


When visiting any Stack Exchange site's mobile version from an Android device, the view counter is not displayed.  However, it is there on the full site view.

I often use Stack Exchange sites from my smartphone. It works great, but I always have to switch to full version to see view counts of a question. Can you please add it? There's plenty of space on question page for it to place. I request community to suggest a location.


Google search console reported that some pages have a Mobile Usability issues:  Clickable elements too close together Content wider than screen Text too small to read  Some details:  this is not about restrictions in robots.txt some failed pages have less than 8 resources with 550KB size total the failed pages make up a small part of the total and are random "LIVE TEST" for the same URL may fail randomly there is no network problems (packet loss/response time/DNS) with the server where site deployed this issue appeared since April 14th most of the failed pages have 90-99% mobile performance in PageSpeed Insights or Lighthouse  Lighthouse embedded in the Chrome and  haven't found a problem in mobile mode in the same pages that have an issues in Google search console. But when I use "LIVE TEST" for failed URLs in Google search console, sometimes I get a same failed result with Mobile Usability issues, where CSS file not loaded with a reason "Other error". I think this is an issues reason but I don't understand what can I do to fix it, especially if it is due to some netiquette limitation (crawl budget)

I get the error "Couldn't load 23 page resources" when doing the mobile friendly test at     However, the error message is (the rather unfriendly) "Other error."  When I visit the site in Chrome using Developer Tools and setting the device toolbar to "Responsive," it works fine with no errors, and when I go the Google Search Console and do Crawl->Fetch As Google, I get no errors.


help!!I installed Ubuntu 14.04 and then upgraded to 14.10 but when I perform sudo apt-get update in the terminal this error occurs.  how to fix this kind of error?  I already changed the default URI in the source.list to other site/mirror but always the same error.  W: Failed to fetch http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu/dists/utopic/main/binary-amd64/Packages  404  Not Found W: Failed to fetch http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu/dists/utopic/main/binary-i386/Packages  404  Not Found E: Some index files failed to download. They have been ignored, or old ones used instead. ryanjoseph@Satellite-L635:~$

PPA seems to be constantly offline. Whenever I use sudo apt-get update, this error is shown:  W: Failed to fetch http://ppa.launchpad.net/ 404  Not Found   How do I fix these errors?


var i={ key1:value1, key2:value2 } var j={ key2:value2, key1:value1 }  How to compare above objects and get answer true?

A strict equality operator will tell you if two object types are equal. However, is there a way to tell if two objects are equal, much like the hash code value in Java?  Stack Overflow question  is similar to this question, but requires a more academic answer. The scenario above demonstrates why it would be necessary to have one, and I'm wondering if there is any equivalent solution.


I think I found a small bug. When getting an audit question, I might want to look around in the comments of that question, to see what others think, before flagging it or just clicking the "Nothing to do" button. When I do this, I'm already told that I didn't pass the test. I think this is wrong. I'm just trying to do the job as well as I can.  Additionally, I think that getting an audit question every third time is highly annoying.

So  came up. It was clearly not a crap answer, and I could tell it was probably an audit because no username was being displayed, but I wanted to read the question before deciding whether to "no action" or "skip". The question had slightly fuddled grammar so I decided to look at its comments. The comment expansion text read "show 8 more comments" (all 8 comments were hidden). I clicked it and it failed the audit.  Why should an audit based on a known good answer fail because I was attempting to get more information on the question?  Interestingly enough, several non-audit reviews I've seen replace the "add comment"/"show more comments" link with the text "comments disabled on deleted / locked posts / reviews". At the very least this text should have shown for this audit.


I look at the Stack Exchange hot questions list fairly regularly, and I can't remember ever seeing a Meta Stack Exchange question.   Is Meta blacklisted (if so, why?), or are there simply not any questions here that are hot enough to get onto the list?

Apparently MSE questions are able to appear in the hot list, which the old MSO didn't managed to. Shouldn't MSE behave the same way as the old MSO in this aspect?


I am stuck on a problem where I am given the value of $\phi(n)=31615577098574867424$ for $n=pq=31615577110997599711$ where $p$ and $q$ are prime numbers. Now, I need to find the values of $p$ and $q$ but I am not able to get an idea as to how I can solve it. I know that $\phi(n)$ gives the number of relative prime to a given number $n$ but I can use Euler-totient function to factorize $n$?

My task is to factorize $n$ knowing it has two factors and $\varphi(n)$. How can I do it?  Thanks for any advice.


I am creating an atari breakout game in processing and I'm trying to figure out the collision detection that allows the ball to bounce off the controller. The commented out lines (along with the hitController function) is supposed to be the method for this and the program runs fine without the commented lines but with them, it causes a NullPointerException. Any suggestions?  class Ball {   float rad = 15;   float xpos, ypos;   float xspeed = 2.8;   float yspeed = 2.2;   float xdir = 1;   float ydir = 1;   Controller controller;    Ball(){     noStroke();     ellipseMode(RADIUS);     xpos = width/2;     ypos = height/2;    }    void move(){     xpos = xpos + (xspeed * xdir);     ypos = ypos + (yspeed * ydir);      if(xpos > width - rad || xpos < rad){       xdir *= -1;     }     if(ypos > height - rad || ypos < rad){       ydir *= -1;     }     //boolean hit = hitController(xpos, ypos, rad, controller.getY());     //if(hit){       //xdir *= -1;       //ydir *= -1;     //}   }     void display(){     ellipse(xpos, ypos, rad, rad);     }      boolean hitController(float cx, float cy, float rad, float ry){       float testX = cx;       float testY = cy;       if(cy < ry){         testY = ry;       }       float distX = cx - testX;       float distY = cy - testY;       float distance = sqrt((distX * distX)+(distY * distY));        if(distance <= rad){         return true;       } else {         return false;       }     }    }   edit: I have included the controller class below as well.   class Controller {   int cwidth;   int cheight;   color c;   float x, y;    Controller() {     cwidth = 155;     cheight = 15;     c = color(50,10,10,150);     x = 0;     y = 0;   }    void setLocation(int x, int y) {     this.x = x;     this.y = y;   }     void display() {     x = constrain(mouseX, 70, 640 );     y = constrain(mouseY, 480, 480);      rectMode(CENTER);     fill(c);     rect(x, y, cwidth, cheight);    }    float getX() {     return x;   }    float getY() {     return y;   }  }

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?


Let me know word "-f" mentioned in apt-get -f install, what it actually denotes?     apt-get -f install

what is the usage of apt-get -f install . when I run sudo apt-get update I got some errors at the end It says try apt-get -f install. What is this command?  the last part of my error is :   . . .   going to be installed   E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).


I am trying to get this script to function correctly but I get ./passmark.sh line 7: [y command not found.  Here is my script  #!/bin/bash # A simple script to ask a user for a pass mark and then display a grade # the grade will be either an A, B, C, D or F # CONT=y echo while [$CONT = "y" ] do         echo -e "\"Please enter a pass mark: \c \""         read MARK         if [$MARK -ge "0" -a $MARK -lt "50"] ; then                 echo -e "\n \"F\" \n"         elif [$MARK -ge "50" -a $MARK -lt "60"] ; then                 echo -e "\n \"D\" \n"         elif [$MARK -ge "60" -a $MARK -lt "70"] ; then                 echo -e "\n \"C\" \n"         elif [$MARK -ge "70" -a $MARK -lt "80"] ; then                 echo -e "\n \"B\" \n"         elif [$MARK -ge "80" -a $MARK -lt "100"] ; then                 echo -e "\n \"A\" \n"         else                 echo -e "\"Invalid input!!\n \""         fi         echo -e "\"Would you like to enter another pass mark? (y/n) \c \""         read REPLY         case "$REPLY" in                 n | N | no | No | NO ) CONT=n ;;                 *) ;;         esac echo done

I am using the below script to move two days back when script runs at starting two days of the year and also check first and second days of every month and move two days back. if [$month="01"] && [$day="01"]; then         date="$last_month/$yes_day/$last_year"         fulldate="$last_month/$yes_day/$last_year" else         if [$month="01"] && [$day="02"]; then                 date="$last_month/$yes_day/$last_year"                 fulldate="$last_month/$yes_day/$last_year"         else                 if [ $day = "01" ]; then                         date="$last_month/$yes_day/$year"                         fulldate="$year$last_month$yes_day"                 else                         if [ $day = "02" ]; then                                 date="$last_month/$yes_day/$year"                                 fulldate="$year$last_month$yes_day"                         else                                 date="$month/$yes_day/$year"                                 fulldate="$year$month$yes_day"                         fi                 fi         fi fi  But my bad am getting the below error message Etime_script.sh: line 19: [06=01]: command not found Etime_script.sh: line 24: [06=01]: command not found


I´m finishing this study but I think the gliterry party is a little off, kinda blurry. Does anyone have any tip on how to improve it this final render? Thanks a lot!   I mean this part (the upload here made the image low quality somehow):  Doesn´t look sharp like this glitter image:

Something like this. Probably some kind of noise mask with some metallic, low roughness?


Is there a way to get files/directories permissions in number format "0777" instead of "-rw--r--r" format?

There is a chmod command to set file permissions, but can I get file permissions in octal mode (such as 755) from the command line?


Many times is handy to define \newcommand for short notation for \multicolumn. For this purposes I test two definition for such commands:  \newcommand\my[2]{\multicolumn{1}{#1}{#2}} \newcommand\mx[2][c]{\multicolumn{1}{#1}{#2}}   Meanwhile first definition works fine, the second throw error:  ! Misplaced \omit. \multispan ->\omit                     \@multispan  l.9 \mx{A}                 &   \mx[c|]{B}  \\   at testing with the following MWE:  \documentclass[margin=3mm]{standalone} \newcommand\mx[2][c]{\multicolumn{1}{#1}{#2}} \newcommand\my[2]{\multicolumn{1}{#1}{#2}}  \begin{document} \begin{tabular}{|c|c|}   \hline \mx{A}      &   \mx[c|]{B}  \\ \my{c}{A}   &   \my{c|}{B}  \\   \hline \end{tabular} \end{document}   Is there a way to fix definition for \mx?

I want to define a new command \tableheadline that (1) formats the headline text in some way and (2) takes an optional argument for spanning multiple columns while centering the headline.  I tried the following implementation:  \documentclass{minimal}  \newcommand{\tableheadline}[2][1]{\multicolumn{#1}{c}{\textit{#2}}} % \newcommand{\tableheadline}[2][1]{\multicolumn{1}{c}{\textit{#2}}}  \begin{document}   \begin{tabular}[\textwidth]{cc}      \tableheadline[2]{C}     \tableheadline{A} & \tableheadline{B} \\     0 & 1 \\     2 & 3 \\   \end{tabular} \end{document}   This, however, gives me an error:  ! Misplaced \omit. \multispan ->\omit                    \@multispan l.8 \tableheadline[2]{C}   I also get the error when I do not even use the optional argument (see commented line in the MWE). Any ideas what I am doing wrong?


The description of the Warp Drive in Star Trek:  Warp drive was a technology that allowed space travel at faster-than-light speeds. It worked by generating warp fields to form a subspace bubble that enveloped the starship, distorting the local spacetime continuum and moving the starship at velocities that could greatly exceed the speed of light. From the , emphasis by me  Is it possible to create a subspace bubble and therefore basically entering Warp but standing still? And is it possible to fly backwards / sidewards in the Warp or are there technical restrictions preventing that? That would IMHO open some interesting tactical possibilities, specially the flying backwards. One could perform the "inverse Picard Maneuver" and therefore briefly vanish from the enemies sensor.

Most modern motorized vehicles are capable of both forward and reverse motion.  In the Star Trek universe, can an unmodified warp drive also be used to move backwards?  I realize that pretty much every ship we've seen has its navigational deflector (that is, the force field generator that pushes space dust and small debris away from the path of the ship) installed at the front of the vessel.  But ; it doesn't make it impossible.  Safety issues aside, is there any technical or engineering reason why warp drives cannot operate in reverse?  If not, have we ever observed a ship warping backwards, perhaps to escape from a dire emergency?  Or have we perhaps observed ships with an extra navigational deflector mounted on the rear?  I'm interested primarily in the canonical TNG-era continuity (including the DS9 and Voyager series), with preference given to evidence from the shows and movies themselves, or alternatively to reliable print sources such as the show's Writers'/Directors' Guide and the Technical Manual.  If this issue is absolutely never discussed in those sources, then an answer based on other Trek series/movies/continuities/canons would be acceptable.


Is my samsung galaxy note 8.0 (gt-5110) compatible with the new Ubuntu convergence tablet software, I would like to give it a spin :-)

With the announcement of the Ubuntu Phone OS I'd like to know what phone (and tablet) models are supported at this time.  Note from foss & Oli: We are making this the master question for all future "Will this work on <insert random tablet/phone/device here>?!" questions


Suppose that I'm using this function to implement logistic regression in MATLAB R2015a:  [coefs,~,stats] = glmfit(TrainInputs,TrainTargets,'binomial','logit'); % Logistic regression   I have ten continues inputs and a binary output (1 and 0). This is the coefs output of above function:  coefs =  2.04869088486007 -4.66230054501349 0.355690380077187 -1.87230109681715 6.85763253382301 3.46437006313075 -0.282766819896174 -1.08763387246821 -1.94250600133904 1.46621342829667 -2.83661766065114   What is meaning of the coefs in logistic regression of MATLAB? Suppose that input names are X1 to X10. If we have 1 % increase in X1, We have -4.66% increase in probability of being class 1?

This is somewhat of a beginner's question, but how does one interpret an exp(B) result of 6.012 in a multinomial logistic regression model?  1) is it 6.012-1.0 = 5.012 = 5012% increase in risk?  or  2) 6.012/(1+6.012) = 0.857 = 85.7% increase in risk?  In case both alternatives are incorrect, can someone please mention the correct way?  Ive searched many resources on the internet and I get to these two alternatives, and I am not entirely sure which one is correct.


I’m looking for a book about an agent who is a trained assasin. He is sent to four different planets to kill a target, but for each job his mind is put into a surrogate body before being sent planetside. One of the planets is a place called "Chavon" I think and in another of the books he is temporarily turned into a dinosaur-type creature through magic.  It’s a brilliant series and I would be interested if anyone can recall what it was called as I wish to get it as a birthday present for my sister.

I read a book once where an agent of a futuristic multi-planet government was sent on a mission, and in doing so, used a machine to impress copies of his mind on other people to send them. I remember no names, of people or locations, but I can describe what I do remember. The place the copies of this man were sent was a planetary system that was used as a prison. The planets were used as a prison because of a unique type of bacteria or virus that lived there. Whenever that bacteria would go too far from the planet, it'd die, and take any organism that it was inside with it. There were 4 planets in the system, and copies of this man were sent to each one. Each planet granted the copy one "power", unique to the planet, through the bacterium.  In one world the bacteria would break down everything man-made remarkably quick, but some people could control them enough to stop, and even create things for you. Another gave people the ability to swap minds during sleep, waaking up into a different body altogether. A third gave the man "adaptive DNA", so to speak. He subconsciously would change his DNA to match the environment, which could've meant a sex change, if he lived in an all-male environment. And sadly, I dont remember the 4th well at all. I just know someone became a dragon at some point, and that someone was blind.  Anyway, I read this book at my high school library. That copy was a plain brown cover, no title or anything, and although the name was inside, I have forgotten it. I have forgotten it and the author and  all the unique names to search for, and all my searching for the things in this description have yielded nothing. If anyone knows this book, please tell me its name, or anything that could lead to me finding this book again.


I want to take 2 iPhones with me (36000 INR each) to India from USA,as i stayed 4 month here and I am resident of INDIA and went US for official work. Will there be any problem or any amount do i need to pay to custom or any where else in US/INDIA airport?  I am already carrying my used Camera(40000 INR+Professional laptop) with me.  ITEMS carry  :: 1 Lpatop(offical)+DSLR camera(not from US ,already had of 40000 INR+ 2 new iPHONEs of 36000+36000 brought from US and carrying to india)  Note : I am travelling alone.  Regards, Anshuman Gaur

I am planning to travel to India (COK airport, Kerala) from United States. I want to take my laptop as well as my tablet (iPad). Am I allowed to take both in my backpack with my documents related my work. I think I am allowed to take only one computer as per the rule. Will the customs consider my iPad as a computer?  What all I can take?   One of my friends took 2 laptops (1 work and 1 personal) and had trouble at the airport.  Also I am planning to take some wristwatches (7 of them, each avg price is 45 $). I read in a website that I can take stuff up to max 35000 INR. Is that true? In that case, how will I manage my stuff?


Can someone explain me this  please I am a bit confused?  It's from a texbook I am reading (block cipher companion)  it says that:      each weak key has  $2^{32}$ fixed points $m$ where $\operatorname{DES}_w(m) = m$ ( $w$ is a DES weak key). In other words encrypting a fixed point gives exactly the same point. To see this consider the $2^{32}$ ciphertexts after 8 rounds of encryption for which the two 32 bit halves are equal. For a weak  DES key, the round keys of the eighth and ninth rounds are equal. Thus the intermediate texts after seven rounds and after nine rounds of encryption will be equal. Since the round keys of the 7th and the 10th rounds are equal, the intermediate texts after 6 rounds and after 10 rounds of encryption will be equal. Continuing like this it follows that the plaintext will be equal to the ciphertext.    Now did not quite get :   Why are there $2^{32}$ fixed points?  And why after the eighth round of encryption the two halves must be equal? What does the author mean by the intermediate texts exactly? And how are they being equal?   P.S.: This question is not asking for what the weak keys are. I am asking for "fixed points" not exactly weak keys. For this reason I think it is not a duplicate of any other question. There is one similar question to what I've asked for which I have checked and saw that no satisfactory answer has been given there either.  Here is the similar question with no proper answers:

A weak key for DES is a key $K$ such that $DES_{k_1}(DES_{k_2}(x))=x$ for all $x$.  I don't get why are the 4 keys $k_1||k_2$: $1^{112}$, $0^{112}$, $0^{56}||1^{56}$, $1^{56}||0^{56}$ considered as weak. (Also didn't find some detailed explanation in the web.)


Let $x$ be a vector in $\mathbb{R}^n$. Why is $\frac{x}{\| x \|}$ a unit vector, for $x\neq 0$?  If I try to simplify it, I get the following: $\frac{x}{\sqrt{x \cdot x}}$, and I'm not sure how to proceed.  So I'm looking for a proof or explanation as to why it is a unit vector.

Straightforward question, so if it is applied to every element of a vector that means that every one of them is scaled down exactly length times. How did people come up with this, to make it exactly 1? I am sorry if this is fairly obvious, but I just don't see it.


I would like to display customer reviews from another website (with their agreement) own my own site for certain product pages.   Using these 3rd party reviews would be helpful for users, though there's an issue with duplicate content as I'll be republishing these reviews from the other website.  I don't want to noindex the whole page as many of these product pages already rank well.  One option I'm considering is to place the review content in an iframe and then block the iframe's URL in the robots.txt, though I'm unclear as to whether this would be frowned upon by search engines.  Is there a best practice, recognized and accepted by Google, for noindexing or blocking crawling of certain sections of a page?

As a webmaster in charge of a tiny site that has a forum, I regularly receive complains from users that both the internal search engine and that external searches (like when using Google) are totally polluted by my users' signatures (they're using long signatures and that's part of the forum's experience because signatures makes a lot of sense in my forum).  So basically I'm seeing two options as of now:   Rendering the signature as a picture and when a user click on the "signature picture" it gets taken to a page that contains the real signature (with the links in the signature etc.) and that page is set as being non-crawlable by search engine spiders).  This would consume some bandwidth and need some work (because I'd need an HTML renderer producing the picture etc.) but obviously it would solve the issue (there are tiny gotchas in that the signature wouldn't respect the font/color scheme of the users but my users are very creative with their signatures anyway, using custom fonts/colors/size etc. so it's not that much of an issue). Marking every part of the webpage that contains a signature as being non-crawlable.   However I'm not sure about the later: is this something that can be done?  Can you just mark specific parts of a webpage as being non-crawlable?


My partner is pregnant with my child. We were doing homework on the couch with her twelve year old daughter. All was going well when she started hitting her mother and then hit her mildly in the stomach.  I didn't react other than saying you shouldn't do that. I am concerned she might have hurt the fetus like that. The fetus is three and a half months old.  I am also concerned she might be doing that when I'm not there. My partner may not be saying anything to me to relieve the pressure.  Her daughter and son sometimes say they don't want this child we wanted.  What should I do, as a father?

I have a 2 year old son and another baby on the way. I just recently found out I'm pregnant but not sure how far just yet. My son rammed into my stomach like he is always doing but this time it made me start having small pains in my stomach. I rushed to the bathroom to make sure there wasn't any bleeding.  I'm concerned his rough play could hurt the fetus if it continues. How should I put a stop to it?


\usepackage{lscape}  \usepackage{afterpage}% removing blank space before landscape \usepackage{adjustbox} \usepackage{graphicx}   these are the packages i am using for the below figure    \afterpage{     \begin{landscape}         \begin{figure}\label{fig:604}             \centering             \begin{adjustbox}{addcode={\begin{minipage}{\width}}{\caption{Comparison of Velocity ratio FEM,Experiment and Analytical}\end{minipage}},rotate=180,center}                 %\includestandalone[angle=90,width=\linewidth]{Velocity_ratio_comparison}                 \includegraphics[width=0.8\linewidth]{image001.png}                 %\caption{My caption}             \end{adjustbox}              \end{figure}     \end{landscape} }

\documentclass{article} \usepackage{algorithm}  \begin{document} \setcounter{section}{54} \section{A section with no label} \begin{algorithm} \label{myalg} \caption{An algorithm with the label `myalg'.} \end{algorithm} Reference to myalg: \ref{myalg}. \end{document}   With this code, the reference givens 55 (the section number); if I move the label after the caption command, I get the correct reference (1).  Why should this be the case? I find it confusing: when thinking about an algorithm as an environment, you expect to be able to label it right after you began it. At the very least I would expect some kind of error or "??" to appear, rather than the previous environment or reference-able entity being used.


/home encryption   I still want to protect my data, and the workaround is to encrypt the whole partition.  How do I encrypt a whole partition mounted at / in Ubuntu 18.04?

At what point during the installation of Ubuntu 18.04 do I get the option to encrypt my disk?  Somehow I missed it, so if I'll need to start over I'd like to know where to look.  Alternatively, what is a good way to encrypt after installation? I was looking at  but the link to  is broken.  Update: I had also started looking into alternatives to encrypt home folder only but I'll follow the discussion from  for that.


I remember watching an animated movie (part of, because it was incomplete) on a videotape in the 90's. It was a full-length movie, not likely a series. Please help to identify.   The movie was French (with English subtitles) The protagonist is a little boy lost on a jungle planet. His parents have perished before. A rag-tag rescue team travels in a spaceship to save him. The team includes a captain, some rogue prince and an old balding man with a patch on his head (and some other people I do not remember) The boy communicates with the team using an odd, egg-shape 2-way transmitter. The old man knows the planet where the boy is stranded pretty well The team lands on some planet which is populated with faceless people. They try to subvert the team, but the Rogue Prince rebels and the power of the faceless people is disrupted, giving the team a chance to fly away. The boy makes friends with some elephantine local creature.   Then the tape ended. It did not include any title or opening credits either, as someone tried to jam in as many films on the tape as possible.

A guy on a space ship picks up a distress call, a boy is stranded on a planet with a hostile environment. He & his crew go to the rescue, stopping on the way to pick up an old man who comes with them. Most of the top of the old guy's skull is metal, from an old injury.  They've various adventures on the way (their ship is boarded by pirates/bandits/hostile forces at one point).  They get to the planet with the boy. They've limited time to save him as the planet is being moved back in time. (I can't remember why) When they find the boy, he's being attacked by giant wasp-type-things.   The boy is injured on the top of his head. The old guy dies protecting him. The boy gets shifted back in time with the planet and - you guessed it - survives, grows up and turns out to be the old guy.  Now that I've remembered some of it, the bits I can't remember are driving me crazy. I'd love to see this again, if I could identify it I might be able to track down a copy.  I'd swear I saw this mid 80's on morning TV, but it I could be out by 5 years either way. Thanks


I have a Dictionary<String, Object> with some data in it.  I want to loop through each element, I know I can use foreach for that. But I little bit concerned about the performance and the memory usage for it.  But here's the thing, we know that for (;;) is faster and use less RAM ( if I remember correctly ) than foreach () since it doesn't create new instance for each element.  But we can't use for (;;) directly to iterate through it, so we need LINQ's ElementAt() or something similar for it.  So which is more efficient, is using foreach () more efficient   private Dictionary <String, Object> items; foreach (var entry in items) {   // do something with entry }   or using for (;;) combined with LINQ is more efficient  private Dictionary <String, Object> items; for (var c = 0; c < items.Count; c++) {   // do something with items.ElementAt(c) }   or for (;;) combined with LINQ is the same as foreach () because items.ElementAt() may also create instance ?  EDIT : If there's discussion discussing about it and maybe has the answer, feel free to mark this as duplicate, but let me know the reference.

In C#/VB.NET/.NET, which loop runs faster, for or foreach?  Ever since I read that a for loop works faster than a foreach loop a  I assumed it stood true for all collections, generic collections, all arrays, etc.  I scoured Google and found a few articles, but most of them are inconclusive (read comments on the articles) and open ended.  What would be ideal is to have each scenario listed and the best solution for the same.  For example (just an example of how it should be):   for iterating an array of 1000+ strings - for is better than foreach for iterating over IList (non generic) strings - foreach is better than for   A few references found on the web for the same:               [Edit]  Apart from the readability aspect of it, I am really interested in facts and figures. There are applications where the last mile of performance optimization squeezed do matter.


Why does $987,654,321$ divided by $123,456,789 = 8$?   Is it a coincidence or is there a special reason?  Note: The numbers are a mirror of each other

Many years ago,  I noticed that $987654321/123456789 = 8.0000000729\ldots$.  I sent it in to Martin Gardner at Scientific American and he published it in his column!!!  My life has gone downhill since then:)  My questions are:   Why is this so? What happens beyond the "$729$"? What happens in bases other than $10$?


Definition If $V$ is a finite dimensional vector space then we say that the norm $||\cdot||_1$ and $||\cdot||_2$ are equivalent if and only if there exist two positive constant $m$ and $M$ such that $$ m||v||_1\le||v||_2\le M||v||_2 $$ for any $v\in V$. Lemma If $V$ is a finite dimensional vector space then the function $||\cdot||_\infty:V\rightarrow\Bbb R^+_0$ defined through the condition $$ ||v||_\infty:=\max_{i=1,...,n}|v_i| $$ is a norm in $V$. Theorem If $V$ is a finite dimensional vector space then all norm in $V$ are equivalent.  Clearly if $||\cdot||$ is a norm in $V$ then by triangle inequality $$ ||v||\le M\cdot||v||_\infty $$ where $M:=\max_{i=1,...,n}||e_i||$ for any basis $\mathcal{B}:=\{e_1,...,e_n\}$. Unfortunately I can't prove the other inequality. So could someone help me, please?

I want to prove the following theorem (no idea whether it has a name):  Let $V = \mathbb{R}^n$ or $\mathbb{C}^n$ and $\|\cdot\|$ be a norm on $V$. Then, there exist $C_1, C_2 > 0$ such that for all $x \in V$:  $$C_1 \|x\|_\infty \leq \|x\| \leq C_2 \|x\|_\infty$$  I first let $x \neq 0$ (otherwise it would be trivial). Then, I divided by $\|x\|_\infty$ and normalized the vector $x$ such that $\|x\|_\infty = 1$. That left me with  $$C_1 \leq \|x\| \leq C_2$$  but I don't see how this could help me or how I could possibly limit an unknown norm. How can I proceed? Or is this the wrong way anyway? Thanks for any answers.


I have been running Apple Mail for years (too many to count) and I have never had a situation where messages won't un-flag. But currently I have about 12 messages that are stuck in "Flagged" state. They reside in various folders in Mail, but they always show up in the Flagged folder. I have tried flagging them with different flag color and unflagging them but after about a second or two they the number in the flagged folder bounces back up. When I select them and "clear flag" no flag appears on them but they stay in the flagged folder.  Any clues on how to permanently remove the flag from these message?

I've had this problem before and can't recall how I managed to fix it last time. I use Apple Mail to access my Gmail and normally flagged emails show up correctly. Starred emails in Gmail equate to flagged emails in Apple Mail and I can unflag an email in either Gmail or Apple Mail and it works.  But now I've got four emails that I can't unflag. They're not flagged in Gmail at all (although they used to be). When I see them in the Flagged folder in Apple Mail, they don't even have flag icons next to them but they're still counted in the number showing next to "Flagged". If I manually re-flag them and then unflag them, they disappear from the Flagged box. But then if I click into Inbox and then back into Flagged they show up again.  Any ideas about how to make these guys disappear for good?!


I want to work with frost and several metrics  First, I want to map the number of nights that have temperatures below 0 in a year. This code seems to do this.  Second, I want to calculate the number of days between the first and last night with temperatures below zero.  How can I get the frequency of frost for the month of October since 2002 or better still in a decidical way? Sum of values below 0 ° C divided amount of values without clouds.  Code:

I want to do two things.   First, I want to map the number of nights that have temperatures below 0 in one year. This code seems to do this.   Second, I want to calculate the number of days between the first and last nights with sub-zero temps. I managed to get the first one in the series but the output is a format I don't know: 994118400000.   How can I get the last night the series and measure the span of time between the first and last dates in the series?  var NightSA = ee.ImageCollection('MODIS/006/MOD11A1').select('LST_Night_1km');  var count2001 = NightSA.filterDate('2001-07-01','2002-06-30').map(function(NightSA) {return NightSA.lt(0).set('system:time_start', NightSA.get('system:time_start'))});  var first2001 = count2001.first().get('system:time_start'); print (first2001);   var nightSurfaceTempVis = {   min: 0,   max: 365,   palette: [     '040274', '040281', '0502a3', '0502b8', '0502ce', '0502e6',     '0602ff', '235cb1', '307ef3', '269db1', '30c8e2', '32d3ef',     '3be285', '3ff38f', '86e26f', '3ae237', 'b5e22e', 'd6e21f',     'fff705', 'ffd611', 'ffb613', 'ff8b13', 'ff6e08', 'ff500d',     'ff0000', 'de0101', 'c21301', 'a71001', '911003'   ], };  Map.addLayer(count2001.count(),nightSurfaceTempVis,'Nights < 0');


I'm rendering local JSON to the browser and each item contains a modified date in ISO 8601 time (such as "2019-03-19T18:50:39Z"). The plan is to make it so that if the Created date is older than 30 days then it will be hidden from the div.  Should I convert the time into a more readable format (such as 03/19/2019)? Would it be easier to work with?  New JSON data could be added at any point, which is why I need to have my code be dynamic. It's part of the reason why I'm struggling with this one.  JS snippet:  import testjson from './test.json';  export default class {     constructor() {      }      loadNewCourses() {         let newCrs = testjson.d.results             .sort(function(a, b) { // sorts by newest                 return (a.Created < b.Created) ? 1 : ((b.Created  { // no duplicates                 return (idx === self.map(el => el.Category).indexOf(el.Category))             })             .map(x => {                 return {                     "Category": x.Category,                     "Title": x.Title,                     "Description": x.Description,                     "Created": x.Created                 }             })    $.each(newCrs, function(idx, val) { // ---- does this look right?         let current = new Date();         let expiry = new Date(val.Created)          if (current.getTime() > expiry.getTime()) {             $('.categoryName').hide();         } else if (current.getTime() < expiry.getTime()) {             $('.categoryName').show();         }     })          let curIndex = 0;         $.each(newCrs, function(idx, val) {             curIndex++; // this line must be here             let targetDiv = $("div.new-training-div > div[col='" + curIndex + "']");              let modalTrigger = $('
', {                 'class': 'categoryName',                 'data-category': val.Category,                 'data-target': '#modal-id',                 'data-toggle': 'modal',                 'text': val.Category             });              modalTrigger.prepend("&blacktriangleright;");              targetDiv.append(modalTrigger);              if(curIndex == 4) {                 curIndex = 0;             }          })      } // ------------------ loadNewCourses  }   JSON snippet:  },         "FileSystemObjectType": 0,         "Id": 80,         "Title": "Rome",         "Category": "WorldCapitals",         "Description": "A capital city (or simply capital) is the municipality exercising primary status in a country, state, province, or other administrative region, usually as its seat of government.",         "TopTrainingCourse": false,         "VideoLink": "https:\/\/www.google.com",         "ID": 80,         "Modified": "2019-03-19T18:50:39Z",         "Created": "2019-03-19T18:50:39Z"        } ...etc

How do I get the number of days between two dates in JavaScript? For example, given two dates in input boxes:  <input id="first" value="1/1/2000"/> <input id="second" value="1/1/2001"/>  <script>   alert(datediff("day", first, second)); // what goes here? </script>


I have a Python class that takes an arguments to set the state of an object. This argument must be one option in a list of available options; for example, a traffic light can either be red, green or orange.   I have two approaches to handle this problem. I can use a string to set the state, but then I'll have to do additional error checking and it is unclear without looking at the code what states are available. Alternatively I can create a class that acts as an enum.   Which of these methods (or what other method) should I use?  Example with strings:  class Light(object):      def __init__(self, color):         self.color = color      def turn_on(self):         if self.color == 'red':             self.turn_on_red_light()         if self.color == 'green':             self.turn_on_green_light()         if self.color == 'orange':             self.turn_on_orange_light()      def turn_on_red_light():         # do stuff         return      def turn_on_green_light():         # do stuff         return      def turn_on_orange_light():         # do stuff         return  light = Light('red') light.turn_on()   Alternative using simple "enum":  class Colors(object):     red, green, orange = range(3)  class Light(object):     def __init__(self, color):         self.color = color      def turn_on(self):         if self.color == Colors.red:             self.turn_on_red_light()  # as above         if self.color == Colors.green:             self.turn_on_green_light()  # as above         if self.color == Colors.orange:             self.turn_on_orange_light()  # as above  light = Light(Colors.red) light.turn_on()   Maybe this is not the best example as you can just call light.turn_on_red_light(), but then that logic to decide what function to call must sit somewhere else. Let's pretend that is not an option.  I come across this situation often. Frequently I use it to define 'settings' within the class. I'd be interested to know what is the preferred method in Python or any other ways it can be improved?

I'm mainly a C# developer, but I'm currently working on a project in Python.  How can I represent the equivalent of an Enum in Python?


How can I disable the app notifications of a certain app I installed from Google Play?

On my iphone, there is a "notifications" setting section, which basically just allows me to choose which apps has the power to notify me.  I was wondering if there's anything similar that is available on the Samsung Galaxy s2?  Basically, we have a new app called Scramble For Friends. And it keeps notifying us every time someone has finished their turn so that I can play. We play random people so this could be in the middle of the night or in a meeting etc.  It just vibrates but still - it's annoying and we want to turn it off. We also don't want to turn off other notifications like Email, Facebook etc. - we just want to turn off the notifications for Scramble For Friends.  I've been looking around in the Settings but there doesn't seem to be a universal page which deals just with notifications.


This is a probably a stupid question, but I can't figure it out myself.   I think that they are not, but I can't prove it formally. One reason that they are probably not isomorphic is that $x^2-2x-1 \in \mathbb{Q}[x] \subset \mathbb{Q}[\sqrt2][x]$ has no roots in $\mathbb{Q}$, but it has its roots in $\mathbb{Q}[\sqrt2]$.   I am not sure whether or not my argument is valid. Any hint/suggestion would be appreciated.

In this  we saw isomorphism of vector spaces over $\mathbb{Q}$. Just came across this question:   Is $\mathbb{Q}(\sqrt{2}) \cong \mathbb{Q}(\sqrt{3})$?   I know these as $\mathbb{Q}$-Vector spaces, are isomorphic from the  linked post. But as fields are they isomorphic? I neither know how to prove it nor how to disprove it.


Do we have a fast method for proving that the equation $x^2+y^2=0$ over $\mathbb{F}_{7}$ has one solution $(0,0)$ without testing all the elements of $\mathbb{F}_{7}$?

Let $x$ and $y$ be integers not congruent to $0$ modulo $p$ where $p$ is a prime. Prove that if $p \equiv 3 \pmod{4}$ then $x^2+y^2 \not \equiv 0 \pmod{p}$.   I thought about proving this algebraically and by contradiction. So we say $x^2+y^2 = pz$ and have to show this is impossible.


I have an android device which i want to use to provide internet to a group of people. I want to leave the wifi open but a user must acquire a username and a password to properly login to our internet.  Once a user is connected to our wifi,i want the user to be redirected to our login page. Is there an android hotspot app that can enable me to redirect a user to a custom page?.

Some Wi-Fi networks such as those you find on coffee shops, when connected to, automatically redirect you to a web page where you will need to do something (enter credentials, accept terms of service, etc) in order to access the internet. Is the same possible with an android hotspot?


I have a ton of video files that were downloaded from the internet. Most are ok, but some were not completely downloaded. Is there a program that will tell me if a video file is complete?  Either a command line program or something that can verify all videos in a directory structure.

This title could be somewhat misleading, so let me explain ...  I'm downloading a video file ... mpeg, avi - being one of the popular formats. Now, if I am downloading it, and the download breaks in the middle of the uhm ... download, then, for example, Windows Media Player will give out some error and refuse to play it (although the file is, let's say, 98% complete). But, players like KMPlayer, or MediaPlayer Classic will play it up until that point (as the matter of fact, they can play it while it is being downloaded as well).  So, I'm interested, ... without using any means of download (download managers and alike) to secure the file is completely downloaded, how can one verify whether the video file is downloaded whole, and that it is complete ?


I have already made a JList below a JTextField. It shows the information that I want coming from MySQL database. But when I choose from the list and gets the item to be on the text field, and then type backspace in gives me java.lang.NullPointerException. So I'll just click okay to remove the error dialog box. But then when I type something again on the text field, it repeats the same error. I don't know how to fix it. I think it can be fixed with some key events or mouse events. But I don't know how to do it. Can someone give me an example of what to code in KeyEvent to stop the error? Or any suggestion will do.

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


I finished my 3rd year at a US public research university; however, since I switched majors 2.5 years into my studies (engineering to physics), I still have 2 more years to go. Because of this, I will only have the core undergrad classes under my belt (classical, stat., and quantum mech., as well as E&M with some relativistic treatments).  I would like to apply to high energy theory groups, but I get the impression that successful applicants all have had multiple years of graduate coursework in physics and mathematics at their undergrad institutions. Of course, I understand that research experience is far more important (and I think I do well in that aspect), but there's no doubt that the other highly qualified applicants have stellar research experiences as well -- with work in topics relevant to hep-th, no less.  My question, then, is whether this impression is realistic, or if I'm totally off-base and misguided here. My biggest concern is that, from what I have been told, a PhD in HET is not worth it unless it comes from one of the top 10 programs (due to the scarcity of positions and lack of funding afterwards). Again, this may be a total misconception on my part, but the prospects do seem rough (more so than other academic positions, I should say).  P.S.: FWIW, my interest in HET and cosmology grew from going through Anthony Zee's books on QFT and gravity (having self-studied the prereqs through a mix of Shankar and Griffiths), so I believe I have some idea of the actual nature/mathematics of the topics. However, I'm sure that saying something along these lines in my application, or how I go through the arXiv looking for papers I don't understand, is nothing short of pettiness. It would certainly be strange for someone with no formal experience in the subjects to profess deep interests in doing research in said field.

When applying to a PhD program in the US, how does the admissions process work? If an applicant is weak in a particular area, is it possible to offset that by being strong in a different area?  Note that this question originated from this . Please feel free to edit the question to improve it.


To my understanding, the following code should print true in both cases, since values are some not changed.  However, when I run the following code it is printing true and false:     public class Test {     public static void main(String[] args) {         HashMap<String, Boolean> map1 = new HashMap<String, Boolean>();         HashMap<String, Boolean> map2 = new HashMap<String, Boolean>();          map1.put("true", Boolean.TRUE);         map1.put("false", Boolean.FALSE);          map2.put("true", Boolean.TRUE);         map2.put("false", Boolean.FALSE);          System.out.println(map1.equals(map2)); // prints true as expected          // prints false even though the values are indeed equal:         System.out.println(map1.values().equals(map2.values()));     }  }   Can some one help me understand why it is printing false in second case.

Did you know that :  Map<Object,Object> m1 = new HashMap<Object, Object>(); Map<Object,Object> m2 = new HashMap<Object, Object>(); System.out.println("m1.equals(m2) = "+m1.equals(m2)); System.out.println("m1.keySet().equals(m2.keySet()) = "             +m1.keySet().equals(m2.keySet())); System.out.println("m1.entrySet().equals(m2.entrySet()) = "             +m1.entrySet().equals(m2.entrySet())); System.out.println("m1.values().equals(m2.values()) = "             +m1.values().equals(m2.values()));   would output :  m1.equals(m2) = true m1.keySet().equals(m2.keySet()) = true m1.entrySet().equals(m2.entrySet()) = true m1.values().equals(m2.values()) = false   This is caused by the fact that AbstractCollection (which HashMap$Values inherits from) does not overrides #equals().  Do you have an idea why this is so ?


Coxeter and Greitzer, in their excellent Geometry Revisited, list a few "hardy perennials" in elementary geometry: tough problems solvable by elementary methods. Their problem number 4 (on page 26 in my edition) is as follows:     Let $ABC$ be an isosceles triangle with equal angles $80^\circ$ at $B$   and $C$. Segments $BD$ and $CE$, extended to the opposite sides of the   triangle, divide $\angle B$ and $\angle C$ into $60^\circ$/$20^\circ$   and $30^\circ$/$50^\circ$, respectively. (See figure below.) What is   the measure of $\angle EDB$?      poses a similar problem, and calls it the "world's hardest easy geometry problem." In this problem, the $80^\circ$ angles are divided as $60^\circ$/$20^\circ$ and $70^\circ$/$10^\circ$.  Both of these problems are difficult and quite satisfying. (I will not give the answer here so as not to deprive casual searchers of the pleasure of solving them themselves; solutions to both can be easily found online.) I have also solved the related problem where the two $80^\circ$ angles are split as $70^\circ$/$10^\circ$ and $50^\circ$/$30^\circ$.  I have two questions:   My solutions to all three problems have a similar flavor, but they're quite different. Is there a unifying insight or more sophisticated perspective that provides the solution to all three? All three problems are very pleasantly challenging, despite their apparent simplicity. What accounts for their difficulty? Is there a unifying insight that shows why precisely they are both difficult and solvable by elementary means?

The following is a geometry puzzle from a math school book. Even though it has been a long time since I finished school, I remember this puzzle quite well, and I don't have a nice solution to it.  So here is the puzzle:    The triangle $ABC$ is known to be isosceles, that is, $AC=BC$. The labelled angles are known to be $\alpha=\gamma=20°$, $\beta=30°$. The task is to find the angle labelled "?".  The only solution that I know of is to use the sine formula and cosine formula several times. From this one can obtain a numerical solution. Moreover this number can be algebraically shown to be correct (all sines and cosines are contained in the real subfield of the 36th cyclotomic field). So in this sense I solved the problem, but the solution is kind of a brute force attack (for example, some of the polynomials that show up in the computation have coefficients > 1000000). Since the puzzle originates from a book that deals only with elemetary geometry (and not even trigonometry if I remember correctly) there has to be a more elegant solution.


I'm doing a project which generates 10 to 20 similar images, which I should implement in a report. Since they are all "generic" I would like to have an algorithm which autogenerates the image, caption and label, according to the image name. The following code is already implemented and partly operational. The issue is that the compiler generates all the images I need, as well as giving them the correct caption, but it fails at giving them a label, which I would find usefull when commenting each picture. I get a couple of warnings regarding labels without links, and several undefined references, so maybe there is some issue in the compile order.  Is there any easy fix to this? I'm fairly new at Latex, would appreciate any help given =)  The code I'm using today is given below:      \foreach \i in {1000,2000,3000,4000,5000,6000,7000,8000,9000,10000,11000,12000} { \lipsum [\i]   \begin{figure}[htb]     \centering    \includegraphics[width=0.8\textwidth]{Figures/Results/res_\i K.PNG}    \label{fig:res_\i}    \caption[Color temperature measurement \i K]{Color temperature measurement \i K}   %    \label{fig:res_\i}  \end{figure}  }  As \autoref{fig:res_1000} depicts

\documentclass{article} \usepackage{algorithm}  \begin{document} \setcounter{section}{54} \section{A section with no label} \begin{algorithm} \label{myalg} \caption{An algorithm with the label `myalg'.} \end{algorithm} Reference to myalg: \ref{myalg}. \end{document}   With this code, the reference givens 55 (the section number); if I move the label after the caption command, I get the correct reference (1).  Why should this be the case? I find it confusing: when thinking about an algorithm as an environment, you expect to be able to label it right after you began it. At the very least I would expect some kind of error or "??" to appear, rather than the previous environment or reference-able entity being used.


I'm looking for a program that (tries to) makes a complete ISD-image of a damaged DVD or CD.  This is (AFAIK) done by reading the damged media time and time again, until the program is able to put together an undaged ISO-image of the whole disk.  I just can't remember what it was called or where I found it...

I usually use the very nice and simple dvdbackup program to rip and backup my .   However some of my DVDs have a few scratches and my DVD drive has some trouble reading a few sectors. So, is there a tool similar to cdparanoia, but for DVDs?


I have some address points selected for which that I want to update the address field based upon the row in the selection. How do I figure out the name of the selection taable to pass to arcpy.UpdateCursor()?

I have a question regarding selections in ArcGIS for Desktop. Assumed I have one layer in ArcMap and I have selected two of five features.   Is it possible to get a list of all selected features by using Python?   It would be fine if there is a way to get one special (or all) attribute(s) of the selected features stored in a list that can be written into a txt file.  Is it possible to do this in ArcGIS for Desktop?


I have been trying to solve the following problem, but I am getting stuck...  we have: $-y^2dx + x^2dy = 0$   given: $u(x,y) = \frac{1}{(x-y)^2}$  both have partial derivative: $\frac{-2xy}{(x-y)^3}$  so we have the exact equation: $\frac{-y^2}{(x-y)^2}dx + \frac{x^2}{(x-y)^2}dy = 0$  now, I try integrate the dx expression: $\int\frac{-y^2}{(x-y)^2}dx$  This gives me: $\frac{y^2}{(x-y)} + g(y)$  Differentiating with respect to y gives: $\frac{-y(y-2x)}{(y-x)^2} +g'(y)$   I have checked my work for the above integral and derivative and also used an online calculator to verify that they are correct. Every other problem of this type that I have tried has had something meaningful come of:  $\frac{-y(y-2x)}{(y-x)^2} +g'(y) = \frac{x^2}{(x-y)^2}$  However, I have not been able to get anywhere using this to try to find a value for $g(y)$

I was doing some practice problems that my professor had sent us and I have not been able to figure out one of them. The given equation is:  $-y^2dx +x^2dy = 0$  He then asks us to verify that:  $ u(x, y) = \frac{1}{(x-y)^2}$  is an integrating factor.   I multiplied through to get:  $\frac{-y^2}{(x-y)^2}dx + \frac{x^2}{(x-y)^2}dy = 0$   However, the partial derivatives of these do not equal each other so I am a bit confused...


I tried to play sound today, and no sound.  Similar questions and my failed attempts:    but no solution here pulseaudio -k && sudo alsa force-reload changed nothing pacmd list-cards lists 0 cards.   also, typing pacmd set-card-profile 0 output:analog-stereo gives No card found by this name or index.  source:    Trying sudo alsactl init 0   gives  alsactl: init:1778: Cannot find soundcard '0'...  source:    mv ~/.config/pulse ~/.config/old_pulse and then rebooting also fails source:  sudo apt-get remove alsa-base pulseaudio sudo apt-get install alsa-base pulseaudio   failed.  Source:   6.  sudo apt-get --purge remove linux-sound-base alsa-base alsa-utils  sudo apt-get install linux-sound-base alsa-base alsa-utils  sudo apt-get install dkms build-essential linux-headers-`uname -r`  alsa-base alsa-firmware-loaders alsa-oss alsa-source alsa-tools  alsa-tools-gui alsa-utils alsamixergui  sudo usermod -a -G audio username  sudo reboot   failed, source:

I've been using Ubuntu 18.04 on my Thinkpad X1 Carbon 7th gen for some time now with the audio working just fine, but after running some updates yesterday it seems like the audio card has stopped working when I rebooted this morning, could this be related to each other?  dmsg output:  [   32.624585] skl_hda_dsp_generic skl_hda_dsp_generic: Unsupported HDAudio/iDisp configuration found [   32.624590] skl_hda_dsp_generic: probe of skl_hda_dsp_generic failed with error -22   output from /var/log/apt/history.log:  Start-Date: 2020-03-17  09:30:06 Commandline: aptdaemon role='role-commit-packages' sender=':1.214' Install: linux-image-5.3.0-42-generic:amd64 (5.3.0-42.34~18.04.1, automatic), linux-headers-5.3.0-42-generic:amd64 (5.3.0-42.34~18.04.1, automatic), linux-modules-extra-5.3.0-42-generic:amd64 (5.3.0-42.34~18.04.1, automatic), linux-headers-5.3.0-42:amd64 (5.3.0-42.34~18.04.1, automatic), linux-modules-5.3.0-42-generic:amd64 (5.3.0-42.34~18.04.1, automatic) Upgrade: gir1.2-nm-1.0:amd64 (1.10.6-2ubuntu1.2, 1.10.6-2ubuntu1.4), linux-libc-dev:amd64 (4.15.0-88.88, 4.15.0-91.92), linux-headers-generic-hwe-18.04:amd64 (5.3.0.40.97, 5.3.0.42.99), libnm0:amd64 (1.10.6-2ubuntu1.2, 1.10.6-2ubuntu1.4), network-manager:amd64 (1.10.6-2ubuntu1.2, 1.10.6-2ubuntu1.4), linux-image-generic-hwe-18.04:amd64 (5.3.0.40.97, 5.3.0.42.99), linux-signed-generic-hwe-18.04:amd64 (5.3.0.40.97, 5.3.0.42.99), linux-generic-hwe-18.04:amd64 (5.3.0.40.97, 5.3.0.42.99), network-manager-config-connectivity-ubuntu:amd64 (1.10.6-2ubuntu1.2, 1.10.6-2ubuntu1.4), code:amd64 (1.42.1-1581432938, 1.43.0-1583783132), linux-firmware:amd64 (1.173.15, 1.173.16), docker-ce:amd64 (5:19.03.7~3-0~ubuntu-bionic, 5:19.03.8~3-0~ubuntu-bionic), docker-ce-cli:amd64 (5:19.03.7~3-0~ubuntu-bionic, 5:19.03.8~3-0~ubuntu-bionic) End-Date: 2020-03-17  09:31:51  Start-Date: 2020-03-18  06:58:27 Commandline: /usr/bin/unattended-upgrade Remove: linux-headers-5.3.0-28:amd64 (5.3.0-28.30~18.04.1), linux-headers-5.3.0-28-generic:amd64 (5.3.0-28.30~18.04.1) End-Date: 2020-03-18  06:58:27  Start-Date: 2020-03-18  06:58:30 Commandline: /usr/bin/unattended-upgrade Remove: linux-modules-extra-5.3.0-28-generic:amd64 (5.3.0-28.30~18.04.1) End-Date: 2020-03-18  06:58:31  Start-Date: 2020-03-18  06:58:36 Commandline: /usr/bin/unattended-upgrade Remove: linux-modules-5.3.0-28-generic:amd64 (5.3.0-28.30~18.04.1), linux-image-5.3.0-28-generic:amd64 (5.3.0-28.30~18.04.1) End-Date: 2020-03-18  06:58:40  Start-Date: 2020-03-18  06:58:48 Commandline: /usr/bin/unattended-upgrade Upgrade: libcephfs2:amd64 (12.2.12-0ubuntu0.18.04.4, 12.2.12-0ubuntu0.18.04.5) End-Date: 2020-03-18  06:58:49  Start-Date: 2020-03-18  06:58:53 Commandline: /usr/bin/unattended-upgrade Upgrade: libicu60:amd64 (60.2-3ubuntu3, 60.2-3ubuntu3.1) End-Date: 2020-03-18  06:58:55  Start-Date: 2020-03-18  06:59:01 Commandline: /usr/bin/unattended-upgrade Upgrade: librados2:amd64 (12.2.12-0ubuntu0.18.04.4, 12.2.12-0ubuntu0.18.04.5) End-Date: 2020-03-18  06:59:02  Start-Date: 2020-03-18  06:59:08 Commandline: /usr/bin/unattended-upgrade Upgrade: python3-apport:amd64 (2.20.9-0ubuntu7.11, 2.20.9-0ubuntu7.12) End-Date: 2020-03-18  06:59:09  Start-Date: 2020-03-18  06:59:14 Commandline: /usr/bin/unattended-upgrade Upgrade: python3-problem-report:amd64 (2.20.9-0ubuntu7.11, 2.20.9-0ubuntu7.12) End-Date: 2020-03-18  06:59:15  Start-Date: 2020-03-18  06:59:18 Commandline: /usr/bin/unattended-upgrade Upgrade: apport:amd64 (2.20.9-0ubuntu7.11, 2.20.9-0ubuntu7.12) End-Date: 2020-03-18  06:59:21  Start-Date: 2020-03-18  06:59:24 Commandline: /usr/bin/unattended-upgrade Upgrade: apport-gtk:amd64 (2.20.9-0ubuntu7.11, 2.20.9-0ubuntu7.12) End-Date: 2020-03-18  06:59:25


Using notation $F_1 = 1, F_2 = 1, F_3 = 2, F_4 = 3, F_5 = 5, ...$ for Fibonacci numbers prove that for any positive integer $n$: $$\frac{1}{1\cdot 2} + \frac{2}{1\cdot 3} + \frac{3}{2 \cdot 5} + · · · + \frac{F_n}{F_{n-1}\cdot F_{n+1}} < 2$$ I attempted to use induction on this problem, but could not finish the proof. Are there any alternative methods or tips to help prove this? Any help greatly appreciated.

1) Let $F_1 = 1$, $F_2 = 1$, and $F_n = F_{n-1} + F_{n-2}$ for $n \geq 3$.   How do you prove that  $$\sum_{n=2}^\infty \frac1{F_{n-1} F_{n+1}} = 1$$   $$\sum_{n=2}^\infty \frac{F_n}{F_{n-1} F_{n+1}} = 1$$   Do you even use the formula $n(n+1)/2$?   I tried using $F_{n-1} = F_n - F_{n-2}$ and $F_{n+1} = F_n + F_{n-1}$ and then trying to figure out how to substitute those, but I've been going around in circles. How would you solve this? What tips can you give me to solve this? Is there any website that teaches this? I tried searching google and youtube but none were helpful.   2) Let $s_x = \tan(2/x)$. Where does this become nonincreasing? While using monotonic limits to establish there is a limit.   I was guessing you need to use upperbound and lowerbound but doesn't it go to infinity?


$$\sum_{k=1}^n k{n\choose k}=n\cdot 2^{n-1}$$  I have to prove the identity using a combinatorial proof: I think this should be my combinatorial proof.  We want to form a committee of $k$ people from a total of $n$ people.

Must show:     $\sum_{i=0}^n i{n \choose i} = n2^{n-1}$ using a combinatorial argument. I have tried picking the problem apart by determining that the summation is equal to 1/2 of the size of all subsets of a set of size n times n.  But I am having trouble relating that to what each term of the summation represents.


we can build array list of a..z range as the following   example1  list=({a..z}) echo $list echo ${list[*]} a b c d e f g h i j k l m n o p q r s t u v w x y z   but in case we want to set variable in the array as the follwing  var=a list=({$var..z}) echo ${list[*]} {a..z}   we not get the values from a..z as example1  How to set it so we can print all characters of the alphabet?

Can I use variables inside {} expansion without appealing to eval? If so, how?  This doesn't work:  $ touch 1.foo 1.bar $ ls 1.{foo,bar} 1.bar  1.foo $ extensions=foo,bar $ ls 1.{$extensions} ls: cannot access 1.{foo,bar}: No such file or directory   It works with eval:  $ eval ls 1.{$extensions} 1.bar  1.foo


What is the maximum amount of toothpaste an adult can safely use when brushing his or her teeth, and why? The person brushes his or her teeth and rinses out the mouth thoroughly after, once a day (just before bed). Edit after the question was closed as a duplicate: the duplicate question has answers that seem to clearly indicate that there any amount of toothpaste of toothpaste can be used by an adult when brushing his or her teeth, as long as the toothpaste is not swallowed but rather spat out after use.

Long story short: Is there a maximum number of teeth brushing per day without having fluoride poisoning?    Full story: It is certain that a high fluoride intake leads to .  This is related to ingestion only (that is swallowing toothpaste, drinking high-fluoride water, eating rich-fluoride food) of this element.  While, when we talk about fluoride in toothpastes, we have a completely different assumption and absorption . Thus, I assume, there will be different AI (adequate intake) and UL (upper intake level) than for fluoride food assumption.     my assumption is sustained by the fact that most commercial toothpastes have less than 1500 ppm of F− in them   Ultimately, does exist a daily upper safety level for fluorine absorbed from the toothpaste?


Downloaded ubuntu onto usb flash.  Changed boot order to usb on Dell.  Restart with flash drive in.  Reads flash then gives "no boot filename received" followed by "no operating system found."

I am looking at this:    I need to create a boot disk to test Ubuntu to make sure it will run on a PC (Compaq Mini CQ10-120LA) I was given. I can create the boot disk off of a Mac (in English) or Windows (but Windows is in Spanish and foreign to me).   Questions:     What format do I choose for the USB stick? (I wish the instructions stated this). What is Dash? (Will I know when I run the installer?) Can I do this from a Mac or Windows computer? Or only from Ubuntu?


In my next campaign I will be playing Druid. I didn't really understand how skill / saving throw proficiency works while wildshaped and other posts on the internet didn't help.     I will try to explain how I think it works and I would like to be corrected.  Example: Skill: Dexterity (Stealth) My Dexterity: +2 (15) Animal Dexterity: +1 (12) My Proficiency Bonus: +3 Animal Proficiency Bonus: +2     Modifier if I am proficient in stealth but the animal is not: 1 (Animal Dex) + 3 (My Proficiency Bonus) = 4 Modifier if the animal is proficient in stealth and I am not: 1 (Animal Dex) + 2 (Animal Proficiency Bonus) = 3 Modifier if both I and the animal are proficient in stealth: 1 (Animal Dex) + 3 (max. of 3 (My Proficiency Bonus) and 2 (Animal Proficiency Bonus)) = 4     Is this correct or did I understand the rules wrong?

When I Wild Shape, I take a beast's STR, DEX, and CON scores. I  and my INT, WIS, and CHA scores. I will focus this question on the assumption I'm proficient in Athletics, and I'm turning into a beast also proficient with Athletics.    I have +0 STR and +3 Proficiency, so +3 in Athletics Beast has +2 STR and a +4 bonus in Athletics   What is my Athletics bonus now?  On one hand, I keep my +3 proficiency bonus (so if I calculated things from scratch, I should have Athletics = +2 STR + 3 Prof = +5). On the other, tweets like  claim I should just use the beast's modifier, a +4, since it is higher than my Druid's +3.     A druid in beast form uses his or her proficiencies, except when the beast has the same proficiency with a higher bonus.   But in this case, I'm now a creature with +2 STR, +3 Prof, and a +4 in an Athletics skill I'm proficient with. Can anyone confirm if I do or do not recalculate proficiency bonuses when I Wild Shape (or Shapeshift)? The rules are not explicit, and the way I've interpreted them is that you take the new STR, DEX, CON scores, and recalculate modifiers for your skills. After this, if the Beast had a better bonus than you now have, you then take its bonus.    Similar , but it mostly refers to interactions with Expertise and other edge-cases. I'm looking for an (preferably backed-up by RAW or official comment) answer on whether I should recalculate my stats to accommodation my Proficiency Bonus with my new STR, DEX, or CON modifiers.  Also keep in mind, from this , it seems a reasonable opinion that we should recalculate bonuses when scores change. But if you don't recalculate any proficiencies, how would this be affected? You could be cursed to negative STR and keep a massive athletic bonus.


Useful threads are being closed as "not constructive:"     This question is not a good fit to our Q&A format. We expect answers to generally involve facts, references, or specific expertise; this question will likely solicit opinion, debate, arguments, polling, or extended discussion. See the .   For example,  was very useful for me since I am new to obfuscation and the question gave me a start. Also that question has lots of votes and bookmarks - these alone are the  markers of usefulness. The question is closed anyway. No idea why.  Same happened to my question, , which received one bookmark immediately.  I was waiting for an answer with the two products downloaded and installed.  I desired that experienced people would share their thoughts and point me to the better one. No. Closed. I.e. I must go to some other forum and ask there or I must search on Google and write down the pros and cons of each myself. I am not asking questions just because I have tons of time and want to chat; I need an answer, that's why I am asking. I am asking because I think that SO has the most professional people to answer and because I didn't find a good answer in Google.  I saw other questions closed which I myself found to be useful and I bookmarked some of the closed questions.  UPDATE  If I want people who have an experience which I do not have with some software products and I want to see which product is better in the terms of usability and reliability, not just better in terms of the price or has a better official website or better described on the official website, how do I ask this question? Or is this a question which I cannot ask on SO? I.e. this sort of information is not available on SO?  Is this one breaking the rules as well:  ?

I frequently come across a really useful answer on StackOverflow which has been closed because it doesn't match the Q&A format.  Examples include  ,  ,   ,  and there are others.  Where should this information be exchanged if it's not on stackoverflow?  It seems the moderators are often somewhat overzealous...  ---edit  When I say best, I mean they are informative and useful for someone who's looking for an answer to them.  Even if they do become a bit of a discussion, I value other people's opinions on the relative merits of the different JPA frameworks.  I come here looking to choose one and the answer helps me.  So what if it's not a definitive answer?  ---edit  I don't care how popular a question is, nor how interesting it is.  Users are interested in stuff that's useful to them.  Plenty of those were useful (as judged by the upvotes on the answers: 'This answer is useful'), but closed because they didn't have a definitive answer, as far as I can tell.  ---edit  Seems I'm not the first person to think this: there are various similar questions to mine like this one:   In it the user lists lots of other useful questions which have been closed:                    So isn't there a place on stackoverflow for these questions?  A discussion section, maybe?


In the first book, they make it clear he is the last Envoy. Everyone thinks they're all gone.      By the third book, they make it very clear the Protectorate can send Envoys if they want.    Did I miss something?

I have started watching Altered Carbon on Netflix. I have read the books long time ago. Why is Kovacs the last Envoy?


In the Wikipedia article about  one can find the following picture:   But shouldn't the E and B field be 90$^\circ$ out of phase? In the depicted way the energy isn't conserved. At 0 the energy is 0 and at $\frac{\pi}{2}$ the energy is maximal in both fields.

Here are some depictions of electromagnetic wave, similar to the depictions in other places:      Isn't there an error? It is logical to presume that the electric field should have maximum when magnetic field is at zero and vise versa, so that there is no moment when the both vectors are zero at the same time. Otherwise one comes to a conclusion that the total energy of the system becomes zero, then grows to maximum, then becomes zero again which contradicts the conservation law.


i heard that ubuntu is less ram hungry than windows, so downloaded the ubuntu iso file from   i followed every instruction such as using rufus for creating the boot usb.  but when i try to install ubuntu, i am getting several lines of errors like   how ever the solution to this was given in the same page below like:       (Add to the grub line: all_generic_ide pci=nommconf)       (Add to the kernel line: ide=nodma acpi=off) as i am new to installing linux i don't know how to edit those grub and kernel lines. i don't know where they are located  so please anyone help me. thank you

This question is asked often in Ask Ubuntu, sometimes with few hints about the situation.   Please provide a list of possible reasons to help troubleshoot the problem.


def combine(*bs):     c = {}     for b in bs:         for k, v in b.items():             c[k] = v + c.get(k, 0)     return c  What does *bs mean?

In the following method definitions, what does the * and ** do for param2?  def foo(param1, *param2): def bar(param1, **param2):


My question was closed on the English Language & Usage site.   Where do I go to argue why it should not have been closed? I heard there is a meta for that. Yet, I could not find it.

I'm trying to find the link to my site's meta site on the new top bar and I can't find it. In fact I can't find it anywhere on the page.  For example: electronics.meta.stackexchange.com.  Perhaps I'm just not very perceptive, or possibly this is an opportunity to improve the new design.


Do we have documented cases of animals purposely and consciously trying to end their own life? What leads to animal suicide, and is it preventable?  I've heard mixed answers from various biologists. Is anyone here capable of providing an answer?

Is there any documented evidence for suicide among vertebrates other than humans? Lemmings not accepted !


I am stuck at work, and i tried to install ios 8.4 to my iPhone 5s, now it's stuck on the "Connect to iTunes" screen, well I don't have a computer with iTunes on it. My laptop is my work computer and it's and ASUS, and I can't install iTunes on any of the desktops here because it's not allowed. I desperately need my phone for work right now. I've tried resetting it, locking it, everything.

I'm not really sure how, but after I woke up today, my phone was just displaying the loading spinner and doesn't start up anymore. It's weird because my phone turned off last night and suspecting that it was probably out of charge, I thought charging it overnight would fix the problem.   So, my iPhone is currently stuck on the iTunes/Apple Logo loop. When I put it into DFU/Recovery Mode and connect it to iTunes, it isn't able to restore it. It keeps throwing "Network Connection Problems" -- it downloads iOS 10 for a bit and suddenly stops downloading, throwing the error. I've also tried downloading a custom .ipsw from  but it seems that the file is corrupted whenever iTunes tries to unpack it.   Any thoughts on how I could go about fixing this?   Note - I don't have a jailbroken iPhone.


I am trying to do something I think is pretty easy but clearly making a pigs ears of it. Here is   I have a button and a label on display. I want to centre the label in the middle of the div, so horizontally and vertically centred.  I can centre it horizontally but not vertically. So I have tried a few things but nothing seems to centre the label vertically, even the vertical-align I use below. Not really sure why though?  .headerLbl {    text-align: center;    font-weight: bold;    color: white;    font-size: 14pt;     display: block;    vertical-align: central; }

I have a div with two images and an h1. All of them need to be vertically aligned within the div, next to each other. One of the images needs to be absolute positioned within the div. What is the CSS needed for this to work on all common browsers?

testing...


I have this question I posted at the Game Development Community.    Although the question is related to game development, I feel I can get more answer if I link or re-post the question at Stack Overflow. What's the proper thing to do?

My question is that I asked a question on stackoverflow.com and  I want to share my question to all other technical stackoverflow linked sites like ,  etc.  I want to share my question on only selected sites related to stackoverflow. I don't want to post duplicates, I just want to make my question visible for the users on the related site, that may not necessarily be the members of the both sites, but may be competent to answer.  Is there any option in StackExchange network to perform this operation?  Can any one suggest me how I can do this?


Integrate :   $$I=\int \frac{dx}{x\ln x}$$   I know this can be solved easily via substitution ($t=\ln x$) to obtain $I=\ln {\ln x} +C$, where $C$ is the constant of integration. But if we try to apply , choosing $\frac{1}{\ln x}$ as $u(x)$ and $\frac{1}{x}$ as $v'(x)$, something goes wrong: $$I=\frac{1}{\ln x}\cdot\ln x - \int \left(\frac{-1}{(\ln x)^2}\cdot\frac{1}{x}\cdot\ln x\right)dx$$ This reduces to $I=1+I$ or $1=0$. Why does this happen?

I've run into a strange situation while trying to apply Integration By Parts, and I can't seem to come up with an explanation.  I start with the following equation:  $$\int \frac{1}{f} \frac{df}{dx} dx$$  I let:  $$u = \frac{1}{f} \text{ and } dv = \frac{df}{dx} dx$$  Then I find:  $$du = -\frac{1}{f^2} \frac{df}{dx} dx \text{ and } v = f$$  I can then substitute into the usual IBP formula:  $$\int udv = uv - \int v du$$  $$\int \frac{1}{f} \frac{df}{dx} dx = \frac{1}{f} f - \int f \left(-\frac{1}{f^2} \frac{df}{dx}\right) dx$$  $$\int \frac{1}{f} \frac{df}{dx} dx = 1 + \int \frac{1}{f} \frac{df}{dx} dx$$  Then subtracting the integral from both sides, I've now shown that:  $$0 = 1$$  Obviously there must be a problem in my derivation here...  What wrong assumption have I made, or what error have I made?  I'm baffled.


When we consider a person on a ferris wheel, the forces acting on him at the top are the normal force and gravity. The acceleration of the person is downward (towards the center), so by Newton's second law we have (for the $y$ components of the respective forces)  $$n - mg = -m \frac {v^2} r \Leftrightarrow n = m\bigg(g - \frac{v^2}{r}\bigg)$$  Now when $\frac {v^2}r > g$ then $n$ becomes negatives, and supposedly you would then need a downward force (such as a seatbelt) to keep the passenger in the seat. I can't see how this follows, when $n$ is negative does the normal force even act on the person (since it's now pointing downward)?

A roller coaster car has a mass of 1360kg when fully loaded with passengers. As the car passes over a circular hill with radius 20m, its speed is not changing.   A.) What are the magnitude and direction of the force of the track on the car at the top of the hill if the cars speed is 11m/s?   B.) What are the magnitude and direction of the force of the track on the car at the top of the hill if the cars speed is 15m/s?   I have the correct answers according to the website I had to submit these answers to: A.) 5100N upward B.) 1972 downward  It was my understanding that at the top of the hill the acceleration due to circular motion and the acceleration due to gravity were in the same direction so an increase in speed would just increase the normal force which would be force of the track on the car. I don't get how there can be a force working in the downward direction.


What is the difference between the following sentences (in meaning)?  Are "present continuous" and "be going to" interchangeable?     I'm going to visit my brother on Friday.        I'm visiting my brother on Friday.

When she goes to Mexico, she will be visiting Chichen Itza. When she goes to Mexico, she will visit Chichen Itza.  Is there a particular difference in meaning, or it is just the matter of style?


In Ksh shell, my below command runs okay. test "$(($(date +%W)%4))" -eq 2 && echo "yes" > /u/crmprod/test  but it doesn't run in crontab using below. How to solve this please? 34 00 * * 2 test "$(($(date +%W)%4))" -eq 2 && echo "yes2" > /u/crmprod/test

I want to create a log file for a cron script that has the current hour in the log file name. This is the command I tried to use:  0 * * * * echo hello >> ~/cron-logs/hourly/test`date "+%d"`.log   Unfortunately I get this message when that runs:  /bin/sh: -c: line 0: unexpected EOF while looking for matching ``' /bin/sh: -c: line 1: syntax error: unexpected end of file   I have tried escaping the date part in various ways, but without much luck. Is it possible to make this happen in-line in a crontab file or do I need to create a shell script to do this?


so I'm making a program with a "controller" and two display screen's, kinda like Powerpoint when you press slideshow its open on the second screen in fullscreen. I have manage to do it with only two screens but every time I try with three I get a null pointer. here is my code:  import javax.imageio.ImageIO;  public class Program extends Canvas implements Runnable{ private static final long serialVersionUID = -7579474834886333524L;  private Thread thread; private boolean isRunning = false;  private Måler måler; private MålerLille målerlille;  public Program() {     new Controller();      målerlille = new MålerLille(1920, 1080, "screen3", this);     måler = new Måler(1920, 1080, "screen2", this);      GraphicsEnvironment ge = GraphicsEnvironment .getLocalGraphicsEnvironment();     GraphicsDevice[] gs = ge.getScreenDevices();      gs[2].setFullScreenWindow(MålerLille.frameML);     gs[1].setFullScreenWindow(Måler.frame);

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?