Obviously this is a Javascript problem. As javascript are already loaded to the server, I was wondering if there is way to check whether there is active internet connection or not.
How to detect the Internet connection is offline in JavaScript?
Filesystem shows /dev/nvme0n1p1 instead of /dev/sda I installed a dual boot of Ubuntu 16.04 (Windows being my other OS) two months ago to try it out. I want to allot more space to it on my hard drive. I was looking up tutorials, and I noticed that my filesystem names don't look anything like those in the tutorials. For example:  df -h   outputs:    How would I allot more space to Ubuntu (in layman's terms)? Was it just coincidence that Tahir Mahmood went on stage? In episode 3 of “Bodyguard,” Tahir Mahmood steps onto stage at St. Mary’s college as the Home Secretary is speaking and the two of them, plus others, are blown up by a bomb. In the next episode we discover that the stage had a weight trigger and that his arrival set it off. This heavily implies that whoever asked him to go on stage was affiliated with those who planted the bomb.  We know that Mahmood was sent on stage by advisor Rob Macdonald as part of a scheme, together with other members of the home secretary’s staff, to embarrass her. The audience knows that some of the people in on this scheme have been plotting with the U.K. security services. This, together with interference in video recordings of the event, characteristic of the security services, implicates the security services in the assassination.  In the final episode it is revealed that the bomb had been set by members of an organized crime gang who had gotten the explosives from an Islamic terrorist. A senior member of the police force had been helping them by leaking information. So, were the security services involved? If so, why? If not, who got Mahmood to go up on the stage? Was it just coincidence that he went up there at the right time? At what point is a creature's toughness calculated? If I have  where I can sacrifice a creature and put X 1/1 token creatures onto the battlefield, where X is the sacrificed creature's toughness.  If I have a creature that is 4/4 and cast  to give it +3/+3 then sacrifice it? Do I get 4 tokens or 7?  Also what if my 4/4 creature was dealt 2 combat damage before I sacrificed it? Do I get 2 or 4 creatures?  Finally, what about counters? If my 4/4 had a +1/+1 do I get 4 or 5 tokens? How do I lerp between values that loop (such as hue or rotation)? I'm trying to make the joint rotate smoothly around the center of the canvas, toward the angle of mouse pointer. What I have works, but I want it to animate the shortest distance possible to get to the mouse angle. The problem occurs when the value loops around at the horizontal line (3.14 and -3.14). Mouseover that area to see how the direction switches and it takes the long way back around.  Relevant Code   // ease the current angle to the target angle joint.angle += ( joint.targetAngle - joint.angle ) * 0.1;  // get angle from joint to mouse var dx = e.clientX - joint.x,     dy = e.clientY - joint.y;   joint.targetAngle = Math.atan2( dy, dx );   How can I make it rotate the shortest distance, even "across the gap"? PCA: Eigenvectors of opposite sign and not being able to compute eigenvectors with `solve` in R Co-Buyer Automobile As a co-buyer on an automobile, can the other party take full possession? Both parties names are listed as the Purchaser's. Only one purchaser signed the retail order for the motor vehicle, and if so, how can one become a no co-buyer? Python "if X == Y and Z" syntax I have a 250G disk on my Mac with around 100G in use. But the system reports only around 20G of free space. I'm using macOS 10.13.2. I have the problem at least since the upgrade to High Sierra, but probably also before.  "About This Mac" --> "Storage" reports that "System" is using around 180G. But if I check the complete disk, it looks like that:  $ sudo du -cxhd 1 /   0B    /.HFS+ Private Directory Data 1.0K    /home 4.3G    /usr 4.2G    /.Spotlight-V100 1.0K    /net  34G    /nix   0B    /.PKInstallSandboxManager   0B    /.PKInstallSandboxManager-SystemSoftware 2.6M    /bin   0B    /Network 1.1M    /sbin 3.8G    /Library   0B    /.Trashes 6.5G    /System 476K    /.fseventsd du: /private/var/db/ConfigurationProfiles/Store: Operation not permitted du: /private/var/folders/z7/[...]/0/SafariFamily: Operation not permitted du: /private/var/folders/z7/[...]/0/com.apple.LaunchServices.dv: Operation not permitted du: /private/var/folders/z7/[...]/0/com.apple.nsurlsessiond: Operation not permitted du: /private/var/folders/z7/[...]/0/com.apple.routined: Operation not permitted du: /private/var/folders/zz/[...]/0/com.apple.nsurlsessiond: Operation not permitted 8.0G    /private 8.6M    /.DocumentRevisions-V100   0B    /.vol  32G    /Users  11G    /Applications 207M    /opt 5.0K    /dev 4.0K    /Volumes   0B    /cores 104G    / 104G    total   df also says that only 20G are available:  $ df -h / Filesystem     Size   Used  Avail Capacity iused               ifree %iused  Mounted on /dev/disk1s1  234Gi  211Gi   20Gi    92% 4019132 9223372036850756675    0%   /   Any tool I was using (Finder, Disk Inventory X, etc.) shows more or less the same numbers like df and du.  Output of mount:  $ mount /dev/disk1s1 on / (apfs, local, journaled) devfs on /dev (devfs, local, nobrowse) /dev/disk1s4 on /private/var/vm (apfs, local, noexec, journaled, noatime, nobrowse) map -hosts on /net (autofs, nosuid, automounted, nobrowse) map auto_home on /home (autofs, automounted, nobrowse)   I read and tested many, many things like:         ... but with no success. So what could consume more than 100G of disk space without showing up in any tool?  Update  Running „First Aid“ in recovery mode:   What does this error message mean?  error: btn:1: invalid key order (1) oid 440198 / oxid 114577 fsroot tree is invalid.   Update 2018-01-25  Another report of the same error:  (but no answers, yet)  I'm pretty sure this file system error is the root cause for the missing disk space. But I have no idea how to fix that. I was hoping that 10.13.3 would maybe solve it, but it didn't change anything. I guess I need to reinstall... I have created multiple objects, while testing I applied a drop shadow style on one object and its looking very good. Now I want to apply the same style to all other objects (around 20). Is there any way like global color to create a style once and apply to other objects with single click automatically?  Or I have to apply that drop shadow effect on each object one by one manually? Quantum information references Recommended books for advanced undergraduate electrodynamics What should I look for when shopping for my first DSLR? I am thinking of buying a digital SLR camera. What things should I be looking for? Prove that $\nabla_{\mathrm X} \mbox{tr} (\mathrm A \mathrm X^{-1} \mathrm B) = - \mathrm X^{-\top} \mathrm A^\top \mathrm B^\top \mathrm X^{-\top}$ Prove that $$\nabla_{\mathrm X} \mbox{tr} (\mathrm A \mathrm X^{-1} \mathrm B) = - \mathrm X^{-\top} \mathrm A^\top \mathrm B^\top \mathrm X^{-\top}$$   My proof is below. I am interested in other proofs.    My proof  Let   $$f (\mathrm X) := \mbox{tr} (\mathrm A \mathrm X^{-1} \mathrm B)$$  Hence,  $$\begin{array}{rl} f (\mathrm X + h \mathrm V) &amp;= \mbox{tr} (\mathrm A (\mathrm X + h \mathrm V)^{-1} \mathrm B)\\ &amp;= \mbox{tr} (\mathrm A (\mathrm X ( \mathrm I + h \mathrm X^{-1} \mathrm V))^{-1} \mathrm B)\\ &amp;= \mbox{tr} (\mathrm A ( \mathrm I + h \mathrm X^{-1} \mathrm V)^{-1} \mathrm X^{-1} \mathrm B)\\ &amp;= \mbox{tr} (\mathrm A ( \mathrm I - h \mathrm X^{-1} \mathrm V + O (h^2)) \mathrm X^{-1} \mathrm B)\\ &amp;= \mbox{tr} (\mathrm A \mathrm X^{-1} \mathrm B) - h \, \mbox{tr} ( \mathrm A \mathrm X^{-1} \mathrm V \mathrm X^{-1} \mathrm B) + O (h^2)\\ &amp;= f (\mathrm X) - h \, \mbox{tr} ( \mathrm X^{-1} \mathrm B \mathrm A \mathrm X^{-1} \mathrm V ) + O (h^2)\end{array}$$  Thus, the directional derivative of $f$ in the direction of $\mathrm V$ at $\mathrm X$ is  $$D_{\mathrm V} f (\mathrm X) = - \mbox{tr} ( \mathrm X^{-1} \mathrm B \mathrm A \mathrm X^{-1} \mathrm V ) = - \mbox{tr} ( (\mathrm X^{-\top} \mathrm A^\top \mathrm B^\top \mathrm X^{-\top})^\top \mathrm V ) = - \langle \mathrm X^{-\top} \mathrm A^\top \mathrm B^\top \mathrm X^{-\top}, \mathrm V \rangle$$  and, lastly,  $$\nabla_{\mathrm X} \mbox{tr} (\mathrm A \mathrm X^{-1} \mathrm B) = - \mathrm X^{-\top} \mathrm A^\top \mathrm B^\top \mathrm X^{-\top}$$ Remove ajax call from regular links with jQuery Mobile How do I disable System Integrity Protection (SIP) AKA "rootless" on macOs [OS X] Apple has introduced , also known as "rootless", with OS X 10.11, El Capitan. I understand this is a step for general protection against malware but as a developer I need write access to some of the files it locks away.  How do I disable this protection? After Hoth, why did Vader pursue the Millennium Falcon instead of Luke's X-Wing? In The Empire Strikes Back film, the opening crawl says:     The evil lord Darth Vader, obsessed with finding young Skywalker, has dispatched thousands of remote probes into the far reaches of space....   It has also been established in Return of the Jedi that Force users can sense each other:     Chewie whines nervously. Luke stares at the Huge Super Star Destroyer    that looms ever larger before them.      LUKE: Vader's on that ship.   If Darth Vader is obsessed with finding Luke and he can sense his presence, the obvious thing to do would be to follow Luke's X-Wing after the battle of Hoth rather than the Millennium Falcon. Why didn't he? How do you split a list into evenly sized chunks? Why is the MacTeX distribution so large? Is there anything smaller for OS X? I would like to know how to install LaTeX on Mac 10.6 or higher.  But the MacTeX is some 1.28 GB file! Is there a smaller distribution I could install?  What exactly is TeX Live? How to zero out a drive? I'm currently running Ubuntu 12.04 and want to completely format my laptop so I can install Windows 7 (replace Ubuntu).   When I put in my bootable USB with the OS it just shows a black screen with a white blinking cursor on the top left corner. I wait for hours (to be specific 5 whole hours) waiting for something to happen but I get nothing, so I pull out the USB and my Ubuntu 12.04 loads up.  Repeated this several times with putting different boot priority options on top-est that relate to USB but the results are same. I go and visit some sites on the net like this  that say I have to zero out my hard drive.   My question is how?  Note: Erasing out all my data is no problem cause I have nothing important to backup.  If I have to lose my primary OS (Ubuntu 12.04) in the process I am ready to as my aim is just to install Windows 7 successfully. Please don't answer that there is something wrong with my USB or my USB reader/port/hardware or the content inside the USB cause they all works fine on my brothers PC as it boots up flawlessly. Why does arXiv have a multi-day lag between submission and publication? If you go on the  (now, 8th December 2020, 19:24 Italian time), there is for example the article &quot;Exploring the Usage of Online Food Delivery Data for Intra-Urban Job and Housing Mobility Detection and Characterization&quot;. This article is under the heading &quot;8 December&quot;. But if you , it was &quot;Submitted on 4 Dec 2020&quot;. Why there is a lag between submission time and the header under which it appears for recent publications? I guess the arXiv staff have to approve the article before is being published .... is my guessing correct?