I feel like I'm almost grasping it... like it intuitively makes sense but I don't know the details of why. Can someone explain:  Why here, global arr is NOT affected outside the function  arr = [1,2,3] function test(arr, a, b) {    arr = arr.filter(item => (a < item  && item < b))    console.log(arr) // [2] }  test(1, 3) console.log(arr) // [1,2,3]   Why here, global arr IS affected outside the function  arr = [1,2,3] function test(a, b) {    arr = arr.filter(item => (a < item  && item < b))    console.log(arr) // [2] }  test(1, 3) console.log(arr) // [2]   EDIT another example. Why here global arr IS affected outside the function EVEN THOUGH once again arr is passed as a parameter  arr = [1,2,3] function test(arr, a, b) {   for (let i = 0; i < arr.length; i++) {     let val = arr[i];     if (a >= val || val >= b) {       arr.splice(i, 1);       i--;     }   }   console.log(arr) // [2] } console.log(arr) // [2]

What is the scope of variables in javascript? Do they have the same scope inside as opposed to outside a function? Or does it even matter? Also, where are the variables stored if they are defined globally?


Let's say we have an image exhibition website that has got a lot of images but next to nothing content. The focus keyword for this website is "Artistic wallpapers". What would be the best approach w.r.t SEO for such a website.  Here are a few things I can imagine:   Submitting sitemaps ( image and web ) Having a good pagespeed score. Nice navigation Breadcrumbs sharing the website content on Social media. Having appropriate titles.   Having worked on all these things, what can be done if Search engines are picking wrong keywords ( For example views, votes, ratings) Can anything be done so that Search engines don't track these specific items? Also, is it a good practice to have all the pages submitted to Search engines at once?

What are the best ways to improve a site's position in the Google search results?


I am trying to convert KML File to shapefile, but all the fields are being deleted except the name.  How can I convert a KML/KMZ file to shapefile without losing the fields?

I've converted a shapefile with attributes to a .kml for a client.  The .kml and attributes were then edited within google earth.  I received the updated .kml and now I need to get it back to .shp.  The problem is: all of my attributes are now in html format, which makes the popup info box in google earth.  When I try to convert back to .shp my attributes get lumped into a (google created) "Description" field.  And ALL of my attributes and information is lumped into a single cell.  Is there some way to extract the data from the "Description" field.  Even if I do that, is there an easy way to get rid of the html format and make it usable?   This is what I get using the "Fusion Table" method I found on some forums.  You can see the html in the left, it continues on further than it shows.    I am using ArcGIS Desktop 10.2.


If i have a class like as below.  class A { int data; };  A a; // Case1: calling explicit Default constructor A b(); // Case2: Calling implicit default constructor   What is the difference between Case1 and Case2?

Is there any good reason that an empty set of round brackets (parentheses) isn't valid for calling the default constructor in C++?  MyObject  object;  // ok - default ctor MyObject  object(blah); // ok  MyObject  object();  // error   I seem to type "()" automatically everytime. Is there a good reason this isn't allowed?


I will admit I am ashamed at what I did, and a little anxious, but I’ll also share this in hopes that someone will either learn from this, or that someone will know what to do (or even give advice). I was naive roughly two weeks ago, and a sugar mama (or possibly scam) found me on a dating app. I was intrigued by the idea, being a young adult, as well as afraid to say no, so I went along. We started talking and eventually I gave my SSN, address, name: basically info I shouldn’t have. There were no sexual favors involved and they seemed nice, though they had broken English and repeated themselves often (signs I noticed afterwards). Eventually I got the hint that something was wrong, told them I would not give information, and blocked the number. A few days after I blocked the first number, another number texted me, but it happened to be the same person. This time, they were supposedly “pissed” and threatened my life, as well as to send someone after me and my family, saying I could not hide and to watch my back. Even going as far as to use my info for bad things (ironically, they’re threatening to do all that they promised they wouldn’t do before). I eventually told my mother, as scared as I was, and we’re now working on trying to stay safe. So far we called police for precaution and we’re in the process of getting a new number for me + new SSN, but I was wondering as to if we should genuinely worry. Is this a scam? Is this a real but obsessive sugar mama? Are we doing the right thing? Or is it too much? (I apologize if this was too long.)

I met a guy on a sugar daddy dating site and we talked, I told him my situation and he said he would help.   He asked for my bank account information and I told him you can use cash app or PayPal to go through. He said his account manager deals with his finances. So I set up an account with a bank that I don’t use so that my primary account isn’t used.  Eventually he was in the process of sending me money and we had agreed on a amount that wasn't crazy. But then he asked for my address and I asked why and he said just wondering. Then said he wanted to send me a surprise for being his baby. Which I didn’t give.  Then later on he sent the money and said he sent me a bonus and that I was supposed to use that to pay his mothers caregiver, which he didn’t mention until after.  I kept questioning him and he was saying that he works in construction and he’s trusting me to carry out the errand. Then he said don’t let him down and I asked him if he was threatening me and he kept saying I need this done but didn’t really answer my question.  Am I being scammed? I’m about to change my password but is this a scam?


I am a Zimbabwean on holiday in UK on a 6 month family visitor. I got a 30-day Schengen visa so I can visit Europe as well. I just want to find out if it is possible to extend the Schengen holiday visa from UK or Europe without having to go back to Zimbabwe first?

My daughter applied at the Italian Consulate in Philadelphia, and they gave her two entries for 20 days (we thought it was for 20 days each entry). She was in Italy 12 days, then went to England for 1 week and flew to Venice to take a 10-day cruise. She couldn't make it because they said she has only 8 remaining days, but she still has a land tour already paid this week.  What can she do? Can she extend the Schengen visa for 12 more days? Right now, she is in Madrid, but next week she has to fly from Barcelona to Paris to start with the tour. What would happen if she decides to take the tour with the expired visa? She is a US permanent resident.


I did it... I guess everyone does it sometime, but this was my first. I executed sudo chown -R /usr/bin and before I realized my mistake, it was too late... Now I can't access sudo because I receive the following error: sudo: must be setuid root. I would really appreciate if I could avoid a complete reinstall of ubuntu because that would require far too much work :(  Here is the commands I've tried without success (in recovery mode):  chown root:root /usr/bin/sudo chmod 4755 /usr/bin/sudo   I've also tried chmod 0440 /etc/sudoers all without success. Any ideas about what I can try to fix it?  NOTE: Sorry for creating another one of these threads, but since I knew the exact command I executed to blow it all up, I thought that might make a difference :)

I needed to edit a .config file (which I know for a fact is not creating these problems, just to clear that up) and it wouldn't let me save it, so I took ownership of /etc and all contents with the command chown -hR username /etc and that let me edit the .config file but now whenever I try to install any packages or use any sudo commands, it doesn't work  (I've checked for errors in the sudo file in sudoers.d and there was nothing wrong with that).   So how do I return it to the previous owner?


Let $R$ be a commutative and local ring, and $M$ is a right $R$-module and $N$ is a left $R$-module. If $M$ and $N$ are finitely generated, then $M\otimes_{R} N=0$ if and only if $M=0$ or $N=0$.   If $R$ is not local, then this proposition is true? Why?  I want to prove this proposition. But I don't know how to start. Please help me.   Thank you.

If $R$ is a local ring and $M$ and $N$ are finitely generated $R$-modules such that $M\otimes N=0$ then how does it follow from Nakayama's lemma that either $M=0$ or $N=0$?    This is an exercise in Atiyah and Macdonald. The part I could not show in the hints is $({M{\otimes}_R N)}_{k}=0$ implies $M_{k}{\otimes }_{k} N_{k}=0$, where $k=R/\mathfrak m$ and $\mathfrak m$ is the maximal ideal of $R$.


I am not able to identify this bug/insect.  I stay in Dubai and have been noticing this bug/insect in my apartment since a week now. It is so tiny that it's difficult to notice. The image below has been taken using a DSLR by placing it on a book page and cropped to more than 100% zoom.  I don't know the source, can feel it crawling on my skin and that's the only way to see it. One good thing is it cannot fly.   I went through all the questions about insect identification, but couldn't find any closest match for this. I also compared it to a book lice, but it's nowhere near to it.  I suspect it bites and leaves the skin itching with red spots similar to a mosquito bite. Does anyone know about this bug if it is harmful, and how to get rid of it?

I have seen these on my hands recently and I am wondering what they are. Urban Setting. South Central Pennsylvania.


i have installed ubuntu 14.5 LTS ,now i would like to upgrade it to 15. LTS .Without losing data and other applications i installed on ubuntu 14.4 LTS .Can it possible ?

So, today is July 21st and . gives me an option to download 16.04.1 LTS. However, attempting to upgrade gets me this message -  $ sudo do-release-upgrade Checking for a new Ubuntu release No new release found   What is wrong? Does it matter that I am running apt-get update behind apt-cacher-ng?  Note: Commenting out the files in apt.conf.d that used apt-cacher-ng did not make a difference.  Edit: Explanation for possible duplicates:  deals with upgrade from 12.04LTS to 14.04LTS. My question is specific to 14.04 LTS to 16.04.1 LTS upgrade. Old answers, while good for archival purposes are less relevant in a fast changing package like ubuntu. Moreover none of the answers answer what is wrong. The link  pointed out is mentioned in one of the comments. This Q & A is more helpful for people upgrading today than the work around mentioned in "".


Thinking of light in corpuscular form, how does the bouncing of a photon off a reflective surface work? Is it the same photon bouncing off, or is it absorbed and re-emitted?  If it's bouncing, does it do so without deceleration/reacceleration?  If it's being absorbed and re-emitted, what physical process guarantees that it's re-emitted at the exact same angle as it inceded on the reflective surface?

The "equal angles" law of refection on a flat mirror is a macroscopic phenomenon. To put it in anthropomorphic terms, how do individual photons know the orientation of the mirror so as to bounce off in the correct direction?


\documentclass{aip-cp}  \usepackage[numbers]{natbib} \usepackage{rotating} \usepackage{graphicx}  \newtheorem{theorem}{Theorem} \newtheorem{conjecture}{Conjecture} \newtheorem{define}{Definition}  \begin{document}   \begin{theorem}  Let $t(G)= \mathrm{something \  dummy} $. Then      \begin{enumerate}     \item $t(P_r)=r$;      \item $t(K_m \times P_r)= r+1 \ \mathrm{for} \  m \geq 2$;     \end{enumerate}     \end{theorem} \end{document}   Hi, as above.   How can i make the the numbering and the text "something dummy " and "for" as normal text n non-italic?  Thank you.

Lets say I have something like:   \[ Let x = number of cats \]   (This is a contrived example, but pretend we are actually inside a long align environment block...) "Let" and "number of cats" need to be written like normal text, while x= needs to be math type text.  I've seen this:  \[ \mbox{Let } x = \mbox{ number of cats} \]   and this:  \[ \textrm{Let } x = \textrm{ number of cats} \]   They seem to produce equivalent output, but I'm not sure which is the "correct" one. Also, they are not ideal in that the extra space needs to be placed inside the text mode block, otherwise it is ignored as math mode and butts the text right up against the math.  Ideally there would be some command which allowed embedding text into an equation, which correctly inserted leading and trailing space around the block as required without adding space inside the text block.  How does one do that "correctly"?


I just tried to copy a file from a PC with Linux to a USB flash drive like I did it some minutes before. Unfortunately, I could not click on the paste option anymore.  When attaching the same drive to a different PC with Windows 10 on it, it worked to paste files onto the PC. I switched back and forth multiple times, but no change.  Only after applying the automatic repair option in Windows and attaching the stick to Linux PC again, everything worked fine again there too.  If anybody has an idea of why it still worked on Windows, but not on Linux, I would be really interested in it.

Until recently both my Windows Partition (C:) and my Data Partition (E:) would mount as read/write. Now both seem to only mount as read-only.    GParted Resize (Error)  ntfsresize v2.0.0 (libntfs 10:0:0) Device name : /dev/sda4 NTFS volume version: 3.1 Cluster size : 4096 bytes Current volume size: 86207623680 bytes (86208 MB) Current device size: 86207627264 bytes (86208 MB) New volume size : 78662066688 bytes (78663 MB) Checking filesystem consistency ... Accounting clusters ... Space in use : 62126 MB (72.1%) Collecting resizing constraints ... Needed relocations : 1606868 (6582 MB) Schedule chkdsk for NTFS consistency check at Windows boot time ... Resetting $LogFile ... (this might take a while) Relocating needed data ... ERROR: Extended record needed (1032 > 1024), not yet supported! Please try to free less space.   chkdsk Output:     Checking file system on E: The type of the file system is NTFS. Volume label is Data.  A disk check has been scheduled. Windows will now check the disk.                            99482 file records processed.   495 large file records processed.                        0 bad file records processed.                            0 EA records processed.                                  0 reparse records processed.                             104412 index entries processed.                          0 unindexed files processed.                             99482 security descriptors processed.                    2466 data files processed.                              CHKDSK is verifying Usn Journal...   4479208 USN bytes processed.                                      Usn Journal verification completed. Windows has checked the file system and found no problems.  84187132 KB total disk space.   60479688 KB in 69969 files.      15520 KB in 2467 indexes.          0 KB in bad sectors.     174336 KB in use by the system.      65536 KB occupied by the log file.   23517588 KB available on disk.       4096 bytes in each allocation unit.   21046783 total allocation units on disk.    5879397 allocation units available on disk.  Internal Info: 9a 84 01 00 00 1b 01 00 fc 1a 01 00 00 00 00 00  ................ 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................ 42 00 00 00 52 73 5c 77 b0 e7 1d 00 b0 df 1d 00  B...Rs\w........   fstab  # /etc/fstab: static file system information. # # Use 'blkid' to print the universally unique identifier for a # device; this may be used with UUID= as a more robust way to name devices # that works even if disks are added and removed. See fstab(5). # # <file system> <mount point>   <type>  <options>       <dump>  <pass> proc            /proc           proc    nodev,noexec,nosuid 0       0 # / was on /dev/sda5 during installation UUID=8213cc89-2438-41b9-899f-13b4c5b299af /               ext4    errors=remount-ro 0       1 # swap was on /dev/sda6 during installation UUID=45873767-d9ae-4f0c-baab-ffc2726ac24e none            swap    sw              0       0   Checked the drive in GParted, GSmartControl and with ntfsfix, all completed successfully, no change.  Partitions  dev/sda1 NTFS WinRE dev/sda2 NTFS Windows C: dev/sda3 Extended dev/sda4 NTFS Data E: dev/sda5 EXT4 Ubuntu dev/sda6 linux-swap    I am looking for an explanation of:    Internal Info: 9a 84 01 00 00 1b 01 00 fc 1a 01 00 00 00 00 00  ................ 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................ 42 00 00 00 52 73 5c 77 b0 e7 1d 00 b0 df 1d 00  B...Rs\w........   and    Resetting $LogFile ... (this might take a while) Relocating needed data ... ERROR: Extended record needed (1032 > 1024), not yet supported! Please try to free less space.


I have been trying to share information concerning a conjecture that for all Prime numbers greater than 3, the difference between the their squares, modulus 24, is zero. I have tested this for the first 6 million primes without a contrary example. I am continuing the search but this is extremely time consuming. I realise that this information is trivial and only worthy of the briefest of notes, and I cannot find where to pass on the information. Does anyone know  where or who I can ask whether this is a known conjecture?

Suppose that $5\leq q\leq p$ are both prime. Prove that $24|(p^2-q^2)$.   This is what I got so far. I figured that since $p,q$ are bigger than $5$, there are only odd primes for this conjecture. Then I can rename $p=2m+1,q=2n+1,m,n∈Z$.  We want to show $(p^2-q^2 )=24k,k∈Z$. By substituting $2m+1$ for $p$ and $2n+1$ for $q$, we get  $((2m+1)^2-(2n+1)^2)$. If we expand it, we get $4(m^2+n^2+m-n)$ Q. I think I can make $4(m^2+n^2+m-n)$ look like $24k$. How should I approach ?  And my prof. commented that "I would take this proof in small steps.  Rather than trying initially to prove that $24 | p^2-q^2$, look at the progress you already have.  You proved $4 | p^2-q^2$.  Can you prove 8 is a factor?  What about 3?  Then see if you can put together what you have to get 24 as a factor."  I am stuck here. Any helps?


Let $A$ be a commutative ring with $1$ and $f\in A$ a non-nilpotent element. Then the set $\text{Spec}A_f$ has a natural one-to-one correspondence with the subset $D(f)\subset \text{Spec}A$ consisting of all $\mathfrak{p}\in \text{Spec}A$ with $f\notin \mathfrak{p}$. So $D(f)$ is an open subset of $\text{Spec}A$. Is it true that the natural map $\text{Spec}A_f\to \text{Spec}A$ is a homeomorphism onto $D(f)$? (I merely know that this map is a continuous injection onto $D(f)$.)

Let $$D(f)=\operatorname{Spec}A - V(f)=\{p\in \operatorname{Spec} A:f\notin p\}$$ be the principal open subsets of $\operatorname{Spec}A$ with the Zariski topology. I'm trying to prove that $D(f)\backsimeq \operatorname{Spec} A_f$, where $A_f$ is the localization of $A$ at $f$.  If we consider the canonical homomorphism $\varphi:A\to A_f$ given by $\varphi (a) = \frac {a}{1}$, we can define $\varphi':\operatorname{Spec} A_f\to \operatorname{Spec} A$, given by $\varphi'(p)=\varphi^{-1}(p),\forall p\in \operatorname{Spec}A_f$.  I'm having trouble proving that this map is surjective.  Thanks.


Let $X$ be a set. What is $X\times \emptyset$ supposed to mean? Is it just the empty set?

If we have a function $f:A \rightarrow B$, then one way to give meaning, I think, to this function, in terms of set theory, is to say, that $f$ is actually a binary relation $f=(A,B,G_f)$, where $G_f \subseteq A \times B$ is the graph of the function. Now my question is: what is $f$ if   $\bullet \ A=\emptyset, \ B\neq\emptyset$,?  $ \bullet \ B=\emptyset, \ A\neq\emptyset$ ?  $ \bullet \ B=\emptyset, \ A=\emptyset$ ?  (Another way to formulate this, I think, would be: How do the sets $\emptyset\times B,\ A\ \times \emptyset, \ \emptyset \times \emptyset $ look like? Are they all $\emptyset$ ?)


What is the difference between using #include<filename> and #include<filename.h> in ? Which of the two is used and why is it is used?

In the C and C++ programming languages, what is the difference between using angle brackets and using quotes in an include statement, as follows?   #include <filename>  #include "filename"


I want to run a simple command after boot. cd /mypath then ./mycommand How can I do it? Thnx

How can I run scripts automatically when Ubuntu starts up so I don't have to run them manually after startup?


I installed Ubuntu 12.04.5 (64 bit) on a Dell T5500 with two Xeon 5650 6-core processors specifically to run the free DCP-o-matic software (). The same machine used all 24 virtual cores before under Windows 7 Professional 64 bit, but I was just not happy with that OS.  Under Ubuntu the performance was less than 1/10 of what I had experienced under Windows. I next upgraded to 14.04.2 but to no avail. Monitoring the resources makes it clear that the processors are throttled down after reaching their peak performance. The pattern looks like saw teeth.  Here is a screenshot   What can I do to achieve maximum performance? Any help is very much appreciated!

In 10.10, I remember I had CPU Frequency Scaling Monitor by default. Now in 12.04, I cannot find anything similar in Ubuntu software center. I wonder what applications are recommended for scaling CPU frequency in 12.04, and how to get and install them?  Thanks and regards!


I am using texmaker and I include eps figures. The code is very long but I will include some of it.  \documentclass[draft, 12pt, onecolumn]{IEEEtran} \usepackage{graphicx} \usepackage{epstopdf}  \begin{document}  \begin{figure}[!t] \centering \includegraphics[scale=0.4]{./Figures/RL_NE.eps} \caption{Percentage of playing good} \label{fig_1} \end{figure}  \end{document}   When I open my compiled file I will get the following:   I do not know where is the problem. I am compiling with PdfLatex.

I'm using IEEEtran to format an article, and I wanted to include an image. I included the graphicx and hyperref packages, and used the following code, like normal, to include an image.  \begin{figure}[!t] \centering \includegraphics[width=3in]{fetch} \caption{Pipeline: Fetch Instruction} \label{fig:fetch} \end{figure}   What appears, however, is this:    Fetch.png is a file in the directory, and if I remove it, pdflatex errors instead of producing an output. I'm using MiKTeX 2.9 on Windows 7. Any ideas?


When I try to run something like sudo apt-get install rdesktop, I get this:  Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies:  linux-image-generic-lts-trusty : Depends: linux-image-3.13.0-55-generic but it is not going to be installed E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).   When I then trying running sudo apt-get -f install, I get this:  Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following extra packages will be installed:   linux-image-3.13.0-58-generic linux-image-generic-lts-trusty Suggested packages:   fdutils linux-lts-trusty-doc-3.13.0 linux-lts-trusty-source-3.13.0   linux-lts-trusty-tools linux-headers-3.13.0-58-generic The following NEW packages will be installed:   linux-image-3.13.0-58-generic The following packages will be upgraded:   linux-image-generic-lts-trusty 1 upgraded, 1 newly installed, 0 to remove and 83 not upgraded. 2 not fully installed or removed. Need to get 0 B/52.5 MB of archives. After this operation, 198 MB of additional disk space will be used. Do you want to continue [Y/n]? y (Reading database ... 353075 files and directories currently installed.) Unpacking linux-image-3.13.0-58-generic (from .../linux-image-3.13.0-58-generic_3.13.0-58.97~precise1_amd64.deb) ... Done. dpkg: error processing /var/cache/apt/archives/linux-image-3.13.0-58-generic_3.13.0-58.97~precise1_amd64.deb (--unpack):  failed in write on buffer copy for backend dpkg-deb during `./boot/vmlinuz-3.13.0-58-generic': No space left on device No apport report written because the error message indicates a disk full error                                                                               dpkg-deb: error: subprocess paste was killed by signal (Broken pipe) Examining /etc/kernel/postrm.d . run-parts: executing /etc/kernel/postrm.d/initramfs-tools 3.13.0-58-generic /boot/vmlinuz-3.13.0-58-generic run-parts: executing /etc/kernel/postrm.d/zz-update-grub 3.13.0-58-generic /boot/vmlinuz-3.13.0-58-generic Errors were encountered while processing:  /var/cache/apt/archives/linux-image-3.13.0-58-generic_3.13.0-58.97~precise1_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)   Can anyone help me to understand what's going on here? I have read some related questions but am a bit confused.

My first issue was when I tried to apt-get update or apt-get upgrade. On upgrade I get the following error:  You might want to run 'apt-get -f install' to correct these. The following packages have unmet dependencies: linux-image-server : Depends: linux-image-3.2.0-27-generic but it is not installed E: Unmet dependencies. Try using -f.   I tried running apt-get install -f and this was the output(after saying yes on prompt)  (Reading database ... 186183 files and directories currently installed.) Unpacking linux-image-3.2.0-27-generic (from .../linux-image-3.2.0-27-generic_3.2.0-27.43_amd64.deb) ... Done. dpkg: error processing /var/cache/apt/archives/linux-image-3.2.0-27-generic_3.2.0-27.43_amd64.deb (--unpack):  failed in write on buffer copy for backend dpkg-deb during `./boot/System.map-3.2.0-27-generic': No space left on device  No apport report written because the error message indicates a disk full error                                                                           dpkg-deb:    error: subprocess paste was killed by signal (Broken pipe) Examining /etc/kernel/postrm.d . run-parts: executing /etc/kernel/postrm.d/initramfs-tools 3.2.0-27-generic   /boot/vmlinuz-3.2.0-27-generic run-parts: executing /etc/kernel/postrm.d/zz-update-grub 3.2.0-27-generic /boot/vmlinuz-3.2.0-27-generic Errors were encountered while processing: /var/cache/apt/archives/linux-image-3.2.0-27-generic_3.2.0-27.43_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)   I tried running apt-get autoremove and it gives me the same error as apt-get upgrade.  When I run df, I get this for /boot:  /dev/sda1                    233191     230297         0 100% /boot   So, I read elsewhere that I should try to purge old kernels. I checked for what kernels I had with:  $ dpkg -l linux-image-\* | grep ^ii ii  linux-image-2.6.38-13-server  2.6.38-13.52  Linux kernel image for version 2.6.38 on x86_64 ii  linux-image-3.0.0-13-server   3.0.0-13.22   Linux kernel image for version 3.0.0  on x86_64 ii  linux-image-3.0.0-14-server   3.0.0-14.23   Linux kernel image for version 3.0.0  on x86_64 ii  linux-image-3.0.0-15-server   3.0.0-15.26   Linux kernel image for version 3.0.0  on x86_64 ii  linux-image-3.0.0-16-server   3.0.0-16.29   Linux kernel image for version 3.0.0  on x86_64 ii  linux-image-3.0.0-17-server   3.0.0-17.30   Linux kernel image for version 3.0.0  on x86_64 ii  linux-image-3.2.0-24-generic  3.2.0-24.39   Linux kernel image for version 3.2.0  on 64 bit x86 SMP ii  linux-image-3.2.0-25-generic  3.2.0-25.40   Linux kernel image for version 3.2.0  on 64 bit x86 SMP ii  linux-image-3.2.0-26-generic  3.2.0-26.41   Linux kernel image for version 3.2.0  on 64 bit x86 SMP   When I try to remove the oldest with this:  $ sudo apt-get purge linux-image-2.6.38-13-server Reading package lists... Done Building dependency tree Reading state information... Done You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies: linux-image-server : Depends: linux-image-3.2.0-27-generic but it is not going to be     installed E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).   How can I free up or extend boot without messing up my installation?


I have one function named root and at next part I am storing function name in variable (call) . I want to call function by using variable name For Example:-  (note:- not using root() using variable call's value )   call = "root";   root = function() {     name = "This is My root function";     console.log(name)  }    Can we call root function by value of variable (call) Is it possible.

I have the name of a function in JavaScript as a string. How do I convert that into a function pointer so I can call it later?  Depending on the circumstances, I may need to pass various arguments into the method too.  Some of the functions may take the form of namespace.namespace.function(args[...]).


I can't close questions on mobile right now.   The page just jumps to the top and nothing else happens.   (And what kind of quality standards are preventing me from asking this question?)

This morning (it's about six AM here) I find that I can no longer submit close votes; the link just jumps to the beginning of the page.  I'm on iOS, using a third-party browser called Grazing, but a brief check with Mobile Safari shows the same problem there.   Here on Meta, where my score is much lower, I only get a "delete" link on my own question, and that works fine. (Oops :-))   Update: As per comments, this affects the "flag" link, too, which doesn't even scroll to the top of the page. Update 2: Latest comment suggests this affects Android, too. Update 3: This also affects desktop computers when viewing mobile (when you click "mobile" in the footer) Update 4:  mentions Windows 8, too; simply deleting platform-specific tags


I have found and read full  which is useful to edit/add the question or answer.  It looks so pretty for me and to all.  My question is: Is there any format to show the badge as it is visible on profile or badges list?  Example: For tag format, I used [tag:tagname] which gives the output like: .   But I have not found any such formatting option for badges which will give us the output like:     If anybody has idea how to get such format then let me know. And if there is no such format then I request to add this format.  I also want the reviews from other users that is it good idea as there are more than 1.5K questions related to this and there are no lighlighting for badges names?

I always found it odd that although I could compose  and  with  in , I can't do the same for a , , or . I assume that this is because, outside of Meta Stack Overflow, there is no real need to reference badges? Be that as it may, would there be any interest in adding badges to Markdown? I am envisioning a syntax similar to the one used for tags. For example,  [badge:great-question] Question score of 100 or more. This badge can be awarded multiple times.  or ( ):  [gold-badge:great-question] Question score of 100 or more. This badge can be awarded multiple times.  would be displayed as  Note that I am not proposing that you need to enter the badge description to display the badge, nor that the badge description will be automatically inserted. Typing [badge:great-question] (or [gold-badge:great-question]) would be sufficient to display the "Great Question" badge, which would ideally have a tooltip with the badge description and link to the badge page. (I used the badge description text in the example above only because it was easier to take a screenshot that way.)  and  are great examples of posts that would benefit from the addition of badges to Markdown. UPDATE:  has brought it to my attention that the idea of a badge creator is not a new one. Check out this post for .      , until inevitably . Luckily,   (as of May 23, 2013). Given the popularity and utility of these badges—their use in jokes notwithstanding—wouldn't it be better to have Stack Overflow host this functionality itself rather than have users rely on an external service that will inevitably go down?


The problem  Let's consider the interval $[0, 1]$. We break this interval randomly in two parts. Then we choose the bigger part and again we break it randomly into two parts. At the end we have three parts of the interval. Breaking points are distributed uniformly. I am to find the probability of getting a triangle from these three pieces.  My attempt  First of all let's notice that a triangle can be build iff:   $a+b>c$, $|a-b| < c$,   where $a, b, c$ are lengths of our triangle sights.  Let's denote the breaking points by $x$ and $y$. Suppose $x > \frac{1}{2}$. We do have three intervals after breaking our segment: $[0, y], [y, x], [x, 1]$.  The first condition of triangle's existence is trivially fulfilled. The second one implies: $$y > x - {1}{2} \text{  and  } y < \frac{1}{2}.$$ I calculated that: $$f_{Y|X}(y|x) = \frac{f(x, y)}{\int \limits_{\infty}^{\infty}f_X(x) \mathbb{1}_{[0,x]}(y) \mbox{d}y}.$$ Where $f(x) = \mathbb{1}_{[0,1]}(x)$ and $f(x, y) = \mathbb{1}_{[0,1]}(x)\mathbb{1}_{[0,x]}(y)$.  I don't really know how the integration should look like. I would appreciate any tips or hints.

Randomly break a stick (or a piece of dry spaghetti, etc.) in two places, forming three pieces.  The probability that these three pieces can form a triangle is $\frac14$ (coordinatize the stick form $0$ to $1$, call the breaking points $x$ and $y$, consider the unit square of the coordinate plane, shade the areas that satisfy the triangle inequality edit: see comments on the question, below, for a better explanation of this).  The other day in class*, my professor was demonstrating how to do a Monte Carlo simulation of this problem on a calculator and wrote a program that, for each trial did the following:   Pick a random number $x$ between $0$ and $1$.  This is the first side length. Pick a random number $y$ between $0$ and $1 - x$ (the remaning part of the stick).  This is the second side length. The third side length is $1 - x - y$. Test if the three side lengths satisfy the triangle inequality (in all three permutations).   He ran around $1000$ trials and was getting $0.19$, which he said was probably just random-chance error off $0.25$, but every time the program was run, no matter who's calculator we used, the result was around $0.19$.  What's wrong with the simulation method?  What is the theoretical answer to the problem actually being simulated?  (* the other day was more than $10$ years ago)


What preposition is best in this sentence?            I would rather you arrived on time to school.       I would rather you arrived on time for school.

I was looking on the internet but really haven't found anything definite on this. I was writing a letter for IELTS practice and I came with this phrase:     "When I arrived to the school I really did not know what to expect.".   I'm doubtful about whether the "to" is well placed there.  I think the following option with "at" instead of "to" sounds better as in:     "When I arrived at the school I really did not know what to expect."   but I'm not sure if those two are interchangeable in this particular example.


After compiling, I receive several warnings of the following form:  Author undefined for citation`Lin1995' (natbib) on page 25   Here are some examples:   The relevant LaTeX code:  For instance,~\citeauthor{Lin1995} observed...   The corresponding text in the compiled document appears as:  For instance, (author?) observed...   The .bib entry:  @article{Lin1995, annote = {less than half the corrision rate for any boundary fraction.}, author = {Lin, P and Palumbo, G and Erb, U. and Aust, K.T.}, doi = {10.1016/0956-716X(95)00420-Z}, file = {:C$\backslash$:/Users/Oliver/Documents/Research/MIT/Papers/Influence of grain boundary character distribution on sensitization and intergranular corrosion of alloy 600 - Lin.pdf:pdf}, issn = {0956716X}, journal = {Scripta Metallurgica et Materialia}, month = nov, number = {9}, pages = {1387--1392}, title = {{Influence of grain boundary character distribution on sensitization and intergranular corrosion of alloy 600}}, url = {http://linkinghub.elsevier.com/retrieve/pii/0956716X9500420Z}, volume = {33}, year = {1995} }  But sometimes it gets the citation, just not the author, as in:  ...the spectral framework of~\citet{Johnson2013}...   which appears as:  ...the spectral framework of (author?) [40]...   and here is the .bib entry:  @article{Johnson2013, author = {Johnson, Oliver K and Schuh, Christopher A}, doi = {10.1016/j.actamat.2013.01.025}, file = {:C$\backslash$:/Users/Oliver/Documents/Research/MIT/Papers/The uncorrelated triple junction distribution function - Johnson.pdf:pdf}, issn = {13596454}, journal = {Acta Materialia}, keywords = {grain boundary engineering,microstructure design,triple junction,triple junction distribution function}, month = may, number = {8}, pages = {2863--2873}, title = {{The uncorrelated triple junction distribution function: Towards grain boundary network design}}, url = {http://linkinghub.elsevier.com/retrieve/pii/S1359645413000529}, volume = {61}, year = {2013} }    Here is my preamble, in case it is helpful:  \documentclass[12pt,twoside,singlespace]{mitthesis} \usepackage{lgrind} \usepackage{cmap} \usepackage[T1]{fontenc} \pagestyle{plain}  %---packages---% \usepackage{amsmath} \usepackage{amsfonts} \usepackage{amssymb}  \usepackage{graphicx} \usepackage{mathtools} \usepackage{cases} \usepackage[font=footnotesize]{caption} \usepackage[section]{placeins}  \usepackage{leftidx} \usepackage{mathrsfs} \usepackage{bm} \usepackage[numbers,sort&compress]{natbib}  %---macros---% \newcommand{\threej}[6] {\begin{pmatrix} #1 & #2 & #3 \\ #4 & #5 & #6 \end{pmatrix}} \newcommand{\sixj}[6] {\begin{Bmatrix} #1 & #2 & #3 \\ #4 & #5 & #6 \end{Bmatrix}} \newcommand{\ninej}[9] {\begin{Bmatrix} #1 & #2 & #3 \\ #4 & #5 & #6 \\ #7 & #8 & #9 \end{Bmatrix}} \newcommand{\so}[1]{\ensuremath{SO\left( #1 \right)}} \renewcommand{\(}{\left(} \renewcommand{\)}{\right)} \renewcommand{\d}{\mathrm{d}} \renewcommand{\figurename}{Fig.}  \DeclareMathOperator{\real}{Re\!} \DeclareMathOperator{\imag}{Im\!} \newcommand{\suchthat}{\;\ifnum\currentgrouptype=16 \middle\fi|\;} \newcommand{\conj}{\,^{\scalebox{1}{$*$}}} \newcommand{\CG}[6]{C_{#1,#2,#3,#4}^{#5,#6}} \renewcommand{\(}{\left(} \renewcommand{\)}{\right)} \renewcommand{\d}{\mathrm{d}}

I have a quick question about updating my references from Bibtex.  I am using TexStudio as my Latex editor.  I have to make changes to some of the references.  I put the changes in the "references.bib" file.  I then compile the Bibtex and the main document I'm working on.  Sometimes the changes show up, and sometimes they don't, and I haven't figured out why. I have even gone as far as trying to delete the references by changing the filename, but the original references still appear.  Here's what I put in my main document:   \newpage %Puts in References  \bibliographystyle{unsrt}  \bibliography{references}   My references.bib file shows all the changes I have made.  Any suggestions are appreciated!


I am trying to figure out which of the following two is correct:    I don't know who is whom in this chat? I don't know who is who in this chat?   I tried to figure it out myself, but it quickly get's really complicated. Thanks for your help!

I can never figure out whether I should use who and whom. Most people use who for both colloquially, but some people say this is not correct.  What’s the rule for using who and whom correctly?


How to make a video responsive using the Media:vimeo and Media:youtube modules?  I read somewhere to add some css:  .file-video-vimeo{   padding-top:56.25%; /*16:9 aspect ratio*/   position:relative; }  .media-vimeo-video{   position:absolute;   top:0;   left:0;   right:0;   bottom:0; }   ..and to set both width and height to 100% in the video display settings.  However, this does not work for me, it does not show full width of its container.  I see in my page html that for the vimeo player, vp-player-layout js-playerLayout  has   left: 40px;     right: 40px;     top: 0px;     bottom: 0px;   Why is this? This causes the video not to be the full width.

I currently use the  module to embed Youtube videos in my posts, but on mobile devices the videos are not responsive. They still maintain their width no matter how narrow the screen is.  I am open to another method of embedding videos even raw HTML and Javascript if the video displays will be responsive


So the series is $$P_k: 2^2 + 4^2 + 6^2 + ... + (2k)^2 = \frac{2k(k+1)(2k+1)}3$$  and i have to replace $P_k$ with $P_{k+1}$ to prove the series.  I have to show that $$\frac{2k(k+1)(2k+1)}3 + [2(k+1)]^2 = \frac{2(k+1)(k+2)(2k+3)}3$$ but I don't know how.

I am just starting into calculus and I have a question about the following statement I encountered while learning about definite integrals:  $$\sum_{k=1}^n k^2 = \frac{n(n+1)(2n+1)}{6}$$  I really have no idea why this statement is true. Can someone please explain why this is true and if possible show how to arrive at one given the other?


I have Ubuntu 15.04 26G in the / 4G in Swap and 70 in /home and i have win10 on a dual boot taking 20G all on a 120G hard drive  now i need more space on the win10 partition let's say 20G more and i need to take it from the 70G /home without the risk of losing any data

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?


xPath in SelectNodes method below does not return any node, even if there are such nodes in xCurrent document.  XmlDocument xCurrent = new XmlDocument(); xCurrent.Load(File); foreach (XmlNode Node in xCurrent.DocumentElement.SelectNodes("//Product")) {     ... }   My assumption that it should is based on this:   //author All <author> elements in the document.  However I've found that following xPath returns what is required  xCurrent.DocumentElement.SelectNodes("//*[local-name()=\"Product\"]"))   It seems for me that xPath assumes that "//Product" means "//elibri:Product", because "//" xPath returns only "elibri:Dialect" node. What is the reason behind that assumption? List of child nodes of DocumentElement is below.

I've got an XML document with a default namespace. I'm using a XPathNavigator to select a set of nodes using Xpath as follows:     XmlElement myXML = ...;   XPathNavigator navigator = myXML.CreateNavigator(); XPathNodeIterator result = navigator.Select("/outerelement/innerelement");   I am not getting any results back: I'm assuming this is because I am not specifying the namespace. How can I include the namespace in my select?


For which values of  ''$a$'',   does the integral $$\int_{0}^{\infty} \frac{\sin x}{x^a}\;\mathrm dx$$ converges?  I have shown that  $$\left| \int_{0}^{\infty} \frac{\sin x}{x^a}\;\mathrm dx \right|\le \lim_{n\to\infty} \int_{0}^{n} \frac 1{x^a}\;\mathrm dx,$$ which converges if $a > 1$. Are there other values of $a$ for which the integral converges?

For what values of $\alpha>0$ this integral converges $$\int_0^{\infty} \frac {\sin x}{x^{\alpha}}dx $$


How do I find the square root of complex number $7-(6\sqrt2)i$?   I hope there's someone who can show me the method. Thanks in advance.

If I'm given a complex number (say $9 + 4i$), how do I calculate its square root?


I have two domains registered with NameCheap and I'm pointing them to GitHub Pages. I noticed that when I use GitHub link (eg. ) the connection is reasonably fast, but when I use the domain () that is configured as GitHub says, the first connection is so slow.  I checked on Chrome Developers Tool and during the first connection I usually have a 1s Proxy negotiation delay. Could be this caused by NameCheap DNS servers? Are they really so slow? And, in this case, any good alternative?

I've been trying to optimize my site as much as possible. One thing I can't figure out is reducing first byte time as WebPagetest gives me an "F". Does anyone have any tips for this? My site domain is registered through GoDaddy and hosted on GitHub pages.


I am working on float numbers as part of my project and I ran into this issue. I have two floats that are different. However, when I try to print them, it prints the same value. Can someone please help me understand what's happening? Is it related to the number of fractional digits that can be printed on the console? Following is the MWE. #include<stdint.h> #include<iostream>  union FP32 {     float f;     uint32_t bits; };  int main(void) {          FP32 a, b;     a.bits = 0x40800000;     b.bits = 0x407FFFFF;     std::cout << a.f << std::endl;     std::cout << b.f << std::endl;     return 1; }

In my  I was printing a double using cout that got rounded when I wasn't expecting it.  How can I make cout print a double using full precision?


I used to click on "Hot Questions" in the top bar as I am fond of them. But I cannot do that now ever since the top bar was redesigned. I now have to visit  for that. Why was it removed? And are there plans to bring it back?

Since the new top bar has been rolled out - a number of different people, established and new users alike, have asked questions on where a specific link has disappeared to with the new top bar design. Where has the link to <X> gone?


I am not getting notified when the Find My iPhone app is used or even if I try searching via iCloud. How can I enable them?

If I use Find my iPhone to locate my son's phone, does he know I am checking?  Does his phone alert him that I'm checking on him?


The Question:  For the real vector space $V$, let $u,v \in V$ and $\{ e_1,\dots,e_k \}$ being a set of orthonormal vectors wrt to the inner product $\langle \cdot \;,\;\cdot \rangle$. Prove that  $$\biggl (\sum_{i=1}^k \langle u\;,\;e_i \rangle \langle v\;,\;e_i\rangle \biggr)^2≤ \Vert u \Vert^2 \, \Vert v \Vert^2$$    My Attempt:  $\{ e_1,\dots,e_k \}$ being orthonormal means that we can extend it to an orthonormal basis $\{ e_1,\dots,e_n \}$ for $V$ (where $n≥k$ of course).  So let $u=\sum_{i=1}^n u_i e_i$ and $v=\sum_{i=1}^n v_i e_i$ for some $u_1,\dots ,u_n,v_1, \dots ,v_n \in \Bbb R$. Then  \begin{align} \biggl (\sum_{i=1}^k \langle u\;,\;e_i \rangle \langle v\;,\;e_i \rangle \biggr)^2 & = \biggl (\sum_{i=1}^k \langle \sum_{j=1}^n u_j e_j\;,\;e_i \rangle \langle \sum_{j=1}^n v_j e_j\;,\;e_i \rangle \biggr)^2 \\  & =  \biggl (\sum_{i=1}^ku_iv_i \biggr)^2 \end{align}  and I am stuck.  If only I could show that  $$\biggl (\sum_{i=1}^ku_iv_i \biggr)^2≤\biggl (\sum_{i=1}^nu_iv_i \biggr)^2$$  then using Cauchy-Schwarz Inequality would get us there directly.  Any hints?

Let $V$ be a real inner product space, and let $v_1,v_2, \dots ,v_k$ be an orthonormal set of vectors. How do you prove that  $$\sum_{i=1}^k | \langle x,v_i \rangle \langle y,v_i\rangle| \leq \|x\|\cdot\|y\|?$$  When does the equality hold?  I've been trying to do this with the Bessel and Cauchy-Schwarz inequalities, but I can't make it work yet. Any help would be greatly appreciated.


Now I am a proud owner of Nikon D5300 DSLR equipped with an 18-55 kit lens. This is the first time I am dealing with DSLR. I don't want to use as a mere point-n-shoot camera, but want to use it to its fullest extent. I feel the need of taking a full-length, in-depth online free photography course which will take me to the DSLR world. Can anyone please suggest me any such course which explores the key areas in DSLR photography?

What are good resources (tutorials/books/videos/etc) for a beginning photographer?  Keep in mind that this is for a beginning photographer, who has recently moved from a point-and-shoot to an entry-level DSLR, and is interested in digging deeper into photography in general.  Examples of good topics for the resources to cover:   what's aperture?, and other camera basics  color temperature and lighting composition and visualization etc.


Let $\{x_n\}_{n \in\mathbb{N}}$ be a bounded sequence of real numbers. Let us define, for each ${n \in\mathbb{N}},$ $$y_n = \sup\{x_k : k \geq n\}$$ and $$z_n = \inf\{x_k : k \geq n\}.$$  Prove that the sequence $\{x_n\}_{n \in\mathbb{N}}$ is convergent if and only if $\displaystyle \lim_{n \rightarrow \infty} y_n = \lim_{n \rightarrow \infty} z_n$.

This is a question with a few components to it. In each one, I give my attempt at a solution. Thank you in advance for any suggestions/answers/advice on how to solve this problem.   For bounded sequences which do not converge, these are notions which sometimes can substitute for the non-existent limit.  Let $\{a_n\}$ be a bounded sequence. Define $T_n = \{a_i : i \geq n\}$ denote the n-th "tail" of the sequence and let $\overline{b}_n = \sup T_n$ and $\underline{b}_n = \inf T_n$.  a). Prove the sequences $\{\overline{b}_n\}$ and $\{\underline{b}_n\}$ both converge.   Given that $\{a_n\}$ is a bounded sequence and $\overline{b}_n = \sup T_n$ and $\underline{b}_n = \inf T_n$, then we have for the supremum, by defintion, that there exists a least upper bound, call it $\overline{m}$, such that $x \leq \overline{m}$ for all $x \in \{a_n\}$. Similarly, there exists a greatest lower bound $\underline{m}$ such that $x \geq \underline{m}$ for all $x \in \{a_n\}$. This is where I am stuck because I want to say that because $\overline{b}_n$ is given to be our $\sup T_n$, then we have a monotone sequence which converges by the Completeness Property. But is this a safe assumption at this point? This doubt is the same for the latter case, except we change our argument so that it states it using $\underline{b}_n$ as the $\inf T_n$.    b). We now define $\lim \sup a_n = \lim \overline{b}_n$, and $\lim \inf a_n = \lim \underline{b}_n$. Find $\lim \sup$ and $\lim \inf$ for the sequence $a_n = \frac{1}{n} + (-1)^n$.  For this part of the problem, I have an intuitive understanding about the $\lim \sup a_n = 1,$ and the $\lim \inf a_n = -1$, but am not sure how to formally state this.   c). Prove that $\lim \inf a_n \leq \lim \sup a_n$.  Similar to above, intuitively, I believe that this is true since the $\inf a_n$ is the greatest lower bound and that $\sup a_n$ would be the least upper bound. However, I then consider the empty set as a counterexample (is this valid)?  d). Prove that: $\lim a_n$ exists $\iff$ $\lim \inf a_n = \lim \sup a_n$.  As far as this step, I would not know how to get an 'if and only if' proof for $\lim \inf a_n = \lim \sup a_n$.  The only thing that I could think of is knowing from previous courses that the limit is unique, and that it must approach the same value from either side.   Again, thank you very much for taking the time to read/answer/post on this rather lengthy question. I am using the textbook Introduction to Analysis by Arthur Mattuck.


I'm new to film photography and I have the Pentax k 1000  when I look through the view finder I see two circles  one small one in the center surrounded by another larger circle...  what do these circles mean/do?  say im taking a picture of a flower do I need to line that flower up in the circle?  just not sure what both of them are for  thanks!

I've seen a couple other questions such as  one talk about focusing screens. What is a focusing screen? Where is it located?


A Lie group can be defined as a differentiable manifold. Is it possible to import the notion of Riemannian metric on differentiable manifolds to define a canonical metric on a Lie group?

Given a connected Lie Group $G$ is there a standard method for constructing the metric tensor?  One can of course expand a group element $g=e^{x^ie_i}$ where $e_i$ are basis vectors of the Lie algebra about the identity up to linear order and compute the metric in this manner, but is there a more direct way?   An example would also be appreciated.


I was just wondering if all of the Sith Star Destroyers from The Rise of Skywalker were destroyed in the Rebel fleet's attack or if there are some that survived, possibly beneath the surface of the planet.  Canon sources preferred, please.

In the movie The Rise of Skywalker, Emperor Palpatine dispatches the Xyston-class Star Destroyer Derriphan to the planet Kijimi to destroy it, and it does so using its axial superlaser.  I am curious to know if the Derriphan had immediately returned to the planet Exegol, participated in the Battle of Exegol, and was destroyed with the other Star Destroyers. If it did not return to Exegol, is it safe to assume that after the Battle of Exegol, it cruised around the galaxy and likely blew up other Resistance planets?  I've been researching Star Wars canon and websites, but I haven't found anything yet that sheds light on what happened to this Star Destroyer.


I'm not quite sure I can apply the Master Theorem to T(n) = T(3n/4) + T(n/6) + 5n. It is not in the normal form of T(n) = aT(n/b) + f(n). Is it possible to apply the MT to it? If not, can the recurrence be resolved without using Akra Bazzi?

$\displaystyle T(n) = T\left(3n\over4\right) + T\left(n\over6\right) + 5n$ is not in the proper form for the Master theorem so I can't really apply it. The only idea I had was changing the $\displaystyle T\left(n\over6\right)$ to $\displaystyle T\left(3n\over4\right)$ and then we would have $\displaystyle T(n) = 2T\left(3n\over4\right) + 5n$ for the MT to apply.   I would thereby bound the function by another function. Probably not a good solution and possibly wrong. Is there a better way to solve this?


I would like to create a trigger to export Latex file on the tool bar to replace Update trigger. Anyone knows the commands behind this Export>LaTeX(XeTeX)？Or where could I find the command?  Thanks in advance

I'm using LyX for technical documentation and want to automate the process of creating PDF files.  Within LyX, I can simply click the button "View PDF (XeTeX)", and LyX performs the whole build process for me: it creates a .tex file, does some bibliography magic, and uses XeTeX to create the final PDF file.  What I'm looking for is a way to call LyX from the command line and get the same result. So far, I've only managed to generate a plain .tex file (using --export-to xetex). However, when I run xelatex on the generated file, it keeps showing errors that don't occur when building using LyX. Is there a way to get LyX to do the work?  My system: Windows 7 64bit, LyX 2.1.0


I have a laptop that can obviously be inside or outside of my home network at times. When I need to SSH into a machine inside of my network, the connection is fairly straightforward:  localhost $ ssh machinelearning   When I'm trying to access the machine from outside of my network, I then need to connect to my router, then SSH from there:  localhost $ ssh router.mytotallyuniquedomain.com router $ ssh machinelearning   I remember there being a shortcut for doing the latter command in ~/.ssh/config, but at the moment I can't remember what it is.  Is there a way for me to supply multiple hostnames or types of connections so that when I do this:  $ ssh machinelearning   SSH will first attempt to connect to the machinelearning host in the local network and then attempt to tunnel in through router.mytotallyuniquedomain.com, all without me having to type out the long hostname?

I have three Computers.  PC1 and PC2 is on a private LAN, where PC1 is known to PC2 as 192.168.0.2  PC2 and PC3 is on a another  LAN, where PC2 is known to PC3 as 192.168.123.101  How can I connect to PC1 from PC3 with SSH.  Is there something like:  ssh user@192.168.0.2 -via user@192.168.123.101


I'm trying to understand what the noexec flag actually accomplishes. Does it prevent all executions originating from that file system? Or is it only ones that aren't in the bin folder?  In addition, let's say I manage to set exec as the default flag for all drives. Is there actually a risk that I could plug in a USB and it would automatically execute malicious code? Is this what noexec exists for, or is it only there to prevent users from doing stupid things with random executables?  This is different from the suggested duplicate as the duplicate does not explain whether there are security vulnerabilities associated with this practice.

I am trying to understand the NOEXEC flag when mounting.  I am having an execution issue within the /tmp directory on someone elses machine that I cannot access atm where the /tmp directory is mounted onto a different drive than '/' and NOEXEC is present.  I wanted to try and recreate this scenario on my machine, but I do not have a second hard drive.  I tried doing the following command:  mount --bind /test1 /test2   I then removed the bind flag and added NOEXEC in /etc/fstab.  Then, I created a file in /test2 called test.sh where it just echos 'hello world'.  I try and run it and it said 'permission denied'.  I then ran chmod 777 test.sh and was able to execute the file just fine.  I thought that the NOEXEC flag should not allow me to execute anything?  Is mount --bind /test1 /test2 not the same as mounting from a completely different physical drive? As in /test1 and /test2 are on different drives?


You know (hypothetical) Larry, the CEO's third cousin, who was hired on an important and well paid position even though he totally sucks at it, dragging the entire department down, but the CEO keeps him and blames everything on lower level employees, reducing their pay and rerouting it to Larry?  Is there an idiom in English for this kind of situation?  To clarify, the idiom should reflect the actions of the CEO. In my native language there is an idiom, roughly translating to "keeping someone on the feeding lot" although I feel like the context is diminished in English, it sounds like fattening cattle, while the original context is "keep feeding someone who hasn't earned or deserved it" but even more pronounced, not simply one who hasn't deserved it, but someone who actually doesn't deserve it.

I've heard a non-native English speaker use the expression "in this place, having a long arm to scratch someone else's back is more important than having a long résumé", conveying the idea of favoritism in a place influencing the promotion of people within. I would like to know if there is an equivalent in English to such expression.


From the point of view of performance / safety, it is better to use PDO or mysqli for queries with bind?

In our place we're split between using mysqli and PDO for stuff like prepared statements and transaction support. Some projects use one, some the other. There is little realistic likelihood of us ever moving to another RDBMS.  I prefer PDO for the single reason that it allows named parameters for prepared statements, and as far as I am aware mysqli does not.  Are there any other pros and cons to choosing one over the other as a standard as we consolidate our projects to use just one approach?


I was given a question like the following:     Let $A = \Bbb Z$, $B = [-1,\pi]$ , $C=(2,7)$. List all Elements of $A \cap (B^c \cap C)$.   I do not really understand how to got about this problem. I understand $\cap$ means intersection, but I have trouble reading the question; for instance, why place brackets between $B^c \cap C$?

After working it out on a number line, I got: $\{4, 5, 6\}$.  As it stands, the expression contains the integers that do not belong to the set $B$ that cross into $C$. This would result in $4, 5, 6$. Number $7$ would not be included because of the soft brackets surrounding $C = (2, 7)$. Is this correct?


If i update ubuntu from 13.04 to 13.10,  It will delete all the installed softwares..?  It will delete any of my data..?  I'm totally new to ubuntu.

How can I safely upgrade an Ubuntu installation from one release to another? What should I do before upgrading to ensure it goes smoothly, and is there any clean-up I need to do afterwards?  In particular, do I need to do anything special if I am using packages from PPAs, if I have a graphics card that needs drivers, or if I'm running a custom Linux kernel?  This is a general question , but as example we take Ubuntu 12.04 and Ubuntu 12.10


I posted yesterday about attempting a DIY to fix a snapped off USB Flash Drive.  So far, I've identified where I will solder the wires (thank you Micheal) on the PCB. I would just like clarification on what my wires are because none of my wires are black or white.  On top of that, the yellow leftmost wire is thinner than the rest. Why is that?  I'm thinking    red is red: +5V green is green: Data + yellow is white: Data - ? gray is black: GND ?   Image description: This is an iPhone USB Lightning cable with its internal wiring revealed. From left to right, the color are yellow, green, red, gray and I'm assuming the others are strips of a layer of casing.

I plan to solder the wiring from a cable with the USB end onto my USB flash drive.   I'm just not sure where to solder the wires…  This PCB is different from the DIY I've seen online.


In my MySQL database, phone in a VARCHAR. Then, I import this to a pandas dataframe. Here's my data:  data5  id   phone 1     +62634783472 2       0834838483 3              +62   What I want is convert +62 to 0, expected output would be like this  id   phone 1       0634783472 2       0834838483 3                0   I already try two thing, there are  data5['phone'] = data5['phone'].str.replace('+62', '0')  data5['phone'] = data5['phone'].replace(to_replace='+62', value='0', regex=True)   And the result is:  error: nothing to repeat at position 0   What is I miss?

I am tired of always trying to guess, if I should escape special characters like '()[]{}|' etc. when using many implementations of regexps.  It is different with, for example, Python, sed, grep, awk, Perl, rename, Apache, find and so on. Is there any rule set which tells when I should, and when I should not, escape special characters? Does it depend on the regexp type, like PCRE, POSIX or extended regexps?


I'm using the natbib package and have a sentence like this:     Smith's (2000) argument is widely accepted.   If I use \citet{smith2000}'s, this will lead to "Smith (2000)'s argument...".  Is there any way to get the desired genitive-s directly behind the name?  Here's my preamble:  \documentclass[paper=a4, fontsize=11pt]{scrartcl}  \usepackage[T1]{fontenc} % Use 8-bit encoding that has 256 glyphs \usepackage{longtable} %Muss vor arydslin stehen! \usepackage{arydshln} \usepackage[ngerman, english]{babel} % English language/hyphenation \usepackage[utf8]{inputenc} \usepackage{amsmath,amsfonts,amsthm} % Math packages \usepackage{arydshln} \usepackage[]{float} \usepackage[authoryear,round,longnamesfirst]{natbib} \bibliographystyle{plainnat}   Thanks for any hints!

I am using the Harvard package and a Journal of Finance bst file (downloaded from the ) in a LaTeX document. Here's my code:  \documentclass{report} \usepackage{harvard}  \begin{document} Citation one from \citeasnoun{Kozhan}, and also citation two from \citeasnoun{Kozhan}.  \bibliographystyle{jf} \bibliography{references}  \end{document}   With sample references.bib file:  @inproceedings{Kozhan,   title={The Skew Risk Premium in Index Option Prices},   author={Kozhan, R. and Neuberger, A. and Schneider, P.},   booktitle={AFA 2011 Denver Meetings Paper},   year={2011} }   This prints as:     Citation one from Kozhan, Neuberger, and Schneider (2011), and also citation two from Kozhan, Neuberger, and Schneider (2011).   I would rather have it as      Citation one from Kozhan, Neuberger, and Schneider (2011), and also citation two from Kozhan et al. (2011).   The guide on the Harvard citation styles (http://tex.loria.fr/bibdex/harvard.pdf) says:      [...] where there are more than two authors, all authors are   listed in the first citation and in subsequent citations just the first   author's name followed by `et al.' is used.   However, as can be seen by the example above, this does not seem to be the case. Why? Finally, how can I hyperlink my citations to the relevant entry in the references section?


Good day. I had to cut a piece of drywall on the ceiling to run some electrical. I used the same drywall patch (that I cut out) to repair the hole in the ceiling. I used mesh tape and joint compound (USG Plus3) to repair the hole. Since the drywall is not new (had paint on it), do I need to primer the patch or can I just paint over it? If I should primer, what would be the best primer for my situation?

I am in the process of painting my room. I have some big patches on the drywall. I am yet to begin painting that wall. Before i start i wanted to take advice. Is there anything i need to do with those patches so that after paint they are not visible?  Do i need to take special care of it?


Why are activation functions needed in neural networks? I know that it is to capture "non-linearities", but I have never been able to find a proper down-to-earth explanation. In particular, I am curious about the ReLU function as it is quite effective, but seems like such a simple function. How does that capture non-linearities?

When used as an activation function in deep neural networks The ReLU function outperforms other non-linear functions like tanh or sigmoid . In my understanding the whole purpose of an activation function is to let the weighted inputs to a neuron interact non-linearly. For example, when using $sin(z)$ as the activation, the output of a two input neuron would be:  $$ sin(w_0+w_1*x_1+w_2*x_2) $$   which would approximate the function  $$  (w_0+w_1*x_1+w_2*x_2) - {(w_0+w_1*x_1+w_2*x_2)^3 \over 6} + {(w_0+w_1*x_1+w_2*x_2)^5 \over 120} $$  and contain all kinds of combinations of different powers of the features  $x_1$ and $x_2$.   Although the ReLU is also technically a non-linear function, I don't see how it can produce non-linear terms like the $sin(), tanh()$ and other activations do.  Edit: Although my question is similar to , I'd like to know how even a cascade of ReLUs are able to approximate such non-linear terms.


How many times must you roll a die to be within $99\%$ confidence that it is fair? What if you were to use a die with more sides?

Roughly how many times do I need to roll a 6-sided die to feel confident that it's giving "fair" results? What about a 10-sided or 20-sided die?  Note that I will be actually manually rolling physical dice, this isn't just a textbook exercise. I'd like to minimize how long it takes me to perform this experiment with each die :)   I know this depends on my expected "confidence level" (95%? 99%?) If I choose a 95% confidence, for example, does that imply that 1 out of 20 fair dice will fail this test? Or that a single fair dice would fail the test 1 out of 20 times? If so, that sounds fairly high.   Are there standard techniques for doing this kind of a test?  Edit: It is beyond the scope of the math-focused question I've asked here, but I've explained more about the overall testing scenario over on the stats site here:


I currently have a base raster layer from OSM Standard used in my project. In the regular editing platform for QGIS, the place identifiers for cities are easily readable.    However, once I enter layout mode to prepare the map, the names become small and unreadable. I think this has something to do with the resampling but I'm not certain how to adjust it.    How can I modify the raster layer in layout mode so the place identifiers can be read, like in the editing mode?  I'm reposting this because the previous question I was directed to had no definitive answer. The recommendation to change the dpi to 96 severely limits the height/width attributes of the exported map as an image. Also,  did not work. In addition the recommendation to download another program and to modify an XML file in the new program's repository is overly convoluted.

For QGIS 2.2.0-Valmiera, how does one increase the label size of OpenStreetMap layer or any other basemap layer?  Presently the labels are way too small to read.  For example, I find that for the same zoom level of a map in www.openstreetmap.com vs the same map in QGIS2.2, the map in QGIS2.2 has labels much smaller than the one from www.openstreetmap.com.  For illustration, click here:


Is the punctuation of generational suffixes (e.g. "Jr.", "Sr.") dropped when they occur at the end of a sentence?  For instance,     I liked Gerald Rudolph Ford Jr.   The obvious answer seems to be yes, since having two periods back-to-back seems incorrect. If that is the case, however, it seems strange because there appears to be "information loss" in that the shortening of the generation suffix and the end of the sentence both share the same punctuation.

Example:     It's all about apples, oranges, bananas, etc.   VS.     It's all about apples, oranges, bananas, etc..   Update  What happens if the abbreviation is inside parentheses, do you place a dot after and before the closing parenthesis?     It's all about fruit (apples, bananas, etc.).


My problem is exactly the same as   I tried the solution:  sudo apt-get update sudo apt-get autoclean sudo apt-get clean sudo apt-get autoremove sudo dpkg --remove -force --force-remove-reinstreq pidgin   But on doing the final command I get this response:  dpkg: error: conflicting actions -f (--field) and -r (--remove)  Type dpkg --help for help about installing and deinstalling packages [*]; Use `dselect' or `aptitude' for user-friendly package management; Type dpkg -Dhelp for a list of dpkg debug flag values; Type dpkg --force-help for a list of forcing options; Type dpkg-deb --help for help about manipulating *.deb files;   For reference: After following the above process, I get the following output whatever I try to install:  $ sudo apt-get install python  Reading package lists... Done Building dependency tree        Reading state information... Done python is already the newest version. You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies:  pidgin : Depends: pidgin-data (< 1:2.7.11-z) but 1:2.10.3-0ubuntu1.5 is to be installed       Depends: perlapi-5.10.1 but it is not installable  pidgin-libnotify : Depends: libindicate-gtk2 (>= 0.2.2) but it is not installable                 Depends: libnotify1 (>= 0.5.0) but it is not installable                 Depends: libnotify1-gtk2.10 but it is not installable E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).   As suggested I tried   $ sudo dpkg --remove --force-remove-reinstreq pidgin dpkg: warning: ignoring request to remove pidgin, only the config files of which are on the system. Use --purge to remove them too.   Then I also tried-  sudo dpkg --purge --force-remove-reinstreq pidgin   I also tried:  $ sudo apt-get -f install Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following extra packages will be installed:   pidgin pidgin-libnotify Suggested packages:   gnome-panel kdebase-workspace-bin docker The following NEW packages will be installed:   pidgin The following packages will be upgraded:   pidgin-libnotify 1 upgraded, 1 newly installed, 0 to remove and 78 not upgraded. 1 not fully installed or removed. Need to get 0 B/710 kB of archives. After this operation, 2,205 kB of additional disk space will be used. Do you want to continue [Y/n]?  Selecting previously unselected package pidgin. (Reading database ... 359576 files and directories currently installed.) Unpacking pidgin (from .../pidgin_1%3a2.10.3-0ubuntu1.5_i386.deb) ... Processing triggers for bamfdaemon ... Rebuilding /usr/share/applications/bamf.index... Processing triggers for desktop-file-utils ... Processing triggers for gnome-menus ... Processing triggers for gconf2 ... Processing triggers for man-db ... Setting up pidgin (1:2.10.3-0ubuntu1.5) ... dpkg: dependency problems prevent configuration of pidgin-libnotify:  pidgin-libnotify depends on libindicate-gtk2 (>= 0.2.2); however: Package libindicate-gtk2 is not installed.  pidgin-libnotify depends on libnotify1 (>= 0.5.0); however:   Package libnotify1 is not installed.  pidgin-libnotify depends on libnotify1-gtk2.10; however:   Package libnotify1-gtk2.10 is not installed. dpkg: error processing pidgin-libnotify (--configure):  dependency problems - leaving unconfigured No apport report written because the error message indicates its a followup error from a previous failure.                       Errors were encountered while processing:  pidgin-libnotify E: Sub-process /usr/bin/dpkg returned an error code (1)

I recently installed Pidgin and tried to install pidgin-facebookchat. Ubuntu software center now says that pidgin is corrupt so I press repair but nothing gets fixed. I've tried sudo apt-get purge pidgin but I get this error:  Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies:  pidgin-data : Breaks: pidgin-facebookchat (< 1.69-2) but 1.69 is to be installed  pidgin-libnotify : Depends: pidgin (< 1:3.0) but it is not going to be installed                     Depends: pidgin (>= 1:2.10) but it is not going to be installed E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).   And sudo apt-get -f install results in this error  Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following packages were automatically installed and are no longer required:   language-pack-kde-zh-hans-base firefox-locale-zh-hans language-pack-kde-en kde-l10n-engb   language-pack-zh-hans-base kde-l10n-zhcn language-pack-zh-hans language-pack-kde-zh-hans   language-pack-kde-en-base Use 'apt-get autoremove' to remove them. The following extra packages will be installed:   pidgin-facebookchat The following packages will be upgraded:   pidgin-facebookchat 1 upgraded, 0 newly installed, 0 to remove and 31 not upgraded. 1 not fully installed or removed. Need to get 0 B/39.8 kB of archives. After this operation, 139 kB of additional disk space will be used. Do you want to continue [Y/n]? y dpkg: warning: there's no installed package matching pidgin-facebookchat:amd64   How can I uninstall Pidgin from my computer?, It is also blocking other applications from being installed.


Let $A_1, A_2, A_3,\ldots$ be pairwise disjoint denumerable sets.  Prove that $$\bigcup_{i=1}^\infty A_i\text{ is denumerable.}$$  This question comes from exercise $10.11$ of Mathematical Proofs: A Transition to Advanced Mathematics (Second Edition) by chartrand, polimeni, and zhang. I'm using this book for self study. I used induction in this  attempt. Sorry for the messy handwriting. I figured that the natural numbers were equivalent to integers from 1 to infinity, but a buddy pointed out that infinity was not an element of the natural numbers, so induction might not be possible. So, was it possible to use induction on this problem? Or should I just redo the proof by constructing a table of the denumerable sets and coming up with some diagonal arrows to order them like my book suggests.

The following is a question I'm interested in solving:    The idea is to solve it without using AC. As @Asaf Karagila pointed out in the comment section:  "Even if $\kappa$ is an infinite cardinal, you can't assume that $\kappa \geq \omega$ without using AC".  I am still trying to think this through: My reasoning being, that as $\kappa > n \forall n \in \omega$, then $\kappa \geq \sup\{n:n\in \omega\}=\omega$ as $\omega$ is a limit ordinal.  Where does my reasoning fail? And also, a detailed solution would be very appreciated.


I am running some Kubuntu 18.04 systems. I would like to to install a remote access software on these systems that allows accessing the systems from other Linux systems.  Does a free software exist that allows desktop sharing AND terminal server operation? I.e. a software that can do both:   Run before log-in, allowing to start a new desktop session on a computer where the specified user has not logged-in and has no active desktop session running.  Share an existing desktop session if the specified user already is logged in.

I know Ubuntu comes with a "Remote Desktop" option that appears to be a straightforward VNC server, and I'm trying to understand the alternatives. Here are the possibilities I've heard about so far:   VNC  VNC + SSH Tunnelling NX Server, free edition FreeNX NeatX X2Go X11 Forwarding over SSH xrdp    I'm coming at this from a Windows user's perspective: To the best of my experience, RDP (aka Terminal Services) is a reasonably secure (barring mitm/server spoofing), efficient desktop sharing protocol with well-supported clients, that can be exposed to the internet when necessary without major fears of intrusion. To the best of my knowledge straight VNC is none of those things, which is where I get confused - why wouldn't a better desktop sharing technology be developed or used in the open-source world? I know VNC can be wrapped with SSH, but that seems beyond the reach of a casual user. X11 forwarding over SSH may be more or less efficient, I have no idea, but is definitely even more complicated, and doesn't (as far as I know) give you access to already-running stuff (no desktop sharing as such, just remote application running).  So, I'd like any feedback/preferences amongst these or any other "Free" desktop sharing options, using these criteria and/or any others:   Security (esp. for access across internet) Efficiency (bandwidth usage, responsiveness, etc) Free-ness, as in Speech (not sure where RDP or FreeNX lie for this) Free-ness, as in Beer (are there any commercial solutions with usable dependable free offerings?) Ease of use (server and client side) Cross-OS Client availability Cross-OS Server availability Support for independent sessions and shared (and/or "Console") sessions Ongoing support/maintenance/development   Thanks!


I have some values from a JSON ARRAY. The values are Value1,Value2,Value3 and I have a checkbox in HTML with an ID the same as the Value.    I want to auto-check the checkbox which has the value from the JSON Array.  I tried to do this with below code:  var OtherPay = response.OtherPay; var benefit = OtherPay.split(","); var sum = benefit.length;  for (var i = 0; i < sum; i++) {           $('#'+benefit[i]).attr('checked',true); }

I'd like to do something like this to tick a checkbox using jQuery:  $(".myCheckBox").checked(true);   or  $(".myCheckBox").selected(true);   Does such a thing exist?


What happens if the team receiving the kickoff in overtime drives the ball for almost 10 minutes (unlikely but possible) and then kicks a field goal as the 10 minutes run out? Do they win?

Under the NFL's current "modified sudden death" overtime rules, if the first team scores a field goal, the second team is entitled to one more possession.  What happens if the clock runs out during that possession?  Suppose the score is tied 20-20 at the end of the 4th quarter. Team A wins the overtime coin toss and receives the kickoff to begin overtime.  After a long slow drive, Team A scores a field goal to make the score 23-20.  Now they kick off to Team B.  Team B is not able to score, and the overtime period ends with Team B still in possession.  What happens?   is not very explicit on this point.  Article 4 (a) says:     There shall be a maximum of one 15-minute period, even if the second team has not had an opportunity to possess the ball or if its initial possession has not ended. If the score is tied at the end of the period, the game shall result in a tie.   I think this means that Team A wins, 23-20, but I am not completely sure.  Has this ever happened in a regular-season NFL game?


I have created an Android App which opens a Map Fragment and is to create 2 markers: Marker 1 is the current location (which i believe may be the cause of the problem) Marker 2 which gets the coords(LatLng) passed from a previous Activity My problem is that when I run the app for the first time it crashes ... stops responding I have made sure all the permissions and manifest file is correct. But i have made the following observation : After the app crashes if i open Google Maps close everything and run the app again it works fine. The following error message is generated:  2020-07-16 09:51:16.363 3833-3833/com.notbytes.barcodereader E/AndroidRuntime: FATAL EXCEPTION: main Process: com.notbytes.barcodereader, PID: 3833 java.lang.NullPointerException: Attempt to invoke virtual method 'double android.location.Location.getLatitude()' on a null object reference at com.notbytes.barcodereader.MainActivity2$4.onSuccess(MainActivity2.java:197) at com.notbytes.barcodereader.MainActivity2$4.onSuccess(MainActivity2.java:192) at com.google.android.gms.tasks.zzn.run(Unknown Source) at android.os.Handler.handleCallback(Handler.java:751) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:154) at android.app.ActivityThread.main(ActivityThread.java:6077) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)  Any help or assistance will be greatly appreciated. TIA

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?


How can I create a blind footnote such as the one in the picture below?    By blind I mean that there is no number in the text, or in the footnote. I would like to have this footnote on the bottom of the first page of my document and all the other footnotes in the document should be unaltered.

In one section of a document I used   \let\thefootnote\relax\footnote{}   to have a footnote without number.   The problem is that it propagates through the whole document then and all footnotes appear to have no index.   How can I restrict the influence of this command to one particular footnote?  Update: I use unnumbered footnotes at the beginning of the chapter to specify, for instance, the version of software used throughout the chapter. It is common to do it like that in the community I am working.


When I scroll I get screen tearing, which ends up being a line that runs almost perfectly horizontally from the top-left to bottom-right corners of my screen that distorts whatever flows through it.  Has anyone encountered this before?

I have both Ubuntu 14.04 and Xubuntu 16.04 installed on one of my older desktops.  While both work fine, I experience screen tearing while dragging windows around in Xubuntu. However, I do not experience it on Ubuntu.  It is using the motherboard's built-in AMD graphics chip.  Note: This exact situation also holds true for my main desktop with a GTX650 graphics card...    At this point, I'm thinking it has something to do with Untiy being a 3D DE, and XFCE being a 2D DE...


Sorry for too many duplicate questions about this. But I don't think any of the answers to these kind of question has the solution for me.  As some users might have asked, how to set root login password when I never set it at installation?  I'm new to ubuntu, and although I used it mainly just for browsing and writing documents, I never use it beyond the standard user wall. Now I'm going to use it to learn develop ruby. My friend helps me over email with the terminal commands sequence needed to set up ruby and rails and whatsoever needed on my ubuntu.  But when I run the first command apt-get update, the OS tells me that it can't lock something something, and finally hinted "are you a root?" Just FYI, this ubuntu is a clean installation on virtual machine, and I just set one account name with one password at the installation. I never get asked about a root password.  I googled about how to run a command as root, and I found that I need to use the sudo command. But when I add the sudo prefix before the apt-get update command, I get asked for root password. I used my first and only account password, and it didn't work.  from what I've read on the internet, I get this conclusion and confusion:   the first user you created on the installation IS a default admin. -- but why I can't use administrator command, and have to requiring sudo? can't I just make my account at the same level as root account? you need to go into recovery mode to reset the root password. -- but the recovery mode is hard to access using virtual machine boot (pressing shift at just THE right time). is there any other way to change the root password?   Thank you for your helps.

When I install Ubuntu, it never shows an option to set a password, yet there is a password when trying to log in to the admin account and when I try to install packages. I can't change the password in Root because when I try to it says "Authentication manipulation token error". When I try to fix the shadow password thing in root it says access denied.


We know that quantum mechanics requires self-adjoint operators, not only symmetric. Can we say that this follows ONLY from the two following axioms of quantum mechanics, namely that    each observable $a$ corresponds to a linear operator $A$    and    an expectation value of a measurement of $a$ must be real   ?  I thought these two imply only the need for a Hermitian (i.e. symmetric) operators (because a linear Hermitian operator has real eigenvalues)  and that the need for self-adjointness was somehow connected to an additional requirement such as unitarity of the time-evolution operator. What is the missing piece?   (I know how the two terms are defined, e.g. .)

A symmetric operator has only real eigenvalues and different eigenvectors corresponding to different eigenvalues are orthogonal.   These are exactly what we want for a physical observable. I think this is the all required.   So why is quantum mechanics not satisfied with symmetric operators, but wants more?


I have a problem with an app that i try to run. I have a listview which is made from names that i add in an edittext of a class. When there are no items, when i move to listview the app crashes and i get that error:  java.lang.NullPointerException: Attempt to invoke interface method int java.util.List.size() on a null object reference  While I have one or more items in listview I can see them without crashes or errors. Can you help me please? Below is my code.  public class ListAdapter extends BaseAdapter { Context context; List<Student> valueList;  public ListAdapter(List<Student> listValue, Context context) {     this.context = context;     this.valueList = listValue; }  @Override public int getCount() {     return this.valueList.size(); }  @Override public Object getItem(int position) {     return this.valueList.get(position); }  @Override public long getItemId(int position) {     return position; }  @Override public View getView(int position, View convertView, ViewGroup parent) {     ViewItem viewItem;     convertView = null;      if(convertView == null)     {          viewItem = new ViewItem();          LayoutInflater layoutInfiater = (LayoutInflater)this.context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);          convertView = layoutInfiater.inflate(R.layout.listviewitem, null);          viewItem.TextViewStudentName = (TextView)convertView.findViewById(R.id.textView1);          convertView.setTag(viewItem);      }     else     {         viewItem = (ViewItem) convertView.getTag();     }      viewItem.TextViewStudentName.setText(valueList.get(position).StudentName);       return convertView;}} class ViewItem{TextView TextViewStudentName;}   The error is located in command return this.valueList.size();. If you need i can post the other classes of my code too. Thank you in advance!


I am developing XNA game like following screenshot.    I created my 3D objects and camera so I have models. But how can I implement scrolling road in XNA?

I want to create the illusion that a man is running down a long road i.e. this pic    If you have played Temple Run on the iPhone, it's the same principle, but instead of a temple it's a normal road.   I want to know how this is implemented. For example, do I just repeat this road image in a loop?


The fundamental theorem of cyclic groups says that a for a cyclic group $G$ where $|G|=n$, for every divisor $d$ of $n$, there is a unique subgroup of $G$ with order $d$. My question is that whether these are the only subgroups of any cyclic groups? In other words, is it true that $G$ contains exactly $m$ subgroups where $m$ is the number of divisors of $|G|$?

My attempt  Note- Addition is under $mod$ $d$  Let $G = (a^0,a^1,a^2.....a^{n-1})$  $n=kd$  Let $H_d = (a^{0k},a^{1k},a^{2k}......a^{{(d-1)}k})$  For $a^{z_1k},a^{z_2k} \in H_d$  $a^{z_1k}a^{z_2k} = a^{{(z_1+z_2)}k} \in H_d$  $H_d$ is closed  For $a^{zk} \in H_d$  $a^{zk} (a^{zk})^{-1}=a^0$  $(a^{zk})^{-1} = (a^{-1})^{zk}$  Since $a^{-1}$ is $a^{n-1}$ we can rewrite it as   $(a^{zk})^{-1} = (a^{n-1})^{zk}=a^{z(n-1)k} \in H_d$  Since $(a^{zk})^{-1} \in H_d$ and $H_d$ is closed, $H_d$ is a subgroup.  I can easily prove the 3rd part by using Lagrange's theorem.  I have no idea how to prove that only $1$ subgroup of order $d$ exists. Maybe by proving that the elements of the $2$ groups have to be the same?  I would really appreciate if someone could verify my proof so far and give some hints to complete the proof.


Here's an excerpt from Schwartz's QFT text, section 8.2, that's always totally confused me.     A natural guess for the Lagrangian of a spin 1 field is   $$\mathcal{L} = - \frac12 \partial_\nu A_\mu \partial_\nu A_\mu + \frac12 m^2 A_\mu A_\mu.$$   Then the equations of motion are   $$(\Box + m^2) A_\mu = 0.$$   In fact, this Lagrangian is not the Lagrangian for a massive spin-1 field, but the Lagrangian for four massive scalar fields, $A_0$ through $A_3$. You might wonder how we know if $A_\mu$ transforms as a vector or four scalars. As a very general statement, we do not get to impose symmetries on a theory. We just pick the Lagrangian, and let the theory go.   I find this passage incredibly confusing. First, how is it apparent that there are four massive scalar fields, when it looks like the equation of motion works either way?  Second, Schwartz seems to be saying that the Lagrangian determines how the fields inside it transform, which seems exactly backward to me. Don't we first postulate that fields exists with certain transformation properties, then write down scalar Lagrangians for them? That's exactly how we construct the Dirac spinor, for instance -- we write down how it transforms, and only afterward write down the Dirac Lagrangian.

Given the Lagrangian density of a theory, are the representations on which the various fields transform uniquely determined? For example, given the  for a  $$ \mathscr{L} = \frac{1}{2} \partial_\mu \varphi \partial^\mu \varphi - \frac{1}{2} m^2 \varphi^2 \tag{1}$$ with $(+,-,-,-)$ Minkowski sign convention, is $\varphi$ somehow constrained to be a scalar, by the sole fact that it appears in this particular form in the Lagrangian? As another example: consider the Lagrangian $$ \mathscr{L}_{1} = -\frac{1}{2} \partial_\nu A_\mu \partial^\nu A^\mu + \frac{1}{2} m^2 A_\mu A^\mu,\tag{2}$$ which can also be cast in the form $$ \mathscr{L}_{1} = \left( \frac{1}{2} \partial_\mu A^i \partial^\mu A^i - \frac{1}{2} m^2 A^i A^i \right) - \left( \frac{1}{2} \partial_\mu A^0 \partial^\mu A^0 - \frac{1}{2} m^2 A^0 A^0 \right). \tag{3}$$ I've heard$^{[1]}$ that this is the Lagrangian for four massive scalar fields and not that for a massive spin-1 field. Why is that? I understand that it produces a  equation for each component of the field: $$ ( \square + m^2 ) A^\mu = 0, \tag{4}$$ but why does this prevent me from considering $A^\mu$ a spin-1 massive field?  [1]: From Matthew D. Schwartz's , p.114:  A natural guess for the Lagrangian for a massive spin-1 field is $$ \mathcal{L} = - \frac{1}{2} \partial_\nu A_\mu \partial_\nu A_\mu + \frac{1}{2} m^2 A_\mu^2,$$ where $A_\mu^2 = A_\mu A^\mu$. Then the equations of motion are $$ ( \square + m^2) A_\mu = 0,$$ which has four propagating modes. In fact, this Lagrangian is not the Lagrangian for a amassive spin-1 field, but the Lagrangian for four massive scalar fields, $A_0, A_1, A_2$ and $A_3$. That is, we have reduced $4 = 1 \oplus 1 \oplus 1 \oplus 1$, which is not what we wanted.


Let $V$ be a vector space over a field $F$, and $U,W_1,W_2$ three subspaces of $V$, with  $$U⊆W_1∪W_2$$  Prove that $U⊆W_1$ or $U⊆W_2$.

I'm having a difficult time understanding this statement. Can someone please explain with a concrete example?


I have run into the awkward situation, where I've posted a programming question, and received an answer, that I cannot apply due to project guidelines.  The account under which I posted the question identifies me, or at least for people knowing me, the user name would make it clear. Hence I don't feel comfortable saying "can't accept your answer, because of internal reasons" for fear of it reflecting badly on the company, or annoying my superior.  Now I am a bit stumped how to proceed. I cannot meaningfully reply to the answer, so I'd prefer to rephrase or delete and repost it. Rephrasing would however invalidate the given answer, and deleting answered questions is discouraged.  What is the best practice to proceed in such cases?

Here's my issue, mostly with privacy:   I connected all my SE accounts long ago but recent events have made it much easier to jump from my profile here to my profile elsewhere. I have questions on site A that I'd rather not be associated with my "identity" from site B. I have no way to delete a question on site A since it has been answered and I have no way to anonomize it for privacy concerns.   Is there a way to:   Delete the question Anonymize the question Unlink my account from site A?


I want to select PostgreSQL rows based on Date range. I tried this:  Date start; Date end;  ps = conn.prepareStatement("SELECT * FROM SCHEDULE WHERE START_DATE = ? AND END_DATE = ?");  ps.setDate(1, (java.sql.Date) start); ps.setDate(2, (java.sql.Date) end);   But I get   java.lang.ClassCastException: java.util.Date cannot be cast to java.sql.Date     at com.crm.web.schedule.Schedule$1.loadEvents(Schedule.java:62)   How I can properly select range of dates?

I am trying to use a  as input and then creating a query with it - so I need a .    I was surprised to find that it couldn't do the conversion implicitly or explicitly - but I don't even know how I would do this, as the Java API is still fairly new to me.


I have a downloaded object that I placed on the stage and textured. An object in the "Material Preview" and "Render" modes in the viewport is displayed, but upon final rendering, the object disappears. What could be the problem?

This is meant to solve this problem once and for all. What is every reason an object isn't showing up in a render or viewport in when using the cycles render engine?


Currently I have Windows and Ubuntu installed and dual boot is working fine.  However the dual boot is loading via GRUB, but I want it to load from Windows' bootloader as I want to enable bitlocker.  How can I hide grub and show Windows' bootloader when I press the power button?

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


Is is possible to make a PDF in Beamer such that notes are visible only on computer and not on the projector?

I really like the way Keynote and MS Office (and also OpenOffice & similar) support a presentation mode that displays the current slide, the next (and maybe previous) slide, the elapsed and current time, and also any notes attached to the slides on one screen and the presentation itself on the beamer/second screen.  It enables me to give good, professional presentations without having to know everything by heart (I suck at that).  I found a , but I am looking for alternatives, especially OS-independent would be great. Not having to create 3 different PDFs is a boon.  Any hints?


I'm marking up some text that includes "l" as a vector, so I'd like to be able to use a bold font. \mathbf{l} gives a straight up-and-down kind of l which looks like a 1 (one) or an I (capital "i"):    I don't want to use \ell because I don't want the loop and for some reason my system won't make the corresponding glyph bold for me.  What I'd like looks more like this:    What are my options?

To make Latin-letter variables bold I can use e.g. \mathbf{a}, but while putting Greek letters or symbols such as \nabla inside \mathbf doesn't cause any errors or warnings, it also doesn't do anything else.  What is the best way to make bold math symbols, in particular Greek letters and \nabla?


Why is the blog of Stack Exchange different on various posts? For instance, this blog post allows comments:   But this one doesn't:   Why not allow commenting in all blog entries?

The most recent  seems to have lost its comment section at the bottom. What happened to it?


An enemy creature is 10 feet away from the caster. Right next to the creature is another enemy or friendly creature. Can Lighting Lure pull the target creature through the other creature's space, and into the empty space next to the caster?

What blocks the "pull" from Thorn Whip?  Thorn Whip:  ...and if the creature is Large or smaller, you pull the creature up to 10 feet closer to you.  As a specific example, the druid pulls a creature that is 15 feet away, but right in front of the target (and between the target and the druid) is another creature.  Can the target be pulled through the other creature?  Does it matter if the other creature is an enemy or ally?  Does the other creature have any choice in the matter?