I am trying to teach myself C language. My transition from C has been rough so far. I am doing a problem from the Book "Intro to C language" and there is a problem that should read a line from the user and then ask the user for an int. My job was to find that particular word corresponding to the int.   Example     Hello World, How are you all doing. // This is the line being read      2 // the word to be printed to the console   Expected Output     World   Below is a snippet of my code that i think is giving me the bus error.   void corrspndToInt (char *theLine, int word, char *result ) {      int start;     int end;     int spaces = 1;     result = "";      //int i;      //search for the nth non-blank character      for(start = 0; start < strlen(theLine) && (spaces < word); start++ ) {          if( isspace ( theLine[ start ] ) ) {              spaces++;         } // end if      } // end for loop      //only need to continue if we haven't gone past the end of the string      if( start < strlen(theLine) ) {          //the next blank character is the end          for ( end = start; end < strlen(theLine) && ( !isspace ( theLine[ end ] ) ) ; end++ ) {          ;          } // end for loop          //we now have the word          result = strncpy ( result, theLine+start, end - start);        } // end if  }   This is how i am printing the result in main function.  printf("%s\n", result );   Now that i have been teaching C language to myself and through SO i learned that returning char arrays should not be done. There were two methods dynamic allocation using function malloc and there was another method which is the one i implemented in my code. I have checked my other method and there seems to be nothing wrong with that. The problem here is with this method as it is not getting the correct word.  I have been trying to debug my program but apparently Mac doesn't accept the gdb command. I have installed the command line tools and everything else but it still says      Command not found   Can anyone please guide me in the right direction here? I have been overthinking this problem from the last 1 hour now.

The following code receives seg fault on line 2:  char *str = "string"; str[0] = 'z';  // could be also written as *str = 'z' printf("%s\n", str);   While this works perfectly well:  char str[] = "string"; str[0] = 'z'; printf("%s\n", str);   Tested with MSVC and GCC.


If photons travel at the speed of light than due to relativity they must experience no time frame in which to be destroyed in the first place so they must be immortal which is silly. So, clearly I am misunderstanding something.

To an an external observer it appears that time has stopped for photon. But this relation is reflexive, so for an observer travelling with the photon it appears the universe has stopped everywhere.  Is this right?  Space also gets distorted parallel to the direction of motion, but not perpendicular to it.   Does this mean that for an observer travelling with a photon sees spacetime as a flat plane?  Note 1: I'm using language vividly not literally when I say a photon experiences space and time. Not that I'm against idealist or panpyschist interpretations of matter or energy come to that.  Note 2: Since it's been pointed out that an inertial frame can't be boosted into the frame of a photon and moreover there is no limiting behaviour here - no matter what frame you are boosted into, light will always appear to travel at c. Nevertheless, when an external observer watches a train chasing a photon by gradually increasing its speed, he will note that the train speed is approaching the speed of the photon (but will never match it) and when he looks at the clock inside the train he will not too that it is gradually slowing down (but never actually stops). Using this picture, we can attempt the thought experiment - if not one that can be carried out - of what a world looks like to a photon.


I once read a book about 40 years ago that was from the early 1950s.  The premise was a scientist working on a "Superbomb" (described as a Hydrogen bomb) in a rural American town/city. An atomic war breaks out and the city is hit.  The bomb doesn't destroy the town; instead the town is catapulted millions of years into the future where the Sun is a growing red giant star and humanity is long gone.  Aliens find the town and help the folk out somehow.

It starts with a town that was hit by a mysterious explosion which transports that town into a desert. The weather is cold and people burn coal but they soon run out and send out an expedition to look for signs of life - they navigate the desert for a couple of days and come across a glass dome covering a city. Apparently they have been transported far in the future.  And that's where I stopped reading and want to resume now. Don't remember the title or the author and it's at least 20 years old.


I have an MVC Application that asks the user for the Phone Number. There is a mask so it always looks like "(567) 222-0001.  When this phone number is saved in the database, it gets saved with these brackets and the hyphen. Instead, I would like to save it to the DB without the brackets and the hyphen i.e. a raw phone number. The application uses LINQ.  Any help is appreciated. Also, I am new to MVC, so I have a very rough idea where to look in the code.

Quick add on requirement in our project.  A field in our DB to hold a phone number is set to only allow 10 characters.  So, if I get passed "(913)-444-5555" or anything else, is there a quick way to run a string through some kind of special replace function that I can pass it a set of characters to allow?  Regex?


I am a beginner, making trees in Latex, but some of my nodes keep melting together.   They are not supposed to be linked in anyway, but I cannot find out what I am doing wrong.    Can anybody please help me?

I have been struggling a bit with TikZ and how to build trees. What I need now is some advice on how to improve the node placement. Right now I have these 2 trees:  \documentclass[a4paper,10pt]{article} \usepackage{tikz} \usetikzlibrary{positioning,shadows,arrows,trees,shapes,fit} \begin{document} \begin{tikzpicture} [font=\small, edge from parent fork down,  every node/.style={top color=white, bottom color=blue!25,  rectangle,rounded corners, minimum size=6mm, draw=blue!75, very thick, drop shadow, align=center}, edge from parent/.style={draw=blue!50,thick}, level 1/.style={sibling distance=6cm}, level 2/.style={sibling distance=2.5cm},  level 3/.style={sibling distance=2.5cm},  level distance=2cm, ]  \node {Paletizar} % root     child { node {Iniciar}          child { node {Detectar Pacote}}         child { node {Movimentar}}         }     child { node {Empacotar}         child { [sibling distance=15mm] node {Posicionar}             child { node {Pegar/Largar}}             child { node {Organizar}}             child { node {Movimentar}}             }         child { node {Agrupar}}         child { node {Padronizar}}         }     child { node {Finalizar}          child { node {Detectar estado\\da palete}}         child { node {Transmitir}} }; \end{tikzpicture}   \vspace{2cm}  \begin{tikzpicture} [font=\small, edge from parent fork down,      every node/.style={top color=white, bottom color=blue!25,      rectangle,rounded corners, minimum size=6mm, draw=blue!75,     very thick, drop shadow, align=center},     edge from parent/.style={draw=blue!50,thick},     level 1/.style={sibling distance=6cm},     level 2/.style={sibling distance=3cm},      level 3/.style={sibling distance=2cm},      level distance=2cm,     ]      \node {Paletizador} % root         child { node {Inicialização\\de sistema}              child { node {Sensor X}}             child { node {Acção Y}}             }         child { node {Sacos}             child { node {Linha/Coluna}                 child { node {Garra}}             child { node {Rodar Garra}}             child { node {Acção Y2}}             }         child { node {Euro Pallet}}         child { node {Disposição $xyz$}             child { node {$x=?$}}             child { node {$y=?$}}             child { node {$z=?$}}             }         }     child { node {Sistema de despacho}          child { node {Sensor de peso\\/contador}}         child { node {Tapete rolante\\de saída}} }; \end{tikzpicture}  \end{document}   So basically what I want is a way to edit the code I have so that everything is perceptible which basically means that I need specific sibling distances to each child. I have tried to add a sibling distance in the child nodes but maybe it was in the wrong place or something else because it didn't change anything. I also tried to use below and all its derivations but the results were even worse because of the size of the boxes.


My requirement is shown below by maps.  Map 1--My Map   Map 2--I required     I am using GeoServer v2.2(for publishing the map) and OpenLayers v2.11(to display the map). According to my client requirement I published one layer with name "3d Buildings" in GeoServer and given a 3D style.  I added this layer as WMS in OpenLayers.  Now its look like a 2.5D Map(refer "Map 1").  My Questions are;   In Geoserver   Look at the buildings in "Map 1" its showing flat roofs, But I need different shapes of roofs like the buildings in "Map 2". Or How can I load 3D models to a layer?   In Openlayers(2.11)   How can I rorate/flat map like google earth? Please see the "Map 2" which is in flat view. you can see sky also .In Google API they are using "map.setTilt(45)" to change the map angle. Like this any option is available in openlayers?. Or How can give Navigation Controls like in google earth? How Can I load 3D Models on map?   If these features are not available in GeoServer and OpenLayers, introduce me a new tool. Kindly help me.   Thanks

I would like to try to show a proposed building in a web-browser such that the user can interact with it in a way similar to google maps streetview. Is it possible to do this, in any platform?  I can produce the building format in any geospatial format known to humanity, but as far as I can tell, Google Streetview only allows points to be inserted using their API. I don't want to force users to download a plugin to view this (which is why I would prefer not to use the Google Earth plugin)[updating this point in response to comments].  One thought I had was to try to make a panorama using static images of the building in some other tool that would be scrollable to give the appearance that it was embedded in a map. I presume this would be against the terms of service of Google, but I'm mainly curious how this can be done.  I'm also open to using any paid service for this functionality, or considering any new technology such as ,  or perhaps a 3D javascript library such as


Anyone has any idea the estimated result(no need to be accurate) of $\sum \limits_{i=1}^{50} \frac{1}{2i-1}$? I think this problem is not hard but I don't have a generalized method to solve!  And I also remember this problem related to a very famous probability problem, any one has any idea? Thank you!

Mathematica tells me that $\sum\limits_{i=1}^n \frac1{2i-1}$ is equal to $\frac12 H_{n-1/2}+\log\,2$, where $H_n$ is a harmonic number.  Why is this true? Is there a general strategy for evaluating sums of the form $\sum\limits_{i=1}^n \frac1{ai+b}$?


I know I can go  to see my rank in a particular tag. But is there a way to see at what percent I am in?

The thing is, I think I'm doing OK. I haven't been on SO for that long, but I put in the time, I get the votes and answers and I am currently on . But the thing is, no matter how hard I try, I won't beat . ,  and I'm not going to get his face off of the user league.  But even though he does very well, he gets most his points answering jQuery questions and I'm a C# guy. I envision user leagues based on tags. I know, tags can be changed and it may not be trivial to define how someone scored on a tag. But if you'd for instance include a user in a tag league when 50% of his answers are to questions with a specific tag, it could very well be representative. And at last, I'll have a chance again. EDIT: OK, it's official, I'm blind. @Pekka answered that this already exists. However, is there a chance that this could look as nice as the normal user league, including the week, quarter and year score?


OS - Windows 7 (32-bit) Office Version - 2013 Standard  Whenever I right click on a blank space in a folder, I see option to create a New Folder / New Word Document etc, but am not able to see a New Excel Workbook option. How can I get the option?

When I right click anywhere I get an option to add a new file with a specified extension. I would like to add some custom files into this menu, so I can right click and create a new PHP file for instance.  How can I do this?


Did magical genes result from a slight change in the Human DNA? If so, who was(were) the first wizards? If they were pureblood magical wizards, how are the wizards today still pureblood, assuming that they may have bred with muggles?  Or was magic a sentient form that to earth from the heavens (other planets, species from wherever in the universe) and fuse with themselves with humans to create magical genes?  Did the magical gene distribute itself evenly among earth's population?

What is a wizard that makes them non-Muggle? Or, more directly, what ancestry does the witch/wizard gene follow? Is there a patriarchal wizard (or matriarchal witch) that Muggles have no part in? Elves perhaps? Stop reading here.  Purpose of the Question/History/Don't Read There seem to be solid consequences associated with being Muggle, or Muggle-related. A dominant theme in the novels is discrimination against the non-gifted race, but, when read into, the wizard bloodline doesn't appear all that well defined. JKR indicates that wizard-ness is genetic, or inherited:  "Muggle-borns will have a witch or wizard somewhere on their family tree, in some cases many, many generations back. The gene resurfaces in some unexpected places."  By the above, it stands that a family that produces a squib (non-magical born of magical parents) must be a half-blooded family in some way, since half-blooded only requires one non-magical ancestor. Of course, we are dealing in magic genetics. Any other form of genetics would make this inherited, seemingly recessive trait (or squibs couldn't exist), never appear at all. Unless they were XMen. If it is so important, what does the wizard-bloodline follow? Other Mythos In other literature a wizard can be nearly anything, but magical powers are typically inherited as well as learned. Merlin of the Arthurian Legend (also mentioned in HP) is Cambian, meaning he is born of demonic intervention; this explains his source of enchantment. Gandalf of Middle Earth is a Maiar, as are all Wizards of Middle Earth. Wizards in Harry Potter seem to follow a bloodline, and it has been mentioned (in the question Gabe linked) that genetics have a heavy play in it, meaning that squibs and parents of Muggle-born wizards should have identical genetics. This bloodline must come from somewhere. Magical Creatures In Harry Potter it is common for magical creatures to "mingle" with humans, these beings are typically somewhat magical. Elves have been described to have very strong magic, but are for some unreasonable reason subservient to humans. I may be mistaken, but believe it was hinted that elves and the wizarding lineage had intersected at one time. Maybe I'm imagining this. Genocidal Allusions Voldemort hates muggles, and half-bloods, and whatever else is non-wizard. The presence of this theme, suggests that this wizardly bloodline must be at least defined if the main antagonist is so obsessed with keeping that mysterious bloodline pure. Since Slytherin himself was said to be a supremacist (circa a really long time ago) it suggests that this bloodline should have existed long before he was around, especially if he founded a school with people he was not related to, but were also magical.


I bought a PS4 and it already had a PSN profile, so I created my own profile and used the original PSN profile to play online. Now the PlayStation Plus subscription is about to expire.   Instead of renewing the original profiles PS+ subscription, I want to purchase a new PS+ subscription for my new PSN profile.   The problem is I pre-ordered CoD: Black Ops 3 with original PSN profile and don't want to buy PS+ subscription for my profile if I won't be able play the game online.  I would renew original profiles PS+ subscription if I it meant I could still play the game on my own PSN profile.

Both my girlfriend and I play on the PS4 at home, so there are 2 profiles on PS4. When we set our profile in PS4, we set the console as the primary console.  Now we want to buy PSN Plus subscription, and I want to know if the same subscription can be used in both profiles, or  only in one.   In case the same subscription can be used in both profiles, how can we set it up? Or is automatic?


Let $D$ an integer such that it is not a perfect square in   $\mathbb{Z}$.       If $D \equiv 1$ mod $4$, the set $$T:= \{\left( \begin{matrix} a & b  \\ \frac{(D-1)b}{4} & a+b \\ \end{matrix} \right) : a, b \in  \mathbb{Z} \}$$ is a subring of $M_2(\mathbb{Z})$ which is isomorphic   with the ring $$O := \{a+b\frac{1+\sqrt{D}}{2}: a, b \in \mathbb{Z} \}$$   My problem is to find a such isomorphism. However, I find this relation : $$\det \left( \begin{matrix} a & b  \\ \frac{(D-1)b}{4} & a+b \\ \end{matrix} \right)$$ $$= a(a+b)-\frac{b^2(D-1)}{4}$$ $$= (a+b\frac{1+\sqrt{D}}{2})(a+b\frac{1-\sqrt{D}}{2})$$  and $D \equiv 1$ mod $4$ $\iff$ $(\frac{1+\sqrt{D}}{2})(\frac{1-\sqrt{D}}{2}) = -k$ for some $k \in \mathbb{Z}$  Does someone could give me a little hint to help me complete this problem?

Let $D$ be an integer such that it is not a perfect square in   $\mathbb{Z}$.       If $D \equiv 1$ mod $4$, the set $$T:= \left\{\left( \begin{matrix} a & b  \\ \frac{(D-1)b}{4} & a+b \\ \end{matrix} \right) : a, b \in  \mathbb{Z} \right\}$$ is a subring of $M_2(\mathbb{Z})$ which is isomorphic   to the ring $$O := \left\{a+b\frac{1+\sqrt{D}}{2}: a, b \in \mathbb{Z} \right\}.$$   My problem is to find an isomorphism. However, I find this relation : $$\det \left( \begin{matrix} a & b  \\ \frac{(D-1)b}{4} & a+b \\ \end{matrix} \right)$$ $$= a(a+b)-\frac{b^2(D-1)}{4}$$ $$= \left(a+b\frac{1+\sqrt{D}}{2}\right)\left(a+b\frac{1-\sqrt{D}}{2}\right)$$  and $D \equiv 1$ mod $4$ $\iff$ $\left(\frac{1+\sqrt{D}}{2}\right)\left(\frac{1-\sqrt{D}}{2}\right) = -k$ for some $k \in \mathbb{Z}$  Does someone could give me a little hint to help me complete this problem?


The Feynman Lectures on Physics probably constitute the most famous introductory physics textbook ever written.  The level of intuition it provides is hard to beat; I first started reading it in middle school, and a decade later I'm still finding new insights in it.  Yet when I recommend it to others, they often have sticker-shock.  It is a three-volume book, after all.    So is there any legal way to read the Feynman Lectures for free, on the Internet?

I'm trying to amass a list of physics books with open-source licenses, like Creative Commons, GPL, etc. The books can be about a particular field in physics or about physics  in general.  What are some freely available great physics books on the Internet? edit: I'm aware that there are tons of freely available lecture notes online. Still, it'd be nice to be able to know the best available free resources around.  As a starter:         Table of contents sorted by field (in alphabetical order):


I am trying to post an  to a question on Stack Overflow. I get this response     You need at least 10 reputation to post an image   What on earth does it mean, what do I need to do to post an image with my answer ?

I have previously tried asking questions as simply as possible but they have been blocked like in the following link    So owning up to my mistake I tried posting a detailed question but table tags are not available in here to format my sample dat ; so I went for images and alas it tells me that I need atleast a reputation of 10 to post images!   Please somebody help me to post my question.


I'd like to downgrade my Nexus 9 to android 4.X (KitKat). Is this possible? I'm not the pro doing something like that and I could not find something with google.  Can you help me please? Thank you

I installed the KitKat upgrade on my Nexus 7, but I am unhappy with it. Is it possible to roll back to an earlier version of Android (Jelly Bean)?


I had purchased eggs at the supermarket and i forgot them in the trunk of my car for for 3 days are they still okay to eat?

A friend of mine accidentally left a carton of eggs on her counter, unrefrigerated, for three days. The eggs had been previously refrigerated both at the store and at home. Now she's planning to do some more cooking which requires eggs, and is wondering if it's still safe to use them for baking. I believe she is planning on baking cookies with them, so they would be baked at fairly high temperatures for probably at least 10 minutes. Would this be safe, or are eggs left unrefrigerated for that long not safe for consumption?


I'm trying to link a pdf to a parcel (see image: ) where you click on one parcel and a specific pdf comes up and if you click on another then a different pdf comes up.   I've got it so far that if you click on a parcel it shows a pdf but the problem is that is shows the same pdf for every parcel!  Is there anyway I can assign it to just one parcel by lets say the objectid?  I'm having trouble setting the action so that it opens each parcel.

How to add hotlink to QGIS? I saw  but had some problem. I want to open network location like \\fileserver\filefolder\file1.excel but it ends with error.  Edit:     The network location is stored in a column of the table eg. URL column contains URL value for each attribute. Different row has different URL.


Given a sequence $u_{n}$ such that: $u_{n} \rightharpoonup 0$ in $L^{2}(\mathbb R^{n})$ & $A$ is a compact operator. The problem is to show that :  $Au_{n} \rightarrow 0$ in $L^{2}(\mathbb R^{n})$ .  What I am thinking is: since {$u_{n}$} is weakly convergent so it is bounded.  Since: $A$ is compact, & {$u_{n}$} is bounded $\implies$ the sequence {$Au_{n}$} has a convergent subsequence; say: {$Au_{n_{k}}$} . Now, does that help in someway??? Please help me to solve the problem.

I have a question. If $X$ and $Y$ are Banach spaces, we have to prove that a compact linear operator is completely continuous.  A mapping $T \colon X \to Y$ is called completely continuous, if it maps a weakly convergent sequence in $X$ to a strongly convergent sequence in $Y$ , i.e., $x_n\underset{n\to +\infty}\rightharpoonup x$  implies $\lVert Tx_n-  Tx\rVert_Y\to 0$.


In special relativity it is said that " Time and space cannot be defined separately from one another. Rather space and time are interwoven into a single continuum known as spacetime. " What is the exact meaning of this statement ? In SR, even though time is relative too but still in classical physics, we still needed time to define an event and what is the meaning of the term continuum ?

I'm having a hard time understanding how changing space means changing time. In books I've read people are saying "space and time" or "" but never explain what the difference is between the two concepts or how they are related.  How are the concepts of space, time, and space-time related?


Let $\gamma$ be a closed and continuously differentiable path in the upper half plane   $\{z\in C: z= x+iy, x\in R, y\in R, y\gt 0 \}$  not passing through the point $i$. Describe the set of all possible values of the integral $$\frac{1}{2\pi i}\int_{\gamma} \frac{2i}{z^2+1} dz$$  If $f$ doesn't contain $i$ then the value would be zero. If $f$ contains $i$ then it would be $1$.   But is this all??

let $\gamma$ be a closed continuosly differentiable path in the upper half plane  not passing through $i$. What are the possible values of the integral $$\frac{1}{2\pi i}\int_{\gamma}\frac{2i}{z^2+1}dz$$ well the integral can be broken like  $$\frac{1}{2\pi i}\int_{\gamma}\frac{2i}{(z+i)(z-i)}dz=$$  $$\frac{1}{2\pi i}\int_{\gamma}\frac{dz}{z-i}dz-\frac{1}{2\pi i}\int_{\gamma}\frac{dz}{z+i}dz=$$ by Cauchy Integral Formuale $$f(i)-f(-i)$$,so the second integral is $0$ as it is analytic in the upper half plane, but the first integral iss just $n(\gamma,i)$, which iss the windding number of $\gamma$ around $i$ what more I can say? Thank you.


Simple sql code gives strange result:  select '0.29'*100;   Result: 28.999999999999996  Another one:  select '0.28'*100;   Result: 28.000000000000004  What's going on? Is it a bug?  I couldn't find any other number that behaves like that.

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


I am on the move a lot and access StackExchange from my mobile device quite frequently. I appreciate the mobile version of the site, but I can't answer any question when it prompts me for a CAPTCHA, because my device is overwhelmed by the amount of content on the page and reboots. Could you please consider making the CAPTCHAs more mobile friendly?

When working with the mobile version of one of the mobile sites, my connection got really slow, and (I think this is what) caused Apple.SE to show me a captcha. I'm okay with that, but  I'd like to point out that the mobile site should have a mobile optimized captcha.  With slow internet connections in mind, I suggest to implement a mobile-optimized captcha page.


I am using Ubuntu 16.04 on AWS EC2 instance which has been working fine until this problem.  My problem is that I've used 100% of available inodes, as I discovered with this command:  $ df -i Filesystem     Inodes  IUsed  IFree IUse% Mounted on udev           124464    360 124104    1% /dev tmpfs          126787    449 126338    1% /run /dev/xvda1     524288 522638   1650  100% / tmpfs          126787      1 126786    1% /dev/shm tmpfs          126787      5 126782    1% /run/lock tmpfs          126787     16 126771    1% /sys/fs/cgroup tmpfs          126793      4 126789    1% /run/user/1000   The main culprits I discovered:  $ find / -xdev -printf '%h\n' | sort | uniq -c | sort -k 1 -n    1155 /usr/src/linux-headers-4.4.0-62/include/linux    1155 /usr/src/linux-headers-4.4.0-65/include/linux    1155 /usr/src/linux-headers-4.4.0-66/include/linux    1155 /usr/src/linux-headers-4.4.0-70/include/linux    1155 /usr/src/linux-headers-4.4.0-71/include/linux    1155 /usr/src/linux-headers-4.4.0-72/include/linux    1155 /usr/src/linux-headers-4.4.0-75/include/linux    1155 /usr/src/linux-headers-4.4.0-78/include/linux    1155 /usr/src/linux-headers-4.4.0-79/include/linux    1155 /usr/src/linux-headers-4.4.0-81/include/linux    1155 /usr/src/linux-headers-4.4.0-83/include/linux    1155 /usr/src/linux-headers-4.4.0-87/include/linux    1155 /usr/src/linux-headers-4.4.0-89/include/linux    1155 /usr/src/linux-headers-4.4.0-91/include/linux    1155 /usr/src/linux-headers-4.4.0-92/include/linux    1514 /usr/src/linux-headers-4.4.0-62-generic/include/config    1516 /usr/src/linux-headers-4.4.0-65-generic/include/config    1516 /usr/src/linux-headers-4.4.0-66-generic/include/config    1516 /usr/src/linux-headers-4.4.0-70-generic/include/config    1516 /usr/src/linux-headers-4.4.0-71-generic/include/config    1516 /usr/src/linux-headers-4.4.0-72-generic/include/config    1516 /usr/src/linux-headers-4.4.0-75-generic/include/config    1517 /usr/src/linux-headers-4.4.0-78-generic/include/config    1517 /usr/src/linux-headers-4.4.0-79-generic/include/config    1517 /usr/src/linux-headers-4.4.0-81-generic/include/config    1517 /usr/src/linux-headers-4.4.0-83-generic/include/config    1517 /usr/src/linux-headers-4.4.0-87-generic/include/config    1517 /usr/src/linux-headers-4.4.0-89-generic/include/config    1517 /usr/src/linux-headers-4.4.0-91-generic/include/config    1517 /usr/src/linux-headers-4.4.0-92-generic/include/config    1517 /usr/src/linux-headers-4.4.0-93-generic/include/config   Is it safe to delete these files, and if yes could you please tell me the exact command or commands to use on my PuTTY client?

I was trying to update my packages today:  $ sudo apt-get upgrade 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-headers-3.16.0-44-generic : Depends: linux-headers-3.16.0-44 but it is not installed E: Unmet dependencies. Try using -f.   So, I went ahead and tried apt-get -f install:  $ 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:   linux-headers-3.16.0-44 The following NEW packages will be installed:   linux-headers-3.16.0-44 0 upgraded, 1 newly installed, 0 to remove and 3 not upgraded. 3 not fully installed or removed. Need to get 0 B/9,101 kB of archives. After this operation, 64.5 MB of additional disk space will be used. Do you want to continue? [Y/n] y (Reading database ... 688666 files and directories currently installed.) Preparing to unpack .../linux-headers-3.16.0-44_3.16.0-44.59_all.deb ... Unpacking linux-headers-3.16.0-44 (3.16.0-44.59) ... dpkg: error processing archive /var/cache/apt/archives/linux-headers-3.16.0-44_3.16.0-44.59_all.deb (--unpack):  unable to create `/usr/src/linux-headers-3.16.0-44/scripts/genksyms/Makefile.dpkg-new' (while processing `./usr/src/linux-headers-3.16.0-44/scripts/genksyms/Makefile'): No space left on device dpkg-deb: error: subprocess paste was killed by signal (Broken pipe) Errors were encountered while processing:  /var/cache/apt/archives/linux-headers-3.16.0-44_3.16.0-44.59_all.deb E: Sub-process /usr/bin/dpkg returned an error code (1)   It's complaining saying No space left on device. df -Th tells me that there's sufficient space:  $ df -h Filesystem      Size  Used Avail Use% Mounted on /dev/sda6       3.3G  2.5G  571M  82% / udev            2.0G     0  2.0G   0% /dev tmpfs           395M   11M  384M   3% /run tmpfs           2.0G   28M  1.9G   2% /dev/shm tmpfs           2.0G     0  2.0G   0% /sys/fs/cgroup tmpfs           100M   72K  100M   1% /run/user tmpfs           5.0M  8.0K  5.0M   1% /run/lock /dev/sda7       9.3G  7.6G  1.3G  87% /usr /dev/sda8       188G  176G  3.0G  99% /home /dev/sda1       945M  394M  487M  45% /boot /dev/sda9       256G  9.6G  233G   4% /var   However, df -i tells me /usr has used up all the inodes.  These are the dirs and their inode usage:  /usr/bin = 2846 /usr/etc = 1 /usr/games = 8 /usr/include = 3204 /usr/lib = 42317 /usr/local = 105 /usr/lost+found = 1 /usr/sbin = 306 /usr/share = 228141 /usr/src = 348704   So, if I can clear out /usr/src (which contains the current and old kernels), I can probably resolve the issue. But, I keep running into the first error:  $ sudo apt-get purge linux-image-3.8.0-35-generic  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-headers-3.16.0-44-generic : Depends: linux-headers-3.16.0-44 but it is not going to be installed  linux-image-extra-3.8.0-35-generic : Depends: linux-image-3.8.0-35-generic but it is not going to be installed E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).   Any suggestions on how I can remove my old kernels? Thanks!


I used to have a program that did this quite well in OSX, but I haven't found any Windows alternative to joining multiple audio files into one larger audio file. The ones I've encountered so far are the type that you download and then don't really work until you pay a certain fee.  I'm working mostly with M4A files, but I can convert them to MP3's if necessary.  Thanks.

Motivation  I'm looking for a program that allows me to join a lot of mp3 files (an audio book) to a single large mp3 file. My mp3 player is able to remember the position inside a track, but it takes a while to reorganize the database if there are lots of files.  Already tried  I tried some programs (Wave Pad Sound Editor, Audacity), but with these it's all done inside a GUI with lot of manual action.  Question  Does anybody know a program that does this merge as a batch process, or at least without much interaction?  EDIT: I'm only looking for freeware.  EDIT: The software should run on Windows XP.


In my report, I am defining/describing some terms. What is a proper way to start and format a sentences like:     The term crawling denotes the practice of ...   Should I put the word/term crawling in quotes, bold, italic, or something else?  I think     The term "crawling" denotes the practice of ...   looks a bit ugly but is probably easier to read.  On Wikipedia, most terms seem to be formatted in bold font.

If I want to mention the word "furlong", for example, should I use furlong, "furlong", or 'furlong'? Also, am I correct in putting the punctuation outside the quotes?


I recently started getting the following error message when I tried to send an email from a group distribution list:      You can't send a message on behalf of this user unless you have permission to do so. Please make sure you're sending on behalf of the correct sender, or request the necessary permission. If the problem continues, please contact your helpdesk.   I have been able to use the group email in the From: section for over three months with no issues. As far as I am aware, no changes have been made to our profiles or accounts.   How can I fix this?

I get the following deliverable message when trying to send using another accounts email address:     You can't send a message on behalf of this user unless you have permission to do so. Please make sure you're sending on behalf of the correct sender, or request the necessary permission. If the problem continues, please contact your helpdesk.   The account has Full Access and Send As permissions in Exchange 2010. Deleting the address from the From: field (clicking the black cross), redownloading the GAL or deleting the C:\Users\username\AppData\Local\Microsoft\Outlook\Offline Address Books folder all fix the problem, but only for one email. After the first email is sent successfully I then continue to get the above message again.  Turning off Cached Exchange Mode also fixes the problem, but I want that on.  Is there another way to fix this?


I've installed Ubuntu 12.04 alongside with Windows 7. Everything is fine until i want to enter Ubuntu. When I start my pc, after normal boot, there is no Grub or OS Selection menu, and my system loads straight into Windows 7.   Any help would be very appreciated! Thanks!

I installed Windows 7, which ate Ubuntu's boot file. When starting up the computer, it now goes straight to Windows, without giving me the option of booting Ubuntu.   How can I get Ubuntu back?


I am using dynamic text and labeling this:  <dyn type="page" property="number"/>  but I only want it to label the first 50 characters and than if it has to shorten the name to than put et al. at the end.  Thoughts?

Is there a way to format the Name element generated as dynamic text from ?  This element serves as my title and it is too long and needs to be wrapped onto another line.


How to add new values to object in Javascript/Typescript? I have this JSON: {    "firstname":"chris",    "lastname":"bosh" }  and this one: {    "login":"c.bosh",    "email: "c.bosh@bosh.com" }  how to concat this two object into one, like this: {    "firstname":"chris",    "lastname":"bosh",    "login":"c.bosh",    "email: "c.bosh@bosh.com" }

I need to be able to merge two (very simple) JavaScript objects at runtime.  For example I'd like to:  var obj1 = { food: 'pizza', car: 'ford' } var obj2 = { animal: 'dog' }  obj1.merge(obj2);  //obj1 now has three properties: food, car, and animal   Does anyone have a script for this or know of a built in way to do this?  I do not need recursion, and I do not need to merge functions, just methods on flat objects.


I am trying to display a Powerpoint slide deck on an android tablet, but the slides contain fonts that don't exist in android.  Is there a way to install custom fonts on the tablet?  If so, how?

Does the Android operating system support installing new fonts?  I am that person who adores calligraphy and improving handwriting, and I am proud to say that my handwriting is now more beautiful than my teachers in almost every language I know! Anyway, can anyone answer that question (about Android fonts), because this will judge if I will buy a ruuning-Android tablet pc or not!


I would like to set a page that has a height of 6 meters. The following code fails.  \documentclass{article} \usepackage[paperheight=600cm]{geometry} \begin{document} \end{document}   The error message is:  /usr/local/texlive/2017/texmf-dist/tex/latex/geometry/geometry.sty:995: Dimensi on too large. <to be read again>                     \relax  l.995 \Gm@process   My code compiles fine with 500cm instead of 600cm. Therefore, what I am asking for should be possible. Is there a way to increase the limit or a better to achieve the goal?

Well, may be this is not really useful, but I've thought if it was possible to put all the document in one long page. I mean, if your document is going to be read in a computer, mix all the pages in a continuous page. If your document has 90 pages (A4), where each one is 21cm by 29.7cm the continuous document should be (more or less) one page which is 21cm by 90 · 29.7 = 2673cm. Is this possible? EDIT: Some things I would like to achieve:  The \newpage, \chapter{}, \part{}, etc. shouldn't go to a new page, they should only add more vertical space. The package pdfpages should add the pages continuously with almost no space between them. The titlepage, in this case, has a different color, so it could go alone in a basic A4 page (just to make things easier).  Question Is this possible?


This was meant to be a sub question in the comments of my last question but I think it is big enough to have its own post.  I know that electrons move because of the potential difference across the wire.  But do the electrons jump from the valence shell of 1 atom to the valence shell of another atom or do they flow in a swarm without interacting with any atoms? Here I am talking about electron flow in a metallic conductor.  And what about insulators? Let's say we have an insulator in the middle of a conducting circuit. How will the it prevent electrons from going through?

On a systems level, I understand that as electrons are pushed into a wire, there is a net field and a net electron velocity.  And I've read that the net electron drift is slow.  But electricity travels through the wire, essentially at c, and I want to understand that mechanism.  My apologies if my question is poorly stated, I know bare bones undergraduate quantum theory circa 1990s but it doesn't explain the motion of electricity in detail.  Here's my conception, I'm hoping someone will fill in the holes, ha ha.  An electron moves into the wire.  It's got a kinetic energy.  After travelling a short distance, it spontaneously emits a photon, which hits another electron in a valence shell.  That electron then presumably does the same.  If this conception is simply wrong, please enlighten me.  The questions that arise:   Presumably at this level, electrons are acting more like waves and less like particles, but is there any classical component in the picture, ie are electrons coming in imparting other electrons with kinetic energy through repulsion, or does it not work that way? If electrons momentarily have energy, then pass it on by a photon, what determines when that photon is emitted, and what frequency it will be?  I assume that electrons in this cloud are not limited by any kind of exclusion principal, and that any frequencies are possible? Why should a photon emitted by an electron be in the direction of travel?  Conservation of momentum tells me that if an electron is moving, the photon should be emitted in that direction, slowing the electron, but could an electron emit a photon in the opposite direction?  If it did, I assume it would somehow have had to absorb energy from elsewhere? That sounds possible by analogy with quantum tunneling. What is the mechanism by which electrons propagating increase the temperature of the material?  Are they transmitting energy to the electrons in the valence shell, which tug at the nucleus, do some photons hit the nuclei directly, or is there some other way?  Presumably, electricity travels slower than light, because there is some time in each exchange, and some time when electrons are moving at sublight speeds before emitting a photon.  By how much is this slower than light, and what is the speed of each interaction?


When I am using Chrome, after some time the system freezes. I don't know why it's happening with Ubuntu 18.04 LTS. I keep updating my system.

I am using chrome Version 50.0.2661.94 (64-bit) and ubuntu 16.04. Most of the time chrome get stuck and hangs whole system.  Does anyone face the same issue?


Quarks are bound by gluons. Gluons have a mass of 0, while mass of quarks is only 5%. Where is the missing 95%?

We know that the sum of the masses of the quarks in a proton is approximately $9.4^{+1.9}_{-1.3}~\text{MeV}/c^2$, whereas the mass of a proton is $\approx931~\text{MeV}/c^2$. This extra mass is attributed to the kinetic energy of the confined quarks and the confining field of the strong force. Now, when we talk about energetically favourably bound systems, they have a total mass-energy less than the sum of the mass-energies of the constituent entities. How does a proton, a bound system of quarks with its mass-energy so much more than its constituent entities, remain stable? The strong force and other energetic interactions supposedly contribute this mass-energy by the mass-energy equivalence principle, but how exactly does this occur?


Steps to reproduce  Have an image of size at least x on your computer, where x is somewhere between 4088 KB and 4277 KB. (I haven't gone to the trouble of finding the smallest filesize x that triggers this behavior, but I'd imagine it's 4096 or 4097 KB.) Click on the "Image  Ctrl+G" button in the Markdown editor. Select the "From my computer" radio button. Click on "Choose File" and select the image mentioned in step 1. Click on "Add Picture".  What happens  A dialog box pops up that reads "For security reasons, framing is not allowed; click OK to remove the frames."  If you click "OK", and your post contains unsaved work, a "Confirm Navigation" box pops up that reads "You have started writing or editing a post. Are you sure you want to leave this page?", with options "Leave this Page" and "Stay on this Page".  If you click "Leave this Page", you are taken to a very undescriptive error page at . If you click "Stay on this Page", the "Uploading" animation on the "Add Image" box runs forever and does nothing.   If you click "OK", and your post does not contain unsaved work, you are taken to a very undescriptive error page at at . If you cancel out of the dialog box, the "Uploading" animation on the "Add Image" box runs forever and does nothing.    What should happen The user should be shown some sort of useful error message like "You cannot upload images larger than x kilobytes in size", and the "Uploading" animation shouldn't spin forever. (Also, the warning about frames and security looks bizarre if you don't know what's going on.) Sites tested  MSO SO Anime.SE

Ok first, there's that lugubrious use of the semicolon; not necessary.  Second, I didn't open a frame!  You did!  Alls I tried to do is upload a 5MB animated .gif file via Imgur.    Looking further into this, Imgur actually posts an error when you upload an animated .gif larger than 2MB.    Go figure!


I'm trying to implement simple case (basically find text between two tags whatever they are). I want to get lines   /* my comment 1 */  /* my comment 2 */  /* my comment 3 */  as an output. It seems I need to limit capture group to 1? Because on string Hello /* my comment 1 */ world I get what I want - res[0] contains /* my comment 1 */  #include <iostream> #include <string> #include <regex>  int main(int argc, const char * argv[]) {     std::string str = "Hello /* my comment 1 */ world /* my comment 2 */ of /* my comment 3 */ cpp";      std::cmatch res;     std::regex rx("/\\*(.*)\\*/");      std::regex_search(str.c_str(), res, rx);      for (int i = 0; i < sizeof(res) / sizeof(res[0]); i++) {         std::cout << res[i] << std::endl;     }      return 0; }

I have this gigantic ugly string: J0000000: Transaction A0001401 started on 8/22/2008 9:49:29 AM J0000010: Project name: E:\foo.pf J0000011: Job name: MBiek Direct Mail Test J0000020: Document 1 - Completed successfully  I'm trying to extract pieces from it using regex. In this case, I want to grab everything after Project Name up to the part where it says J0000011: (the 11 is going to be a different number every time). Here's the regex I've been playing with: Project name:\s+(.*)\s+J[0-9]{7}:  The problem is that it doesn't stop until it hits the J0000020: at the end. How do I make the regex stop at the first occurrence of J[0-9]{7}?


I'm really new to blender and I'm trying to add thickness to a fairly complex polygonal chain. I've seen a lot on how to do it with Bezier curves but nothing on how to do it with polygonal chains. Does anybody know how to?  That orange dot in the middle is what I'm talking about the big mess on the left is my polygonal chain getting sucked towards it:    UPDATE: My problem was fixed thanks to this question and answer -

I want to give these line segments a continuous cylinder shape, like a Spaghetti noodle. My aim is to make this path visible in render mode. At the moment you are not able to see it in render mode because it has zero thickness.  I already converted them into a Bezier curve and played around with the Bezier Circle. The result were a lot of cylinders behind each other with a lot of gaps between them because the whole line has edges as you can see on the picture.  I also tried to solve the problem with a Skin-Modifier, but this didn't give me a good solution either. Maybe I should combine it with another Modifier.  So I was wondering if it's even possible to convert an 3D edged path into a curve path with a cylinder shape.  I would be very glad if someone could tell me how I get a good solution.  Thank you very much!


I have these NgSpice rawfiles that are generated in ASCII format instead of binary format. I would like to know please what command to use to force their generation in binary instead or ASCII format when running the NgSpice simulation in batch mode? If no such thing exists it there a command that converts ASCII files to binary ones? Thanks in advance

This has taken me a couple of days to solve. I have a set of NgSpice raw files that I would like to exploit so as to visualize the voltage distributions in different circuits. What is the python command to use or python package to import in order for me to achieve this. Note: I am a bit familiar with the PySpice python package, but from what I have read and understood it works when you use it to create your netlist and run it, by using the already stored variables in its memory. In my case however, raw files are already generated... Hope I was clear enough.


So. There are spinning black holes. Could there be a not spinning black hole?   Or even if it would exist, it would start spinning because of stuff?

Can we assume that most (if not all)  black holes are rotating, due to conservation of momentum?  I am excluding the micro world from this question, just thinking of the range of stars on the main sequence of the H-R diagram as they shrink over time.    Can anyone give me an example of non-rotating macro sized B.H., e.g a binary system where each star counter-rotates relative to the other and explain how they may, (if they can)  at least slow down each others's rotational velocity?


App version: 1.0.21  Device: Huawei Ascend G510 (running Android 4.1.1)  Problem: When viewing a question, if there are comments the link to click to view more comments is being overlapped by the Add comment button (picture below).  This was reported on  question and was resolved, but it is happening again.

In the Android app, the "x more comments" phrase is cut off by the button next to it, "Add a comment":    It looks like the rest of the phrase is underneath the button and there is some space to the left of the phrase. Can we shift the "x more comments" phrase more to the left so it doesn't get cut off by the "Add a comment" button? At the very least, please allow the phrase to not be cut off by the "Add a comment" button somehow.


I can't see the Web page displaying properly. I have been trying to access it since morning but unable to do so because it's not displaying the web page properly. Yes, Meta Stackoverflow is working fine. I'm not even able to login into Stackoverflow.  Browser I'm using: Firefox Latest version on Windows 7 Professional  Attaching the Image of stackoverflow :

I originally thought this was a mobile-theme related issue, but it is not. The css of the page does not load.  I guess I could clear my browser's cache. Is there any other option?      Edit: I do not have the "full site" option at the very bottom :(      Edit2: this is not an issue with the mobile theme. Here's my data according to the requests from      Samble CDN file:    My IP: 186.48.230.46   Tracing route to sstatic.stackexchange.netdna-cdn.com [69.174.57.102]   over a maximum of 30 hops:      1    21 ms    15 ms    25 ms  pucor1bras1.antel.net.uy [200.40.21.7]    2    16 ms    16 ms    18 ms  ibb2cor1-7-2-93.antel.net.uy [200.40.21.81]    3    20 ms    16 ms    16 ms  ibb2agu1-1-3.antel.net.uy [200.40.16.73]    4    29 ms    56 ms    21 ms  ibr3agu1-p1.antel.net.uy [200.40.18.38]    5   167 ms   159 ms   159 ms  So5-2-0-0-grtbueba2.red.telefonica-wholesale.net.7.16.84.in-addr.arpa [84.16.7.57]    6   156 ms   159 ms   163 ms  Xe5-1-3-0-grtmiabr7.red.telefonica-wholesale.net.125.142.94.in-addr.arpa [94.142.125.122]    7   200 ms   209 ms   186 ms  Xe-0-0-2-0-grtwaseq3.red.telefonica-wholesale.net [94.142.124.109]    8   198 ms     *      196 ms  213.140.55.90    9   199 ms   197 ms   204 ms  po2-20G.ar4.DCA3.gblx.net [67.16.133.82]   10   222 ms   195 ms   194 ms  PACKETEXCHANGE-LTD.TenGigabitEthernet2-4.ar4.DCA3.gblx.net    [64.211.83.106]   11   205 ms   197 ms   197 ms  te4-7.cr1.was2.us.packetexchange.net [69.174.120.125]   12   180 ms   206 ms   188 ms  69.174.31.2   13   194 ms   192 ms   221 ms  69.174.57.102        Trace complete.      Tracert to the origin:   Tracing route to sstatic.net [64.34.119.12]   over a maximum of 30 hops:      1    29 ms    33 ms    38 ms  pucor1bras1.antel.net.uy [200.40.21.7]    2    38 ms    19 ms    16 ms  ibb2cor2-7-2-93.antel.net.uy [200.40.21.209]    3    66 ms    93 ms    73 ms  ibb2uni2-1-3.antel.net.uy [200.40.16.98]    4    46 ms    24 ms    20 ms  ibr3uni1-p2.antel.net.uy [200.40.22.166]    5   214 ms   224 ms   198 ms  so-3-1-0.mia11.ip4.tinet.net [77.67.78.189]    6   221 ms   253 ms   224 ms  xe-0-2-0.nyc20.ip4.tinet.net [89.149.183.2]    7   301 ms   291 ms   304 ms  peer1-gw.ip4.tinet.net [77.67.70.194]    8   230 ms   225 ms   223 ms  10ge.xe-0-0-0.nyc-telx-dis-2.peer1.net [216.187.115.182]    9   263 ms   204 ms   199 ms  oc48-po3-0.nyc-75bre-dis-1.peer1.net [216.187.115.134]   10   209 ms   208 ms   207 ms  gwny01.stackoverflow.com [64.34.41.58]   11   202 ms   217 ms   221 ms  stackoverflow.com [64.34.119.12]        Trace complete.   Datacenter: Miami


The original prompt was: Write a function called lastLetter that takes a string and returns the very last letter of that string: lastLetter("abcd") should return "d" I was able to write it so that I could define lastLetter as a variable in the console log to produce "d" as requested; I'm just curious if someone can help me understand how I would edit this to create a function and produce the same result? Or does it matter if it's a variable or function, like is one more useful than the other? Working code let alpha = "abcd"; let lastLetter = alpha[alpha.length - 1] console.log(lastLetter) // "d";  Function returns "undefined" function lastLetter() { let alpha = "abcd"; let lastLetter = alpha[alpha.length - 1]  } console.log(lastLetter) // "undefined";

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?


I have a dual boot with windows 8 and ubuntu 16 on my laptop. I have 20gb for my ubuntu which I want to expand. I just unallocated 200gb of my windows partition via windows disk management. I booted again ubuntu with my usb drive without installing and tried Gparted to resize/move my ubuntu partition. But I can't expand ubuntu partition at all. This is what I get in Gparted:

Here I want to merge unallocated space to ext4 partition. But during running in Ubuntu it is not allowed. Am I right? It has key picture. I must do that Ubuntu DVD booting from it and selecting try Ubuntu there with GParted, I must merge this unallocated part by right clicking on ext4 partition and then selecting shrink. Am I right?   Then for swap area I want to take 5GB from extended partition (which is now called D on Windows). Can I format this partition in Windows or should I use GParted? But in GParted it has key picture. Or in the same way should I do this during trying Ubuntu to merge unallocated space to ext4? Thank you for your answers.


I have a program that is designed for a 64-bit OS, but I only have a 32-bit OS at the moment. Is there any way to convert the program to 32-bit or install the 64-bit program on a 32-bit OS?

I have a 64-bit machine that has Windows 7 32-bit and Ubuntu 32-bit installed as a dual boot setup. Can I run 64-bit software on top of these 32-bit OSes, or are they a "bottleneck" limiting the true capability of the underlying hardware?


Thanos’ whole aim was to get the Infinity Stones in order to remove half the living beings in the universe at the snap of a finger, but, is this all the Gauntlet and Stones are able to do. For instance, if someone got the Stones could they give themselves instant wealth, make grass turn red, make someone love them?   For that matter could Iron Man instead of disappearing Thanos, make his army hate him and refuse to follow him, or could he have made Thanos lose his will to rebuild the universe.   Are the Stones basically a wishing machine or are they limited in what they can achieve?    To confirm I am looking for examples or answers from any canon source, both MCU and in the comics.

I am wondering if there is anything in Marvel comic book canon or in the MCU that says that the Infinity Gauntlet has the power to make someone fall in love with the person wearing the Infinity Gauntlet, or that the wearer of the Infinity Gauntlet can use the Infinity Gauntlet to make two strangers fall in love with each other? Perhaps the combined power of the Mind Stone and the Soul Stone would make two people fall in love.


I just accidentally quick formatted a micro SD card, with about 8 GB of pictures on it. I didn't know it was plugged in, and I meant to format something else.  Worse, I copied 4 files onto it, totaling about 500MB - permanently destroying what was there. It was FAT32, and was formatted to that. How do I go about recovering whatever I can?

I have a dell laptop that recently "died" (It would get the blue screen of death upon starting) and the hard drive would make a weird cyclic clicking noises.  I wanted to see if I could use some tools on my linux machine to recover the data, so I plugged it into there.  If I run "fdisk" I get:  Disk /dev/sdb: 20.0 GB, 20003880960 bytes 64 heads, 32 sectors/track, 19077 cylinders Units = cylinders of 2048 * 512 = 1048576 bytes Disk identifier: 0x64651a0a  Disk /dev/sdb doesn't contain a valid partition table   Fine, the partition table is messed up.  However if I run "testdisk" in attempt to fix the table, it freezes at this point, making the same cyclical clicking noises:  Disk /dev/sdb - 20 GB / 18 GiB - CHS 19078 64 32 Analyse cylinder   158/19077: 00%   I don't really care about the hard drive working again, and just the data, so I ran "gpart" to figure out where the partitions used to be.  I got this:  dev(/dev/sdb) mss(512) chs(19077/64/32)(LBA) #s(39069696) size(19077mb)  * Warning: strange partition table magic 0x2A55. Primary partition(1)    type: 222(0xDE)(UNKNOWN)    size: 15mb #s(31429) s(63-31491)    chs:  (0/1/1)-(3/126/63)d (0/1/32)-(15/24/4)r    hex:  00 01 01 00 DE 7E 3F 03 3F 00 00 00 C5 7A 00 00  Primary partition(2)    type: 007(0x07)(OS/2 HPFS, NTFS, QNX or Advanced UNIX) (BOOT)    size: 19021mb #s(38956987) s(31492-38988478)    chs:  (4/0/1)-(895/126/63)d (15/24/5)-(19037/21/31)r    hex:  80 00 01 04 07 7E FF 7F 04 7B 00 00 BB 6F 52 02   So I tried to mount just to the old NTFS partition, but got an error:  sudo mount -o loop,ro,offset=16123904 -t ntfs /dev/sdb /mnt/usb NTFS signature is missing.   Ugh.  Okay.  But then I tried to get a raw data dump by running  dd if=/dev/sdb of=/home/erik/brokenhd skip=31492 count=38956987    But the file got up to 59885568 bytes, and made the same cyclical clicking noises.  Obviously there is a bad sector, but I don't know what to do about it!  The data is still there... if I view that 57MB file in textpad... I can see raw data from files.  How can I get my data back?  Thanks for any suggestions,  Solution:  I was able to recover about 90% of my data:   Froze harddrive in freezer Used Ddrescue to make a copy of the drive Since Ddrescue wasn't able to get enough of my drive to use testdisk to recover my partitions/file system, I ended up using photorec to recover most of my files


I'm an architecture student. I draw, design and render with Copic markers and I also have a part time job designing logos and catalogs. I use a 24 inch monitor.  Now I want to buy a Wacom Intuos Pro, and I can't choose between medium and large. Initially I wanted to buy the large one, but I've heard it's way too big. Personally, I think the active area on the medium one is not enough. I really dont know what to do – please help.

I am a high school student with an interest for drawing tablets for some hobby. I went to check on a store that sell Intuos, a sales representative (or something) of Wacom told me that most students buy the medium sized tablets. Even the staff said that since it is always bought the supplies of the medium size are a lot more than the small size.  I am on a tight budget (which is why I am buying the Intuos), and the small size seems small to me (when my hands are open, my thumb and my pinky would reach the sides). But then, why would Wacom sell the Manga variant in small? Is the staff just saying that so I would buy the more expensive one?  I have enough savings from my small allowance to buy the small size right now, should I wait for another month so that I can buy the medium size?


I have two simple classes, Card and CardTester. One of the methods in Card checks to see if two cards are equal to one another.   However, when using calling the method matches() in CardTester, it returns false, when it should return true.  public class Card {   private String rank;   private String suit;   private int val;    public Card(String cardrank, String cardsuit, int cardval) {     rank = cardrank;     suit = cardsuit;     val = cardval   }    public boolean matches(Card a) {     if (this.val == a.val && this.suit == a.suit && this.val == a.val)    {       return true;     }      else {       return false;     }   }    Calling the method in another class:  public static void main(String[] args){   Card c2 = new Card("king", "clubs", 10);   Card c3 = new Card("king", "clubs", 10);    if (c2.equals(c3)) {     System.out.println("Cards are equal");   }    else {     System.out.println("Cards aren't equal");   }   The output ends up being "Cards aren't equal" when it should be "Cards are equal".

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


The volume bar is stuck in lower left screen. I cannot use it or get rid of it. I cannot reach the task bar volume icon because it is covered by the stuck volume bar. What other steps can I take?

Occasionally, I get part of an application lingering behind on my desktop:    This is part of a context menu for an application. It is always top-most, meaning that it is always on the screen, and I cannot click on it (it just clicks through it). It has happened before, sometimes with whole windows. It remains on screen even if the application it originated from is no longer running.  How do I get rid of it without rebooting?


As all we know, this command is very danger, i have an idea as following, but i don't know how to accomplish. If you have best solution for it, welcome to write down.  I think we can create a directory to simulate trash, every time we delete something, those files/directories be moved to the trash, and there is a regular script, remind us of emptying trash.

I would like to know if there is a command I can issue in a terminal so I do not classically remove (rm) the file, but instead move it to trash (i.e. Nautilus Move to Trash behavior).  In case there is such a command, I would also be interested in knowing what it is.


I have an alias to a ffmpeg command to start recording a session like this:  alias sreq='ffmpeg -f x11grab -r 24 -s 1024x768 -i :0.0 -qp 0 -c:v libx264 -preset veryslow'   I can just type sreq filename.mkv to start recording. This is pretty good but I'd like to fix this up a bit.  since I always record in .mkv format, how can I have it so that i can avoid having to type .mkv   how could I rework this alias command or something so that I can just type sreq filename or sreq /path/to/filename  and have it work as expected?

For bash script, I can use "$@" to access arguments. What's the equivalent when I use an alias?


Can a cyclic group have more than two generators?  for example the group $\mathrm{Z}$ has two generators $-1$ and $1$, but can a group have more than two generators?

My question is: Can you find a cyclic group with n generators?  I know that zero (or any other identity element for that matter) is included, so there would be for $Z_n$ at most n-1 generators. However, is it possible to say that $Z_{n+1}$ could provide n generators?  Any help would be much appreciated! If you wouldn't mind, I would appreciate it if you provide enough detail to really help me understand so I can learn. Thanks in advance!


mFirebaseInstance.getReference("app_title").addValueEventListener(new ValueEventListener() {     @Override     public void onDataChange(DataSnapshot dataSnapshot) {         Log.e(TAG, "App title updated");          String appTitle = dataSnapshot.getValue(String.class);         long s = dataSnapshot.child("daysOnWhichPresent").getValue(Long.class);          // update toolbar title          textGrid.setText(appTitle);     }      @Override     public void onCancelled(DatabaseError error) {         // Failed to read value         Log.e(TAG, "Failed to read app title value.", error.toException());     } });   java.lang.NullPointerException: Attempt to invoke virtual method 'long java.lang.Long.longValue()' on a null object reference at omari.hamza.storyviewdemo.MainActivity$15.onDataChange(MainActivity.java:673) at com.google.firebase.database.core.ValueEventRegistration.fireEvent(ValueEventRegistration.java:75) at com.google.firebase.database.core.view.DataEvent.fire(DataEvent.java:63) at com.google.firebase.database.core.view.EventRaiser$1.run(EventRaiser.java:55)

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


I'm looking for a way to replace \DeclareMathOperator{\Operator}{Operator} by something which would resemble \MathOperator{Operator}. I tried to define a new command \newcommand\MathOperator[1]{\DeclareMathOperator{\#1}{#1}} and then call it \MathOperator{MyOperator} but this doesn't seem to work, I got the following error: "Undefined control sequence." when calling $\MyOperator$. Any idea what I should do?  Thanks a lot.

The preambles of my LaTeX documents often include many many lines of \DeclareMathOperator instructions, e.g.  \DeclareMathOperator{\Rep}{Rep} \DeclareMathOperator{\Tet}{Tet} \DeclareMathOperator{\Maps}{Maps} \DeclareMathOperator{\Diff}{Diff}   Is there a nice way to map some macro over a list, so I could do this more concisely, and with less copying and pasting when I add a new math operator?


This image that i'm working on in cycles render is almost done but I stuck at the part of the block behind the cubes. It has a shadow on the white plane. The only thing that's wrong is that I don't want the plane to show up. Only the shadow. In "film" I already set the Transparent to "true" and in the compositing I did the thing with using only that layer and than substract and invert and all of that. But I can't seem to find any solutions. It's a movie clip so the compositing is more than just that.

I am superimposing CGI over video footage, and have run into a problem in making materials for objects that act as 'shadow catchers'.  Essentially I want a shader that is shadeless—like an emitter—but catches shadows and light from other objects. This is so I can reconstruct objects in footage so other objects in the scene interact convincingly with them.  Here's an overcomplicated diagram to illustrate my point:   (In this particular scenario, the problem could be glossed over by using RGB curves, but that is definitely not the case with more complicated scenes)  Isn't this a common situation? How to the real guys do it? Thank you.  (I am welcome suggestions of other ways of doing this.)


In C++, it is advisable to declare global variables inside the main program, or outside it, before everything else? I mean, what is the difference between  #include <iostream>  int variable;  int main() {    //my program      return 0; }   and  #include <iostream>  int main() {      int variable;      //my program      return 0; }   In which case should I use which one?

In C/C++, are global variables as bad as my professor thinks they are?


I am asked to prove the following question regarding convergence of $k^\text{th}$ moment of a random variable:  $E(|X|^k) < \infty$ if and only if $\sum_{i=1}^{\infty}i^{k-1}P(|X| \geq i) < \infty$ for any integer $k > 1$. I have managed to prove the direction that given $\sum_{i=1}^{\infty}i^{k-1}P(|X| \geq i) < \infty$, we have $E(|X|^k) < \infty$. But I am stuck at the other direction.   The proof I have come up with now is as follow:  Construct $X_i^k(\omega) = (i-1)^kI_{A_i}$ where $A_i = \{i-1 \leq |X| < i\}$. Then $|X|^k \geq \sum_{i=1}^{\infty}X_i^k$, and we have $E(|X|^k) \geq E(\sum_{i=1}^{\infty}X_i^k)$. Since $\sum_{i=1}^{\infty}X_i^k$ is a discrete random varaible taking value $(i-1)^k$ with probability $P(i-1 \leq |X| < i)$. We have $$ E(|X|^k) \geq \sum_{i=1}^{\infty}(i-1)^kP(i-1 \leq |X| < i). $$ I know the next step is to somehow show that the RHS is greater than $\sum_{i=1}^{\infty}i^{k-1}P(|X| \geq i)$, but I am stuck at this point and I don't know how to proceed. Can anyone give some hints? Thanks very much!

Consider a non-neg r.v $X$ and fix a positive integer $n$, I am trying to show that a necessary and sufficient condition for the $n$th order expectation to exist is that $\sum_{i\in\mathbb{N}}i^{n-1}P(X\ge i)$ converges.   Attempt: We have a well established relation,  $\sum_i P(X\ge i)\le EX < 1+\sum_iP(X \ge i)$, I am convinced this is used but i am unsure how to to incorporate $i^{n-1}$ . If we consider a partition of the real line given by $A_i=\{i-1\le X < i\}$ and then let choose $X_i=(i-1)I_{A_i}$ then the series is a discrete r.v. with $E(\sum_i X_i)=\sum iP(X\ge i)$ which is similar to the form we need it in. But im unsure where to go from here.


I know that I can't just take someone's photo from google images and use it on my site without looking into the licensing, but could I take a photo of let's say a generic wood desk or pen and trace it for use in my illustration without worrying about getting sued?  Is it unethical or bad practice to do so?

This is a legal question and I want to know if I can continue the way I work in a commercial environment. This is not about if I can blatantly take images from the web and use them as they are.  What I do is mostly icons and iconographic imagery where in the end no one can tell if I used an image that doesn't belong to me as a starting point.  Here is an example.    See, technically I stole.  I'd like to know if this is perfectly okay and counts as a new work or if it's sort-of okay because I might not get into legal trouble. Or maybe I should be really careful.  I actually don't know.


The  mention commands such as \@author and \@director, and latex.ltx is full of them. However, when I use \@author in my document, it just outputs the word "author". What does the @ in command names mean?

Many LaTeX “hacks” begin with \makeatletter and end with \makeatother. What do these commands do?


I have an abstract algebra proof I can not complete. The proposition goes as follows: Consider a group $G$ of order $m$. If $n$ divides $m$, prove that $G$ has a subgroup of order $n$. This question is based off the fundamental theorem of finitely generated abelian groups.   Proof: My idea was to let $m = P_{1}^{\alpha_{1}}...P_{k}^{\alpha_{k}}$ and $n = P_{1}^{\beta_{1}}...P_{l}^{\beta_{l}}$ where $\beta_{i} \leq \alpha_{i}$. Now after this, I am a little unsure what to do. Applying the theorem can let me write this as a direct product, but I am not sure how that leads to show $G$ has a subgroup of order $n$.   I am open to answers since this is something I am independently studying in my spare time.  Thanks!  NOTE: I am not looking to prove this by induction. I want to use the fundamental theorem of finitely generated abelian groups.

I'm trying to prove that the converse of Lagrange's theorem is true for finite abelian groups (i.e. "given an abelian group $G$ of order $m$, for all positive divisors $n$ of $m$, $G$ has a subgroup of order $n$"). This is an exercise from a book, and it is in the section on finite abelian groups, so I know I have to use the fundamental theorem of finite abelian groups. I have come up with a proof, but it seems a bit messy, and I'm not entirely sure if it's correct. It is given below.     Let the order of $G$ be $m$ = $p_1^{\alpha_1} \ldots p_k^{\alpha_k}$. It is known that $G$ is a direct product of $p$-groups, say:      $$G = G_1 \times \ldots \times G_k$$      where each $G_i$ is a $p_i$-group. By the fundamental theorem of finite abelian groups, each $G_i$ is isomorphic to a direct product of cyclic groups of the form      $$\mathbb{Z}_{{p_i}^{\beta_1}} \times \ldots \times \mathbb{Z}_{{p_i}^{\beta_l}},$$      where $\beta_1, \ldots, \beta_l$ are positive integers such that $\sum_{j=1}^l \beta_j = \alpha_i$. Now if $n$ divides $m$, then we must have      $$n = p_1^{\gamma_1} \ldots p_k^{\gamma_k}$$      for some $\gamma_1, \ldots, \gamma_k$ with $0 \leq \gamma_i \leq \alpha_i$.      Claim: Each $G_i$ has a subgroup of order $p_i^{\gamma_i}$      Proof: As above, we have that       $$ G_i \cong \mathbb{Z}_{{p_i}^{\beta_1}} \times \ldots \times \mathbb{Z}_{{p_i}^{\beta_l}} $$      where $\beta_1, \ldots, \beta_l$ are positive integers such that $\sum_{j=1}^l \beta_j = \alpha_i$.      Now since $0 \leq \gamma_i \leq \alpha_i$, we can find   $l$ numbers $\delta_1, \ldots , \delta_l$ such that $\gamma_i = \sum_{j=1}^l \delta_j$, and $0 \leq \delta_j \leq \beta_j$. (This choice of numbers is not necessarily unique).      Then $p_i^{\delta_j} | p_i^{\beta_j}$ for each $j = 1, \ldots , l$. Hence, for each factor $\mathbb{Z}_{{p_i}^{\beta_j}}$, there exists a subgroup of order $p_i^{\delta_j}$, namely $\mathbb{Z}_{{p_i}^{\delta_j}}$ (using the fact that the converse of Lagrange's theorem is true for finite cyclic groups). Taking the direct product of each of these subgroups, we get a new subgroup $G_i'$ of $G_i$:      $$G_i' \cong \mathbb{Z}_{{p_i}^{\delta_1}} \times \ldots \times \mathbb{Z}_{{p_i}^{\delta_l}}$$      The order of this subgroup is $p_i^{\delta_1} \times \ldots \times p_i^{\delta_l} = p_i^{\delta_1 + \ldots + \delta_l} = p_i^{\gamma_i} $. So we have found a subgroup of $G_i$ of order $p_i^{\gamma_i}$, as required.      So each factor $G_i$ in the product $G = G_1 \times \ldots \times G_k$ has a subgroup $G_i'$ of order $p_i^{\gamma_i}$.       Therefore, $G$ has a subgroup   $$G_1' \times G_2' \times \ldots \times G_k'$$       of order $p_1^{\gamma_i}...p_k^{\gamma_k} = n$, which completes the proof.   I have two questions about this: firstly, does this proof seem to work? Secondly, is there a way to make the proof more concise (e.g. a way to prove the statement without using all these indices)?


Im using a very simple and clean code to render a modal in my page:
I'm the Modal Window!
     .modal {     /* some styles to position the modal at the center of the page */     position: fixed;     top: 50%;     left: 50%;     width: 300px;     line-height: 200px;     height: 200px;     margin-left: -150px;     margin-top: -100px;     background-color: #f1c40f;     text-align: center;      /* needed styles for the overlay */     z-index: 10; /* keep on top of other elements on the page */     outline: 9999px solid rgba(0,0,0,0.5); }     Is there a clean and reliable way to detect when somebody clicks outside of the modal?

I have some HTML menus, which I show completely when a user clicks on the head of these menus. I would like to hide these elements when the user clicks outside the menus' area.  Is something like this possible with jQuery?  $("#menuscontainer").clickOutsideThisElement(function() {     // Hide the menus });


I’m running the LiveCD of Kubuntu (latest release). However, to login, it is asking for a password.  Where I can get this information for LiveCD credenials?

When I boot Ubuntu 10.04.3 from a live CD, it asks me to enter a username and password. I have not booted before, and I haven't created an account.


In my opinion, providing us with an active user page that shows the list of recent active users is useful as we can monitor the active users without visiting each user profile.  The list can be arranged in a grid of m rows by n columns and accompanied by labels representing the their reputations (and other info that you think they are important) and activities  such as "seen 2 minutes ago".  The following figure illustrates my idea. I am sorry. There is a typo in the following figure, Active must be changed to active to make it parallel to the other existing labels.     I think it is not too difficult to implement this. By adding a new action method and editing the view, done!  Of course it is not urgently requested feature. If it is useful, it can be put in the development to-do list so it can be implemented together with other useful requests at once.  Any responses are welcome! Regardless of how difficult it is, could you explain whether or not there are negative effects of this request? Down voting without informative comments looks barbaric. :-)  Edit:  If it is about user privacy, why is there a "seen 2 minutes ago" in the user profile page? I don't think there is a difference if we implement this feature.

Sometimes I need to view who is online, but clicking his/her profile one by one seems to be tedious/cumbersome task. It will be convenient if there is a new button "Last Activity" providing us with a rectangular list of users and the seen values (e.g., 20 seconds ago, just now, etc). Viewing 50 users in one page is also helpful, I believe.  Is it worth adding a new sorting button named "Last Activity" to the Users page?


I know this has been asked before. But I am trying to connect to my Windows network. I do not know Ubuntu very well but am learning. My laptop is running Ubuntu 18.04.05 and my Windows computers are all Windows 10. How do I connect to my Windows network? Dan

User story follows, just to illustrate better how this is an Ubuntu question ;-)  I, as an Ubuntu user (on 20.04.2), would like to connect to my Windows 10 machine via a LAN cable (preferably via the SMB protocol) so that I can copy/move over downloaded files and documents that I have authored there because at the end of the day I want my Ubuntu machine to be the canonical (ha!) home for my documents.  I know this is not a Windows Q/A site, so feel free to not go into details (if you don't want to) about the steps that I need to carry out on the Windows machine, but please, could you at least give a list of steps about the Samba setup as keywords that I can follow and google one by one? What I need: Unfortunately it seems I can't just pull over an entire directory and be done with it. Instead, I would like to use a graphical file manager (Nautilus) to "merge" the contents of some select remote directories into their corresponding local ones, and manually resolve any conflicts should they arise. What I have tried: I have tried to enable NFS on Windows (because I already have some NFS experience), but have found out that Windows 10 still has support for only NFS 3, and therefore transferable filenames are limited to only ASCII characters; so that's not good. That's why I'm aiming for Samba.


I'm looking for a way to update an attribute programmatically (especially when inside an update() function of an SQLAlchemy class)  def update(self, **kwargs):     for kwarg in kwargs:         setattribute(self, kwarg, kwargs[kwarg])   This does not seem to work, neither this:  def update(self, **kwargs):     for kwarg in kwargs:         self[kwarg] = kwargs[kwarg]

Suppose I have a python object x and a string s, how do I set the attribute s on x? So:  >>> x = SomeObject() >>> attr = 'myAttr' >>> # magic goes here >>> x.myAttr 'magic'   What's the magic? The goal of this, incidentally, is to cache calls to x.__getattr__().


I have a table that contains a list of metrics and their IDs in the format:  L6Metrics | ID   | Name            | -------------------------- | 734  | L6A_Velocity    | | 736  | L6B_Velocity    | | 738  | L6A_Target_Rate | ...   Each of these metrics has its own corresponding table containing timestamped historical data. If the metric has ID X, then its historical data's table name is History_tX. These history tables have the format:  History_t734 | DateTime                       | Value | ----------------------------------------- | 2018-05-04 19:17:41.972 -05:00 | 33.9  | | 2018-05-04 19:17:51.972 -05:00 | 36.3  | | 2018-05-04 19:18:01.972 -05:00 | 35.1  | ...   Assuming that the timestamps across all of the history tables align, how can I use the L6Metrics table to join all of the history tables on DateTime to get the following:  | DateTime                       | History_t734 | History_t736 | ... ----------------------------------------------------------------  | 2018-05-04 19:17:41.972 -05:00 | 33.9         | 34.9         | | 2018-05-04 19:17:51.972 -05:00 | 36.3         | 37.4         | | 2018-05-04 19:18:01.972 -05:00 | 35.1         | 36.5         | ...   There are 75 rows in L6Metrics (representing 75 history tables) so there would be 76 columns in my result. I have the ability to modify L6Metrics if needed.

I have a table called MyTable with varchar columns named SourceID and ReferenceID, where SourceID contains a table name and ReferenceID contains a key value for the source table. Is it possible in a query to refer to the source table's row assuming I know the name of the key column that matches the value in RefrenceID? Sample: SELECT     * FROM     MyTable as MT INNER JOIN MT.SourceID as Src ON MT.ReferenceID = Src.InstanceID  This doesn't work, obviously.  But is there a way to do this as opposed to dynamically building the SQL statement using the values of SourceID and ReferenceID and then executing the query?  More specifically, is there a way to make MyTable.SourceID in the example above be usable within the JOIN? Further considerations I found , and it has a trick like follows: select   E.EmployeeName, coalesce(s.store,o.office) as Location from   Employees E left outer join    Stores S on ... left outer join   Offices O on ... where   O.Office is not null OR S.Store is not null  The WHERE clause simply helps the outer joins behave like INNER JOINs.  This would work well enough if there were a limited number of table options and they all had UNIQUE constraints.  This gets me part of the way there but but I really want is to have the table names in the JOINs to be based on a column in Employees. I haven't given up yet. Any and all help is greatly appreciated.


I am stuck with this tutorial question in one of my stats module and I would greatly appreciate some help:  Let $X1$ and $X2$ be independent random variables with $a = 0$ and $b = 1$ i.e. $X1$ and $X2$ are uniformly distributed over 0 to 1.  How do you find the distribution function of $Y = X1 + X2$ for $1<y<2$ i.e. what is $F(y)$?

is there a general solution to that? I have seen simple examples for Y+X=Z but I was wondering how this would be with rescaling?


I'm wondering if there's an solid way (not a hack) to remove transparency from a photoshop layer? I know the usual, hacky way is to duplicate and merge a layer around 8 times or more to reach a fully opaque result (with the exception of areas with 100% transparency). But this just doesn't sound right, maybe there's an option to do this without such a convulted method that I don't know about.  Here's an example:

I have a semi-transparent monochrome image in a Photoshop document, that I would like to become fully opaque:    The opacity is already set to 100% in Blending Options, it's just that this image has an alpha channel that I would like to remove.  How can I do that?


I recently (about a month ago) bought a Dell XPS 8500 Desktop with UEFI enabled Windows 8 Pro pre-installed. I am trying to install Ubuntu 13.04 64-bit dualboot with Windows on this computer. I don't know much about UEFI, but I think I followed the correct instructions to do this installation. Here's what I've done so far:   I have a 256GB SSD drive with the Windows OS partition and a 1TB drive for data. I created a 100GB partition on the 1TB drive for ubuntu. This was done through Windows Disk Management. I downloaded Ubuntu and created a bootable USB as per the instructions on the Ubuntu website.  I tried installing Ubuntu through the USB.   PROBLEM: While installation, I do not see a "Install alongside Windows 8" option like I have usually seen in all my previous installs.   Now, I don't know if this has to do with UEFI and I don't know much about that anyway.   QUESTION: How should I proceed with the installation?  I am currently on the same computer through Windows. I also have access to a laptop with Windows 8 Pro (possibly not enabled with UEFI - it's an old computer with newly installed OS) alongwith Ubuntu 12.10 dualboot.   Let me also add that my Secure Boot is ON. I also tried it with SecureBoot OFF, but didn't work.  I followed all the steps mentioned here in order:    EDIT: I "tried" Ubuntu without installing it via the LiveUSB. It is not able to access any of the drives. Do you think that has anything to do with this issue? Any help would really be appreciated. Thank you so much.

I'm absolutely new to Linux. I would like to know how to install Ubuntu alongside the pre-installed Windows 8+ OS.  Should I do it with Wubi, or through the Live USB/DVD?  What steps do I need to take to correctly install Ubuntu?


This particular  seems to be on a tag wiki editing spree. I've noticed quite a few tag edits which are very trivial and offer very less information. And I happened to see quite a lot of the tag wiki edits in the reviews queue even today.  My question is, how do I flag such an user for moderator attention? Because there is no flag option in the review page of a tag wiki edit, nor does the tag page have an option to flag.

However, new features on the site may warrant a fresh look.  Specifically, suggested edits on tag wikis.  I've recently hit 10k on the main site and have been reviewing a lot of suggested edits.  Today I ran across  that seems to be making edits with spam content.  The ones I found today were for xml related tags in the tag wikis and the suggested content was about buying cheap shoes from china.  Previously the answer to this was "flag their posts!" which was very reasonable.  Now, however, users like this are able to cause issues without ever posting a question, answer, or comment to flag.  Does the ability to flag a user need to be added?  Alternatively, should we be able to flag suggested edits?  For clarification, here are the edits suggested by this user:  to the xml-parsing tag:      The US markets opened just minutes ago,china shoes wholesale now       let's cross over to our correspondent Natalie Carney in New York,   factory shoes wholesale cheap to see how it's reacting to the   downgrade.      Q1. It was pretty ugly today on from shoes wholesale the Asian   markets. And it doesn't look like Wall Street will be much better off   today, its first session since the downgrade. Tell us, how are   investors there reacting?      Q2. There's panic selling on the equity china wholesale markets, but   yields on US Treasury bonds have been moving rather modestly, though   the risks are supposed to be higher. Looking ahead, will Treasuries   remain a safe haven in all this uncertainty?      Website:  MSN: igshox@hotmail.com Yahoo:   Igshox@yahoo.cn   To the excerpt for the same tag:     How can I found the cheap shoes from china factory or chinese   wholesale supplier   EDIT TO CLARIFY:  This user only posted a suggested edit to a tag wiki and a tag wiki excerpt, and there is no way to flag those for moderator attention.


On the list of  the non-English Stack Overflow sites do not have a properly localized description   The Russian one should read as  Сайт вопросов и ответов для программистов  The Portuguese one should read as  Site de perguntas e respostas para programadores profissionais e entusiastas  I don't know Japanese, so I don't know what it should look like.

If you click the Stack Exchange site drop-down menu:        and look closely at the  menu item for "Русский язык", you'll see the following:      .   At the moment it is read as     "For лингвистов, этимологов, и энтузиастов русского языка"   Just two notes:   It is better to put "Для" instead of "For". According to rules, the comma before "и" is an error.   So, the whole line should be written as:      "Для лингвистов, этимологов и энтузиастов русского языка"


I've recently seen questions about the usage of "forget something somewhere".  The answer, as suggested in  is that the construction is commonly used and acceptable.   Actually reliable resources such as the  and the , for instance, clearly state that in the above mentioned construction the verb "leave" should be used instead of  "forget".   I am aware that the construction with forget is common and  that it is grammatically correct, but I don't understand why dictionaries and grammars warn against this usage.   Why is the construction " forget something somewhere"  considered "incorrect"?   EDIT: I don't think that this question is a duplicate as Mr. Hot Licks suggests. There is not the answer I am looking for in the other question.

Can you forget something somewhere?  I expect that much more common is      I have left my book at home.   But, based on other languages where it is quite common (and based on the fact that I somehow feel an intention hidden under the I have left), can you also use (in general, or GB/US/CA/AU specific) the following form?     I have forgotten my book at home.   If a pupil says the first sentence (with leave) in school, will the teacher interpret it as     I have intentionally left my book at home.   or      I have accidentally left my book at home.   ?


I'm using in my script:  tar cfh - "$SRC_DIR" --exclude-from <(find $SRC_DIR -size +$EXCLUDE_MB_FILES) | pigz -9 --quiet --keep --recursive --rsyncable > $BACKUP_TARGER_DIR/$ARC_NAME | tee $LOG_FILE   But LOG_FILE is empty. Why?

While using nohup to put a command to run in background some of content appear in terminal.  cp: error reading ‘/mnt/tt/file.txt’: Input/output error cp: failed to extend ‘/mnt/tt/file.txt’: Input/output error   I want to save that content to a file.


I just had a vacuum packed spiral ham delivered from the grocery. It was in the shade and outside temp in the '80s. It sat out there for right at 2 hours. It was still cool to chilly to the touch. Is it most likely to be good, or bad? It's killing me to throw that money away but I need know what's what here.

If I left food out of the refrigerator for some period of time, is it still safe? If I left it out too long, can I salvage it by cooking it more?


Problem Summary  I have two network interfaces in the machine, and need them to behave in the following way:   enp3s0: Main network interface for the machine.  Receive over DHCP an IP address (will be in 172.16.0.0/24), a gateway, and a DNS resolver for the office network and the world at large.  Default route is to this received gateway. enp2s0: Local subnet consisting of nothing more than 2 meters away, and nothing that should have access to the main network.  Serve DHCP on this network (192.168.0.0/24, domain is .localnet), and provide the local machine with DNS resolution of .localnet clients.   I had a working solution for all this under 16.04 using /etc/network/ and dnsmasq (no NetworkManager), but I'm just lost in the new era of netplan and systemd-resolved.  Everything just keeps fighting everything else.  So, what's my right, modern solution to make this work right?  Ideally in such a way that I won't have to change it for 20.04.  Additional information  For reference, here is the script that did what I needed under 16.04.  #!/bin/bash # # Configure the PC to use dual network adapters. # # usage: dualnetwork.sh <hinetif> <localnetif> # # This configuration is based around the use of the classic ifupdown # configuration files rather than NetworkManager.  This is substantially # more stable and easier to work with.  It is probably prudent to also # uninstall NetworkManager once this is done: #   sudo apt-get remove network-manager # # Must run as root. # # Rob Gaddi, 29 Jan 2019  GENERATED="Generated by $0 at $(date)" HINET=$1 LOCALNET=$2  abort () {     echo $*     exit 1 }  [[ ! -z "$LOCALNET" ]] || abort Must provide hinet and localnet interfaces. ip -br addr | grep $HINET    || abort Interface $HINET not found ip -br addr | grep $LOCALNET || abort Interface $LOCALNET not found  #################################################################### echo Configuring network interfaces #################################################################### mkdir -p /etc/network/interfaces.d echo source-directory /etc/network/interfaces.d > /etc/network/interfaces cat <<-CONF > /etc/network/interfaces.d/hinet     # $GENERATED     auto $HINET     iface $HINET inet dhcp CONF cat <<-CONF > /etc/network/interfaces.d/localnet      # $GENERATED     allow-hotplug $LOCALNET     iface $LOCALNET inet static         address 192.168.0.20/24      iface $LOCALNET inet static         address 192.168.254.20/24 CONF  #################################################################### echo Installing and configuring dnsmasq #################################################################### apt-get install --reinstall -y dnsmasq mkdir -p /etc/dnsmasq.d cat <<-CONF > /etc/dnsmasq.d/dualnetwork.conf     # $GENERATED     no-negcache     dhcp-range=192.168.0.100,192.168.0.150,4h     interface=$LOCALNET     domain=localnet     dhcp-fqdn     log-dhcp CONF systemctl enable --now dnsmasq.service   Edit  This differs from  in that the problem is not netplanning the machine IP addresses; that part is pretty easy.  The problem is making the system serve DHCP on one network.  When I tried it the obvious way, dnsmasq and systemd-resolved kept stepping on one another's toes.  When I tried just disabling systemd-resolvd and letting dnsmasq do all the work it never got the upstream DNS server when it accepted the main network DHCP.

I am new to the netplan on Ubuntu 18.04, just discovered it exists today. I have an interface that I am trying to add to create a floating IP on google cloud. It is based on this example:   I tested the example, and it works, but now I try to do the same on ubuntu, and I don't know how to convert this:  cat << EOF >> /etc/network/interfaces auto eth0:0 iface eth0:0 inet static     address 10.190.1.1     netmask 255.255.255.255 EOF   to netplan.  The output for ls /etc/netplan is '50-cloud-init.yaml'. and the output for cat /etc/netplan/*.yaml is:  network:     version: 2     ethernets:         ens4:             dhcp4: true             match:                 macaddress: 42:01:0a:8e:00:3e             set-name: ens4   my ifconfig:  # ifconfig  ens4 ens4: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1460     inet 10.142.0.62  netmask 255.255.255.255  broadcast 0.0.0.0     inet6 fe80::4001:aff:fe8e:3e  prefixlen 64  scopeid 0x20<link>     ether 42:01:0a:8e:00:3e  txqueuelen 1000  (Ethernet)     RX packets 9430  bytes 1635180 (1.6 MB)     RX errors 0  dropped 0  overruns 0  frame 0     TX packets 13383  bytes 1513428 (1.5 MB)     TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0   What is the equivalent of what he said to put in the file, for netplan?


So, let $K$ be an algebraic closure of $\mathbb{F}_{p}$ and consider the space $V=K\otimes_{\mathbb{F}_p}\mathbb{F}_{p^n}$ as a $K$ vector space. It seems pretty straight forward to show that this vector space is $n$ dimensional since for $\{\alpha_1,\ldots\alpha_n\}$ linearly independent elements of $\mathbb{F}_{p^n}$ (considered as itself a vector space over $\mathbb{F}_p$) we have the linearly independant tensors $1\otimes\alpha_i$. Then I think it is clear that any elementary tensor is a $K$ linear sum of these and so these must span $V$.   Anyway, what I don't understand is in what way this vector space is practically different from simply considering $\mathbb{F}_{p^n}$ as a $\mathbb{F}_p$ vector space.  Studying for my algebra qualifying exam, I worked on a problem that asked to calculate the basis for $V$ for which the Froebenius automorphism is in Jordan canonical form. I don't see how this is different from doing it for $\mathbb{F}_{p^n}$.  Although, we know a priori that the form exists since the underlying field is complete algebraically closed, but isn't that true for $\mathbb{F}_{p^n}$?  Thanks.

Let $\phi(x) = x^p$ be the Frobenius automorphism on $\mathbb F_{p^n}$. We can view $\mathbb F_{p^n}$ as an $n$-dimensional vector space over $\mathbb F_p$. In this case, $\phi$ is a linear transformation. What are its characteristic and minimal polynomials? What are its Jordan and rational canonical forms? I know that $\phi$ satisfies $x^n - 1$, so its minimal and characteristic polynomials must divide this one. But, I can't seem to make much progress beyond this. Any suggestions?


I model a car and I want to make a rooftop first of all. I would like to make it like this:    How to evenly space the edges to make what I want?

I have a edge loop that has vertices on it. Is there a way I can separate the vertices on the the edge evenly without moving the end points? I would also like for the vertices to maintain the current shape.


I am trying to insert some text in a file in the following way  sudo echo "abc-abc/abc/abc" >> /etc/portage/make.conf   but it give me the error Permission denied   although I am using sudo command

When you attempt to modify a file without having write permissions on it, you get an error:  > touch /tmp/foo && sudo chown root /tmp/foo > echo test > /tmp/foo zsh: permission denied: /tmp/foo   Sudoing doesn't help, because it runs the command as root, but the shell handles redirecting stdout and opens the file as you anyway:  > sudo echo test > /tmp/foo zsh: permission denied: /tmp/foo   Is there an easy way to redirect stdout to a file you don't have permission to write to, besides opening a shell as root and manipulating the file that way?  > sudo su # echo test > /tmp/foo


General Parker orders a curfew citywide to reduce crime rate.  While curfew is on effect, General Parker's soldiers caught a violator and took him to detention center.  While in detention center, the other inmates ganged up on the violator and beat him, up. And he died.  Therefore, General parker's is to be blame, since the violator wouldn't have died if he didn't end up in a detention center because of the curfew

I would ask if this is a logical fallacy, but I don't think you can consider wrongful attribution of blame to be a logical fallacy, because attributing blame is a normative claim, not a descriptive one.  Suppose an event happens. Looking back at the chain of events, we see that person A did an action such that, had this action not occurred, the event would not have happened. We then blame person A for the event, and hold them morally responsible.  For example, suppose I have a gambling problem. Because of this problem, I steal money from my cousin's wallet and gamble it away. This triggers my cousin, who cares about me, to search for a gambling anonymous group for me to join. He finds one and drives over there. In the parking lot of the site, he gets accosted by a mugger who attacks, and essentially kills him. Now my family blames me and my gambling problem for my cousin's death.  Clearly it's true that, in an indirect way, my action caused my cousin to die. But it's a misattribution of blame to say that I'm morally responsible for my cousin's death based on my action. It would, however, be appropriate to say that I'm morally responsible for the loss of my cousin's money.  I believe that this is such a common error in argumentation that there must be a term for it.