I am confused as to what this question is asking me to do. For context, hello is a c++ file.     "Use chmod command again to make hello an executable, but not readable   and not writeable for all users."   Using an online chmod calculator, my best guess would be chmod 001 hello, which is executable by the public, but not readable nor writeable by the public.   Is this correct?

I've never really got how chmod worked up until today. I followed a tutorial that explained a big deal to me.   For example, I've read that you've got three different permission groups:   owner (u) group (g) everyone (o)   Based on these three groups, I now know that:   If the file is owned by the user, the user permissions determine the access. If the group of the file is the same as the user's group, the group permission determine the access. If the user is not the file owner, and is not in the group, then the other permission is used.   I've also learned that you've got the following permissions:   read (r) write (w) execute (x)   I created a directory to test my newly acquired knowledge:  mkdir test   Then I did some tests:  chmod u+rwx test/ # drwx------ chmod g+rx test/ # drwxr-x--- chmod u-x test/ # drw-r-x---   After fooling around for some time I think I finally got the hang of chmod and the way you set permission using this command.    But...  I still have a few questions:   What does the d at the start stand for? What's the name and use of the containing slot and what other values can it hold? How can I set and unset it? What is the value for this d? (As you only have 7=4+2+1 7=4+2+1 7=4+2+1) Why do people sometimes use 0777 instead of 777 to set their permissions?   But as I shouldn't be asking multiple questions, I'll try to ask it in one question.  In UNIX based system such as all Linux distributions, concerning the permissions, what does the first part (d) stand for and what's the use for this part of the permissions?


I'm relatively new at c++ programming so bear with me if I make any common mistakes.  I have a string that looks like this:  String str = "[abc, abcde, lkejs, abde], [123, 456, 7890]"   I wish to store each of those values into a vector such that it looks something like:  abc abcde lkejs abde 123 456 7890   I've read up on and tried using Boost tokenizer but I'm restricted from installing new libraries into the operating system which this code is supposed to be run.  I've also tried strtok() but that just confuses me even further as it converts my entire string into chars.  Looking through  , I probably would be better off using string::find_first_of() but the examples available there aren't doing much in helping me understand how it works.  Can anyone help me understand the syntax of string::find_first_of() better or is there a better way of splitting strings without the need to install additional libraries like boost does?

I'm trying to iterate over the words of a string.  The string can be assumed to be composed of words separated by whitespace.  Note that I'm not interested in C string functions or that kind of character manipulation/access. Also, please give precedence to elegance over efficiency in your answer.  The best solution I have right now is:  #include <iostream> #include <sstream> #include <string>  using namespace std;  int main() {     string s = "Somewhere down the road";     istringstream iss(s);      do     {         string subs;         iss >> subs;         cout << "Substring: " << subs << endl;     } while (iss); }   Is there a more elegant way to do this?


So when deriving the LK form of the exact propagator he says (chapter 13): $$ \langle 0| \phi(x)\phi(y)|0\rangle=\int d\tilde k e^{ik(x-y)}+\int_{4m^2}^\infty ds\rho\int d\tilde ke^{ik(x-y)}. \tag{13.12}$$ My question is about the $4m^2$ cutoff, I get that this is the 2 particle mass, however, that is only true if they don't interact.  Surely there will be either some bound states just below that or, depending on if the particles attract or repel, this cutoff will be shifted? Does he just mean this approximately or am I missing something?

Consider a  $\phi(x)$, and let its  be $$ \frac{1}{p^2-m^2-\Pi(p^2)}=\int_0^\infty\mathrm d\mu^2\ \rho(\mu^2)\ \frac{1}{p^2-\mu^2} $$  We usually have $\Pi(m^2)=0$, which implies that there is a one-particle state with mass $m^2$. In terms of the , this reads $$ \rho(\mu^2)=\delta(\mu^2-m^2)+\sigma(\mu^2) $$ where the support of $\sigma(\mu^2)$ is disconnected from $m^2$.  On the other hand, the continuum contribution usually begins at $(2m)^2$, meaning that $\Pi(k^2)$ has a branch cut from $(2m)^2$ to $\infty$. Again, in terms of the spectral function, this is written as $\text{supp}(\sigma)=[(2m)^2,\infty)$.  My question  I would expect that the first bound state to lie close to $(2m)^2$, but slightly below, something around $(2m)^2-\mathcal O(\alpha^n)$, where $\alpha$ is the coupling constant and $n\in\mathbb N$. For example, in a simplified QED model, the bound state of an  has binding energy $\sim 7\mathrm{eV}\sim m\alpha^2$, and so I would expect the branch point to be somewhere around $(2m)^2-m^2\alpha^4$.  I know the value of the self-energy to one loop, and the branch point is indeed exactly at $(2m)^2$. I don't know where to find higher loop corrections, so I cannot conclude whether   1) at higher loops, the branch point moves a bit closer to $m^2$, or 2) it stays at $(2m)^2$.   I would expect that the correct behaviour is 1), but this contradicts the fact that all books I've read always depict the threshold of pair production as an hyperboloid with its bottom sitting exactly at $(2m)^2$. On the other hand, if it turns out that the correct option is 2), I am lead to ask why is perturbation theory unable to correctly predict the position of the branch point (I know this is a subtle issue because bound states are, to some extent, non-perturbative entities; but AFAIK, perturbative calculations do contain a lot of information about bound states).


Simplify $0 \binom{n}{0} + 1 \binom{n}{1} + 2 \binom{n}{2} + \dots + n \binom{n}{n},$ where $n \ge 1.$ Enter your answer in the form $f(n) 2^{g(n)},$ where $f(n)$ and $g(n)$ are polynomials in $n$ with integer coefficients. I know that $$\binom{n}{0} + \binom{n}{1} + \binom{n}{2} + \cdots + \binom{n}{n} = 2^n .$$ But I'm not sure how to find the answer if there are numbers multiplied to each of the binoms.

I am trying to prove this binomial identity $\sum_{r=0}^n {r {n \choose r}} = n2^{n-1}$ but am not able to think something except induction,which is of-course not necessary (I think) here, so I am inquisitive to prove this in a more general way.  The left side of an identity occurs while solving another problem (concerning binomial theorem) so I am more interested in deriving the right side from the left side, else I have to remember it now onward.  EDIT: I am more interested in an algebraic proof rather than combinatorial argument or something involving calculus (however I liked  and  solution), hence I am removing the combinatorics tag.


I am new to the scheme language and one of the things the professor talked about was tail recursion. I didn't quite get it. Can someone please explain to me in detail what is meant by tail recursion and how it differs from normal recursion?  Also, does anyone have any idea on how For-loop and Which-Loop were implemented in languages like C++, Java etc. This part is just for curiosity purposes.  Thanks

Whilst starting to learn lisp, I've come across the term tail-recursive. What does it mean exactly?


I have this text on a white bar in Illustrator, and I would like to make that part of the white bar transparent instead of what it currently is - the same color as the background.  I tried doing the clipping mask, but it does the opposite, it gets rid of the white bar and makes the text white  Can anyone offer any suggestions?    when I then try to make a compound path, the 2015 converts fine, but there is another compound path that I try to do this to and it does not work, and it also distorts some of the letters:

My enterprise logo has the text Job overlapping a bag icon. What I really want to achieve is a white bag logo with the text punched out. That way, on any background the text has the color of that background. Compare the facebook icon with the dark-blue border.       The error it gave me    The bag issue.


Im not THAT experienced in Blender Python but i think this is something confusing.c I want to use multiple files for an addon and im not able to. I dont understand what am i supposed to do Am i supposed to just import the class in init and do nothing with it and register it in the same file as the class , or am i supposed to register the classes in the init even if i do one of them , the relative import doesnt work if i do from .AddCube import * it says ImportError: attempted relative import with no known parent package Error: Python script failed, check the message in the system console

I'm trying to put together an add-on that contains two operators.  I've gotten each operator file to run properly independently, but I'm having trouble figuring out how to write an init.py file that would allow me to distribute them as a single add-on.  I've posted everything on Github.  The three files aren't too long:   I've read a few other threads, but nothing seems to work for me.  How can I get my init.py to register my operators properly?


So by X-Men: Days of Future Past, the X-Men timeline is reset. So, Wade never met Stryker and was never made into Mutant-XI who went to fight Wolverine. Then why did Deadpool go back in time to kill him in front of Wolverine?   I know it was funny, but really confuses me about the timeline of the X-Man movies.

When did the events of Deadpool take place in the X-Men timeline?  Surely Deadpool takes place in a quite recent time era as compared to First Class and it's sequel, but exactly where?


What is the solution of this kind of exercise $A=\sin2a+\sin4a+\ldots+\sin10a$  I have already tried to multiply with $2\cos \frac a2$ to solve this.

How can we sum up $\sin$ and $\cos$ series when the angles are in arithmetic progression? For example here is the sum of $\cos$ series:  $$\sum_{k=0}^{n-1}\cos (a+k \cdot d) =\frac{\sin(n \times \frac{d}{2})}{\sin ( \frac{d}{2} )} \times \cos \biggl( \frac{ 2 a + (n-1)\cdot d}{2}\biggr)$$  There is a slight difference in case of $\sin$, which is: $$\sum_{k=0}^{n-1}\sin (a+k \cdot d) =\frac{\sin(n \times \frac{d}{2})}{\sin ( \frac{d}{2} )} \times \sin\biggl( \frac{2  a + (n-1)\cdot d}{2}\biggr)$$   How do we prove the above two identities?


I currently use Ubuntu 13.04 on LG X110 notebook After last updating (on 28th August 2013) software doesn't work. It suddenly stops while I'm using it. Hardware still runs: I know because of the noise, but noise it has during doing no operation. Software doesn't work at all: desktop is frozen, mouse is blocked, any keyboard command gives no result.  I already uninstalled Xubuntu, in case there was some bug with it, but it just doesn't matter.  Any suggestion?

All operating systems freeze sometimes, and Ubuntu is no exception. What should I do to regain control when...   just one program stops responding? nothing at all responds to mouse clicks or key presses? the mouse stops moving entirely? I have an    In what order should I try various solutions before deciding to pull the power plug?  What should I do when starting up Ubuntu fails?  Is there a diagnostic procedure I can follow?


I used PCA to project 4 dimensions to 2 dimensions. All the values were positive, but PCA gave me negative values.   I wonder if the negative only means correlates negatively with the axis.

I performed principal component analysis (PCA) with R using two different functions (prcomp and princomp) and observed that the PCA scores differed in sign. How can it be?  Consider this:  set.seed(999) prcomp(data.frame(1:10,rnorm(10)))$x              PC1        PC2  [1,] -4.508620 -0.2567655  [2,] -3.373772 -1.1369417  [3,] -2.679669  1.0903445  [4,] -1.615837  0.7108631  [5,] -0.548879  0.3093389  [6,]  0.481756  0.1639112  [7,]  1.656178 -0.9952875  [8,]  2.560345 -0.2490548  [9,]  3.508442  0.1874520 [10,]  4.520055  0.1761397  set.seed(999) princomp(data.frame(1:10,rnorm(10)))$scores          Comp.1     Comp.2  [1,]  4.508620  0.2567655  [2,]  3.373772  1.1369417  [3,]  2.679669 -1.0903445  [4,]  1.615837 -0.7108631  [5,]  0.548879 -0.3093389  [6,] -0.481756 -0.1639112  [7,] -1.656178  0.9952875  [8,] -2.560345  0.2490548  [9,] -3.508442 -0.1874520 [10,] -4.520055 -0.1761397   Why do the signs (+/-) differ for the two analyses? If I was then using principal components PC1 and PC2 as predictors in a regression, i.e. lm(y ~ PC1 + PC2), this would completely change my understanding of the effect of the two variables on y depending on which method I used! How could I then say that PC1 has e.g. a positive effect on y and PC2 has e.g. a negative effect on y?    In addition: If the sign of PCA components is meaningless, is this true for factor analysis (FA) as well? Is it acceptable to flip (reverse) the sign of individual PCA/FA component scores (or of loadings, as a column of loading matrix)?


Can we restrict a user and do not let him to go to the root mode. For example, when he inter sudo su, The system tells him you can not access the root?

If you give a user sudo privileges how can I remove the sudo privileges and make the user become just a regular user?  I used:  sudo adduser username sudo   Now I've changed my mind.


Midpoint convexity. A set C is midpoint convex if whenever two points a,b are in C, the average or midpoint (a + b)/2 is in C.Prove that if C is closed and midpoint convex, then C is convex.   Convex set means that $\forall x_1, x_2 \in C, \theta x_1+(1-\theta)x_2 \in C \forall \theta \in[0,1]$  I know  $$ \left(x_1+x_2\right)/2 \in C \implies \dfrac{x_1+\dfrac{x_1+x_2}{2}}{2}= \dfrac{x_1}{2}+\dfrac{x_1}{4}+\dfrac{x_2}{4} = \dfrac{3}{4}{x_1} +  \dfrac{1}{4}{x_2} \in C $$ Applying this k times I get the following: $$ (1-2^{-k})x_1+2^{-k}x_2=(1-\theta_k)x_1+\theta_k x_2 \in C $$  but I have showed it only for $\theta$ values that takes the form of $2^{-k}$ where $k \in N$  What should I do next?

Given that $$f\left(\frac{x+y}{2}\right)\leqslant \frac{f(x)+f(y)}{2}~,$$ how can I show that $f$ is convex. Thanks.      Edit: I'm sorry for all the confusion. $f$ is assumed to be continuous on an interval $(a,b)$.


The Sun bends planet's trajectory and speeds up it towards the perihelion; does it both actions with light? If it speeds up light too, then does it mean that gravity is a consequence of a vortex that transports massive objects, as well as light vibrations, like a highway does to vehicles? I read an answer on PSE site about the vortex-like effects of a star to two identical masses, where these masses have different net velocities when moving at a same distance around that star, one in direction of the possible vortex and the other in counter direction of the vortex.

We know that gravity speeds up a body; for instance, a meteor which enters the earth gets constantly accelerated up by earth's gravity. And from relativity we know that light bends near a massive body, because Newton's law of gravitation is just an approximation and actually gravity depends on energy and momentum. So my question is: If a ray of light is aimed exactly at the center of a body, then will it get accelerated like a meteor? And if does get accelerated, then won't it surpass the universal speed limit of 3,00,000 km/s (approx.)?


I'm new to photography and just starting to take photo in RAW format. I haven't found a difference in quality of color adjustment editing between ViewNX (free software coming with my Nikon d5100) and Picasa, perhaps because of my inattentiveness. So I've decided to ask here what is the best free software to get most from RAW (Nikon NEF) photo editing?

I'm looking for a free RAW editor/converter on Windows. Can you tell me some strong/weak points of them comparing with Capture NX and/or Adobe Photoshop Elements?       - conversion & EXIF  - white balance  - registration not possible anymore   EXIF editing would be a nice bonus.  Related:


Lets say i powered a led strip rated at 5V and 3.6A by my laptop usb port via usb cable, what will happen?  -will it just be limited to 900mA since thats max current for usb 3.0  -or will it try draw out 3.6A from the usb port and break it  extra: what if i wired the led strip to an arduino that has a max current of 1A  and powered it with usb port, what will happen then?

One of the products being shown a CES is a  intended to let you charge a tablet from a laptop USB port that normally wouldn't work because it didn't provide enough power.  The CNET writeup implies that it's actually boosting the power output from the port beyond the normally available amount.  This seems improbable to me because the ports should have current protection to protect themselves from shorts.  Also, if it was possible to bypass the current limit externally, I'd've expected at least some tablet vendors to have included the ability to do so directly in their cables.  One possibility that occurs to me is that the dongle is just spoofing responses to the tablet when it queries the laptop about the maximum power it can deliver while only providing a trickle charge that the tablet would otherwise reject as too slow to bother with.


I know that $\sum_n U_n$ is cgt therefore $\underset{n}{\lim} U_n = 0$ and by definition of limit $0- \varepsilon < U_n < 0+\varepsilon$ for all $\varepsilon > 0$ but I don't know how to get to $\sum_nU_n^2.$  P. S.  Here $\sum_nU_n$ is series of positive terms.

My attempt runs as follows. Since $\sum |a_{n}|$ converges, the series $\sum a_{n}$ converges. Since $a_{n}^{2} \geq 0,$ it suffices to prove that there is an $M > 0$ such that $$\sum_{1}^{m}a_{n}^{2} < M$$ for $m \geq 1.$ But, since $\sum a_{n}$ converges, there is a $B > 0$ such that $$\sum_{1}^{m}a_{n} < B$$ for $m \geq 1,$ so $$(\sum_{1}^{m}a_{n})^{2} = \sum_{1}^{m}a_{n}^{2} + 2\sum_{j < k}a_{j}a_{k} < B^{2}$$ for $m \geq 1.$  However, the problem is there seems no way to determine whether the sum $\sum_{j < k}a_{j}a_{k}$ is positive or negative?


My bf and I are traveling for a wedding in Oct. We planned on driving from phoenix to mexicali and flying from there to Guadalajara.   My questions are: can we use our drivers license to get into Mexicali or should we get the passport card? Trying to avoid getting the book it is expensive for us.   Also, once in Mexicali, do we NEED the passport card to fly to Guadalajara or can we just use our ID and the tourist card? We will be there about 4 days.

I am a U.S citizen. Do i need a passport and visa when flying from California to Guadalajara. I do not have a passport and I will only be visiting Guadalajara for 4 days on business.


I maxed out my Werewolf perks and did all three Totem quests for Aela, so I wanted to get rid of my lycanthropy.  Simply going to Ysgramil with a Glenmoril's Witches head doesn't work, I can press the "Activate" button near the blue flames all I want, but it doesn't work. Several sources said that to be able to cure your own lycanthropy you had to start the quest "Purity" for either Vilkas or Farkas.  After a couple of radiant quests with two Witches' heads in my inventory Vilkas finally asked me to help him find a cure for his lycanthropy and he starts following me around for this quest. As soon as I leave Jorrvaskr, however, he says a random line and goes back inside. The quest is suddenly moved to my finished quests log, without it registering as either Completed or Failed...  I reloaded the autosave in Jorrvaskr and got the quest again, this time asking Vilkas to follow me. He said I already have a follower (which should be him) yet the quest was moved to my finished log again, this time without even leaving Jorrvaskr. Talking to Vilkas again led to him giving another radiant quest.  What else can I do?  Perhaps on a related note; Farkas won't give me any radiant quests whatsoever, so I can't cure him at all.

I really want to get rid of it. I've been through the whole companion’s quest line and cured Kodlak's. I killed all 5 witches and have 4 of the heads left in my inventory.  I've been back to that same flame and tried to use it with the head, but nothing going; activating it does nothing. I've heard this is how you cure it; however I have not heard a first-hand account of anyone actually curing it.  If you have, can you explain what you do? Do you go to the same tomb where you fought Kodlak's beast form? Do you do something special with the witch head in your inventory, or just have it in there and activate the harbinger flame or whatever?


I'm trying to dynamically set some text in an input field, and then display it, and finally auto-highlight/auto-select it.  If I don't use .val() and instead use value="something" hardcoded on the input it works perfectly.  If I add .val() to the method chain, it just puts the cursor in the box but doesn't highlight the text.  Any idea how I might do this?  In the example below, $(this) refers to the link they click on "Rename" which causes inline edit box to appear. The .next() refers to the input.  $(this).hide().next().val(oldName).show().focus();

What is a Vanilla JS or jQuery solution that will select all of the contents of a textbox when the textbox receives focus?


I installed Ubuntu and realized that some programs weren't compatible with Linux. I tried Wine but it didn't help, it still supported nothing. So, I decided to dual boot Windows. I went to disks on Ubuntu and formatted the flash drive. Restarted and- NOPE. It wasn't a bootable drive. How can I find a ISO burner that makes bootable on Ubuntu that burns Windows ISOs and not just Linux distros?

I'd like to create a Windows bootable USB stick, but I don't have a Windows machine with me at the moment to do so. How could I achieve the same using Ubuntu?


I want to calculate the Fourier Cofficient for the function defined by: $$f(\theta) =\frac {(\pi - \theta)^{2}}{4}$$ for $0 \leq\theta \leq 2\pi.$  but the definition for the Fourier Coefficient is from $-\pi$ to $\pi$ for the functions that is integrable on this interval.So, in my function shall I change  the boundaries in the definition of the Fourier Coeffient to be from 0 to $2\pi.$  But I do not think so because if I do this then I found that  $$\hat{f}(0) = \frac{\pi^{2}}{4}$$  But it is answered in the book as:$$\hat{f}(0) = \frac{\pi^{2}}{12}$$   Could anyone give me an advice?   thanks.

According to p. 36 of Stein and Shakarchi's Fourier Analysis, the Fourier series is $\frac{\pi^2}{12} + \sum_{n=1}^{\infty} \frac {\cos{n\theta}}{n^2}$.   But to calculate the Fourier coefficients, I computed $\int_{-\pi}^{\pi}\frac{(\pi-\theta)^2}{4}e^{-in\theta}d\theta = \frac {1} {4} \Bigg[\frac{4\pi^2e^{in\pi}}{in}-\frac{2}{in}\int_{-\pi}^{\pi}e^{-in\theta}(\pi-\theta)d\theta\Bigg]=\frac {1} {4}\Bigg[\frac{4\pi^2e^{in\pi}}{in}-\frac{4\pi{e^{in\pi}}+2e^{-in\pi}-2e^{in\pi}}{n^2}\Bigg]=\frac{\pi^2ne^{in\pi}+\sin{n\pi}}{in^2}$  This means the Fourier series is $\sum_{n=-\infty}^{\infty}\frac{\pi^2ne^{in\pi}+\sin{n\pi}}{in^2}e^{in\theta}=\sum_{n=-\infty}^{\infty}\frac{\pi^2e^{in(\pi+\theta)}}{in}+\frac{e^{in(\theta-\pi)}}{2n^2}$, but I can't seem to  get this to equal that simple thing from the book.  Can anyone help?


I am a Ghanian and am a Canadian permanent resident. Can I transit without a visa through the UK and any EU country on my way to Ghana (such as Amsterdam, Belgium, Italy, Germany)?

Is there a website or some other way to find out if I need a transit visa for a short stop in the UK on my way somewhere else? Ideally this should give me the answer for all nationalities, and take into account any other visas I may have.


I'm looking for a way to have automated period padding for some items I'm discussing in my proposal. For example:  Pneumatic Drill.......................$450.12  Drill Bit.....................................$12.90    Ideally, I'm looking for something like the following I suppose:  \noindent\hspace{0.45cm}\dag\hspace{0.25cm}\begin{period-padder}\$450.12\end{period-padder}

I would like the whitespace between two items within a table to be filled with dots.  Please consider the following picture to get the idea.    So far I tried to achieve this output with the following sequence.  %!TEX TS-program = xelatex %!TEX encoding = UTF-8 Unicode \documentclass[10pt]{article} \usepackage{booktabs}  \begin{document}  \begin{table}[!htbp]  \begin{tabular}{lrrr}         \toprule     Anzahl & Behandlungstyp & Einzelpreis & Gesamtpreis\\         \midrule     10\dotfill& Manuelle Therapie\dotfill & €32,63\dotfill & €326,30\\     10\dotfill &Krankengymastik\dotfill &€26,93\dotfill &€269,30\\         \bottomrule     \end{tabular}  \end{table}  \end{document}   This, however, yields an unsatisfactory output, where undotted gaps are left over.   How to achieve a continuous dotted line without white spaces like in the first picture?


Ubuntu 16.04 I created a swap file using:  sudo mkdir -v /var/cache/swap cd /var/cache/swap sudo dd if=/dev/zero of=swapfile bs=1K count=4M sudo chmod 600 swapfile   sudo mkswap swapfile sudo swapon swapfile echo "/var/cache/swap/swapfile none swap sw 0 0" | sudo tee -a /etc/fstab   After rebooting, i tested using  sudo swapoff swapfile sudo swapon -va   Everything at this point seems to be fine. But after I ran ecrypt following the  on the home folder, trying  sudo swapoff swapfile swapoff: swapfile: swapoff failed: No such file or directory   Also, when I do:  sudo swapon -va swapon: cannot open /dev/mapper/cryptswap1: No such file or directory   At this point, I'm attempting to just remove this swapfile that I just created. I tried to stop it by going straight to /var/cache/swap and try swapoff:  /var/cache/swap$ sudo swapoff swapfile swapoff: swapfile: swapoff failed: Invalid argument   Why the invalid argument? I just want to know if it's safe to just manually remove the manually-created swap directory without swapoff, and then make an encrypted swapfile. Thanks.

When I installed Ubuntu, I setup an encrypted home partition. Now I have come to an issue where I am running out of memory because I haven't setup swap. How can I setup an encrypted swap file?  A couple of times while booting I've seen some reference to cryptswap. I've also got these lines contained in /etc/fstab  # swap was on /dev/sda6 during installation #UUID=1ba8a53b-1842-4de7-8e38-2d6c79f3a1ab none            swap    sw              0       0 /dev/mapper/cryptswap1 none swap sw 0 0


When one types on the keyboard in a view of a directory in nautilus, it either starts searching or to select the first file/folder matching the input with a prefix in the file's/folder's name. I've been searching a availalbe options in the settings dialog, but it doesn't seem to be configurable and change from release to release (in Ubuntu 14.10-beta1 it's searching, in 14.04 it was prefix matching and in 13.10 searching again, as far as I remember). How to configure prefix matching?

Until now I was using a "traditional" version of Nautilus: that that comes with Ubuntu 10.10. Now I'm using 3.6.3, included with Ubuntu 13.04 (most likely any recent version is equivalent for the scope of my question, anyway).  One major difference between the two is the search-as-you-type behavior: in classic versions of Nautilus, when you typed an input, the file with the closest alphabetical match would become the selected one, the eligible files/folders being restricted to the current directory.  The new behavior is to perform an optionally-global search instead.  Can one configure Nautilus to provide the previous functionality ?


Application on the Linux server is using several large files of 10-20 GB in size. It is constantly writing and reading on all of them, I want to see usage details: which file is under heavy use, see bandwidth, operation count etc. Is there a way to do that?

I am interested in a utility or process for monitoring disk IO per file on CentOS.  On Win2008, the  utility allows this type of drilldown, but none of the Linux utilities I have found do this (iostat, iotop, dstat, nmon).  My interest in monitoring IO bottlenecks on database servers. With MSSQL, I have found it an informative diagnostic to know which files / filespaces are getting hit the hardest.


I have lots of apps on my iPad and I want to copy them to my PC, usually I'd just click transfer purchased in iTunes but now it's not working. I want to backup and restore my iPad because I've been having some issues. iFunBox isn't working either

After upgrading to iOS 9, I can't transfer purchases from my iPhone to iTunes. It happens to just start the process, then it finishes without transferring anything. However, I can still transfer purchases from my iPad with iOS 8.4 like before.   iPhone 5c, iOS 9 iTunes 12.3 MacBook Pro 13" with Retina Display Mid 2014, OS X El Capitan   Apparently, not many people happen to use this "transfer purchases" feature so it didn't get any real attention. I used it a lot, I used to update my apps on my iPhone, transfer them to iTunes and updated my iPad apps using iTunes. Still, I can update my apps using iTunes and update apps on all my devices.


Sorry, if this question is trivial...  There are two ways of initializing fields  For example:  The first way is:  Public class A{     int a;     A(){         a = 5;     } }   The second way is:  Public class A{     int a = 5;     A(){     } }   Which way is better? Why or why not?

I've been programming in C# and Java recently and I am curious where the best place is to initialize my class fields.  Should I do it at declaration?:  public class Dice {     private int topFace = 1;     private Random myRand = new Random();      public void Roll()     {        // ......     } }   or in a constructor?:  public class Dice {     private int topFace;     private Random myRand;      public Dice()     {         topFace = 1;         myRand = new Random();     }      public void Roll()     {         // .....     } }   I'm really curious what some of you veterans think is the best practice. I want to be consistent and stick to one approach.


Instead of the usual "select a location from what you see", I need to type a path to reach a file a I need to open.  Where can I type locations (paths) in this dialog?

After running software updater, the path bar in the file dialog (for example the one you get when choosing Open File in in Google Chrome or Firefox) is missing. This is frustrating since it's no longer possible to copy a path from the terminal (for example) and paste it into the file dialog. Here is a screenshot of the dialog:     How can I get back the path bar?


I am using Microsoft RDP on my OS X in order to control the Windows PC inside my local network. The two computers are connected via a 1Gbps Ethernet router, so the bandwidth shouldn't be a bottleneck. However, I find that the frame rate of RDP is not so satisfactory. Both the frame rate and image quality are very low when watching videos or running graphical programs. According to inspections, I found that the RDP is only using a few MB/s of the bandwidth which is far from full. So why it cannot make full use of the network bandwidth and provide promising quality and frame rate so that I can control it through the LAN as I were directly using it?

I am using a Windows 10 PC and I want to access and control it using my iPad. So I installed Microsoft Remote Desktop on my iPad. The problem is that when I play videos in remote desktop, quality is really really choppy. So I tried switching to VNC. In VNC, the quality is fine, but the video plays very sluggish.  Now I tried using  on my iPad and accessed shared videos on my PC, and when I am streaming videos through infuse, they play fine, so I know that my LAN speed is good enough to support a decent video playback. So why don't the videos play well when I am using RDP or VNC, and is there any solution?


I was looking at the questions list in my profile page and I wonder why it says it has been modified by user Matthias, but opening the question I see no reference to that user:    This is a screenshot of my profile page:   Is it because the user posted an answer that has been deleted/not accepted or he modified the question and deleted/cancelled his editing?  Generally, what username and what date is put on the right side of each question?  Sorry if it's a duplicated question, I couldn't find an answer.

.       The  has no sign of the user sharth The  also does not have any sign of related activity   I would like to know why the user's name is associated with the question. At least why their display name shows up as having modified the question timeline activity.  Possible reason that I can think of is that, .  Is this the reason?  Is there a way (for normal users), to look for such details, other than looking at the user activity and the question's revision history.


I have a list with empty dictionaries. If I update one element of the list, I see same changes in all other elements as well. my_list = [{}] * 5 print(my_list) my_list[0]["name"] = "john" print(my_list)  Outputs: [{}, {}, {}, {}, {}] [{'name': 'john'}, {'name': 'john'}, {'name': 'john'}, {'name': 'john'}, {'name': 'john'}]  I expected an output like this: [{}, {}, {}, {}, {}] [{'name': 'john'}, {}, {}, {}, {}]  Any suggestions will be appreciated.

I needed to create a list of lists in Python, so I typed the following: my_list = [[1] * 4] * 3  The list looked like this: [[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]    Then I changed one of the innermost values: my_list[0][0] = 5  Now my list looks like this: [[5, 1, 1, 1], [5, 1, 1, 1], [5, 1, 1, 1]]    which is not what I wanted or expected. Can someone please explain what's going on, and how to get around it?


I'm having a rather strange problem with pgf-pie: it seems not to work very well when using the babel package...  See for yourself:  Without babel    With babel    Here is the code:  \documentclass[a4paper,11pt,final]{scrreprt} \usepackage{pgf-pie} \usepackage[french]{babel}  \begin{document}  \centering  \begin{tikzpicture} \pie{10/A, 20/B, 30/C, 40/D} \end{tikzpicture} % \hspace{1cm} % \begin{tikzpicture} \pie[polar]{10/A, 20/B, 30/C, 40/D} \end{tikzpicture}  \vspace{2cm}  \begin{tikzpicture} \pie[square]{40/A, 30/B, 20/C, 10/D} \end{tikzpicture} % \hspace{1cm} % \begin{tikzpicture} \pie[cloud, text=inside, scale font]{10/A, 20/B, 30/C, 40/D} \end{tikzpicture}  \end{document}   Has anyone seen this before? How to fix it?  Thanks in advance.

I would like to declare functions in tikz for multiple uses of the same function within the code.  Sadly, it seems that the tikz "declare function" is not compatible with the french option in babel. Indeed, the following code (that I simplifed on purpose) runs fine :  \documentclass[english]{article} \usepackage{babel}                       \usepackage{tikz}  \begin{document} \begin{tikzpicture}     \tikzset{declare function={Carre(\t)=\t*\t;}}     \draw plot [domain=-1:1] (\x,{Carre(\x)}); \end{tikzpicture} \end{document}   But when I replace   \documentclass[english]{article}   with   \documentclass[english,french]{article}   compilation generates an error. This is what the log file says :     Missing character: There is no = in font nullfont!   Missing character: There is no @ in font nullfont!   Missing character: There is no @ in font nullfont!      Runaway argument?   -1:1] (\x ,{Carre(\x )}); \end {tikzpicture} \end {document}    ! Paragraph ended before \pgfmath@local@@functions was complete.                          \par    l.18       I suspect you've forgotten a `}', causing me to apply this   control sequence to too much text. How can we recover?   My plan is to forget the whole thing and hope for the best.   Before posting this, I updated all packages without success.  Any help welcome!


I have a pdf catalog that was given to me from a client in pdf format. They don't have the images but they're in the pdf. Is there a way to extract all images from a pdf using a command line tool while preserving it's original file names? I reviewed this question here:   but it's for individual images.

Before I started using Ubuntu I used Nitro PDF reader to automatically extract images from PDF files. Is there a PDF reader for Linux that does this?  I would like to be able to extract images faster/easier than when taking a snapshot.


This is what happened:  ubuntu@ubuntu:~$ ubuntu-device-flash touch --channel=ubuntu-touch/stable/ubuntu  Get https://system-image.ubuntu.com/channels.json: dial tcp: lookup system-image.ubuntu.com on 127.0.1.1:53: no such host"   I had to write Ubuntu 16.04 to a flash drive an boot off of it because this package is not available for Ubuntu 18.04.

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


Should I repeat the by enumeration different theatres?  He has worked with many Moscow theatres, among them there are the Russian Academic Youth, the Maly, the Yermolova, the Oleg Tabakov, the Russian Army, the Pushkin and the Mossoviet theatres and the Moscow Operetta.   By the way, should I also repeat the word theatres in the end as I do in the example?

I am a bit confused about the rule of setting the definite article in a sentence when it is associated to two nouns.          The beginning and end of the channel.    The beginning and the end of the channel.           The arguments belong to the request and to data function.    The arguments belong to the request and to the data function.


The infamous Bard Venti has a catchphrase: "Wouldn't gliding be faster?" I think this is only the case when you have those white booster rings. These are, however, not commonly around when traversing the overworld. But what is the fastest way to move around the overworld in Genshin impact that you can achieve without taking advantage of these booster rings that I can utilise wherever I go on the overworld? I'm looking for a consistent method that I can apply in every region and every situation, so I'm not looking for , but the most consistent method or combination of methods of movement that I can apply regardless of team combination. Ideally, an answer would contain an order of operations such as always teleport to the nearest waypoint, always select your tallest character etc.

So from what I can tell there are no mounts, and my only means of movement are either teleporting to waypoints and temples, or sprinting and gliding everywhere.  Since I'm aware that this has a China version, but I've never really played the Chinese version, are there mounts or accessories of any sort that make moving faster? I do know that upgrading the Shrines of the Seven increase my stamina, but that doesn't necessarily seem to make my character move any faster while gliding or sprinting, it just gives a longer duration. Are there are any sets that perhaps make movement faster? Or any food items that make me move faster?


I'm curious how people measure quantitatively photosynthetic rate in labs.  I've seen many qualitative examples with direct observations of bubbles forming in water due to photosynthetic output of aquatic plants.  The ways I have come up with are:   to measure the CO2 intake. to measure the O2 output. to measure the amount of sugar produced.   The 3rd option seems most trivial, but I don't know how to measure the amount of CO2 present in a container. With a reaction? Or with a measuring machine of some sort? What about O2?

How is photosynthesis observed?    Say I have plants A and B, and I want to find how fast they are able to turn carbon dioxide into oxygen. How would I experiment this? Say I have one plant A, which has two kinds of leafs B and C. I hypothesize the B-leafs produce oxygen faster than the C-leafs. What kind of experiment could I set up to test this?


$X,Y$ are random independent variables with normal distribution. Can we conclude that $XY$ has also normal distribution ?     I know definition of normal distributio, however I have a problem with it. Can you explain it ?

Say I have $X \sim \mathcal N(a, b)$ and $Y\sim \mathcal N(c, d)$.  Is $XY$ also normally distributed?  Is the answer any different if we know that $X$ and $Y$ are independent?


What is the definition of convergence? The reason why I'm asking this question is to understand why $\frac1x$ diverges and $\frac1{x^2}$ converges.  The $\lim_{x\to\infty}\frac1x=0$ as does $\lim_{x\to\infty}\frac1{x^2}$. So why is one convergent and one divergent?

I am struggling understanding intuitively why the harmonic series diverges but the p-harmonic series converges. I know there are methods and applications to prove convergence, but I am only having trouble understanding intuitively why it is. I know I must never trust my intuition, but this is hard for me to grasp. In both cases, the terms of the series are getting smaller, hence are approaching zero, but they both result in different answers. $$\sum_{n=1}^{\infty}\frac{1}{n}=1+\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+\cdots = \text{diverges}$$   $$\displaystyle \sum_{n=1}^{\infty}\frac{1}{n^2}=1+\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+\cdots =\text{converges}$$


I receive scenario data (identical sets of variables with different values by scenario) in the form of python modules.  Example:  scen00.py:  scenario_name = ["foo"] scenario_num = [0] . .   scen01.py:  scenario_name = ["bar"] scenario_num = [1] . .   I import each scenario to a separate incidence of a python function using import as, and then do all of the programming, referencing the base namespace.  Example:  import sys  def main():      script = sys.argv[0]     no_scens = int(sys.argv[1])      for i in range(0, no_scens):         process_1(i)  def process_1(scen_count):      if scen_count == 0:         import scen00     elif scen_count == 1:         import scen01 as scen00      print(scen00.scenario_name[0], scen00.scenario_num[0])   Expected Outcome:  foo 0 bar 1   While this code works when no_scens is 2, the segment in process_1() which assigns the different scenarios to scen00 is not scalable and inelegant. Assuming I now have 150 scenarios to import, how could I best modify process_1()?

I'm writing a Python application that takes as a command as an argument, for example:  $ python myapp.py command1   I want the application to be extensible, that is, to be able to add new modules that implement new commands without having to change the main application source. The tree looks something like:  myapp/     __init__.py     commands/         __init__.py         command1.py         command2.py     foo.py     bar.py   So I want the application to find the available command modules at runtime and execute the appropriate one.  Python defines an __import__ function, which takes a string for a module name:     __import__(name, globals=None, locals=None, fromlist=(), level=0)      The function imports the module name, potentially using the given globals and locals to determine how to interpret the name in a package context. The fromlist gives the names of objects or submodules that should be imported from the module given by name.       Source:    So currently I have something like:  command = sys.argv[1] try:     command_module = __import__("myapp.commands.%s" % command, fromlist=["myapp.commands"]) except ImportError:     # Display error message  command_module.run()   This works just fine, I'm just wondering if there is possibly a more idiomatic way to accomplish what we are doing with this code.  Note that I specifically don't want to get in to using eggs or extension points. This is not an open-source project and I don't expect there to be "plugins". The point is to simplify the main application code and remove the need to modify it each time a new command module is added.


I was doing some queries on the Data Explorer and I noticed that the post Body is stored in HTML format instead of Markdown like I expected.  I'm interested in parsing this HTML () to convert to a different markup language.    For this parsing, it would help to know if a particular subset of HTML tags are used.  (i.e. <b> is never used, or something similar)  Is there a listing of such tags?

Stack Exchange sites use  for questions and answers. Per the Markdown specification, intermixing HTML and Markdown tags is allowed, but not all the HTML tags are allowed, to avoid . Which HTML tags are allowed on Stack Exchange sites?


For example, when my code is as shown below, I get -1301113336 for a = 0 and -1266657529 for a = 1 to 99.  #include <stdio.h>  int main() {     int a;     for (a = 0; a < 100; a++)     {         printf("\n%i");     } }   Is this some kind of undefined case when behaviour varies by compiler? If I use gcc, where do these numbers come from and why does it not change for each iteration?

I've just encountered a weird problem, I'm trying to printf an integer variable, but I forgot to specify the variable name, i.e.  printf("%d");   instead of  printf("%d", integerName);   Surprisingly the program compiles, there is output and it is not random. In fact, it happens to be the very integer I wanted to print in the first place, which happens to be m-1.  The errorneous printf statement will consistently output m-1 for as long as the program keeps running... In other words, it's behaving exactly as if the statement reads  printf("%d", m-1);   Anybody knows the reason behind this behaviour? I'm using g++ without any command line options.  #include <iostream> #define maxN 100 #define ON 1 #define OFF 0  using namespace std;  void clearArray(int* array, int n); int fillArray(int* array, int m, int n);  int main() {     int n = -1, i, m;     int array[maxN];     int found;      scanf("%d", &n);      while(n!=0)     {         found=0;         m = 1;         while(found!=1)         {             if(m != 2 && m != 3 && m != 4 && m != 6 && m != 12)             {                 clearArray(array, n);                 if(fillArray(array, m, n) == 0)                 {                     found = 1;                 }             }             m++;         }          printf("%d\n");          scanf("%d", &n);     }      return 0; }  void clearArray(int* array, int n) {     for(int i = 1; i <= n; i++)         array[i] = ON; }  int fillArray(int* array, int m, int n) {     int i = 1, j, offCounter = 0, incrementCounter;      while(offCounter != n)     {         if(*(array+i)==ON)          {             *(array+i) = OFF;             offCounter++;                }         else          {             j = 0;             while((*array+i+j)==OFF)             {                 j++;             }             *(array+i+j) = OFF;             offCounter++;                    }         if(*(array+13) == OFF && offCounter != n) return 1;         if(offCounter ==n) break;          incrementCounter = 0;                while(incrementCounter != m)         {             i++;             if(i > n) i = 1;             if(*(array+i) == ON) incrementCounter++;          }            }      return 0; }


I have an array and i want to create an independent copy of it. Changes in one of those should not impact the other at all.   Currently everything i tried just created two references on one object. The default clone() method did not work aswell.  JButton[][] old = game.getFields().clone(); // getFields() returns a two dimensional array

It's a bit difficult to implement a deep object copy function. What steps you take to ensure the original object and the cloned one share no reference?


is ist possible to find the Fourier transform (direct and inverse ) of  $ f(x)= \frac{1}{|x|^{k}} $ for $ k=1,2,3,......$  this function has a severe singularity at  $x=0$ so i think this will exists only in the sense of distributions :)

I'd like to find the $n$-dimensional inverse Fourier transform of $\frac{1}{\| \mathbf{\omega} \|^{2\alpha}}$ i.e. $$ \int_{\mathbb{R}^n} \frac{1}{ \| \mathbf{\omega} \|^{2\alpha}} e^{2 \pi i \mathbf{\omega}\cdot \mathbf{x} } d \mathbf{\omega} $$ where $\mathbf{x} = ( x_0 , x_1 , \cdots , x_n )$ is a spatial parameter in $\mathbb{R}^n$, $\mathbf{\omega} = ( \omega_0 , \omega_1 , \cdots , \omega_n )$, and $$ \| \omega\| = \omega_0^2 + \omega_1^2 + \cdots + \omega_n^2 $$ All I've been able to come up with in the one-dimensional case is that the integral $$ \int_{-\infty}^{+\infty} \frac{1}{ \| \omega \|^{2\alpha}} e^{2 \pi i \omega x } d \mathbf{\omega} $$ diverges because the lower power terms $\omega^p$ terms, for which $p < 2\alpha$, in expansion of the exponential $$ e^{2 \pi i \omega x } = \sum_{p = 0}^{\infty} \frac{(2 \pi i \omega x)^p}{p!} $$ do not prevent $\frac{1}{\| \omega \|^{2\alpha}}$ from blowing up at the origin.   I know that one possible way of regularizing this integral is to include a test function and consider the limit of the resulting integral, but I don't quite know how to do so. I've tried reading Gelfand and Shilov's Gneralized Functions vol 1 and while I understand bits of it on the whole its a bit heavy for me.    Based on the papers that I've read I know that there are two cases (the latter of which appears to me more general) and two solutions in each.   Case 1: 2$\alpha$ is an odd/even integer Case 2: 2$\alpha$ is integer or otherwise   I'd appreciate help, if possible, coming up with both solutions.


My tag scores according to my profile have not been updated on the site for the last few days.  I thought that it was due to something similar to this question:    However, when checking out my profile in the Android App, the scores are being updated.

From my , I learned that all tag related info on profile will be updated daily at UTC 03:00.  However, something is wrong here. It's now UTC 05:00+, but my tag number, say 93 (c++) is not updated against yesterday. I am pretty sure about this and I did earn some more points throughout the day. Sorry for not be able to capture the screenshot yesterday, but I did check this number 10 hours ago (which belongs to yesterday, also 93).  Is there a bug happening here? Or updating time different?    UPDATE: As of 24 Jan, the tags are still not updated with the proper values.  UPDATE2: Fixed around 25 Jan, UTC 03:00, at least for me.


This is obviously the sort of problem that fascinates a kid, as it did me when I was younger. I became reminded of it when looking for creative ways to bound the sum below from :  $\displaystyle \sum_{n=1}^{\infty}\frac{1!+...+n!}{(n+2)!}$  So, is there a closed form for $A=\displaystyle \sum_{n=0}^{\infty}\frac{1}{n^n}=\frac{1}{1}+\frac{1}{2^2}+\frac{1}{3^3}+...?$  If you're wondering, $A$ is a poor upper bound for each term in the sum.

Earlier today, I was talking with my friend about some "cool" infinite series and the value they converge to like the Basel problem, Madhava-Leibniz formula for $\pi/4, \log 2$ and similar alternating series etc.  One series that popped into our discussion was $\sum\limits_{n=1}^{\infty} \frac{1}{n^n}$.  Proving the convergence of this series is trivial but finding the value to which converges has defied me so far. Mathematica says this series converges to $\approx 1.29129$.  I tried Googling about this series and found very little information about this series (which is actually surprising since the series looks cool enough to arise in some context).  We were joking that it should have something to do with $\pi,e,\phi,\gamma$ or at the least it must be a transcendental number :-).  My questions are:   What does this series converge to? Does this series arise in any context and are there interesting trivia to be known about this series?   I am actually slightly puzzled that I have not been able to find much about this series on the Internet. (At least my Google search did not yield any interesting results).


What is the best book to learn probability - Poisson, binomial, regression, etc.  I am working as an odds adjuster at a bookmaker and need to advance my skills to an odds compiler level.

I'm studying machine learning and every book I open I bump into chi-squared distribution, gamma-function, t-distribution, Gaussian, etc.   Every book I have opened so far only defines what the distributions are: they don't explain or give the intuition on where the specific formulas for the functions come from.   For example, why is chi-squared distribution the way it is? What is the t-distribution? What is the intuition behind the distribution? Proofs? etc.   I would like to have a clear and fundamental understanding of the most commonly used distributions so that every time later on when I see them, I truly understand what is a t-distribution, what is a Gaussian distribution and most importantly why are they the way they are.   It would be nice if the books / tutorials  can explain the concepts to a layman so that in order to understand them you don't already need to understand them x) Many books are like this, they don't fit for beginners :(


I have this private class attribiute and I want to change its value in prototyped method. But "privateVariable" is not visible in "increment" method. How can I access this attribute from this method?  var myClass = function(){     var privateVariable = 1 }  myClass.prototype.increment=function(){     privateVariable++ }   Mind you that it is a private attribute.

Is there any way to make “private” variables (those defined in the constructor), available to prototype-defined methods?  TestClass = function(){     var privateField = "hello";     this.nonProtoHello = function(){alert(privateField)}; }; TestClass.prototype.prototypeHello = function(){alert(privateField)};   This works:  t.nonProtoHello()   But this doesn’t:  t.prototypeHello()   I’m used to defining my methods inside the constructor, but am moving away from that for a couple reasons.


I'm given the position vector:  $$    r(t) = ht \hat\imath + t(v − 5mt) \hat\jmath$$  where $m$ = mass, $h$ = horizontal speed and $v$ = vertical speed.  Then the following data is given:  $$\begin{array}{lcc}     \mbox{dist.} & 72 & 120 & 192 & 288 \\     \mbox{height} & 68.4 & 110 & 166.4 & 230.4 \\     \mbox{time} & t_1 & t_2 & t_3 & t_4 \end{array}$$  The question is, Using the position vector, find a range for the missile in terms of $m,$ $v$ and $h.$  How would i go about doing this? Totally stumped as i've just started learning vectors. My only initial thought is to incorporate $vh/5m.$ Any help would be greatly appreciated!

a missile has the position vector P(t) = ht i + t(v − 5mt) j.  where m is the mass (kg) of the missile, and h/v is the horizontal/vertical speed (respectively) the missile is launched with.  Using the position vector, find a range for the missile in terms of m, v and h.  looked at several links, (,  (page 43)) both show different ways of showing the range but none include mass.  I tried working with SUVAT equations but again, no mass.  I've run out of ideas.


I get this line repeatedly:  W: Possible missing firmware /lib/firmware/i915/kbl_dmc_ver1_01.bin for module i915   This is the whole process (German):   What is this about?

When I run a kernel or NVIDIA driver update on my 16.04, this triggers an initramfs rebuild which outputs the warning below:  Processing triggers for initramfs-tools (0.122ubuntu8.1) ... update-initramfs: Generating /boot/initrd.img-4.4.0-34-generic W: Possible missing firmware /lib/firmware/i915/skl_guc_ver6.bin for module i915_bpo   I have a notebook with two graphics chips, an NVIDIA GeForce 940M and the Intel i5-6200U's integrated graphics.  The device in use is my NVIDIA card:  $ inxi -G Graphics:  Card-1: Intel Sky Lake Integrated Graphics            Card-2: NVIDIA GM108M [GeForce 940M]            Display Server: X.Org 1.18.3 driver: nvidia Resolution: 1920x1080@60.03hz            GLX Renderer: GeForce 940M/PCIe/SSE2 GLX Version: 4.5.0 NVIDIA 367.35   Here's the output of lshw -c video, corresponding to my Intel graphics chip which should use that driver:      *-display                   description: VGA compatible controller          product: Sky Lake Integrated Graphics          vendor: Intel Corporation          physical id: 2          bus info: pci@0000:00:02.0          version: 07          width: 64 bits          clock: 33MHz          capabilities: pciexpress msi pm vga_controller bus_master cap_list rom          configuration: driver=i915_bpo latency=0          resources: irq:125 memory:a2000000-a2ffffff memory:b0000000-bfffffff ioport:5000(size=64)   The file in the warning does not exist, only those:  $ ll /lib/firmware/i915/ total 336 drwxr-xr-x  2 root root   4096 Aug 11 13:24 ./ drwxr-xr-x 74 root root  32768 Aug 11 13:24 ../ -rw-r--r--  1 root root   5872 Jul 21 17:03 bxt_dmc_ver1_04.bin -rw-r--r--  1 root root   5872 Jul 21 17:03 bxt_dmc_ver1_05.bin -rw-r--r--  1 root root   8380 Jul 21 17:03 bxt_dmc_ver1_06.bin -rw-r--r--  1 root root   8380 Jul 21 17:05 bxt_dmc_ver1_07.bin lrwxrwxrwx  1 root root     19 Jul 21 17:05 bxt_dmc_ver1.bin -> bxt_dmc_ver1_07.bin -rw-r--r--  1 root root   8824 Jul 21 17:03 skl_dmc_ver1_23.bin -rw-r--r--  1 root root   8928 Jul 12 21:33 skl_dmc_ver1_26.bin lrwxrwxrwx  1 root root     19 Jul 12 21:33 skl_dmc_ver1.bin -> skl_dmc_ver1_26.bin -rw-r--r--  1 root root 109636 Jul 21 17:03 skl_guc_ver1_1059.bin lrwxrwxrwx  1 root root     21 Jul 21 17:03 skl_guc_ver1.bin -> skl_guc_ver1_1059.bin -rw-r--r--  1 root root 128320 Jul 21 17:03 skl_guc_ver4_3.bin lrwxrwxrwx  1 root root     18 Jul 21 17:03 skl_guc_ver4.bin -> skl_guc_ver4_3.bin   The latest driver package seems to be installed though:  $ apt-cache policy xserver-xorg-video-intel xserver-xorg-video-intel:   Installed: 2:2.99.917+git20160325-1ubuntu1   Candidate: 2:2.99.917+git20160325-1ubuntu1   Version table:  *** 2:2.99.917+git20160325-1ubuntu1 500         500 http://ftp.uni-stuttgart.de/ubuntu xenial/main amd64 Packages         100 /var/lib/dpkg/status   What does this warning mean exactly and how can I fix it?


So, While building a simpel neural net (MLP) for recognizing digits, I ordered my function to print me both the mean cost overall off the train dataset and %currect answers, also over the train dataset (even though the function doing this is called val()). the cost kept going down for an hour and a half, but the %currect answers stayed the same as the beginning.  the wierd thing is that while the cosr is constantly going down, the train accurasy do not change AT ALL from the very beggining.   Any ideas why this is happening?   Here is the , if needed.

I am looking at learning curves (, which is based on ) and trying to play with regularization to prevent overfitting. This model uses L2 regularization and dropout.  What is interesting is that by looking at the accuracy graph I cannot really tell which model is the best. On the other hand the loss graph shows some differences. See pictures below.  Here are my question:    should we always look at the loss curves to check for overfitting? the accuracy graph is not very precise because accuracy is discrete and a lot of information gets lost when we compute it?


I just moved from Windows 7 to 10.  The Windows 7 start menu would show me recent documents.  I found this convenient.  It looked like this:    Now in Windows 10, I don't see a "Recent" list lie in Windows 7.  Instead I see this ugliness.  Is there a way to get some sort of recent list when I hover over an application icon?

I can find recent items settings, but these seem to only let me see recent items opened on a per-app basis i.e. I can look at my Microsoft Word icon and see recent documents opened by Word.  I can't see anywhere a simple "these are the last 10 documents/files you opened with any application" which is handy if I don't pin the apps in question to my startbar. This used to exist under Windows XP as "My Recent Documents":    Is there a way to get this functionality?  For example: I open doc.docx, sheet.xlsl, options.txt, picture.bmp with different tools and then see these items listed in one place indicating the files I most recently opened?


I can't say I get it. I think the difference is:   'The Germany National team' is team which represents Germany as a country. And it is its formal title.  'the German national team' is team which represents Germany as a country. But in this case it is emphasised that this one is German, i.e. "This is the German national team and that one is the French"    Am I right?

Why is the team from Germany called "Germany National Team", not "German National Team"? On official Internet sites, it is the same for every official national team; Germany National, France National, Poland National, Russia National etc. etc. What truthfully bothers me is why not German, French, Polish, Russian etc?


Let's imagine that we have two positive integers $k_1$ and $k_2$ so that $k = k_1 + k_2$. Can we assume that for any pair of $k_1$, $k_2$: $$ k_1! k_2! \leq k! \quad \text{?} $$ Intuitively, I would say yes, but I'm looking for a proof.

Prove that for positive integers $a_1,\dots,a_k$ (where $k\geq 1)$  are such that $a_1+\cdots+a_k < n$ , then $a_1!\cdots a_k! < n!$.   So far, i've tried adding the condition that suppose they were also in increasing order. I've thought about using induction to prove it, but it seems like this is not the right approach to go about this. Without induction, I am struggling to somehow use the fact that:  $$a_1+\cdots+a_k < n \implies (a_1+\cdots+a_k)! < n! $$ and relate $\displaystyle \left(\sum a_i\right)!$ to $\displaystyle \prod a_i!$.  How does one proceed?


I am a South Korean national, and currently hold a Aufenthaltstitle in Germany as a job seeker, which is expiring as of Dec. 24. I had previously worked in Germany for almost 3 years, then my employment ended on June 30 and I was able to extend my stay as a job seeker until Dec.24.  I have recently traveled to the US, and on my way back I got my passport stamped in Lisbon on Nov.15, and I am curious to know whether this allows me to stay in Germany longer (up to 90 days from Nov.15) than my Aufenthaltstitles' expiration date.     To add a bit...  My question is whether the entry stamp in Lisbon on Nov. 15 would still be valid, even if my residence is not expired at that point yet. Or do I need to exit the country and get another stamp after the Aufenthaltstitel is expired. Any clarification will be very much appreciated.

I have a 1-year residence permit from one Schengen country that is now expiring. Upon its expiration, I would like to get my 90/180 days validity as a tourist to stay, or return here as soon as possible.  I understand that the tourist short-stay scheme is based on the 90/180 days "counter". But what happens if my previous stay was not tourism but residence (as searching year). Wouldn't that mean that I can quickly exit and re-enter the Schengen area to activate my tourist stay?   Also, is there a way to change this purpose of stay without exiting the Schengen area?


This is the solution that my book gives ($\mathbb{F}_p$ is the finite field with $p$ elements):  We can assume that $p\neq 2,3$ because $0$ is a root of $f(x)$ in $\mathbb{F}_2$ and $\mathbb{F}_3$. Let $Q$ be the "squares subgroup" (?) of index $2$ in $\mathbb{F}_p^*$. If $2$ and $3$ are not in $Q$ (this means that $(x^2-2)(x^2-3)$ doesn't have roots in $\mathbb{F}_p$), then $2 \cdot 3 \in Q$ (?), and then $x^2-6$ has a root in $\mathbb{F}_p$.  Honestly, I don't understand this solution at all: what is the "squares subgroup" of $\mathbb{F}_p^*$? And why $2 \cdot 3$ must be in this group?

Suppose the $p$ is an odd prime not dividing $ab$.  Prove that $z^2 \equiv ab \pmod p$ is solvable if and only if both or neither of $x^2\equiv a\pmod{p}$ and $x^2 \equiv b \pmod p$ are solvable.


I wonder if it is possible to draw the following figures in latex:    For the first image I want a typical real analysis diagram. For the other three I want to draw a cylinder and with squares and rhombus sections...  Is this possible with latex?  Ŕeferences  For my own reference I save here some examples of tikz referenced in the comments:

I'm trying to draw a cylinder on the three dimensional space, and I also want its projection on the x--y plane. I found the first answer  to be very useful. I just copy-paste it to my document, and modify it as follows (the modifications are only inside the \begin{tikzpicture} tags):   \documentclass[parskip]{scrartcl} \usepackage[margin=15mm]{geometry} \usepackage{tikz}  \pgfmathsetmacro{\xdeg}{30} \pgfmathsetmacro{\xx}{cos(\xdeg)} \pgfmathsetmacro{\xy}{sin(\xdeg)}  \pgfmathsetmacro{\ydeg}{120} \pgfmathsetmacro{\yx}{cos(\ydeg)} \pgfmathsetmacro{\yy}{sin(\ydeg)}  \pgfmathsetmacro{\zdeg}{80} \pgfmathsetmacro{\zx}{cos(\zdeg)} \pgfmathsetmacro{\zy}{sin(\zdeg)}  \newcommand{\tdcyl}[5]{% origin x, origin y, origin z, radius, height     \path (1,0,0);     \pgfgetlastxy{\cylxx}{\cylxy}     \path (0,1,0);     \pgfgetlastxy{\cylyx}{\cylyy}     \path (0,0,1);     \pgfgetlastxy{\cylzx}{\cylzy}     \pgfmathsetmacro{\cylt}{(\cylzy * \cylyx - \cylzx * \cylyy)/ (\cylzy * \cylxx - \cylzx * \cylxy)}     \pgfmathsetmacro{\ang}{atan(\cylt)}     \pgfmathsetmacro{\ct}{1/sqrt(1 + (\cylt)^2)}     \pgfmathsetmacro{\st}{\cylt * \ct}     \filldraw[fill=white] (#4*\ct+#1,#4*\st+#2,#3) -- ++(0,0,#5) arc[start angle=\ang,delta angle=-180,radius=#4] -- ++(0,0,-#5) arc[start angle=\ang+180,delta angle=180,radius=#4];     \filldraw[fill=white] (#1,#2,#3+#5) circle[radius=#4]; }       \begin{tikzpicture}[x={(\xx*1cm,\xy*1cm)},y={(\yx*1cm,\yy*1cm)},z={(\zx*1cm,\zy*1cm)}]          \tdcyl{-3}{-3}{0}{1}{3} % x y z   r h         \tdcyl{0}{0}{0}{1}{3} % x y z   r h           \draw (-3,0,0) -- (3,0,0) node[circle,fill=white] {x};         \draw (0,-3,0) -- (0,3,0) node[circle] {y};         \draw (0,0,-3) -- (0,0,3) node[circle] {z};     \end{tikzpicture}     \end{document}   I added another cylinder and tweaked the positions to fit what I need. This produces the following:      Which is almost what I want, except that I want to see the projection of that cylinder on the x--y plane, but unfortunately, the top cylinder hides the full circle. When I disable the top cylinder:      \begin{tikzpicture}[x={(\xx*1cm,\xy*1cm)},y={(\yx*1cm,\yy*1cm)},z={(\zx*1cm,\zy*1cm)}]          \tdcyl{-3}{-3}{0}{1}{3} % x y z   r h            \draw (-3,0,0) -- (3,0,0) node[circle,fill=white] {x};         \draw (0,-3,0) -- (0,3,0) node[circle] {y};         \draw (0,0,-3) -- (0,0,3) node[circle] {z};     \end{tikzpicture}   Now the projection is shown again:   But the top cylinder is missing...  How can I make the top cylinder transparent, or, alternatively, and even better; how do I create one long cylinder and emphasize its projection on the x--y plane?   BTW, what determines the position of the labels x,y,z in the above code? I want to reposition them so they won't overlap with the axis. Thanks in advanced!


I want to invite various people to a shared Google Drive folder but do not want each of the users (except myself) to see the names of the other users with which the folder has been shared.

For Google sheets sharing setting, I have it on "Specific people can access", but the people can see who has access to that sheet. Is there anyway to make the setting so that the specific people can't see who else has access to that sheet?


I would like to evaluate the sum of the following geometric progression  $1 -2 + 2^{2} - 2^{3} + ...+(-1)^{n}2^{n}$  Would the following proposed solution be on the right lines?  $a = 1$ (Being the first term)  $r = -2$ (Being the common ratio)  $n = n + 1$ (The number of terms we want to consider in this case)  The formula to evaluate the sum of a geometric progression being:  $$\frac{1 - r^n}{1 - r}.$$  Therefore, plugging in the values above  $$\frac{1 - (-2)^{n+1}}{3}.$$  Thanks

Why does the following hold:  \begin{equation*} \displaystyle \sum\limits_{n=0}^{\infty} 0.7^n=\frac{1}{1-0.7} = 10/3\quad ? \end{equation*}  Can we generalize the above to      $\displaystyle \sum_{n=0}^{\infty} x^n = \frac{1}{1-x}$ ?   Are there some values of $x$ for which the above formula is invalid?  What about if we take only a finite number of terms? Is there a simpler formula?     $\displaystyle \sum_{n=0}^{N} x^n$   Is there a name for such a sequence?    This is being repurposed in an effort to cut down on duplicates, see here: Coping with  duplicate questions.  and here: .


I purchased this laptop a year or so ago and immediately switched to Ubuntu since it was faster and did everything that I needed it for faster.   Except now I would like to dual boot, but can't figure how to hell to run a program to install Windows 8 on a different partition. I don't have the code itself (it's tied to the motherboard), and MS has removed the option for a bootable Win 8 disk. Every other executable I've found (even trying to get Win7 through less than proper means) doesn't work on Ubuntu.

I have Ubuntu on my laptop. Now I want install Windows 7 in a dual-boot. How can I do this? I can't lose my Ubuntu files, and I'm afraid that I might break . Go  for UEFI only!


The hard drive in my MacBook has only 128Gb of space. I therefore wanted to install Windows on an USB drive. The Windows installer doesn't allow me to select the USB drive however. Questioning the internet it seems to simply be that way. There was some Media Creation Tool mentioned somewhere to create a Windows USB drive, but that requires Windows to use.  Is my only hope therefore to find a Windows Computer to create my Windows USB drive? Or is there some way to install Windows on an USB drive with my MacBook?

I want to install Windows 7 on an external hard drive, and boot from it when needed.   Is this possible on a Mac? I have heard from some sources that it is not possible to boot Windows from external drives, at least on the new Macs. I found this quite surprising.   Any idea if this is true?


In my application multiple processes are trying access a file for read and write. Every application has a single thread. I need to make sure that no 2 processes are accessing the file at the same time. I am using FileLock in JDK. This works fine, when one process has acquired the lock and other process tries to access to the file (for read or write) exception is thrown stating file has been locked by other process.  Now i need to make sure that, for 2nd process rather then throwing the exception thread should wait till lock is released by first process and once lock is released continue with its work.  How can I do this. So, fat I have not been able it figure out someway of doing this.

I have a Java process that opens a file using a FileReader. How can I prevent another (Java) process from opening this file, or at least notify that second process that the file is already opened? Does this automatically make the second process get an exception if the file is open (which solves my problem) or do I have to explicitly open it in the first process with some sort of flag or argument? To clarify: I have a Java app that lists a folder and opens each file in the listing for processing it. It processes each file after the other. The processing of each file consists of reading it and doing some calculations based on the contents and it takes about 2 minutes. I also have another Java app that does the same thing but instead writes on the file. What I want is to be able to run these apps at the same time so the scenario goes like this. ReadApp lists the folder and finds files A, B, C. It opens file A and starts the reading. WriteApp lists the folder and finds files A, B, C. It opens file A, sees that is is open (by an exception or whatever way) and goes to file B. ReadApp finishes file A and continues to B. It sees that it is open and continues to C. It is crucial that WriteApp doesn't write while ReadApp is reading the same file or vice versa. They are different processes.


I’m taking an online “Intro to AI” course for which I’m doing some azure machine learning labs.  This course is largely about how to apply azure ML solutions and, while there is an “essential math for ML module”, it doesn’t do any sort of deep dive into the math/statistics. But I want to understand what’s happening mathematically to a basic level. (I've taken an intro to statistics, that's it so far.)  Below are some details about some specific things I’d like to understand more, and my specific questions.  At a particular point in the “training a classification model” lab, there is this text: “The distribution of the Age column in the diabetes.csv dataset is skewed because most patients are in the youngest age bracket. Creating a version of this feature that uses a natural log transformation can help create a more linear relationship between Age and other features, and improve the ability to predict the Diabetic label. This kind of feature engineering as it’s called is common in machine learning data preparation.”  Then the instructions show you how to use Azure ML Studio to apply the natural log operation to the age column in the data set:   And after doing that, the data includes the original/raw age data and the transformed age data:   Question #1: What is that transformation actually doing? I don't mean the nitty gritty math, but what is it doing conceptually?    Question #2: The next general question is around why is a transformation necessary.  On that, I did some research and found this article () that describes which type of log transformations to use in a few scenarios.  Here’s a snip of text from the article: “The need for data transformation can depend on the modeling method that you plan to use. For linear and logistic regression, for example, you ideally want to make sure that the relationship between input variables and output variables is approximately linear, that the input variables are approximately normal in distribution, and that the output variable is constant variance (that is, the variance of the output variable is independent of the input variables). You may need to transform some of your input variables to better meet these assumptions.”  I don’t understand why any of that is necessary.  I’ve broken my question down:  For linear and logistic regression, for example, you ideally want to make sure that: the relationship between input variables and output variables is approximately linear – why? the input variables are approximately normal in distribution- why? the output variable is constant variance (that is, the variance of the output variable is independent of the input variables – why?  Could someone help with information for those whys, or point me to material that would help?

Am I looking for a better behaved distribution for the independent variable in question, or to reduce the effect of outliers, or something else?


This is a question/answer from my first assignment (intro class on pattern recognition)  I don't understand how they used the p(x given w1) and p(x given w2) in the discriminant function. For example, how did they used the mean vector [0,0] and [d, e] in g(x)?  Can someone explain the missing steps from the original function to the simplified one?  QUESTION:    ANSWER:

This is for my hw, and if anyone can solve the first part of the question it will be great. Here is the question:  Assume a two-class problem with equal a priori class probabilities and Gaussian class-conditional densities as follows:  $$p(x\mid w_1) = {\cal N}\left(\begin{bmatrix} 0 \\ 0 \end{bmatrix},\begin{bmatrix} a & c \\ c & b \end{bmatrix}\right)\quad\text{and}\quad p(x\mid w_2) =  {\cal N}\left(\begin{bmatrix} d \\ e \end{bmatrix},\begin{bmatrix} 1 & 0 \\ 0 & 1 \end{bmatrix}\right)$$  where $ab-c^2=1$.   Find the equation of the decision boundary between these two classes in terms of the given parameters, after choosing a logarithmic discriminant function. Determine the constraints on the values of a, b, c, d and e, such that the resulting discriminant function results with a linear decision boundary.


Hello guys, How to make numbers superscript? Just like in the picture below

What is the easiest way to superscript text outside of math mode?  For example, let's say I want to write the $n^{th}$ element, but without the math mode's automatic italicization of the th.  And what if I still want the n to be in math mode, but the th outside?


How can I apply this code to JavaScript?  This code will check email address validation in PHP. But i want to apply this code to JavaScript.  How can I do that?  PHP  <?php     $strEmail = $_POST[email_send_value];     if (!eregi("^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$", $strEmail))     {         // NOT OK //     }     else     {         // OK //     } ?>   JavaScript  <script>     var email_var = document.getElementById("CheckEmail").value;     .     .     .     .     . </script>

Is there a regular expression to validate an email address in JavaScript?


Could someone show me how to express this model mathematically?  I'm not sure I quite understand how to write it out because I feel like I'm seeing a lot of different notations in different books.

I would appreciate if someone could help me write the mathematical equation for the seasonal ARIMA (2,1,0) x (0,2,2) period 12. I'm a little confused with how to go about this. I would prefer an equation involving $Y_t , e_t, θ$ and $Θ$.


As I understand it, when I make a change in the tone curve in Adobe Photoshop (or Lightroom) and have selected the RGB Channel option, the following happens: For every pixel in the image, if any of the three color channels has the input value, it will be remapped to the output value. For example:  In following image, every pixel has RGB value 0,70,0    If we do the following change in the curve, we haven't change the point that corresponds to 0, but we have changed the point that corresponds to 70 and remapped it to 137. So in every pixel in the image, in red, green and blue channels, if the value is 70, it wll be remapped to 137.    When we have selected only one of the three channels, the change will be applied only to this channel.  Is my understanding of the tone curve correct or something else happens? Are the tones in a colored image actually the 256 values of RGB color system?

In simple terms, what does Tone Curve in LR actually do?. I can see the results of changing Tone Curve by playing around with it, but I don't really understand scientifically what it actually does. I read a few documents on it, including one from Adobe, but I just got lost.


I was playing around and wanted to consider the integral of $$I_n = \int_0^{\infty} \left(\frac{\sin x}{x}\right)^n \, \mathrm{d}x$$ using parts with $u = \sin^n x \implies \mathrm{d}u = n\cos x \sin^{n-1}x$ and $\mathrm{d}v = x^{-n} \implies v = \frac{x^{1-n}}{1-n}$  This gives $$I_n = \frac{n}{n-1}\int_0^{\infty} \left(\frac{\sin x}{x}\right)^{n-1} \cos x \, \mathrm{d}x$$  Which looks so close to $I_{n-1}$ but for that annoying $\cos x$ there, any help?  Note: I wanted to go down this route because I think I can note a pattern, as such:  $$I_1 = \frac{\pi}{2} \\ I_2 = \frac{\pi}{2} \\ I_3 = \frac{3\pi}{8} \\ I_4 = \frac{\pi}{3} \\ I_5 = \frac{115\pi}{384} \\ I_6 = \frac{11\pi}{40}$$

(Edit: Thank you Vladimir for providing the references for the closed form value of the integrals. My revised question is then to how to derive this closed form.)     For all $n\in\mathbb{N}^+$, define $\mathcal{I}_n$ by the definite integral,   $$\mathcal{I}_n:=\int_{0}^{\infty}\frac{\sin^n{(x)}}{x^n}\mathrm{d}x.$$   Prove that $\mathcal{I}_n$ has the following closed form:   $$\mathcal{I}_n\stackrel{?}=\pi\,2^{-n}\left(n\sum_{k=0}^{\lfloor\frac{n-1}{2}\rfloor}\frac{(-2)^k(n-2k)^{n-1}}{k!(n-k)!}\right),~~\forall n\in\mathbb{N}^+.$$     Integrals of small positive integer powers of the $\operatorname{sinc}$ function come up on a regular basis here, but it occurred to me that while I probably know the derivations for the $1\le n\le 4$ cases like the back of my hand, I can't recall ever working the integrals wfor any value of $n$ higher than that. The values of the first four integrals are,  $$\mathcal{I}_1=\frac{\pi}{2},\\ \mathcal{I}_2=\frac{\pi}{2},\\ \mathcal{I}_3=\frac{3\pi}{8},\\ \mathcal{I}_4=\frac{\pi}{3}.$$  So I set out to first calculate $\mathcal{I}_5$ to see if any obvious pattern jumped out (and see if the trend of being equal to rational multiples of $\pi$ continued). I wound up getting frustrated and asking WolframAlpha instead. It turns that while the first four cases hinted very much at the possibility of a simple pattern relating the values of $\mathcal{I}_n$ for different positive integers $n$ (or possibly two separate patterns for even and odd $n$), the next few values most definitely did not:  $$\mathcal{I}_5=\frac{115\pi}{384},\\ \mathcal{I}_6=\frac{11\pi}{40},\\ \mathcal{I}_7=\frac{5887\pi}{23040}\\ \mathcal{I}_8=\frac{151\pi}{630}.$$  So my questions are, 1) is there a systematic way to compute these integrals for all $n$?; and 2) is there an elegant way to represent these values in closed form for general $n$?


Okay, I know that the themes for normal user (with normal privileges) are stored in home/user/.themes...  But, I have also noticed that opening an application as root makes the app use a different (default) theme...  So, next I opened Gnome Tweaks as root, and tried to see what theme is being used, and found that the theme list is not the same as the one shown on Gnome Tweaks as a normal user, basically the externally added themes stored in .themes folder are missing.  So, I was thinking of making a separate theme for root access, but I couldn't find where to put my themes so that they get included in the root theme list. PRATAP helped me find them under user\share\themes...So, I added my theme there, and on running Gnome Tweaks as root the newly added theme was included in the list.  But, applying the new theme didn't change anything. So, is there a way to change the root user theme?    UPDATE-2 I have checked this:  But, this means that I'll have to use some extra attributes with sudo, I am wondering if there is a way to make this change permanent (as long as I don't change it again), so that all root apps use the theme by default.    My OS: Ubuntu 20.04

I use Kubuntu 19.10 and when I open GNOME apps like Nautilus or Gedit as root, they do not show in theme (Qogir-dark) that  I choose for GNOME apps, but in some strange black and white theme.   I tried to put Qogir folder to /.themes, but nothing (currently it is in /usr/share/themes). How can I correct that?


Is it problematic to use the ratio of two measurements as a response variables in linear regression?  Motivating Example: Modeling Differences  My motivation comes from the following understanding of differences of two measurements as response variables:   To understand how something changes over time using two measurements in series,  people often model as:  (T2i - T1i) = b0 + ei  And by rearrangement equivalent to:  T2i = b0 + 1.0 * T1i + ei  So, the relationship between T1 and T2 above is fixed at 1:1  Better would be:  T2i = b0 + b1 * T1i + ei  so that the relationship between T1 and T2 is estimated, not assumed. If indeed the relationship is not 1:1, this model will be better than the difference model.  My Question: What About Ratios?  Suppose we are analyzing the quantities of two parts that make a whole as a ratio, or a density in which we divide count data by effort data. So ...  (P1i / P2i) = b0 + ei  By rearrangement:   P1i = P2i * (b0 + ei)  If we distribute:   P1i = b0 * P2i + ei * P2i  What (on Earth) does this assume? Is it problematic? What if we have a linear predictor in the model? We end up with:  P1i = b0 * P2i + b1 * X1i * P2i + ei * P2i  Is it now true that b0 is an estimate of the relationship between P2 and P1 and that b1 is an estimate of the interactive effect of X1 and P1? Shouldn't be, because now there is no intercept, and no estimate for the effect of X1 is made. And what of the error term being multiplies by P2 -- that can't be good ... ?  A better model would appear to be:   P1i = b0 + b1 * P2i + b1 * X1i + ei  Now we are predicting P1 controlling for P2. Don't we get the same information here?   It is more clear that we do get the information we're looking for if thinking instead about density, where P1 is, say, the number of objects observed, and P2 is the effort spent sampling for them. To control for effort makes perfect sense, but is it equally valid to do division to create the response variable?

Recently, randomly browsing questions triggered a memory of on off-hand comment from one of my professors a few years back warning about the usage of ratios in regression models. So I started reading up on this, leading eventually to Kronmal 1993.  I want to make sure that I'm correctly interpreting his suggestions on how to model these.   For a model with a ratio with the same denominator on both the dependent and independent side: $ Z^{-1}Y = Z^{-1}1_n\beta_0 + Z^{-1}X\beta_X + \beta_Z + Z^{-1}\epsilon $   Regress dependent ratio on the (inverse) denominator variable in addition to the other ratios Weight by the (inverse) denominator variable  For a model with dependent variable as a ratio: $ Y = \beta_0 + \beta_XX + Z1_n\alpha_0 + ZX\alpha_X + Z^{-1}\epsilon $   Regress numerator by original variables, denominator, and denominator times original variables [what about categorical variables?] Weight by (inverse) denominator  For model with only independent variable ratios: $ Y = \beta_0 + X\beta_X + Z^{-1}1_n\beta_{Z^{-1}} + W\beta_W  + Z^{-1}W\beta_{Z^{-1}W} + \epsilon $   Include numerator and (inverse) denominator as main effects, ratio as interaction term.    Are my interpretations here correct?


I’m not sure how to read the expiry date on my British Passport, it states as follows; Date of expiry 26 Mar/Mars 23 The date of issue states; 27 Dec/Dec 12 It doesn’t appear to state either the issue or expiry year. Can anyone advise me on this. Thank you.

The date in my UK passport isn't in the usual format (day, month, year) it shows as-  Date off issue 20 DEC /DEC 10 Date of expiration 20 DEC /DEC 20  bit confusing but I'm guessing it means it expires in Dec 2020..can anyone confirm this?


I'm trying to create a wedding invitation but I'm struggling to get the same effect as the example one I've seen on a website.  How would I create the same background effect? I've tried using the gradient tool in Photoshop, but it doesn't seem to create the same effect.    Thanks!

This has been bugging me for ages. I want to recreate the shadows that are on the background of this image. Whenever I attempt to recreate something like this the shading ends up looking very amateur no matter how much noise or blur I add or how many layers I introduce. I would really appreciate help on this!


These pop-ups keep appearing on my Android phone when browsing Stack Exchange sites. No matter what I choose these popups occur on every page refresh and whenever I try to view a question. I'm using Google Chrome on Android 9. I read another question that suggested ad blockers or uBlock but I think that's only for desktop browsing and is not supporting by Chrome on Android. To clarify: Even if I "Accept all cookies" the popup reappears upon refreshing the page. I can find NO WAY to stop this popup from appearing on ANY Stack Exchange site. Clicking on "Accept all cookies" makes the popup disappear. Refreshing the page or navigating anywhere else has the popup appear again. I CANNOT click on "Customize settings" it DOES NOTHING. The button changes color slightly and there is a short spinning animation on the left side of it but nothing else happens. I can only choose "Accept all cookies" -- I CANNOT REJECT THE COOKIES. And even if I accept them, the popup just comes back when I refresh. I CANNOT click on "cookie settings" at the bottom of the page. When I click this link it DOES NOTHING. The page does not change. If I switch to "full site" the link "cookie settings" still DOES NOTHING. It does not take me to another page with options. Nothing happens when I click on it. I cannot dismiss this popup permanently. I am using regular Android 9 with Google Chrome. I am not in Incognito mode and I don't have any special plugins. Here is a video of my experience:  And screenshots:   ** UPDATE ** Dismissing the popup today displays a pink banner asking me to disable my ad blocker or to click on "cookie settings" at the bottom of the page. I am using Google Chrome on Android which doesn't support plugins. There is no ad block. Clicking on "cookie settings" does not bring up any settings. Instead, it just brings up the pink banner... Which asks me to disable ad block or click on "cookie settings"... Which brings up the pink banner...

Lately I've been seeing this cookie popup that blocks a lot of the screen.  When I try to do the "manage cookies" thing, all it shows me are several categories, with a green oval containing a black circle to the right of each.  Clicking on that oval makes it disappear.  Clicking on the same spot again makes it reappear.  But I see no indication as to which state is off or on. So how can I make this popup go away, never to bother me again?  Or failing that, could you at least provide some indication as to what those buttons do?  Like maybe simple text saying "Off" or "On"?


Dismissing the little popup box advertising the new "follow" should be network-wide, rather than bothering me on Each And Every Site. :-) (And the same for other future new features...)

We are happy to announce that the  follow question and answer feature is now live across the Network, including Stack Overflow, all Stack Exchange sites, and all Meta sites. (International Stack Overflow sites will have it turned on in a day or two once we have translations all set.) You can follow any question or answer (that you did not author) by clicking on the [follow] button that is shown in the menu immediately below the post (alongside the [share] button):    After you have followed a post, you will get inbox notifications for all new answers (in the case where you followed a question), comments, edits, and notices. You will not receive notifications for any action that you performed. As was mentioned in the earlier post, we are not making changes at this point to the notifications received by a post owner, or due to @mentions. The initial release had been planned to only include question following. Thanks to many folks who chipped in over the past few weeks, we are happy to release both question and answer following at the same time. These are available in both the regular and mobile views. We are still planning on two more related releases:  Follows profile tab and question listing filter: A tab for follows will be added to your user profile activity page. Each user will be able to view this tab that will provide a listing of followed questions and answers, with standard sorts, and the ability to unfollow from the listing. Users (with the exception of moderators and authorized staff) will not be able to see this information about other users (nor will it be made public in the API, SEDE, or data dumps). We will be renaming the Favorites feature to Bookmarks. As we mentioned in the preview post, the feature will be the same as Favorites, with the name and icon updated to more accurately represent user expectations and usage. And you will be able to both "bookmark" and "follow" a question.  We hope that this new feature will allow you to have better access to the content that you care about and want to keep tabs on. Update (June 11, 2020): The user profile tab and the rename of Favorites to Bookmarks have been released.


I would welcome a status such as 'I'm in Holiday' in the profile.  So for example, badges like 'Fanatic' would still be possible for people who can not visit the website for 100 consecutive days. Also, the other people would know the reason why someone is not available. Of course, this status would only be an option - maybe something like in Skype.  What do you think?

I´m posting this because I have some active questions in SO and I´m leaving for the weekend and wont have internet until monday or tuesday.  SO is a very active site and I hate no to answer/thank/comment people who are kind enough to answer my questions.  I think an "away" indicator like an out of office reply would be a really nice feature to add for "politeness" sake.


I was reading Microsoft documentation and came across bitwise exclusive OR operator. Could someone explain what does operator ^ represents in code below? I assume it is not a pointer as it would be * rather than ^.  private:         Windows::Web::Http::HttpClient^ httpClient;         Windows::Web::Http::HttpResponseMessage^ response;

I just came across this code and a few Google searches turn up no explanation of this mysterious (to me) syntax.  Hashtable^ tempHash = gcnew Hashtable(iterators_);  IDictionaryEnumerator^ enumerator = tempHash->GetEnumerator();   What the heck does the caret mean? (The gcnew is also new to me, and I asked about that .)


When Batik creates a SVG file it starts with:  <!DOCTYPE svg PUBLIC '-//W3C//DTD SVG 1.0//EN'           'http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd'>   When that is in there the Xerces call SAXParserImpl.parse() takes about 20 seconds to complete. If I remove that line it completes in well under a second.  Is there some way to tell SAXParserImpl to not go read the url? (I can't find a way in Batik to not write the DOCTYPE).  I'm in Java.  thanks - dave

When I parse my xml file (variable f) in this method, I get an error      C:\Documents and Settings\joe\Desktop\aicpcudev\OnlineModule\map.dtd (The system cannot find the path specified)   I know I do not have the dtd, nor do I need it.  How can I parse this File object into a Document object while ignoring DTD reference errors?  private static Document getDoc(File f, String docId) throws Exception{     DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();     DocumentBuilder db = dbf.newDocumentBuilder();     Document doc = db.parse(f);       return doc; }


I deleted a question 19 hours ago and just received and e-mail informing me that it was being edited. I'm concerned that my unanswered questions aren't really being deleted although they they no longer show on my account.

What circumstances can cause a question or answer to be deleted, and what does that actually mean?    How can a post be deleted? When can't I delete my own post? Can I still see my post even after it's deleted? Can I see a list of my deleted posts? How can I undelete one of my posts? What does deletion mean for a post? How do votes to delete work? What are the criteria for deletion? What else should I know about deleted posts? If I flag my question with a request to delete it, what will happen?       For more information, see the articles about  and  in the .


Reason for the refusal is inconsistent bank statement and they are not statisfied by my income, I had applied for 40 days visit visa.

The UK Visas and Immigration Directorate publishes  that provides helpful tips that can result in successful visa applications. Section 2 of this guidance opens is entitled "other documents you may want to provide" (emphasis mine).  Section 2: other documents you may want to provide – all visitors This section provides guidance on the types of documents that you may want to provide to help us consider your application against the Immigration Rules. Previous travel documents/passports, which show previous travel. Financial documents showing that you have sufficient funds available.  These must clearly show that you have access to the funds, such as:  bank statements building society book proof of earnings such as a letter from employer confirming employment details (start date of employment, salary, role, company contact details) where a third party (who is either in the UK or will be legally in the UK at the time of your visit) is providing financial support to you e.g. a business, a friend or a relative, documents to show that they have sufficient resources to support you in addition to themselves and any dependant family should be provided   The first item is "bank statements" and this ties in with the , which says...  evidence that you can support yourself during your trip, eg bank statements or payslips from the last 6 months  (Note 'eg' is a Latin abbreviation meaning "for example"; this appears to be optional rather than a fixed requirement.) Question: How should someone interpret this such that the chances of success are maximized? How many statements should I submit? What are they looking for and what do my bank statements tell about me?


I'm totally new to Perl, but I'd like to try it out. I read about two rival distributions available for Windows platform (I guess there's just Perl on other OSes :).   says that  comes with additional development tools to compile CPAN modules if necessary. It sounds pretty good to me.  It also says that  has a lot of prepackaged modules which are easier to install with PPM. It sounds great too!  There's a clear trade-off between those two. And I wonder: What should I pick to get started? If I pick one how hard, is it to migrate to the other?    I gave both distributions a run for a couple of weeks. I actually liked both which is a good thing! One can't go wrong with either of these. I ended up going with ActivePerl simply because it comes with offline documentation(in HTML) - a great life-savior for those who are on the road or just not always connected. It was super-easy for me to get started with Perl language while I was on vacation when I wasn't always online.  Strawberry Perl is at least as great if not greater. So I can totally recommend it, too. And I have to say one should just learn Perl - it's a very beautiful language. Give it a try!

The  web site provides references to several Perl distributions for MS Windows.  For a long time I have been using ActivePerl from   but recently I switched to  .  IMHO The only advantage that Active Perl still has over Strawberry Perl is the fact that it comes with Perl Tk which means its easy to install   the graphical debugger. Other than that, I think Strawberry Perl has all the advantages.


Hi I try to update Ubuntu 20.10 to 21.04 but they showing up to date   Please help me regrading this, Thank you.

Today is the release of Ubuntu 21.04 (Hirsute Hippo). And I can't update to this version. And also I selected ‘Notify me of a new Ubuntu version’ and changed it to ‘For any new version' on the Updates tab on Software & Update, but it's still not working. In addition, in the terminal, I've written: sudo do-release-upgrade -c  And output was: Checking for a new Ubuntu release No new release found.  What should I do?


Is cafe an English word or a misspelling of café? The same goes for touche and touché.  This isn't the same as  since I'm asking if cafe is a English word, not if I should use a diacritical mark on the "e".

You can see in the  that the word resumes is mentioned — not résumés or résumés.  What should be the common practice here? What about other words like café?