My laptop does not have enough space to Install Ubuntu and I need to Install it on a USB Flash Drive. How do I install it?

If you are hurrying to reply, System → Administration → StartUp Disk Creator -- no, that's not what I'm talking about.   I want to try Ubuntu 11.04's Unity without touching my existing Ubuntu install.  To do this, I need to install the nVidia drivers first (sigh).  To do this, I need changes to persist a reboot.  To do this, I need to really install Ubuntu on a USB key.  How do you do that?    What I tried   I tried to make a USB key from , then boot from it, then choose "Install Ubuntu." The installer refused to install to the installation media itself. I tried, from my installed copy of Ubuntu:  sudo kvm /dev/sdb --cdrom .cache/testdrive/iso/ubuntu_natty-desktop-i386.iso   ...but the installer didn't detect the disk properly.


I deleted all caches from Finder/Library/Caches and that barely did anything, how do I clean this up? please help

Every few days I get notices on my MacBook that it's running or run out of hard drive space. Curiously, restarting the computer will enable me to recover gigabytes of space (this past time, it was able to recover about 2.2GB). However, I can't identify anything in my personal activity that consumed that space.  It's possible that it's a rogue iTunes podcast or a huge software update that my Mac is automatically downloading - would either of these reclaim the space upon a restart?  One possibility that I can think of is that FileVault has some sort of disk leak, allocating but not freeing files. Does this make sense? Is there a tool that I can run to determine where this space is going? Assuming it is FileVault, should I try to disable it? What's the best way to turn of FileVault on a nearly full computer?


In Terraria I'm thinking of entering Hardmode but I never feel confident enough or I haven't explored much of my world. I've got full molten armour and I need just the blade of grass to craft the Nights edge. What should I do in defense wise? For example, I don't want my jungle corrupted like I want my home/base invaded by monsters all the time. What should I do to protect it like lock it down?

So I have never actually even tried to go into Hardmode yet, for the simple reason that I've never truly felt fully prepared for the challenges that await me once I enter the Hardmode World...coupled with nostalgia for my old world, but setting that aside...  What should a player have before they enter Hardmode?  How much of the map should be explored before they enact this permanent map change?  What essential resources should the player concern themselves with preserving before the transformation?    In short, how should I prepare for Hardmore?   Important Note - I do not need help preparing for the Wall of Flesh.  I already know that I need a battle platform stretching the length of Hell and I have the gear to fight it, I am more worried about preparing the entire rest of my world.


I'm trying to run Beamer to get a listing in a presentation. I'm getting a mysterious error message that looks like:  ! Missing number, treated as zero. <to be read again>                 \let  l.221 \end{frame}  ? H A number should have been here; I inserted `0'. (If you can't figure out why I needed to see a number,  look up `weird error' in the index to The TeXbook.)   Part of my problem is that \let is not in my code, this must be the expansion of a macro.  My immediate question is "How can I get TeX to give me information about what macros it was expanding when it encountered the error?"  That might give me a clue about what to do next.  More context: I'm trying to use an algorithm listing of json objects in Beamer.  I have the following defined in my header:  \usepackage{algorithmicx} \usepackage{algorithm} \floatname{algorithm}{Example} %-------------------------------------------- %JSON listing mode, from % https://tex.stackexchange.com/questions/83085/how-to-improve-listings-display-of-json-files#83100  \usepackage{listings} \usepackage{xcolor}  \colorlet{punct}{red!60!black} \definecolor{background}{HTML}{EEEEEE} \definecolor{delim}{RGB}{20,105,176} \colorlet{numb}{magenta!60!black}  \lstdefinelanguage{json}{   basicstyle=\normalfont\ttfamily,   numbers=left,   numberstyle=\scriptsize,   stepnumber=1,   numbersep=8pt,   showstringspaces=false,   breaklines=true,   frame=lines,   backgroundcolor=\color{background},   literate=    *{0}{{{\color{numb}0}}}{1}     {1}{{{\color{numb}1}}}{1}     {2}{{{\color{numb}2}}}{1}     {3}{{{\color{numb}3}}}{1}     {4}{{{\color{numb}4}}}{1}     {5}{{{\color{numb}5}}}{1}     {6}{{{\color{numb}6}}}{1}     {7}{{{\color{numb}7}}}{1}     {8}{{{\color{numb}8}}}{1}     {9}{{{\color{numb}9}}}{1}     {:}{{{\color{punct}{:}}}}{1}     {,}{{{\color{punct}{,}}}}{1}     {\{}{{{\color{delim}{\{}}}}{1}     {\}}{{{\color{delim}{\}}}}}{1}     {[}{{{\color{delim}{[}}}}{1}     {]}{{{\color{delim}{]}}}}{1}, }   The code for the frame in the Beamer file is:  \begin{frame}{Proc4 Messages}   \begin{columns}     \begin{column}{0.5\textwidth}       \begin{algorithm}     \begin{lstlisting}[language=json]       {         app:"ecd://coe.fsu.edu/EPLS/AssessmentName",         uid:"Student/User ID",         timestamp:"Time at which event occurred",         verb:"Action Keyword",         object:"Object Keyword",         data:{           field1:"Value",           field2:["list","of","values"],           field3:{part1:"complex",part2:"object"}         }       }   \end{lstlisting}       \end{algorithm}     \end{column}     \begin{column}{0.5\textwidth}       \begin{itemize}        \item Application header defines vocabulary used in other           fields.        \item ...         \item Data field can hold any number/kind of object.       \end{itemize}     \end{column}   \end{columns} \end{frame}   The same listing runs fine in another document that uses article rather than beamer style, and the rest of the frame is pretty standard.

I want to put some PHP code in my slide with the package listings but I have this error message:  Argument of \frame has an extra }.<inserted text>\par }   My latex code :   \documentclass{beamer}  \usepackage[utf8]{inputenc}  \usepackage[T1]{fontenc} \usepackage[frenchb]{babel} \usepackage{setspace} \usepackage{color} \usepackage{listings}  \usetheme{CambridgeUS}   \begin{frame} \begin{large}     Contexte : \newline \pause \end{large}  \begin{itemize}     \item Avertir Drupal \end{itemize} \begin{lstlisting}  // Gestion du contexte ete2013 // Utilisation d'un nouveau template if (%variables['ctpage'] == "ete2013") {     variables['template_files']=array('page-ete'); } \end{lstlisting} \end{frame}


I am using below command to display log data for last 10 mins. It works fine if the month stays same however when month is changed it doesn't show any data.  awk -v d1="$D1" -v d2="$D2" '$0 > d1 && $0 < d2 || $0 ~ d2' /home/user.log   Works fine if,  D1="Aug  1 12:00:00" D2="Aug  1 12:10:00"   But doesn't show any data if,  D1="Jul 31 11:55:00" D2="Aug  1 00:05:00"   P.S I am using AIX

I need to display lines with Error occurred in last 10 minutes of a log file.   Aug 26 10:50:42 Normal line. Aug 26 10:51:23 Normal line. Aug 26 10:55:33 Error line. Aug 26 10:56:45 Normal line. Aug 26 10:58:12 Error line. Aug 26 11:02:31 Normal line. Aug 26 11:03:32 Normal line. Aug 26 11:04:11 Normal line.   Suppose above sample of log file. I want to display only following two lines  Aug 26 10:55:33 Error line. Aug 26 10:58:12 Error line.   I am using AIX.


Help with identify this story please?  An alien race (anthropologists) visit earth and find all life extinct. They find a way to recreate life up to a certain point in the past timeline. As they move the recreation point closer and closer to present day, they encounter more advanced humans. The initial humans are confused, the later ones are able to understand the situation more easily and the last/most recent one understands the whole situation in the blink of an eye and disappears instantly (hence going out of the aliens control).

I'm trying to locate a short sci-fi story I read years ago about a human that is "resurrected" by an arrogant and malignant alien species that discovers him in a "museum" on an earth where the inhabitants, though very advanced, had been wasted by a close encounter (I believe) with a neutron star. He is the third or fourth human they "reconstruct" and it turns out that he is an advanced mentalist, disappearing at the moment of his "resurrection". He outwits the aliens and eventually tricks them into plunging their ship into the sun in order (they think) to prevent him from finding out where they come from. Any suggestions?


I know there is a bijection from $(0,1) $ to $(0,1] $.  Are there functions  $f,g:(0,1) \to (0,1] $  where $f$ is a continuous surjection and $g$ is a continuous bijection?

Does there exist a continuous bijection from $(-1,1) \to (-1,1]$?   Suppose that $f$ is a continuous bijection from $(-1,1) \to (-1,1]$.Then $f^{-1}(1)=a$ where $a\in (-1,1)$.  Since restriction of a continuous map is continuous so $f|_{(-1,a)\cap (a,1)}$ is  a continuous map its image is $(-1,1)$.  But it is not giving anything.Please give some hints.I am unable to proceed.


Basically, I am wondering if there is a way to automatically run a function when an element becomes hidden or visible, not on a user click but automatically in another script.  I don't want this to just run one time, because the elements (such as a slider) constantly change from visible to hidden.  Would this be something that jQuery can do with bind? Such as binding the element's visibility to a function (I don't know how to write this)  If you need me to elaborate more on what I'm trying to do, let me know. Thanks  Pseudocode:   $('#element').bind('display:none', function); function(){     //do something when element is display:none }  $('#element').bind('display:block', function2); function2(){     //do opposite of function }

I'm loading elements via AJAX. Some of them are only visible if you scroll down the page. Is there any way I can know if an element is now in the visible part of the page?


I want to remove all empty lines from a file. Even if the line contains spaces or tabs it should also be removed.


How can I use <=, >=, >, and < in bash?  Instead of:  if [[ $arg1 -ge $num1 && $arg2 -le $num2 ]]; then      ... fi   Have something more like:  if [[ $arg1 >= $num1 && $arg2 <= $num2 ]]; then      ... fi

In Bash, two integers can be compared using conditional expression     arg1 OP arg2      OP is one of -eq, -ne, -lt, -le, -gt, or -ge. These   arithmetic binary operators return true if arg1 is equal to, not equal   to, less than, less than or equal to, greater than, or greater than or   equal to arg2, respectively. Arg1 and arg2 may be positive or negative   integers.   or arithmetic expression:     <= >= < > comparison      == != equality and inequality   Why do we have two different ways for comparing two integers? When to use which?  For example, [[ 3 -lt 2 ]] uses conditional expression, and (( 3 < 2 )) uses arithmetic expression. Both returns 0 when the comparison is true  When comparing two integers, can these two methods always be used interchangeably? If yes, why does Bash have two methods rather than one?


I think I passed the reference of value to hashmap,then after I change the value outside,the value in the hashmap should also be changed.      Integer key=new Integer(0);     Integer value=new Integer(3);     HashMap<Integer,Integer> hm=new HashMap<Integer,Integer>();     hm.put(key, value);     System.out.println(hm.get(key));     value=null;     System.out.println(hm.get(key));

I always thought Java uses pass-by-reference. However, I've seen a couple of blog posts (for example, ) that claim that it isn't (the blog post says that Java uses pass-by-value). I don't think I understand the distinction they're making. What is the explanation?


I know about the famous identity $$ e^{ix}=\cos x + i\sin x $$ I have proved the above identity by comparing the Maclaurin series of $e^{ix}$,$\cos x$ and $\sin x$. But I want to know about other proofs of this identity. I have no idea about any such proofs. Any help would be appreciated.

Could you provide a proof of Euler's formula: $e^{i\varphi}=\cos(\varphi) +i\sin(\varphi)$?


im a new  to blender as well as 3d modeling.... i have 3d model that i make from other 3d photogrammetry software such as remake.. but the model is not nice... so i want to ask .... is it possible if i want to export the model into blender then map the image onto it.. but the problem is the triangular mesh is too many ( because the model is tree model capture from sequence of photos).. or any solution ..as next i need to export the model into unity to build vr.. thanks..

I am creating a model of a glass and I would like to put a drawing on it (a png picture).  I know how to do it using Blender Render, but not with Cycles Render. Help :)


I have a text file like        aaaa     aaaa     aaaa     aaaa     ....  I use the sed to replace the string of "aaaa" with "bbbb", the command is       sed -i "/aaaa/c\bbbb"  mytextfile         but I want the sed to stop processing when it finds first match.The output will be like this       bbbb     aaaa     aaaa     aaaa     ....   Anybody tells how to do that?

I would like to update a large number of C++ source files with an extra include directive before any existing #includes. For this sort of task, I normally use a small bash script with sed to re-write the file.   How do I get sed to replace just the first occurrence of a string in a file rather than replacing every occurrence?  If I use  sed s/#include/#include "newfile.h"\n#include/   it replaces all #includes.   Alternative suggestions to achieve the same thing are also welcome.


The commutative law of multiplication states that:     If '$a$' and '$b$' are any whole numbers,   then   '$a · b = b · a$'.   I've been looking for why multiplication has this property and how is saying that 3 times 4  the same thing as saying  4 times 3. I've found two interpretations:   $3 \cdot 4 = 12$ and $4 \cdot 3 = 12$  so, $3 \cdot 4 = 4 \cdot 3$, Think of $3\times 4$ as the area of a rectangle with width $4$ and height $3$.  If you rotate the rectangle by $90^\circ$, the area is unchanged, but now the width is $3$, and the height is $4$.  So, $3\times4 =$ area of rectangle = area of rotated rectangle $= 4\times3$.   These explanations don't seem to show why multiplication has this property but are showing us a way to make it intuitive and, thus, accept it as common sense.  Is there a better way to show that multiplication is fundamentally commutative?

$ab = ba$  This is, inherently, true. Some texts drop it like an axiom without any justification. But I'm a bit curious where it stems from or basically why/how it works. If anyone could enlighten me a bit further, I'd be most grateful. Peano axioms? From set theory? Help.  What bugs me with this definition is it's real world "application":  Let's say I have a power output of 5 W ( $kg\cdot m^2 \cdot s^{-3}$) and I want 30% of that power output (to have some units and natural context).  Naturally, 30% is 30 1/100 (% is the unit). For simplicity, let's express that as:  $30$%$ = 30/100 = 3/10 = 3d$ where $d = 1/10$, a simpler unit (because %W would look... Wrong?).  So 30% of power is then $5 W \cdot 3d$, and we can force it to "make sense" if we associate d with W or basically scale the unit of power by d (which is intuitively understood as being 10 times smaller then the output of 1 W) $dW$. And we want to scale these 5 units of $dW$ three times.  $5 dW \cdot 3$  But the commutative property says it is the same as scaling 3 units of $dW$ 5 times or:  $3 dW \cdot 5$  And the result is the same. This is the bit that hurts my head, the fact it is the same. I try to interpret the same as, for example 50 J of work, it's either applying 50 N over 1 m of distance or 1 N over 50 m of distance.    Down here is additional stuff I think I have (you don't have to read it if you know how to answer immediately). I don't claim it's correct, if anyone parses this information, feel free to correct me.  $m\sum\limits_{i=1}^{n}{1} = n\sum\limits_{i=1}^{m}{1}$  This is how I've been trying to break it down, as it is repeated addition. It is repeated $n$ times and multiplied by $m$, and reverse on the right side. There is $x = m - n$, so when I multiply $n$ $m$ times, each repeated addition of $n$ lacks exactly $x$ to $m$.  $mn = nm$  $x = m-n$  $m(m-x) = (m-x)m$  $m^2 - mx = m^2 - mx$  $ true $  And yes, sadly, I realise that I am using the very property I'm trying to prove ($xm$ shifted as $mx$ on the right-hand side.)  And it even calls in the distributive property of multiplication over addition which I derive (for myself, informally) from the very nature of multiplication and the way we "process" numbers:  For example, number $55$ times $2$  $55 = 5 \cdot 10^1 + 5 \cdot 10^0 = 5 \cdot 10 + 5 \cdot 1$  $(5 \cdot 10 + 5 \cdot 1) \cdot 2$  This is the basis of our positional notation which appends digits of varying orders of magnitude or units together in a way it makes "sense". Each one is b times bigger than the one to the right. Basic stuff. It is why I expressed 10 and 1 explicitly, those are what I consider units in this case.  Now, from the definition of multiplication, which is at its heart just repeated addition, it is truly the same if you add together $2$ $50$ times and then again $5$ times or "all at once" (figuratively, we are always doing the former mentally) $2$ $55$ times.  That added together gives 110, which is true.  To me, the distributive property (in case of integer multiplication) is a repercussion of the very definition of multiplication which is repeated addition (evading strict concepts). I am not certain whether this is a good way to look at it.


I wanted to see if a neural network could learn the identity function using the MNIST handwritten dataset.  Here is the full code  import keras from keras.datasets import mnist from keras.models import Sequential from keras.layers import Dense from keras.optimizers import RMSprop  batch_size = 128 epochs = 20 (x_train, y_train), (x_test, y_test) = mnist.load_data() x_train = x_train.reshape(60000, 784) x_test = x_test.reshape(10000, 784)  model = Sequential() model.add(Dense(784, activation='relu', input_shape=(784,))) model.add(Dense(784, activation='relu')) model.add(Dense(784, activation='relu')) model.add(Dense(784, activation='relu')) model.summary() model.compile(loss='mean_squared_error',             optimizer=RMSprop(),             metrics=['mean_absolute_percentage_error'])  history = model.fit(x_train, x_train,                     batch_size=batch_size,                     epochs=epochs,                     verbose=1,                     validation_data=(x_test, x_test)) score = model.evaluate(x_test, x_test, verbose=0) print('Test loss:', score[0]) print('Test MAPE:', score[1])   and the output  **4 dense layers** Epoch 20/20 60000/60000 [==============================] - 50s 840us/step - loss: 456.7581 - mean_absolute_percentage_error: 351097677.7045 - val_loss: 523.7151 - val_mean_absolute_percentage_error: 504905991.0656 Test loss: 523.7150838867187 Test MAPE: 504905988.5056   What I can't quite get my head around is why training cannot find the perfect solution to the problem and why it takes so long to even get close to it? Even with one dense layer the exact solution cannot be found:  **1 dense layer** Epoch 20/20 60000/60000 [==============================] - 16s 268us/step - loss: 180.6187 - mean_absolute_percentage_error: 209296481.2373 - val_loss: 167.9543 - val_mean_absolute_percentage_error: 192590419.9936 Test loss: 167.954341796875 Test MAPE: 192590420.1984   Conceptually I can see that there is a solution space (not just the exact identity function) as it is likely there are some pixels that have the same value as each other in all the images which could be swapped in the training set at no loss (0's around the edge for example). With the knowledge that this is a local minimum can I learn anything from this to guide me out rather than playing with hyperparameters until I find something better?

I'm training a neural network but the training loss doesn't decrease. How can I fix this?  I'm not asking about overfitting or regularization. I'm asking about how to solve the problem where my network's performance doesn't improve on the training set.    This question is intentionally general so that other questions about how to train a neural network can be closed as a duplicate of this one, with the attitude that "if you give a man a fish you feed him for a day, but if you teach a man to fish, you can feed him for the rest of his life." See this Meta thread for a discussion:   If your neural network does not generalize well, see:


For a sample of size $n$ of non-normal random variables $x_1,...,x_n$. Is it possible to know which distribution the sample variance estimator follows?  Details: The distribution of $x_i$'s is not known. The only thing I know is that this $n$-dimensional sample was taken from a population with mean=0 and std=1. I also don't know about the distribution of the population.  thanks!

I am sampling from a parameter with unknown distribution. I would like to calculate a 95% CI for the standard deviation of the sample.   @cardinal provides a nice general solution for calculating a CI in his [answer] to my previous question,  . And @erik-p provides an estimate of the standard deviation of the variance of the sample.  However, in order to calculate the 95%CI for the sample variance, it seems that I need to know the distribution of the sample variance. Is it possible to calculate such an estimate without knowing the distribution from which the sample was taken?  A related question is


In 9th grade I had an argument with my teacher that   ${i}^{3}=i$  where $i=\sqrt{-1}$  But my teacher insisted (as is the accepted case) that:  ${i}^{3}=-i$  My Solution:  ${i}^3=(\sqrt{-1})^3$  ${i}^3=\sqrt{(-1)^3}$  ${i}^3=\sqrt{-1\times-1\times-1}$  ${i}^3=\sqrt{-1}$  ${i}^3=i$  Generally accepted solution:  ${i}^3=(\sqrt{-1})^3$  ${i}^3=\sqrt{-1}\times\sqrt{-1}\times\sqrt{-1}$  ${i}^3=-\sqrt{-1}$  ${i}^3=-i$  What is so wrong with my approach? Is it not logical?  I am using the positive square root. There seems to be something about the order in which the power should be raised? There must be a logical reason, and I need help understanding it.

I know there must be something unmathematical in the following but I don't know where it is: \begin{align} \sqrt{-1} &= i \\\\\ \frac1{\sqrt{-1}} &= \frac1i \\\\  \frac{\sqrt1}{\sqrt{-1}} &= \frac1i \\\\  \sqrt{\frac1{-1}} &= \frac1i \\\\  \sqrt{\frac{-1}1} &= \frac1i \\\\  \sqrt{-1} &= \frac1i \\\\  i &= \frac1i \\\\  i^2 &= 1 \\\\  -1 &= 1 \quad !!? \end{align}


Apologies for my posting tone, but I'm leaving this computer now and wanted to make clear that there's a problem. Note that I didn't use the incognito mode when logged into my Open-ID provider because of some SO-unrelated issues with it.  Logging out of SO has always puzzled me. The recent change might be an improvement, though the logout link keeps to be hidden nearly as hard as before. Nonetheless I see I've been smart enough to find it (shouldn't I get a golden badge for this hard work?) and logged out of SO.  The sad thing is that I'm still logged in here on meta. You can argue it's a different site, but seriously:   Is it? Should we care? Does it make any sense to log out of one sub-site and stay logged in in the others?   An answer like "" is non-sense. In addition to the fact that that Google does it, I'd say that it's pretty easily doable (make the cookie dependent of a counter incremented on each logout or whatever, the crypto site guys surely know better).   In similar questions I've seen, the answers seem to miss some problems:   There should be a real global logout, which means   it should log you out of all SO sites no matter if you've failed to use the incognito mode no matter if the browser supports it no matter if the cookies get backed up somewhere in the meantime no matter on how many devices you logged in    Simply tell the server that all the current cookies are invalid. That simple, really.

Is a "log out from every SE site in the network" button technically feasible?  With so many SE sites popping up, it would be a very useful feature.  Edit: has this been implemented now, as @Ben suggests in his comment? I've lost track.


I have this recurrence relation to solve :  $T(n) = T(\sqrt n) + 1 $  I have tried to expand the recursion but I stopped here:  \begin{align} T(n) &= T(n^{\frac12})+1\\      &= T(n^{\frac14})+1+1\\      &\text{after $i$ replacements I have}\\      &= T(n^{\frac1{2^i}}) + i\\ \end{align} I know that $T(1) = 1$  And now? How can I get to the solution?

This looks like a question asked , but it isn't.  $$T(n)=\begin{cases} T (\sqrt{n}) + 1 \quad & \text{ if } n>1 \\  1 & \text{ if }n=1\end{cases}$$  My professor gave this to me in class yesterday. This is where I'm stuck:   $$T(n) =  T(n^{1/2})+1 =  T(n^{1/4})+2 = T(n^{1/8})+3 = \dots =   T(n^{1/ 2 ^k})+k$$  Now this will continue till  $$n^{1/ 2 ^k}=1$$  How do I proceed ahead? If I take log on both sides, then RHS becomes zero. How do I solve the relation?  I don't want to use the Master theorem, I want to know where and why am I stuck.


I'm working on a system to automatically back up my computer using rsync and the Google Drive app (I have a Macintosh computer). (This app creates a directory whose contents are saved to the Google Drive cloud.) The idea of the backup system is to (automatically) copy files to the Google Drive directory (using rsync, preferably) then upload the directory to the cloud.  This system has a major drawback, however: memory waste. Every file that I backup has to be copied to a second location in my computer, doubling the space the file uses. It would be much more memory efficient to make hard links instead of copies. I would like to duplicate my directory tree using hard links, then update the duplicate when the original changes.  Can I use rsync to make hard links instead of copies? I think this might be possible with the link--dest= option, but I can't figure it out.  Edit: A few clarifications, in response to feedback.    This question has been listed as a duplicate of  . I don't understand why the questions are the same. I gather that the similarity has to do with using the --link-dest= option to create hardlinks. But this is what I don't understand how to do! So I'm not satisfied with the duplicate question. It seems like using --link-dest= to make hardlinks only works if you already have a backup to compare it to. I'm not computer proficient compared to the users of this site. If the answer to my question is something like "this is easy, just read the man page for rsync more carefully" or something like that, I'll do it. I'm perfectly happy using some other bash utility to achieve the functionality I'm looking for! I just happen to like rsync, but I'm open to other options. JdeBP has suggested using pax, for example.

I'm using rsync to backup some of my files:  rsync -aEN --delete --link-dest="$CURR/" "$SOURCE/" "$NEW/"  The --link-dest option works fine with most files, but not with symlinks. When I was writing a clean-up script for old backups, I noticed that unchanged symlinks are not hard-linked, but rather copied.  Now I'm wondering: Is there a way to make rsync hard-link unchanged symlinks as well? And if not: Is it intentional or a bug in rsync?  I'm using rsync version 3.1.1 on Mac OS 10.11.  Edit:  It seems to be a problem in Mac OS X. For some reason HFS+ seems not to support hard-links to symlinks.


As far as I understand, the Heisenberg uncertainty principle states that the more one of the conjugate quantities are known, the less the other is known. So for instance, if the velocity of a particle is known more precisely, its location will become known less precisely.  I also read somewhere that it's because if you direct some ray at the moving particle, the ray will reflect, giving the former position of the particle, but the whole collision between the ray and the particle changes the particle's momentum, thus only one can be measured at a time which is the Heisenberg uncertainty principle.  In that case, if there is an indefinitely precise measuring device that can detect the particle's position and velocity at the same time, can the Heisenberg uncertainty principle disproved? Also, does the Heisenberg uncertainty principle apply only to subatomic particles, or large objects too?

From what I understand, the  states that there is a fundamental natural limit to how accurately we can measure velocity and momentum at the same time. It's not a limit on equipment but just a natural phenomenon.  However, isn't this just an observational limit? There is a definite velocity and momentum, we just don't know it. As in, we can only know so much about the universe, but the universe still has definite characteristics.  Considering this, how do a wide range of quantum mechanical phenomena work? For example, quantum tunneling - its based on the fact that the position of the object is indefinite. But the position is definite, we just don't know it definitely. Or the famous light slot experiment? The creation of more light slots due to uncertainty of the photon's positions?  What I am basically asking is why is a limit on the observer, affecting the phenomenon he is observing? Isn't that equivalent to saying  because we haven't seen Star X, it doesn't exist? It's limiting the definition of the universe to the limits of our observation!


I have temperature data of July 1991 to 2007, and wants to find the Confidence Interval at 95%, which distribution is best fit the data, Z or T. Please give me reason also. Thanks

I have temperature data of July 1991 to 2007, and wants to find the Confidence Interval at 95%, which distribution is best fit the data, Z or T. Please give me reason also.    minTemp = 14.4444, maxTemp = 38.3333, SizeofData = 527, (17 years) hist(July, 20), histfit(July, 20);


So if Harry is descended from Ignotus and Voltemort from Peverrels, does that make them long lost cousins?

I know that he was related to      Ignotus Peverell   From CoS we know he was a "spiritual" heir of Gryffindor (aka True Gryffindor) - but so was Neville from DH events.  And he was born in Godric's Hollow.  But is there any information to confirm or deny whether Harry Potter was literally descended from Godric Gryffindor?


What is the Algorithm for getting truth table for the Boolean function (Near bent or semi bent functions)?\  Example: If I have a Boolean function over $\mathbb{F}_{2^5}$, how to write the function $f(x)=Tr((x)^{3})$ in truth table manually. Is there any algorithm for it or we have the inbuilt function in Java.

is a method to simplify Boolean algebra expressions in two different notations sum-of-products() and product-of-sums(). I need to find a minimized boolean expression in  for a truth table. Is there a solution?    A solution is simplifying the boolean algebra expression in CNF or DNF then converting it to ANF. But is it minimized?    Is there a software to convert CNF boolean algebra expressions to ANF?


My sneak skill is currently 49 and I want to get it to 100. Keeping my joystick pushed forward while unseen, how long would it take to get to 100? I'm playing on Xbox.

I noticed that you don't get better at sneaking by simply sneaking around anymore (maybe I'm wrong and it just goes really slowly?).   The only way to get better that I discovered was to successfully attack enemies while hidden.  Are there other ways to increase your sneaking skill and what are they?


I know that a conjugacy class looks like this:  $C_y = \{x \mid x = g^{-1} y g \}$ where $g, y \in G$  I also know a dihedral group looks like this:  $D_n = \{e, b, b^{2}, ..., b^{n-1}, a, ab, ..., ab^{n-1}\}$  How can I therefore list all the conjugacy classes for the general case?  Naive me just wrote this down as the answer:  All distinct $C_y = \{x | x = g^{-1} y g \}$ where $g, y \in D_n$  Well... that's not very useful. I'm just not sure what I'm supposed to do to answer the question satisfiably.  Here's the original question:

List all the conjugate classes in the dihedral group of order $2n$ and verify the class equation.  The dihedral group is generated by two elements $r$ and $s$.   The order of $r$ is two since $r^2=e$ and $s$ is $n$ since $s^n = e$. And I know all elements can be produced as either $s^k$ or $rs^k$. How can I list all the conjugacy class?


How can I get the following font in latex? I usually the Computer Modern font in LaTeX, but I am interested to use it. In particular, I don't want to know what font it is, rather I just want to know how can I typeset in LaTeX with this font.

Is it possible to identify the font used in a specific document/picture?  Answers to this question should identify:   Possible methods to do this (perhaps one answer per method) and adequately describe how to use it (as opposed to merely stating it); Ways of finding the identified fonts, if possible (free or not); and Any prerequisites associated with the method used, if required (for example, "In order to use method X, your document has to be in format Y").   This question is meant as an FAQ, based on an . Its aim is to facilitate the community with the general procedures involved in font identification. Similar cases are solved on a per-usage basis on 's  tag.


My friend has the original iPad that runs iOS 5.1.1 and can't be updated any further. Very few apps these days are compatible with that version of iOS. The new version of VLC in the App Store requires iOS 7.  What I thought I'd do is get an old version of the .ipa for VLC that's compatible with iOS 5.1.1. I have a computer with iTunes that I wonder if I can use to transfer it to the iPad.   Are some old versions of VLC compatible with iOS 5.1.1? If yes, what's the latest VLC version that's compatible? Where can I get such .ipa files? Do I have to jailbreak the iPad in order to install such downloaded files, or can I do it without jailbreaking?

I have a 1st generation iPad and when I download apps it tells me “this requires iOS 6.0 or later” but when I go to update it tells me it's fully updated? Why is this happening, and is there any way I can fix it?


When the focus is within the text box when writing a new question, and the user presses Command + L the Insert Hyperlink box comes up. This overrides the functionality of chrome, which is to switch the focus to the address bar; it's a little annoying.  The intent is to write a post not leave the page, but it is quite jarring to see the site override Chrome's keyboard shortcut.

I navigate with Ctrl-n,p,f,b (readline/ keys), so that I don't have to move my hands too much and get  again. Is there a way to disable Ctrl-b being hotkey for bold?  Note that this is not just an Emacs thing. Standard web browsers, like Firefox and Chrome, use things like  Ctrl + K and Ctrl + L to navigate to the Google search bar and address bar respectively.


I'm a Sri Lankan passport holder. I'm planning to travel to China in January and have to transit in Malaysia. I wonder whether I can obtain a Malaysian transit visa in KLIA 2 when I'm flying back to Sri Lanka.

I am an Indian passport holder travelling from China to India via Kuala Lumpur, on Air Asia tickets bought separately. The layover is 4 hours and 30 minutes.  Do I need a transit visa?


I've noticed that when my phone is near my MacBook, I only receive notifications for Messages on my MacBook. My iPhone remains silent, and the screen does not light up.   Is this an expected behavior (feature not a bug?), and is there a way to ensure that the phone always dings and lights up for message notifications?  Thanks!

I just realized that my iPhone SE, iOS 12.3, isn't issuing the "ding" tone when texts are received. The Messages app shows a badge (small red circle) when a message arrives. The ring for a phone call works correctly.   The text tone sounds correctly in Settings > Sounds > Text Tone, Do Not Disturb is turned off, and Settings > Notifications > Messages is set to "Allow." I've restarted (soft and hard), and the Mute switch on the side of the case is in the up (sound allowed) position. Selecting another text tone has no effect, the different tone is also not issued.  What else might I try?


There is a specific word for your effort when you can't find something because of no light around. Please help?

How do you describe the following kind of 'search' in one word?  A blind man searching for a faucet in a room  OR  A normal man searching for a faucet in a dark room  Is it fumbling, scouring, scouting, scrounging, or something else?


Trying a VPS (hosting).  I have installed Ubuntu 16.04 and created a user admin. Now I'm trying: ssh admin@185.149.129.42 The prompt becomes just a $.  I try:   sudo su root   The prompt has become   root@simple_project:/home/admin#   This line is in white letters.  I try:   su admin   The prompt is in green letters:  admin@simple_project:~$    Well, in other words three cases:   white $;  white root; green admin.   I was somehow confused by case 1 for example. And I did:   su root  su admin  And I get my green letters up to the colon:  admin@simple_project:~$   This looks more familiar than just a bear $.  Could you tell me what these three cases mean? If they really mean anything.

I already read it from manual but I can't see difference..  su - change user ID or become superuser  sudo -s [command]   The -s (shell) option runs the shell specified by the SHELL environment variable if it is set or the shell as specified in passwd(5).  If a                    command is specified, it is passed to the shell for execution.  Otherwise, an interactive shell is executed.  sudo -i disappear description in manual


The output PDF while using revtex4-2 is in landscape form, how can the problem be resolved?    \documentclass[aps,prstper,preprint,groupedaddress]{revtex4-2} \usepackage{amsmath} \usepackage{hyperref} \usepackage{makecell} \usepackage{graphicx,lipsum,afterpage,caption,subfigure} \usepackage{supertabular} \usepackage{morefloats} \usepackage{tablefootnote} \usepackage[final]{pdfpages} \usepackage{import} \usepackage{filecontents} \usepackage{multirow} \usepackage{booktabs} \usepackage{siunitx} \usepackage[inline]{enumitem} \usepackage{enumitem} \usepackage{soul} \usepackage{textcomp} \usepackage{threeparttablex} \usepackage{supertabular} \usepackage{morefloats} \usepackage{ucs} \usepackage{color} \usepackage{array} \usepackage{calc} \usepackage{multirow} \usepackage{hhline} \usepackage{ifthen}   \usepackage{floatrow} \begin{document}  \title{Development and Validation}   \end{document}

This happened when I updated MikTeX to the latest version (as of time of this post) and tried the  regarding adding pdf pages to RevTeX documents. Running the code below produced text rotated by 90 degrees while commenting out the line which includes the pdfpages packages produces regularly positioned text. Note that the page number was not rotated. Can anyone reproduce this and what is the cause of this?  \documentclass[english]{revtex4-1} \usepackage{pdfpages}  % Including PDF  \makeatother \usepackage{babel} \begin{document}  Lorem ipsum dolor sit amet...  \end{document}


If you put this in the browser address bar (firefox/IE8):  javascript:alert(40.34+56.87)   Why the result comes as  97.2100000000001 when its supposed to be 97.21

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


This is just... wrong. Chrome latest, just started now.  It only seems to be happening on SO, I checked several other SE sites.

I seem to have clicked on something that changed my display preferences. The main site is now very minimalistic, with fewer controls and different fonts.  I want to change it back, but where is it?


I have two manuscripts that I am ready to submit in two different journals.   In the first manuscript, I have developed two models to be used for my research. Both of them are new and are an upgrade to the currently used models.  In the second manuscript, I have used one of the models developed in the first manuscript and have carried out an elaborate study. However, I am unsure on how to cite the first manuscript in the second.   Can I cite a submitted manuscript as "under review" in another manuscript? What's the correct procedure for citing under review works?

I want to submit two separate works to two different conferences in CS field. The conference deadlines differ only by 3 weeks and one of them would be held in November while the other in September.   The problem is that i designed an algorithm and used that in both of the works. This algorithm is not the essential part of these papers, so i can introduce it completely in paper A as a novel method and just cite and use it in paper B; or vice versa!  But the problem is that at the time of submission, both of them are just submitted works, and i'm not sure if citing a submitted work is acceptable? Especially because if i only cite and use it in paper B, the reviewers cannot read paper A to see the complete proofs. And even i'm not sure which paper may be accepted/rejected!  Also if i introduce the method in both papers as a novel method, then if both of them get accepted they will consider it plagiarism!


I have a list of class instances -   x = [<iteminstance1>,...]   among other attributes the class has score attribute. How can I sort the items in  ascending order based on this parameter?  EDIT: The list in python has something called sort. Could I use this here? How do I direct this function to use my score attribute?

I've got a list of Python objects that I'd like to sort by an attribute of the objects themselves.  The list looks like:  >>> ut [<Tag: 128>, <Tag: 2008>, <Tag: <>, <Tag: actionscript>, <Tag: addresses>,  <Tag: aes>, <Tag: ajax> ...]   Each object has a count:  >>> ut[1].count 1L   I need to sort the list by number of counts descending.  I've seen several methods for this, but I'm looking for best practice in Python.


After upgrading from 12.04 to 14.04 I could log in to my X session (albeit with really low graphics). While trying to fix the graphics, I managed to break the X session.  Now, after typing my password in the unity-greeter, the items disappear and I can only see the desktop background and the pointer. This happens for every user. I can still log in in tty's. How can I solve this?  Also, I cannot seem to be able to install nvidia-current as it tries to install nvidia-304 and it depends on old video-abi libraries. Is there a way to tell the package manager that nvidia-current should use a newer version?

When I login, nothing happens.   I am presented with my desktop wallpaper.    No Dash, no Launcher, nothing.


I changed my hostname in:  /etc/hostname   And then also changed it with:  sudo hostname MATRIX   But I experienced a problem because (and I don't know if this is related or not) none of my applications would launch, not even Terminal, the processes would launch, but just stay in the Sleeping status. So I restarted the machine and all seemed well until I ran something with sudo and I got this error message:  sudo: unable to resolve host MATRIX   Why is this the case and how can I fix it so that sudo can resolve it?    OS Information:  Description:    Ubuntu 15.04 Release:    15.04   Package Information:  sudo:   Installed: 1.8.9p5-1ubuntu5   Candidate: 1.8.9p5-1ubuntu5   Version table:  *** 1.8.9p5-1ubuntu5 0         500 http://gb.archive.ubuntu.com/ubuntu/ vivid/main amd64 Packages         100 /var/lib/dpkg/status

I want to change the OS hostname but I do not want to restart.  I have edited /etc/hostname but it requires a restart to get implemented. How to avoid this?


I recently installed ubuntu desktop and started its GUI with startx and now I want to run commands like tar lamp etc, how can i do that?

What is a terminal? How do I open a terminal window? How do I use the terminal?


Let $A$ be any $m\times n$ matrix and $I$ be the $n\times n$ identity.   Prove that $I+A^{T}A$ is invertible.

Let $A$ be an $m\times n$ matrix. Prove that $A^*A + I$ is invertible.   I'm not sure what to do because everything I try ends up at $A^*A$ again and not $AA^*$.


I am trying to compute the probability of having 4 (or more) consecutive heads in 10 coin tosses.   I tried using recursion but it led to a complicated expression so i think i did not quite manage.   I saw similar questions asked here that were solved with difficult approaches, but this problem looks like it could be solved in a couple of lines so I must be doing something wrong.  If anyone could help me understand it or propose a different approach for solving the problem i would be very grateful.  Have a nice day!

Tossing a fair coin for $N$ times and we get a result series as $HTHTHHTT\dots~$, Here '$H$' denotes 'head'  and '$T$' denotes 'tail' for a specific tossing each time.  What is the probability that the length of the longest streak of consecutive heads is greater than or equal to $k$? (that is we have a $HHHH\dots~$, which is the substring of our tossing result, and whose length is greater than or equal to $k$)  I came up with a recursive solution (though not quite sure), but cannot find a closed form solution.  Here is my solution.  Denote $P(N,k)$ as the probability for tossing the coin $N$ times, and the longest continuous heads is greater or equal than $k$. Then (For $N>k$)  $$ P(N,k)=P(N-1,k)+\Big(1-P(N-k-1,k)\Big)\left(\frac{1}{2}\right)^{k+1}   $$


I have a cloud function to increment a counter, only if certain fields change within the snapshot ('exercises' in this case).  In my cloud function, I have this check that always fires for some reason:  const before = snapshot.before.data(); const after = snapshot.after.data();      if (before['exercises'] !== after['exercises']) {    console.log(before['exercises']);    console.log(after['exercises']);    // Increment the counter... }   And the log statements are identical:  [ { exerciseId: '-LZ7UD7VR7ydveVxqzjb',     title: 'Barbell Bench Press' } ] // List of exercise objects  [ { exerciseId: '-LZ7UD7VR7ydveVxqzjb',     title: 'Barbell Bench Press' } ] // Same list of exercise objects   What can I do to ensure that these values within the snapshot get treated as equal?  Thank you.

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


Let X and Y be normed spaces and let operators $A,B\in L(X,Y)$ continuously invertible (exists $A^{−1},B^{−1}∈L(X,Y)$). Prove that if  $$\Vert B−A\Vert\leq \frac{1}{2\Vert A^{−1}\Vert},$$ then $$\Vert B^{−1}−A^{−1}\Vert\leq2\Vert A^{−1}\Vert^2\Vert B−A\Vert.$$  I have no idea how to solve this problem, can anyone help me please?


I use MS Office 2010. While using Excel, whenever I type 1 A, 2 A, 3 A up to 12 A and move to next cell by hitting Tab or Enter key it automatically becomes 1:00 AM, 2:00 AM.....12:00 AM. This problem is not there when I type 13 A, it is only up to 12 A.  The same problem is there when I type 1 P, 2 P up to 12 P. It becomes 1:00 PM, 2:00 PM.......12:00 PM. There is no problem for numbers larger than 12.  Why this happens ? How can I stop this ?

This problem is simple to correct but is very very annoying what I'm doing is to type a hour range, eg. (0-1),(1-2),(2-3) so on per cell row     DATE ---   HOUR    1/1/2013  0-1  1/1/2013  1-2 1/1/2013  2-3 1/1/2013  3-4   Excel stupidly keeps formatting 1-2 to a date 2-Jan to make matters worse is when I change it to a number format it gives 41276  I also cannot find the AutoFormat option in excel 2010, I am aware of the Format button in home but there is no autoformat there.


There are those skins representing different countries for some characters, Tracer-Great Britain. How can I obtain them ?

There's brand new skins in overwatch, and they are event themed.  Will they be just gone after the event (those who have it keep it, those who don't are screwed...)  It should be one of 3 scenarios   Skin can still be got in boxes Skin cannot be got in boxes but can be bought with gold Skin is unavailable to any who dont have it, like with the founders skins


I'm a 3dsmax user, I'd like to ask how in Blender, we can "Connect Edges".  Please don't confuse it with loop subdivide ().  I don't mean an entire edge loop. I'd just like to connect select edges. I've attached a simple image explaining it.

Subdivide takes a single face and divides it into quads. I only want to add a single edge to the face off to the side.  Most of the answers I found on the internet recommend using the Knife tool but the knife tool does not cut a single face the way you would think. In fact I have no idea what logic the knife tool uses but it's not at all intuitive: (below gif).  I'm trying to add a single box to the bottom of this desk object to extrude into a drawer box, but I cannot get a face to work with on the bottom of the desk.


Software Center only shows "Editors Pick" and categories nothing else when "All" is selected. Has anyone else seen this?

I've tried the following:   sudo apt install --reinstall ubuntu-software sudo apt update && sudo apt upgrade   Running on Ubuntu 19.04 and tried with Pi-hole disabled.    Thanks


Here's an example  i m trying to run to delete a div element with class "location_description" in iframe but it doesnt work. Any solution?  HTML

     jQuery (end of )  $('#weatherFrame').load(function(){     alert("in");     $("location_description").remove(); });

I would like to manipulate the HTML inside an iframe using jQuery.  I thought I'd be able to do this by setting the context of the jQuery function to be the document of the iframe, something like:  $(function(){ //document ready     $('some selector', frames['nameOfMyIframe'].document).doStuff() });   However this doesn't seem to work. A bit of inspection shows me that the variables in frames['nameOfMyIframe'] are undefined unless I wait a while for the iframe to load. However, when the iframe loads the variables are not accessible (I get permission denied-type errors).  Does anyone know of a work-around to this?


So nowadays we have this beautiful flagging statistics page http://site.stackexchange.com/users/flag-summary/my-user-id.  It has a nice statistics sidebar, for which I propose to make the specifications clickable:    Clicking one of the entries should filter the list of flags accordingly. This can make it easier to track flags deemed important (e.g. custom ones) among the sea of standard "obsolete comment" flags.    NB. I know that this was , but 2011 predates the current flag summary page, so it seemed valid to file a new request.  As to the reason given there (emotions over declined flags and all that), I contend that it will in most cases be beneficial to have someone note their flag has been declined, possibly with a personal moderator message, as this should improve their future flagging behaviour.

I like to know it when I do or see something wrong. So I really like our flagging history (x moderator attention flags, y deemed helpful, z declined, etc.)  I specifically find the declined / disputed flags interesting, because one can learn from his faults. However, now you have to scroll through all your good flags, to see your few bad flags.   Can't we have a function to select only the helpful, only the declined or only the disputed? I also consider  to be a very good idea: sort on flag type ('not an answer', 'spam', etc.) too.


Suppose I have a function $f = xy$. A partial derivative of $f$ with respect to $x$ implies holding $y$ constant:   $$ \frac{\partial f}{\partial x} = y $$  Does this mean that in order to evaluate this derivative, $y$ cannot depend on $x$? For example, if $y = x$ then   $$ \frac{\partial f}{\partial x} = \frac{\partial (x^2)}{\partial x} = 2x $$   Which is inconsistent with the first calculation of $\frac{\partial f}{\partial x}$.  If $y$ indeed cannot depend on $x$, then how does the Lagrangian formalism of classical mechanics make sense? The Lagrangian is a function of $q$ and $\dot{q}$, and when we evaluate $\frac{\partial L}{\partial \dot{q}}$ we 'ignore' all of the $q$ dependence, even though $\dot{q}$ is a function of $q$.

In the calculus of variations, particularly Lagrangian mechanics, people often say we vary the position and the velocity independently. But velocity is the derivative of position, so how can you treat them as independent variables?


What does exactly happen during the interaction of the electromagnetic forces when two objects touch each other?

If you've ever been annoyingly poked by a geek, you might be familiar with the semi-nerdy obnoxious response of      "I'm not actually touching you! The electrons in the atoms of my   skin are just getting really close to yours!"   Expanding on this a little bit, it seems the obnoxious geek is right. After all, consider Zeno's paradox. Every time you try to touch two objects together, you have to get them halfway there, then quarter-way, etc. In other words, there's always a infinitesimal distance in between the two objects.   Atoms don't "touch" each other; even the protons and neutrons in the nucleus of an atom aren't "touching" each other.  So what does it mean for two objects to touch each other?   Are atoms that join to form a molecule "touching"? I suppose the atoms are touching, because their is some overlap, but the subatomic particles are just whizzing around avoiding each other. If this is the case, should "touching" just be defined relative to some context? I.e, if I touch your hand, our hands are touching, but unless you pick up some of my DNA, the molecules in our hands aren't touching? And since the molecules aren't changing, the atoms aren't touching either?  Is there really no such thing as "touching"?


Just wondering what is the purpose of the other file that is created with blender. It takes up the same disk space. Is it ok to delete it? Is it like an autosave file similar to ones Nuke produces?

I teach Blender to classes of game design students in the University of California and a student came to me yesterday with a problem I haven't seen before. She's created a very simple file, but when it's saved Blender puts a .blend1 extension on it every time, not the normal .blend. This means that after it's saved twice there are two .blend1 files in the directory, and no .blend file. I have no idea why this is happening. What has she done? Anyone seen this before?  thanks - Chris


I have trouble to connect my new Nokia 730 to Ubuntu 14.04.  I tried some solution I found searching WEB (like this one: ) but nothing helped. My File-Manager Thunar (I am using XFCE) shows also that something is mounted, but when I click on each icon, following error appears:  In German:     Der Datenträger »Lumia 730 Dual SIM (RM-1040)« konnte nicht eingehängt werden. Fehler beim Initialisieren der Kamera: -1: Unspecified error.   English (automatically translated from askubuntu):     The disk » Lumia 730 Dual SIM (RM -1040 ) " could not be mounted. Failed to initialize the camera : -1: Unspecified error   The Nokia is plugged in but recognized wrongly, as a camera!  With Android I had no problems and the two icons in Thunar pointed respectively to the phone and to the card. The MTP worked with Android and I don't think is a missing MTP tools. I tried and installed all I needed, but with Windows phone does not work correctly.  Can anyone help me and give me a solution?  My Systemlog shows following informations:   kernel: [  461.933996] usb 3-10: new high-speed USB device number 12 using xhci_hcd  kernel: [  461.965116] usb 3-10: New USB device found, idVendor=0421,  idProduct=06fc  kernel: [  461.965125] usb 3-10: New USB device strings: Mfr=1, Product=2, SerialNumber=3  kernel: [  461.965130] usb 3-10: Product: Lumia 730 Dual SIM (RM-1040)  kernel: [  461.965134] usb 3-10: Manufacturer: Microsoft  kernel: [  461.965138] usb 3-10: SerialNumber: 1100000058BE4FB90000000000000000  colord: Device added: sysfs-Microsoft-Lumia_730_Dual_SIM__RM-1040_  colord: Device added: sysfs-(null)

My Nokia Lumia 730 (WP8.1) is not getting detected on Ubuntu 15.04.  Can anybody tell me how to fix this?


Assume you defined the alias alias grep='grep --color=auto' in ~/.bashrc. Then invoking sudo grep wouldn't trigger the alias to be used. Is there a way to do so? If yes, would that solution be applicable to a piped command as well (e.g cat file | grep 'a')?  I'm using bash 4.3.30 on Ubuntu 14.10.

I am running Ubuntu 10.04 and I use upstart for daemon management.  My enterprise application is run as a daemon and must be run as root because of various privileges.  E.g.:  sudo start my-application-long-ID sudo stop my-application-long-ID etc   I would like to introduce an alias to abbreviate these commands as something like:  alias startapp='sudo start my-application-long-ID'   and run it as startapp and that works but I would prefer to not have sudo in the alias.  alias startapp='start my-application-long-ID'   does not when run using sudo startapp, returning sudo: startapp: command not found.  However, when I added the alias:  alias sudo='sudo '  sudo startapp now works but I am still curious why sudo ignores aliases.


Suppose person A has a research project where they need to find a few articles on a particular topic, and write a review of these papers.  Being busy with other coursework, and feeling overwhelmed by the task of searching papers, person A decides to ask person B for help to find a list of articles on the topic. Person B is not a student in the course, but is willing to help person A.  Person A then reads the articles B found and writes their paper on their own.  Has there been plagiarism or other ethical violation committed?  EDIT: An additional concern is whether person A needs to credit person B's work. The goal of the paper would be to develop understanding of the field that the course is about, not specifically train for literature search. The submission will be graded.

Is it unethical to research journals for other students?  For example, a student is researching gifted students and their subsequent ACT/SAT scores.  Then:   Would it be unethical for me to research educational journals and give the student the title of articles that pertain to their research? Would it be unethical for me to charge for this?


I tried to work with timeout decorator(using signal) to timeout a function,But it results in main thread error  Any other solution to timeout a function after some seconds  Thanks

I'm calling a function in Python which I know may stall and force me to restart the script.   How do I call the function or what do I wrap it in so that if it takes longer than 5 seconds the script cancels it and does something else?


Let $G$ be a group generated by $x,y$ with the relations $x^3=y^2=(xy)^2=1$. Then show that the order of $G$ is 6.   My attempt: So writing down the elements of $G$ we have $\{1,x,x^2,y,\}$. Other elements include $\{xy, xy^2, x^2y\}$ it seems I am counting more than $6$. Are some of these equal? how do I prove that?

What is the order of a group $G $ generated by two elements $x$ and $y$ subject only to the relations $x^3 = y^2 = (xy)^2 = 1$? List the subgroups of $G$.  Since the above relation is the 'only' relation, I presume that the order of $x$ is $3$ and the order of $y$ is $ 2$. Also y is the inverse of itself, and xy is the inverse of itself. The inverse of $x$ is $x^2$.  I have calculated the elements of the group manually using the given relation.  $$G = \{1, x, x^2,y, xy, x^2y \}$$  I want to know if there is a formula to calculate the order of $G$? I came across another question where the above relation is $x^3 = y^2 = (xy)^3 = 1$. In this case the group $G has order 12. It is very time consuming to calculate the elements manually. Is there a better way?


Find all positive integers such that $2^n$ divides $3^n-1$.  I tried factoring $3^n-1$ as such: $$3^n-1=(3-1)(3^{n-1}+3^{n-2}+3^{n-3}+\cdots+3+1).$$ But now I'm stuck.

The title says it all. For what natural numbers $n$ does $2^n$ divide $3^n - 1$? By substituting values I can see that this happens for $n = 1, 2, 4$ but are there more? I am not able to prove/disprove.


When i use \usepackage[british]{babel} everything works fine, but when i do \usepackage[spanish]{babel} everything brakes... I reduce the code and find out that the part with scope is the problem, but i can understand why.  \documentclass[12pt]{article} \usepackage[utf8]{inputenc} \usepackage{tabularx,amsmath,graphicx,siunitx,pdfpages} \usepackage[spanish]{babel}  \usepackage[T1]{fontenc}  \usepackage[americanvoltages,fulldiodes,siunitx]{circuitikz} \usepackage{graphicx} \usepackage{letltxmacro} \usepackage{pgfplots} \pgfplotsset{compat=1.8} \usepackage[margin=1in]{geometry}  \usepackage[final]{hyperref}  \usepackage{booktabs,caption,amssymb,commath} \begin{document} \begin{circuitikz}[x=2.5cm,y=2.5cm] \draw   (0,0) to[battery1, l=$V$] (0,2) -- (2,2)   to[R=$R_1$,*-*] (1,1)   to[R=$R_3$, *-*] (2,0) -- (0,0);  \draw    (2,2) to[R=$R_2$, *-*] (3,1)   to[R=$R_4$, *-*] (2,0);  \draw    (1,1) to[R=$R_5$, *-*] (3,1);  \begin{scope}[>=latex,color=magenta,thick,text=black]  \draw[->,rounded corners=7pt]        (0.6,1.9) -- (1.6,1.9) --      (0.7,1) node[anchor=east]{$I_a$} --     (1.6,0.1) -- (0.5,0.1);   \draw[->]    (1.7,1.3)  arc(220:-50:0.4 and 0.15)    node[pos=0.5,above] {$I_b$};   \draw[<-]    (1.7,0.8) arc(-220:50:0.4 and 0.15)     node[midway,above] {$I_c$}; \end{scope} \end{circuitikz}  \end{document}

This code works correctly:  \documentclass{article} \usepackage{tikz} \usetikzlibrary{positioning,calc} \begin{document}  \begin{tikzpicture}   \tikzset{     every picture/.prefix style={       execute at begin picture=\shorthandoff{;}     }   }   \def\names{{"1", "2"}}   \foreach \i in {0,1} {%     \ifnum\i=0\relax       \node (\i) [draw] {\pgfmathparse{\names[\i]}\pgfmathresult};     \else       \pgfmathparse{int(\i-1)}       \node (\i) [draw,right= 1cm of \pgfmathresult]             {\pgfmathparse{\names[\i]}\pgfmathresult};       \draw[dotted] ($(\pgfmathresult.south east) !.5! (\i.south west)$)             -- +(0,1cm);   \fi } \end{tikzpicture} \end{document}   But when I add  \usepackage[utf8]{inputenc} \usepackage[german]{babel}   to the preamble, it starts giving an error:  ! Argument of \language@active@arg" has an extra }. <inserted text>                  \par  l.25 }   the same for russian. It is somehow related to the quotes in the array:   \def\names{{"1", "2"}}   I tried the tricks, shown here for the french, but they don't work.


Why would $\lim_{n \to \infty} {a_n}^{1/n} = \lim_{n \to \infty}(a_{n+1}/a_n)$ be true where $(a_n)$ is a sequence in $\mathbb{R}$?   Edit: Let all $a_n$ be positive.

Today my lecturer put up on the board that:  If $\lim\limits_{n\to\infty}\frac{a_{n+1}}{a_n}$ exists and $a_n>0$ then   $\displaystyle \limsup\limits_{n\to\infty}\left(a_n^{\frac{1}{n}}\right)=\lim_{n\to\infty}\frac{a_{n+1}}{a_n}$  however I am not sure why this is true, can somebody give me a hint or something as to how to go about proving this.  thanks for any help


i want to derive the following expected value formular for $p(x)= N(\mu,\sigma^2)$ (see ):  $$E[X|a<X<b]=\mu+\sigma\frac{\phi(\alpha)-\phi(\beta)}{\Phi(\alpha)-\Phi(\beta)}$$  with $\phi(y):=\frac{1}{\sqrt{2\pi}}e^{-\frac{y^2}{2}}, \Phi(y):=\frac{1+erf(y/\sqrt(2))}{2}$ and  $\alpha:=\frac{a-\mu}{\sigma}, \beta:=\frac{b-\mu}{\sigma}$ .  here's what i got so far: $$E:=\int_a^b xp(x)dx=\int_a^b (x-\mu)p(x)dx+\int_a^b \mu p(x)dx$$  the last integral simplifies to: $$\int_a^b \mu p(x)dx=\mu(\bar\Phi(b)-\bar\Phi(a))$$ with $$\bar\Phi(y):=\frac{1+erf((x-\mu)/\sqrt{2\sigma^2})}{2}$$  for the middle integral i got: $$\int_a^b(x-\mu)\frac{1}{\sqrt{2\pi\sigma^2}}e^{-\frac{(x-\mu)^2}{2\sigma^2}}dx=\frac{\sigma}{\sqrt{2\pi}}\int_{(a-\mu)/\sigma}^{(b-\mu)/\sigma}ze^{-\frac{z^2}{2}}dz=\sigma(-\phi(\beta)+\phi(\alpha))$$  resulting in: $$E=\sigma(-\phi(\beta)+\phi(\alpha))+\mu(\bar\Phi(b)-\bar\Phi(a))$$.  not quite what i was looking for, somebody sees where i did a mistake?

Just wondering if it is possible to find the Expected value of x if it is normally distributed, given that  is below a certain value (for example, below the mean value).


I have the following code:  List<Lead> lList = [select id, email, company from Lead]; Set<String> aSearchSet = new Set<String>();     for (Lead l : lList) {       aSearchSet.add(l.company);     }  Map<String,Account> companyToAccountMap = new Map<String,Account> ([select id, Name from Account where name IN :aSearchSet]);   for (Lead l : lList) {              if (companyToAccountMap.containsKey(l.company)){                  system.debug(LoggingLevel.INFO, l.company + ' exist');              } else {                 system.debug(LoggingLevel.INFO, l.company + ' does not exist');              }              }   It just tells me the Company does not exist  The companyToAccountMap has the following data:   (Account:{Name=My First Company,  Id=001Z00e000evIAG})  (Account:{Name=My Second Company, Id=001Z00e000eIAG})  (Account:{Name=My Third Company,  Id=001Z00w000ePEAG})  (Account:{Name=My First Company,  Id=001Z00s000evIAG})   When i use:  companyToAccountMap.containsKey(inquery.company)   I always get false   And im printing out the inquery.company  And it has 'My First Company', 'My Second Company', ...etc  Does anyone know why?

I'm trying create a Map using a name field as key.  Sample code:  Set<String> priceBooksNames = new Set<String>(); priceBooksNames.add('LN-200'); priceBooksNames.add('LN-100');  Map<string,PriceBook2> priceBooks = new Map<string,PriceBook2>([SELECT name,id FROM PriceBook2 WHERE name=:priceBooksNames ]); system.debug(priceBooks.get('LN-100')); //this is returning NULL   I can see on console that setId on map is not getting the name field value.  VARIABLE_ASSIGNMENT [5]|priceBooks|{"serId":1,"value":{"01sb0000000hiqQAAQ":{"serId":2,"value":{"Name":"LN-100 ADULTOS","Id":"01sb0000000hiqQAAQ"}},"01sb0000000hiqGAAQ":{"serId":3,"value":{"Name":"LN-200 EMPRESAS","Id":"01sb0000000hiqGAAQ"}}}}   What I'm going wrong?


How do you disable the SuperSecretSettings in Minecraft?  I have tried F4, spam clicking, everything.  My version is 1.8. I never knew what it was, and now I can't disable it.

How do I turn off the Minecraft 1.7.2 super secret settings? I tried F3 and F4, hitting Esc repeatedly, all things mentioned on blogs – nothing is working.


Let G be a finite group with no subgroups apart from {1G} and G. (a) Show that G is cyclic. (b) Show that the number of elements in G is either 1 or a prime number.   Any ideas how can I solve the first question?  I was thinking to use Lagrange's theorem stating that the order of G must divide the order of {1G} and G. As G has no other subgroups, the order of G isn't divided by any other number. As the only numbers that have only 2 divisors (1 and itself) are prime numbers, therefore the order of G is a prime number. And we know that if the order of a group is a prime number then the group is cyclic.   Moreover, regarding the second one, is it enough to say that using (a) we know that a group is cyclic if its order is a prime number, therefore the number of elements in G is a prime number.

If $G$ has no proper subgroup, prove that $G$ is cyclic of order $p$, where $p$ is a prime number.     I know that since $G $is a group with no proper subgroups, $g \in G$ is not just the identity. I don't know where to go from there.


Wanted to remove dust from my PC with a canned air aerozol "duster". Tried it a couple of times without applying to my computer and all seemed fine.  Decided to go for the PSU first: since it's a the bottom I tilted the aerozol to the side and it sprayed liquid all over my PSU. (I didn't know that tilting it sprays liquid). Now I .  The liquid seemed to evaporate really fast but I'm still freaking out a little bit before turning it on.  1) What is the amount of time to wait in this situation before it's safe to turn the PC on?  2) What is the worst case scenario from this situation?  3) Any random advice/reassurance?

I'm a little worried. I was using some compressed air cleaner (to be specific, Office Depot® Brand Cleaning Duster) to try to blow the dust off some dusty parts of my computer. The instructions are very explicit about not tilting it at an angle because this could cause the gases to be released in liquid form, but the parts I was trying to clean were at kind of an awkward angle, there was really no good way to get the can in at an upright angle, so some of the liquid did get on the stuff I was trying to clean, unfortunately. It evaporated almost immediately, though.  So now, what should I do? I've seen conflicting information online. Wikipedia says that the liquid form of the gases will act as a solvent, causing unwanted damage to surface coatings, so this is troubling to me, but I don't necessarily trust wikipedia as an accurate source. I have seen it said elsewhere that compressed (canned) air will do absolutely zero damage to your computer, even if you get the refrigerant (the stuff that blows out the nozzle when the can is sideways or upside-down) on your CPU/GPU/RAM/Motherboard.  So, what should I do now? I want to clean the peripherals and such that I used it on off now in the best way possible, to prevent or mitigate any further damage that may or may not have been done or will be done by the liquid. What would be the best method to use now? Just, cloth dampened with water? Isopropyl alcohol? Something else?


Is there a way to add Google Drive to this sidebar not like a shortcut, but pretty much like how OneDrive is? I know there's a Google Drive link in the favorites, but is there a way to expand this like OneDrive has it expanded? Or is that only for the "OneDrive Windows Integration"?  I don't want to just add a shortcut, I want to have the same functionality. The Windows Explorer tweaking tools I've used don't do this.

I want to remove "My PC" and my username from the Windows Explorer sidebar. I just want a bunch of Favorites and the network devices. How do I do this?


It would be nice to have simple image editor when posting something.   This would be particularly useful on sites like "Ask Different" or "Physics" where the person that is answering would like to point something on the image, or screenshot.

More often than not I need to elaborate my question put up on Stack Overflow with a custom sketch, UML class diagram, flow chart.    It is in these times I have to open up a custom paint software, factor out some diagrams, export it as an image, attach it to Stack Overflow. I wouldn't know how complicated it is to invest in having such a sketching or drawing tool integrated, It could even be a basic pen stripped off all the advanced features leaving it a bare minimum.  Such a tool if incorporated into the Stack Overflow "ask question" UI would be certainly helpful.  As of Today this Question has been visited around 170 times and 7 answers, This was meant to be the voice of Stack Overflow users. Would you need a Drawing Tool for you on the Stack Overflow site, would it help you to express you questions and answers better? Sadly, only 2, or 3 answers are in the context of the question. The bounty was meant to be a bait and even that ends tomorrow. Hope you'll get the will and the zest to comment on this question today and in the future .


Will   $(document).ready    in parent page wait for iframe content to be loaded completely?  I have a parent page in which there is a an iFrame. After the iFrame is completely loaded I need to invoke a function in the iFrame from the parent page.

We are using jQuery  to dynamically display an iframe when someone clicks on a picture.  In this iframe, we are using  a javascript library to display multiple pictures.  The problem seems to be that $(document).ready in the iframe seems to be fired too soon and the iframe content isn't even loaded yet, so galleria code is not applied properly on the DOM elements.  $(document).ready seems to use the iframe parent ready state to decide if the iframe is ready.  If we extract the function called by document ready in a separate function and call it after a timeout of 100 ms. It works, but we can't take the chance in production with a slow computer.  $(document).ready(function() { setTimeout(ApplyGalleria, 100); });   My question: which jQuery event should we bind to to be able to execute our code when the dynamic iframe is ready and not just it's a parent?


Let $F=\mathbb{Q}(\sqrt[3]{2}, \sqrt[3]{3})$. Show that over $\mathbb{Q}$ this is an extension of degree 9.  I see that this is equivalent of showing that $\sqrt[3]{2}\notin \mathbb{Q}(\sqrt[3]{3})$. I don't know any other way of showing this except going through $\sqrt[3]{2}=a+b\sqrt[3]{3}+c\sqrt[3]{9}$ which doesn't lead me anywhere.

We all know that $\sqrt[3]{3}\not\in \mathbb{Q}({\sqrt[3]{2}})$ intuitively. We even know that $\sqrt[3]{p}\not\in \mathbb{Q}(\sqrt[3]{q})$ for two distinct primes $p, q$. However, I don't know how to prove these things rigorously. In case of $\sqrt{p}\not\in \mathbb{Q}(\sqrt{q})$, we can just set assume $\sqrt{p}=a+b\sqrt{q}$ for some $a, b\in\mathbb{Q}$ and deduce a contradiction. However, in cubic case, expansion of $(a+b\sqrt[3]{2}+c\sqrt[3]{4})^{3}$ is very complicated and even I expand this I couldn't get any contradiction by this.  To be specific, it gives us 3 diophantine equations  $$a^{3}+2b^{3}+4c^{3}+12abc=3$$ $$a^{2}b+2b^{2}c+2c^{2}a=0$$ $$ab^{2}+2bc^{2}+ca^{2}=0$$  and I don't know how to check solvability of this kind of diophantine equations (over $\mathbb{Q}$). Even if there exists a way to check solvability, I cannot convince that it can be used to prove $\sqrt[3]{p}\not\in \mathbb{Q}(\sqrt[3]{q})$.   So I tried to use Galois theory, but actually I don't know where to go. I assumed $\mathbb{Q}(\sqrt[3]{3})=\mathbb{Q}(\sqrt[3]{2})$ and take a Galois closure, i.e. $K=\mathbb{Q}(\sqrt[3]{3}, w)=\mathbb{Q}(\sqrt[3]{2}, w)$ where $w^{3}=1$ then tried to use field norm maps. We can check that $\beta=\sqrt[3]{3}\cdot\sigma(\sqrt[3]{3})\cdot\sigma^{2}(\sqrt[3]{3})\in \mathbb{Q}$ when $\sigma\in Gal(K/\mathbb{Q}), \sigma(\sqrt[3]{2})=\sqrt[3]{2}, \sigma(w)=w^{2}$. But I cannot get any information from this.   Edit : It would be great if there is a simple algorithm to check whether $\alpha\in K$ or not for a given algebraic number $\alpha$ and a number field $K$.


This a screenshot of . As you can see I am missing the icons for: "Appearance","Online Accounts", "Security & Privacy", and "Time & Date". How can I restore them?  For comparison this is a screenshot of .

I did a fresh install of trusty 14.04, but a lot of icons are missing. I installed from DVD which was painfully slow and I hope to avoid repeating the process, especially since I started customizing stuff.  Here's my settings window:    I've tried:  sudo apt-get install --reinstall gnome-control-center sudo apt-get install --reinstall gnome-settings-daemon-schemas   None of which changed anything.  Any idea? I wanna edit preferences and none of them are in System Settings, neither in Unity Dash.


Is there a way to enter the locked building beside Sans' and Papyrus' house in Snowdin? If yes, how so?

I've been playing a pacifist route in Undertale, and I've noticed that Papyrus's shed seems to be permanently locked with no way to enter it.    I assume that there may be some way to enter it in a Genocide run, but is there any way to enter the shed if I'm playing pacifist?


I have an old computer which currently runs Windows XP. I want to give Ubuntu (v12.10) a try since I heard that it requires less RAM than XP to operate. Here are its specs:  OS: Windows XP RAM: 1GB HDD: 40GB GRAPHICS: ATI Radeon 7000 64MB PROCESSOR: Intel Pentium IV 2.0 Ghz   Can someone give me advice on how to install Ubuntu? I wish to install it on the entire disk with no partitions whatsoever and to permanently delete Windows XP.  Are the specs of my PC enough to smoothly run Ubuntu and at the same time do some basic tasks (document editing, internet browsing, music, videos and some old games)?  Will Ubuntu have the drivers for my hardware?  Thank you very much!

I would like to see a full how-to guide on how to install Ubuntu.


I am learning a chat application in php, I am configuring the project and stuck with the following error  In my it is showing all the code in main.php with the followin error,     Fatal error: Class 'SimpleLoginSystem' not found in C:\xampp\htdocs\chatApp\main.php on   line 14  my index.html is :     <frameset rows="65%,35%" framespacing="1" frameborder="yes" border="1" bordercolor="#FF0000">    <frame src="messages.php" name="main_frame">    <frame src="main.php" name="login_frame" scrolling="no" noresize target="middle"> </frameset>   my main.php is :   <?php  // set error reporting level echo "php ::::::::::::::::::::::::::::::::::"+phpversion(); if (version_compare(phpversion(), "5.3.0", ">=") == 1)  error_reporting(E_ALL & ~E_NOTICE & ~E_DEPRECATED); else  error_reporting(E_ALL & ~E_NOTICE);  require_once('inc/login.inc.php'); require_once('inc/chat.inc.php');  // initialization of login system and generation code $oSimpleLoginSystem = new SimpleLoginSystem();  $oSimpleChat = new SimpleChat();  // draw login box echo $oSimpleLoginSystem->getLoginBox();  // draw chat application $sChatResult = 'Need login before using'; if ($_COOKIE['member_name'] && $_COOKIE['member_pass']) {  if ($oSimpleLoginSystem->check_login($_COOKIE['member_name'], $_COOKIE['member_pass'])) {  $sChatResult = $oSimpleChat->acceptMessages();  } } echo $sChatResult;  ?>   my login.inc.php file is :  <?  // class SimpleLoginSystem class SimpleLoginSystem {  // variables var $aExistedMembers; // Existed members array   // constructor function SimpleLoginSystem() {     $this->aExistedMembers = array(         'User1' => 'd8578edf8458ce06fbc5bb76a58c5ca4',         'User2' => 'd8578edf8458ce06fbc5bb76a58c5ca4',         'User3' => 'd8578edf8458ce06fbc5bb76a58c5ca4'     );     echo "ssss"; }  function getLoginBox() {     ob_start();     require_once('login_form.html');     echo "In login_inc.php";     $sLoginForm = ob_get_clean();      $sLogoutForm = 'logout';      if ((int)$_REQUEST['logout'] == 1) {         if (isset($_COOKIE['member_name']) && isset($_COOKIE['member_pass']))             $this->simple_logout();     }      if ($_REQUEST['username'] && $_REQUEST['password']) {         if ($this->check_login($_REQUEST['username'], MD5($_REQUEST['password']))) {             $this->simple_login($_REQUEST['username'], $_REQUEST['password']);             return 'Hello ' . $_REQUEST['username'] . '! ' . $sLogoutForm;         } else {             return 'Username or Password is incorrect' . $sLoginForm;         }     } else {         if ($_COOKIE['member_name'] && $_COOKIE['member_pass']) {             if ($this->check_login($_COOKIE['member_name'], $_COOKIE['member_pass'])) {                 return 'Hello ' . $_COOKIE['member_name'] . '! ' . $sLogoutForm;             }         }         return $sLoginForm;     } }  function simple_login($sName, $sPass) {     $this->simple_logout();      $sMd5Password = MD5($sPass);      $iCookieTime = time() + 24*60*60*30;     setcookie("member_name", $sName, $iCookieTime, '/');     $_COOKIE['member_name'] = $sName;     setcookie("member_pass", $sMd5Password, $iCookieTime, '/');     $_COOKIE['member_pass'] = $sMd5Password; }  function simple_logout() {     setcookie('member_name', '', time() - 96 * 3600, '/');     setcookie('member_pass', '', time() - 96 * 3600, '/');      unset($_COOKIE['member_name']);     unset($_COOKIE['member_pass']); }  function check_login($sName, $sPass) {     return ($this->aExistedMembers[$sName] == $sPass); } }  ?>   Pls help me... Thanks in advance..

Here's the information :     There are four different pairs of   opening and closing tags which can be   used in PHP. Two of those, <?php ?>   and <script language="php"> </script>,   are always available. The other two   are short tags and ASP style tags, and   can be turned on and off from the   php.ini configuration file. As such,   while some people find short tags and   ASP style tags convenient, they are   less portable, and generally not   recommended.   In my experience most servers do have short tags enabled. Typing  <?=   is far more convenient than typing  <?php echo    The programmers convenience is an important factor, so why are they not recommended?


I have a dedicated server arrangement running  OS Ubuntu 12.04.5 LTS Plesk Onyx   I am migrating to a better server with SSD drives - I have around 40 domains running on my existing server but want to upgrade to the latest stable version of Ubuntu on the new server - is there any problems in making such a big leap in versions? What is the best way to do this?  All help appreciated

I am currently using Ubuntu 10.04. I know there is a 10.10 release, but can I upgrade directly to 11.04? Could you walk me through the steps please?


I try to do a ssh jumphost with a command ssh -J name@server1 name@server2  The answer is unkown option --J I try to reinstall ssh but it does not work. I am on ubuntu 16.04 Anyone has an idea ?

NB: The OpenSSH clients I am using are all at version 7.2, so no  available.  Assume the following setting:   machine foo is a jump host and provides access to host bar via its localhost:10022 bar sits inside a network inside of which we can access host rdp and access its RDP port (3389). I actually give the IP of rdp inside my command lines and configuration, but I presume that it is legit to use its name as long as name lookup works. For brevity I am using rdp here.   The goal is now to gain access to rdp:3389 by connecting to bar via jump host foo and forward that to localhost:33389 on the local machine from which I am invoking ssh bar.  [local:33389] --> {foo} --> {bar} --> [rdp:3389]     Interlude  I have solved this previously with PuTTY as follows:   create a connection to foo and configure a local forwarding -L 33389:localhost:33389, thus tying localhost:33389 on the local machine to localhost:33389 on foo. use the following remote command to carry the port forwarding into the network inside of which bar sits by passing ssh -L 33389:rdp:3389 -A bar. Host bar is configured on foo inside of .ssh/config to connect to localhost:10022 and thereby end up on bar via the jump host.   The PuTTY configuration works like a charm, but it relies on a remote command to be executed. While a shell alias would be one way of going about this, I was wondering if there's a way to keep everything inside the ssh_config(5) used by my client, using ProxyCommand?    A rough equivalent of the above PuTTY configuration is this:  ssh -L 33389:localhost:33389 foo ssh -t -L 33389:rdp:3389 -p 10022 localhost   or, provided that Host bar is configured on foo to go through localhost:10022 of foo:  ssh -L 33389:localhost:33389 foo ssh -t -L 33389:rdp:3389 bar   And this seems to get the job done.  But of course this is plenty to type and it would be neater to be able to put this all into the configuration file and simply type ssh bar on the local machine.  With RemoteCommand as introduced in OpenSSH 7.6 this seems to be rather trivial:  Host bar     HostName foo     RemoteCommand ssh -L 33389:rdp:3389 -A -p 10022 localhost     LocalForward 33389 localhost:33389   ... which should roughly translate to the ssh invocation shown above. But as mentioned before, I am using an older (packaged) version of OpenSSH without support for the RemoteCommand stanza.  Here's the attempt that seems to come closest to what I want to achieve.  Host bar     HostName localhost     Port 10022     ProxyCommand ssh -L 33389:localhost:33389 -W %h:%p foo     LocalForward 33389 rdp:3389   The idea being that on the local machine I will simply invoke ssh bar. In fact it works in that I end up on the shell prompt of bar, but the port forwarding doesn't work at all. While sudo lsof -i|grep 3389 on the local machine gives me:  ssh       15271        accden    6u  IPv6 7933201      0t0  TCP localhost:33389 (LISTEN) ssh       15271        accden    7u  IPv4 7933202      0t0  TCP localhost:33389 (LISTEN)   On the jump host I see nothing listening on any port containing 3389.  Since ProxyCommand establishes the connection to foo and I am giving a LocalForward for the connection to bar, I'd expect this to work.  What am I doing wrong?    Goal is to use ssh bar to connect to bar and at the same time make rdp:3389 available on the local machine as localhost:33389. Tweaking the ssh_config(5) files on the local machine and foo are allowed. Passing remote commands is not a valid answer, though.


Suppose I've added a Cylinder, on the left side there will be the 'add properties' section where I can tinker with all sorts of options such as radius, vertices, Depth etc. I will then resize the Cylinder and once I confirm the resize the 'add properties' section disappears. How can I get back the 'add properties' section back after I've resized?

When you first add a cylinder, you have the option to change the number of vertices, etc, but once you do anything else in blender, it seems you no longer can edit those parameters.   Is there a setting anywhere or an add-on that allows these parameters to be edited later on? If not, how easy would such an addon/feature be to create for anyone reading this?


I know there's tons of libraries out there that does this for you, but I want to know if there's any simple way that's built in.   So far I'm just doing os.system('clear'). This works, but the 'clear' command only inserts a bunch of newlines instead of actually clearing the whole screen.  This is fine for animations that aren't very big, but for animations that cover up more than 1 screen worth of space, it will start scrolling up and down.

Like most Python developers, I typically keep a console window open with the Python interpreter running to test commands, dir() stuff, help() stuff, etc.  Like any console, after a while the visible backlog of past commands and prints gets to be cluttered, and sometimes confusing when re-running the same command several times.  I'm wondering if, and how, to clear the Python interpreter console.  I've heard about doing a system call and either calling cls on Windows or clear on Linux, but I was hoping there was something I could command the interpreter itself to do.  Note: I'm running on Windows, so Ctrl+L doesn't work.


The way cartesian coordinations are presented and used is kinda confusing.  When working with 2D the vertical axis is Y, though when working with 3D the vertical axis is Z and Y becomes the "depth" axis.  Basically I'm thinking the correct way, and best way would be to use the layout of axis.    Though Blender (3D modelling program) and other program, a lot games, present the axis in the "weird order" (my opinion)    Also if you read on Wikipedia about cartesian coordinates, your are presented with that layout of axis.    Is there any specific or logical reason for this "flip" of axis?

I learned at school that the z-axis is up. It is the same in modeling software like Blender. However in many games the y-axis is up.  What is the reason?


My aim is to upload an image and completely replace the original source image with a , as if the custom image sized file was the uploaded image.  For example, I have custom image size wpse, and I want to replace the original image completely with this file upon upload.    How is this possible?   Potential approach could be to hook into the upload process, edit the guid key in the wp_posts table with the URL of the wpse image, then delete the source uploaded file. I'm sure there are other values which needs to be updated.

As our users regularly upload ~6MB images to use on the website (and aren't too familiar with how to resize them first), WordPress stores the originals as well as resizing them to several different sizes.  I'd like a function or plugin that takes the uploaded image, resizes it down to something more manageable and then replaces the original.  I've seen some functions that delete the original but do not replace it, meaning it is impossible to regenerate the thumbnails at a later date. I need this to be replaced so the user can upload a large image and it is automatically resized down and stored for future resizing if needed.


I'm looking for a good book on differential forms with geometrical approach.   Could you kindly recommend some book??   Thanks advance

I'm a looking for a good book to self-study differential forms. Particularly, I'm looking for a book that is as similar as possible to Bert Mendelson's "Introduction to topology" (i.e. a book that procede by  following a: "Definition, theorem, proof" style). In addition, the book that I'm looking for should be as much self consistent as possibile. I'm a first year graduate student in nuclear engineering. My prerequisites are a good understanding of (multivariate and vector) calculus,  linear algebra, and a little of functional analysis, Lebesgue integration theory, PDE. I know nothing about differential geometry, but to my (very) poor understanding  differential forms and concept like manifolds and so on are linked to each other.


As we know that first derivative of the wavefunction is discontinuous when the potential is infinity. Is there any practical potential for which first derivative of wavefunction is continuous?

Is there anything in the physics that enforces the wave function to be $C^2$? Are weak solutions to the Schroedinger equation physical? I am reading the beginning chapters of Griffiths and he doesn't mention anything.


When you start typing @ on the site, it suggests users who commented before you. This feature doesn't exist in the android app. (which is a shame, because commenting is the easiest action you can do on the app)

When commenting, having an autocomplete when you want to @reply to a user would be wonderful (similar to the one available on the desktop site). Normally when I'm on mobile site, I can copy/paste the username, remove the spaces, and I move on with life. But without copy/paste available within the app, the complex or unicode names are nearly impossible to use @reply.


I have a Wired DSL Connection in my laptop, and I want to share this creating a hotspot.  Ubuntu 12.04 Dell Inspiron 1545

I have Ubuntu 12.04 on a HP 430 notebook and this has a single wired internet connection and I would like to share this with a LG Optimus One with Android 2.3.3. I followed  instructions and created a hotspot as shown below, but UbuntuHost is not visible on the LG Optimus One when I enable the Wifi on it.  To summarize, I want my Laptop with an internet connection to act as a WiFi router and access the internet from other devices (LG Optimus One with Android in this case).  What additional steps have to be done?


/dev/disk1 (synthesized):    #:                       TYPE NAME                    SIZE       IDENTIFIER    0:      APFS Container Scheme -                      +250.8 GB   disk1                                  Physical Store disk0s2    1:                APFS Volume Macintosh HD - Data     149.4 GB   disk1s1    2:                APFS Volume Preboot                 79.1 MB    disk1s2    3:                APFS Volume Recovery                527.0 MB   disk1s3      $ mkdir /tmp/recv      $ sudo mount -t apfs /dev/disk1s3 /tmp/recv/      $ ll BaseSystem.dmg     -rw-r--r--@ 1 root  wheel  496664671 Jun 18 15:09 BaseSystem.dmg      $ hdiutil mount BaseSystem.dmg     Checksumming Protective Master Boot Record (MBR : 0)… Protective Master Boot Record (MBR :: verified CRC32 $D80226F2 Checksumming GPT Header (Primary GPT Header : 1)…  GPT Header (Primary GPT Header : 1): verified CRC32 $3488C747 Checksumming GPT Partition Data (Primary GPT Table : 2)… GPT Partition Data (Primary GPT Tabl: verified CRC32 $FB2C82B9 Checksumming  (Apple_Free : 3)…                     (Apple_Free : 3): verified CRC32 $00000000 Checksumming disk image (Apple_HFS : 4)… .............................................................................................................................................           disk image (Apple_HFS : 4): verified CRC32 $E3D25767 Checksumming  (Apple_Free : 5)… ......................................................................................................................................................                     (Apple_Free : 5): verified CRC32 $00000000 Checksumming GPT Partition Data (Backup GPT Table : 6)… GPT Partition Data (Backup GPT Table: verified CRC32 $FB2C82B9 Checksumming GPT Header (Backup GPT Header : 7)…   GPT Header (Backup GPT Header : 7): verified CRC32 $B193AD93 verified CRC32 $C286C93C /dev/disk2              GUID_partition_scheme            /dev/disk2s1            Apple_HFS                       /Volumes/macOS Base System      $ cd /Volumes/macOS\ Base\ System/      $ cd Install\ macOS\ Catalina\ Beta.app/Contents/Resources/      $ sudo ./createinstallmedia --volume /Volumes/test/    /Volumes/macOS Base System/Install macOS Catalina Beta.app does not appear to be a valid OS installer application.   Do I have to download full pack again, even when I just want BaseSystem to boot up?

Does anyone have a Terminal command-line recipe for making a new bootable USB flash drive for one of the new MacBook Air's?  Is there a way to dd copy the USB boot device that comes in the box and make the new copy bootable?  I'd like to make a new backup copy of the USB rescue device for my MBA, preferably on a much larger flash drive with room for a backup of some of my working directories.  Added:  And is it possible to make, not just a rescue drive, but a bootable USB drive that will boot a fully updated version of the OS (say 10.6.8 or later)?  If so how on a MacBook Air 11, and how big a USB stick will this require?


Let's assume I have a text file with a list of dates (dd.mm.yyyy).  01.01.2020 01.03.2020 01.01.2019   How do I sort them out? (oldest to newest in a "from top to bottom" fashion)?

in a file containing :  ... 18-11-2018:othercharacters 10-11-2018:othercharacters 03-10-2018:othercharacters 30-10-2018:othercharacters 27-09-2018:othercharacters 03-12-2018:othercharacters ...   the command :  sort -t- -k2 -k1    does not sort by date, what am I missing ?


I have created virtual box hard disk for Ubuntu 16.04 system. I have dynamically allocated hard disk space of 8GB. After installation, the actual size is only around 3GB. My requirement is, now, I want to reduce 8GB space to 4GB because that is enough space. I need this because, I can create a 4GB image from VDI file and then can write this image to 4GB USB sticks. I am using Virtual Box 5.0.24_Ubuntu r108355 and Ubuntu 16.04.1  Note: I have used VBoxManage command to modify hard disk:   # sudo VBoxManage modifyhd Ubuntu-16-04-1.vdi --resize 4096 /usr/lib/virtualbox/VBoxManage: /usr/local/lib/libldap_r-2.4.so.2: no version information available (required by /usr/lib/x86_64-linux-gnu/libcurl-gnutls.so.4) /usr/lib/virtualbox/VBoxManage: /usr/local/lib/liblber-2.4.so.2: no version information available (required by /usr/lib/x86_64-linux-gnu/libcurl-gnutls.so.4) 0%... Progress state: VBOX_E_NOT_SUPPORTED VBoxManage: error: Resize medium operation for this format is not implemented yet!   Basically I faced this problem :  VBOX_E_NOT_SUPPORTED  VBoxManage: error: Resize medium operation for this format is not implemented yet!  EDIT: I wanted to reduce the Virtual Disk Size, not the VDI file itself. I want to make ISO image from VDI file, and shrinking basically did not help me, it was always 8GB.

My dynamically growing virtual disks (VDI) from various Ubuntu installations in Virtual Box are actually steadily "growing" indeed.  Deleting of files in the virtual machine does not free the space my VDI file took from the host hard disk space.  How do I shrink these files to give the unused hard disk space back to the host?


I want to put 26 x 1.75 tires on my mountain bike.  It currently has 26 x 1.95 tires on it.  Will the rims hold the somewhat smaller tires?

Hi I have original mtn bike tires of 26 x 1.95 on my bike but would like to change to smaller hybrid tires can I use 26 x 1.75 or must I stay with same size. Thanks


I am implementing a server/client program. I need create multiple thread in server to handle message from client. When I compiled the code, there is an error   Exception in thread "Thread-1" java.lang.NullPointerException at server.run(Program.java:59)   Line 59 is   BufferedReader inFromClient = new BufferedReader(new                   InputStreamReader(sSock.getInputStream()));   which is used to read message from client side.  My program code is:     class Program {   public static void main(String[] args) throws UnknownHostException, IOException{       // Program runs as a Server       if(args.length == 2) {       String host = args[0];       int port = Integer.parseInt(args[1]);       String fileName = "serverFile";       ServerSocket sSock = null;        // Open a server socket.       try {          sSock = new ServerSocket(port);       }catch(Exception e) {          System.out.println("Error: cannot open server socket");          System.exit(1); // Handle exceptions.       }        System.out.println("Server is listening on port " + port);        while(true) {          new server(sSock.accept(), fileName).start();       }     }   } }  class server extends Thread {   // Thread t = Thread.currentThread();     Socket sSock = null;    String fileName = null;    server(Socket sScok,String fileName) {    this.sSock = sSock;    this.fileName = fileName;  }   @Override   public void run() {     try {       BufferedReader inFromClient = new BufferedReader(new                       InputStreamReader(sSock.getInputStream()));       PrintWriter sendOut = new PrintWriter(sSock.getOutputStream(),                       true);       String s = inFromClient.readLine();       System.out.println("receive string " + s + "from client");       sendOut.println("send Ack to you");     }catch (IOException e) {       System.out.println("Error: " + e);    }  } }   I have been struggled for a long time...Someone can help would be great.

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