For the definition of the momentum operator $$\hat{P } = -i \hbar \nabla$$ in quantum mechanics, as I understand you can derive this by either considering a more general definition of momentum, i.e. 'canonical momentum' which is an operator and then apply this operator to wave functions. This is shown here in this . We can alternatlively start with translations and use the face that the momentum operator is a generator of translations as is done here in this .   What I am interested in is what is the more fundamental derivation for the position operator: $$\hat{X} = x.$$ To this point I have considered that the motivation for defining position operator is from the definition of the expectation value $$\langle x \rangle = \int dx x |\psi(x)|^2 = \langle \psi|x | \psi \rangle$$ where $| \psi \rangle$ is normalised. Is this the full extent of the motivation or the main point to consider? Is there another motivation for the position operator or is it taken from this motivation and confirmed by experiments to be acceptable?


Should we use 'Title Case' or 'Sentence case' for headlines and buttons?

I am wondering if we should use  or  for buttons and headings in websites and web/mobile apps? Title Case: Manage my Account Delete my Account  Sentence case: Manage my account Delete my account  In  I found the recommendation 'choose your style and be consistent'. This is it? Aren't there any other (additional) recommendations or sources. Like for specific use cases or apps where the one style would be preferred over the other? Edit: The question refers primarily to English, but differences in other languages are also good to know.


How can I bring back the old menu style on Chrome 28 onwards, now that the --disable-new-menu-style switch has been removed?

It used to be that the new, super wide, touch friendly context menu style that Google introduced a few versions of Chrome ago could be turned off using the start up flag "--disable-new-menu-style".  As of Chrome 28, this is no longer the case, and as a desktop user it is very irritating to see menus that previously fit in the screen not to do so anymore — I don't think I can get used to it. Is there any way around it? If the flag is gone for good, can the style of the context menus be perhaps edited with custom css like the web inspector?


Is a human (or other) electrical signal absolutely necessary to activate a capacitive touchscreen?

I know this is the general wisdom, and that someone has asked a similar question here:   However, I didn't quite understand the conclusion that by simply grounding e.g. A carrot or stylus, or connecting them to a conductive plate, this would be enough to allow them to activate the touchscreen. Is the idea that the ground or conductive plate pick up enough electricity in the environment that they can act as a substitute for a human?   As a related note, I held a stylus through many layers of folded up, thick woollen sweater, and it was still able to activate the touchscreen. Was my body's electrical signal definitely conducted through the sweater?   Apologies if my question sounds a bit ignorant. I am not an electrician, but I understand the basics of electrical circuitry and how capacitors work. The iPhone's capacitive touchscreen nevertheless seems like a bit of a black box to me.    Thank you all. Based on your responses and my reading of the Q&A referenced by @gbarry, my understanding of this is now almost complete. There remainas these issues that I am unclear on:   It seems that it is a very common misconception, then, that it is a body's electrical signal (current) that is necessary to activate the iPhone touchscren in particular. Rather, what is sensed by the electrodes of the touchscreen circuit is either insulation or capacitive coupling, but supposedly not conductivity. Since I always considered insulation and conductivity as belonging on the same scale, could someone perhaps clear this up for me, while illuminating whether or not this is what is meant here by "capacitive coupling"?  I have understood that large surface area is often an important determinant of capacitive coupling. Is this the only reason that it is suggested the contacting body be grounded, or is it necessary for another reason, e.g., To "complete the circuit" initiated by the iPhone?    I'll gladly award the bounty to whomever can answer these questions in a way that I can understand! Thank you again.


Session_ID_Remove Issue in API callouts in Salesforce

I have below code to get session id of another org and to connect it. Problem I am facing is not able to see session id .  HttpRequest request = new HttpRequest();         request.setEndpoint('https://' + LOGIN_DOMAIN + '.salesforce.com/services/Soap/u/22.0');         request.setMethod('POST');         request.setHeader('Content-Type', 'text/xml;charset=UTF-8');         request.setHeader('SOAPAction', '""');         request.setBody('<Envelope xmlns="http://schemas.xmlsoap.org/soap/envelope/"><Header/><Body><login xmlns="urn:partner.soap.sforce.com"><username>' + USERNAME + '</username><password>' + PASSWORD + '</password></login></Body></Envelope>');         Dom.XmlNode resultElmt = (new Http()).send(request).getBodyDocument().getRootElement()             .getChildElement('Body','http://schemas.xmlsoap.org/soap/envelope/')             .getChildElement('loginResponse','urn:partner.soap.sforce.com')             .getChildElement('result','urn:partner.soap.sforce.com');          //----------------------------------------------------------------------         // Grab session id and server url (ie the session)         //----------------------------------------------------------------------         final String SERVER_URL = resultElmt.getChildElement('serverUrl','urn:partner.soap.sforce.com').getText().split('/services')[0];          System.debug('SERVER_URL ->'+ SERVER_URL);         final String SESSION_ID = resultElmt.getChildElement('sessionId','urn:partner.soap.sforce.com').getText();          //----------------------------------------------------------------------         // Load first 10 accounts via REST API         //----------------------------------------------------------------------         final PageReference theUrl = new PageReference('https://xxx/services/apexrest/restCreateTaskForTrainings');         theUrl.getParameters().put('vEmail','abc@xyz.com');         theUrl.getParameters().put('vSubject','Test Task Creation');         theUrl.getParameters().put('vDate','01/01/2018');         request = new HttpRequest();        System.debug('URL Clled :' + theUrl.getUrl());         request.setEndpoint(theUrl.getUrl());         request.setMethod('POST');         request.setHeader('Authorization', 'OAuth ' + SESSION_ID);           HttpResponse res = h.send(request);   I am getting this issue from today onwards.Any help would be appreciated.


Is it possible to obtain a transit visa at Heathrow Airport?

I am an Iranian national travelling with British Airways from Tehran, Iran via Heathrow Airport, London to Shanghai, China. I will arrive at LHR on 28th at 11:55am and depart at 14:10pm without changing terminals.  If I need a transit visa, can I obtain one at Heathrow Airport?   I am scared that British Airways have stopped a few people from boarding flights.  Also, do I need a transit visa to enter the UK?  I want to do some sightseeing.  What are the chances of getting past officials using transit without visa concession?


I want to get the name of the variable in a list with the index. For example:   a = 1   b = 2 list = [a, b] print(list[0])   and the output is 1 Is there a way to get "a" as a String instead of 1?  Also, the above code is just an example. I am coding in pygame, so the actual type of values of the variables in the list is Surface, not int.  Thank you for helping


I have a Dictionary<string,List<object>> and i want iterate though it and want to bind the list values on cshtml page.And i am getting the values as :    This is my cshtml page where  i am looping though Dictionary<string,List<object>>

         @foreach (var PriceList in Model.ProductPriceDicList)         {

@PriceList.Key

                  @foreach (var DicPriceList in Model.ProductPriceDicList.Values)                   {

                                                                              @DicPriceList[Convert.ToInt32(PriceList.Key)].SubProductName                                     	                                          @DicPriceList[Convert.ToInt32(PriceList.Key)].ProductCost

                   }

         }
   my question is how to iterate through the dictionary, where i can get header as Key and value as List of object. Thanku


limit and infinite ordinals: same thing?

I'd like to clarify my understanding re:  limit and infinite ordinals.   says:  An initial infinite ordinal is a limit ordinal.    Is it true the other way around?  That is  if I have a limit ordinal must that also be an infinite initial ordinal?  This would seem to be true because for a limit ordinal x, if I have any 'y' less than x, then I have a 'w' such that   y < w < x.       And the definition of infinite initial ordinal 'x' is:  For all B < x,  we also have B dominated by (of lesser cardinality than) x.  I understand that this means there is no way to have an onto map from B to x.   If x is a limit ordinal, then for all y < x, there is no way to make an onto map from y to x.  This is true because for whatever supposedly onto function f from B to x you give me, I can always take each image of f (in x), and double that image to produce an ordinal in x which is not mapped to by f.  Does this make sense ?  Thanks in advance for confirming! (or showing false, perhaps with a counter-example?)


Find all differentiable functions $f$ such that $f(f(x))=f'(x)$

Here is a problem I made up:  Find all differentiable functions $f$ from the reals to the reals such that $f(f(x))=f'(x)$ for all real $x$.


To show a particular element is the unit of a ring

$Problem$  Suppose that a and b belong to a commutative ring $R$ with unity. If $a$ is the unit of $R$ and $b^2 = 0$; Show that $a+b$ is a unit of $R$.  $ Attempt$  $(a+b)(a-b) a^{-2}= (a^2-b^2)a^{-2}= 1$.   How to show that $a+b$ is a unit if we replace $b^2$ with $b^n$  I have just started ring theory after finishing Group theory.  Any hint or suggestion will be appreciated.


Why are relays used in circuits when we have transistors?

Why do I find relays being used right next to transistors? What is the benefit or use of using a relay over a transistor switch?


How to find where an input occurs within a list in python?

I'm building a simple hangman game right now, and I want to be able to identify where in a list a user guesses a specific letter. For example, if the word list was [D,R,A,G,O,N] -- and the user guesses A, I want to be able to get a return that would say 4...this is my failed code so far  import random  word_list = ['red', 'better', 'white', 'orange', 'time'] hidden_list = [] selected_word = random.choice(word_list) letters = len(selected_word) selected_word_list = list(selected_word) game_playing = True  print('My word has ' + str(letters) + ' letter(s).')  print(selected_word_list)  for i in selected_word_list:     hidden_list.append('_')  while game_playing:     print(hidden_list)     guess = input('What letter do you want to guess?')     if guess in selected_word_list:         print('Nice guess!')     else:         print('Nope!')


I am using ubuntu 18.04.I got this error when i try to upgrade

Get:1 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 gnome-software-common all 3.28.1-0ubuntu4.18.04.1 [2,482 kB] Err:1 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 gnome-software-common all 3.28.1-0ubuntu4.18.04.1   Hash Sum mismatch   Hashes of expected file:    - SHA256:20e50c1116271b6c38526a5d78e78c51b86bc48c7c03d0005ebe06a3e3fb23de    - SHA1:01c39d0c31ccafba417891022bd61e6c32ae72a3 [weak]    - MD5Sum:4e0888a7d1cf9a766599c554287910c1 [weak]    - Filesize:2481700 [weak]   Hashes of received file:    - SHA256:af6b6c41ed8389b2aa5f672ede2c845baa5aa1eaeacec9de6ac34fac3fa53416    - SHA1:2a769e00e6d76749e0f2b3d54975efa7d6b60701 [weak]    - MD5Sum:6bfd90cbe01b7c3e5f666860f5bd73b2 [weak]    - Filesize:2481700 [weak]   Last modification reported: Thu, 17 May 2018 11:30:45 +0000 Get:2 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 ubuntu-report amd64 1.2.0~bionic [1,694 kB] Err:2 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 ubuntu-report amd64 1.2.0~bionic   Hash Sum mismatch   Hashes of expected file:    - SHA256:410b0572c1b66af9648c01bf66804c09986f00ed0843cf459a9d282c8d06402d    - SHA1:e731d01aa7370cf5a8882949c04c081816792db9 [weak]    - MD5Sum:153fa99051248ebfe7880ab9e04cc307 [weak]    - Filesize:1693624 [weak]   Hashes of received file:    - SHA256:c7df99a8fdc7812a29ed79900c32fab6b371821f17e6463acbee9ac0f8684df5    - SHA1:a57af71ecd4813d1a9190105d314248eac43f5b7 [weak]    - MD5Sum:3fb8028c3be9b1411cf21ceefef78d0d [weak]    - Filesize:1693624 [weak]   Last modification reported: Tue, 03 Jul 2018 07:03:24 +0000 Fetched 4,175 kB in 6s (708 kB/s)           E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/main/g/gnome-software/gnome-software-common_3.28.1-0ubuntu4.18.04.1_all.deb  Hash Sum mismatch    Hashes of expected file:     - SHA256:20e50c1116271b6c38526a5d78e78c51b86bc48c7c03d0005ebe06a3e3fb23de     - SHA1:01c39d0c31ccafba417891022bd61e6c32ae72a3 [weak]     - MD5Sum:4e0888a7d1cf9a766599c554287910c1 [weak]     - Filesize:2481700 [weak]    Hashes of received file:     - SHA256:af6b6c41ed8389b2aa5f672ede2c845baa5aa1eaeacec9de6ac34fac3fa53416     - SHA1:2a769e00e6d76749e0f2b3d54975efa7d6b60701 [weak]     - MD5Sum:6bfd90cbe01b7c3e5f666860f5bd73b2 [weak]     - Filesize:2481700 [weak]    Last modification reported: Thu, 17 May 2018 11:30:45 +0000 E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/main/u/ubuntu-report/ubuntu-report_1.2.0~bionic_amd64.deb  Hash Sum mismatch    Hashes of expected file:     - SHA256:410b0572c1b66af9648c01bf66804c09986f00ed0843cf459a9d282c8d06402d     - SHA1:e731d01aa7370cf5a8882949c04c081816792db9 [weak]     - MD5Sum:153fa99051248ebfe7880ab9e04cc307 [weak]     - Filesize:1693624 [weak]    Hashes of received file:     - SHA256:c7df99a8fdc7812a29ed79900c32fab6b371821f17e6463acbee9ac0f8684df5     - SHA1:a57af71ecd4813d1a9190105d314248eac43f5b7 [weak]     - MD5Sum:3fb8028c3be9b1411cf21ceefef78d0d [weak]     - Filesize:1693624 [weak]    Last modification reported: Tue, 03 Jul 2018 07:03:24 +0000 E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?


Infinite probability of natural numbers.

Two natural numbers $x$ and $y$ are selected at random. Find the probability that $x^2 + y^2$ is divisible by $10$.  I have no clue how to do this.


Removing disadvantage from being Small and wielding a Heavy weapon

I rolled a Hexblade Warlock for a campaign I am playing, with the Pact of the Blade and Cursebringer invocation.   What I did not account for is that because I am playing a Halfling, I have disadvantage with my weapon (a silver greatsword).  Is any way to remove disadvantage  due to being Small and wielding a Heavy weapon without multiclassing? If its only possible with multiclassing, what is the smallest number of levels required?  I was thinking about a spell that increases my size like the enlarge reduce, but that is a second level spell for sorcerers and wizard only.  I am looking for specific items/spells that a warlock could use to counter this disadvantage that i could use consistently, so not a potion or something.


iam unable to format it not use it. i need an app that will help me recover my data please anyone can share light to this. Thanks in anticipation


My desktop PC doesn't have wifi as it's pretty old, but my laptop has internet access through wifi.   How can I connect my desktop PC to the internet using a lan/ethernet cable? My laptop runs Ubuntu and my PC runs Windows  I tried several methods from other similar questions, but none worked. When I click on the shared connection it says      (0) Active connection could be attached to the device.    OR it sometimes says      (2) active connection removed before it was initialized


Python - How do I shorten a float when I print it?

I was doing an exercise of my python class and after seeing the results i was imagining what could i do to shorten the resultant variable (to avoid results like: 3.888888888, and transform it to 3.8 or 3.88. Someone could help me?! (Also the code is working very well i just wanna improve it) OBS: My code is at my native language, so ill explain. The user type a number and it will show your double, triple, square root (b,c and d; respectively) a = float(input("Digite um número para descobrir: \n\nSeu Dobro \nSeu Triplo \nSua Raiz Quadrada \n\nDigite um número: ")) b = a * 2 c = a * 3 import math d = math.sqrt(a) print() print("RESULTADOS: \n\nDobro: {} \nTriplo: {} \nRaiz Quadrada: {} \n".format(b, c, d))


I have the basic idea of how to work out the integral of a trig function, but am having trouble in applying the concept. Would really appreciate it if someone could help me. Thanks!


Does having CWM mean bootloader is unlocked?

I flashed CWM using Rom Manager. Does this mean that my Galaxy S4 bootloader is unlocked?  I'm using Samsung Galaxy S4 (SGH-I337M) (Canadian Telus)


In LaTeX align, I'm struggling to align polynomial terms and assume there's an easy way to do it. But I cannot find the simple/elegant solution. What I would like is something like this:  x1 + x2 ______________ = 3  x1_______________+ x3  = 4  etc with more lines and variables (the underlines are just for space/alignment). Any help appreciated.  UPDATE Here is the solution I found:  \begin{alignat*}{7} 8x_1 &{}+ 4x_2 &{}+ y_1   &        &        &        &= 160     \\ 4x_1 &{}+ 6x_2 &          &{}+ y_2 &        &        &= 120     \\ x_1  &         &          &        &{}+ y_3 &        &= 34      \\ \phantom{{}+{}x_1}&{}+x_2&&        &        &{}+ y_4 &= 14      \\ x_1\geq0&x_2\geq0&y_1\geq0&y_2\geq0&y_3\geq0& y_4\geq0 \end{alignat*}   with result:


Permissions for new files in shared directory

We just got a new iMac are using the /Users/Shared directory to store media assets (pictures, audio, video) that we want accessible to all users on the machine. After copying over all the files initially, we set the desired permissions and then applied the same permissions to all directory contents recursively. This is working fine, except then whenever someone creates a new file or directory, it does not have the same permissions and we have to repeat the whole permissions process before everyone can access it.  Is there a way that we can set permissions for all new files/directories created within that directory?


Deleting features with identical table attributes in QGIS

How do I delete features with identical table attributes in QGIS? Otherwise, is there a tool like the 'Delete Identical Tool' in ArcGIS? For example, if I had 4 rows, and 3 columns, where I wanted to delete identical features based on 2 columns:     id value 1 value 2     1 A m   2 A m   3 A p   4 B m     I want it to be reduced to only 1 feature for each identical set of attributes:     id value 1 value 2     1 A m   3 A p   4 B m     In ArcGIS Desktop, this is a simple tool shown below called 'Delete Identical', where I can select one or more columns at the same time. I use this tool all the time, am switching to QGIS.


Can I carry a watch as a gift in my carry-on luggage when flying from Kolkata to Chennai?

I bought a new watch for my friend and made a surprise gift pack as well. The watch is an expensive one. I am flying from Kolkata to Chennai and my friend will take it from Chennai and will fly to Bangalore next.    Can I take this watch and surprise gift box in my carry-on luggage?    Is extra tax or custom search needed?


i am using ubuntu 12.04lts i try to inslall php5 it create an error  "1.Could not open lock file /var/lib/dpkg/lock - open (13: Permission denied)    2.Unable to lock the administration directory (/var/lib/dpkg/), are you root?"


Why is the sky of the moon always dark compared to the sky of the earth, doesn't it have day and night like earth?


How to center my figure without the limitation of text width?

\begin{figure}[h!]     \centering     \includegraphics[width=18cm]{3DQN.eps}     \caption{Performance and instability}     \label{3DQN} \end{figure}  I'm writing with the LNCS template on Overleaf, and there's a rather wide figure I need to put on (illegible if made narrower). Because the left side is be lined up with the text, the \centering command doesn't work anymore, and it turns out to look like the following:  Is there a way to break the left-lineup and center the figure without changing its width (like where the yellow box is)? Thank you!


(Anti-)commutation relations of fermions in GUT

Suppose we found a great unification group (like SU(5)) and wrote a Lagrangian with all the known particles/fields (quarks, electrons, neutrinos...) with such symmetry. How would commutation rules be imposed? Would I have commutation or anti-commutation rules between different fermions? In other words, which of the following two is true: $ [\psi_{electron}, \psi_{quark}] = 0$ or $ \{\psi_{electron}, \psi_{quark} \}= 0$?


What's the difference in meanings between tactical and strategic?  My teacher told me tactical is short term whereas strategy is related with long time ambitions. But I think otherwise that both are synonyms. Please help me out in context of geopolitics.


Javascript file not working on github pages

I am able to load my javascript file on the local machine. But on github pages, it is not working.  I have included the file in index.html as   <script src="script.js" type="text/JavaScript"/>   The website is   The code is at   Any help would be appreciated. Thanks in advance.  Edit 1 I tried to add the following code in my javascript file to check if its working, but it is not working on github page and working locally.  $(document).ready(function(){     alert("hi");}


How can I multiply a column by a variable and write out?

I would like to multiply a single column in a .txt file by a variable and then write to another .txt file. What am I missing from the awk line? Appreciate any help in advance.  !/bin/bash  FILES=/path/to/files for f in ${FILES} do     echo $f     wc -l $f     B=10000000     TOTALLINES="$(wc -l $f | cut -f1 -d' ')"     echo "TOTALLINES: ${TOTALLINES}"     SCALINGFACTOR=$(echo "100000000 / $TOTALLINES" | bc -l)     echo "scaling_factor:  ${SCALINGFACTOR}"     awk '{printf($1"\t"$2"\t"$3"\t"$4 * "${SCALINGFACTOR}")}' $f"_prepped.txt" > $f"_normalized.txt"  done


Numbered tag \begin{align} math equation

First of all, my previous question was closed bcz it was considered as a duplicate.  But it is not.  I've checked for duplicate links and the link is irrelevant because it only discusses image numbering. So, i'll ask again for the same topic. I want the numbered tag on \begin{align} based on the section. So, for example if i have section 2.3 (2.3 means Chapter 2 and Section 3) my tag must be automatically 2.3.1, 2.3.2,, and so on. Can you help me? Thanks in advance My MWE: \documentclass{book} \usepackage{blindtext} \usepackage{amsmath}  \begin{document} \chapter{One} \section{one} \blindtext \chapter{Two} \section{one} \blindtext \section{two} \blindtext \section{three} \begin{align} c = \sqrt{a^2 + b^2} \end{align} \end{document}  To be clear the result of my equation should be:


Neural Network for Rain Prediction - Only Learning Averages

I'm attempting to create a Neural Network to use as a rain model to generate representative precipitation levels for a given location.  The problem I'm facing is that the network always converges to the average amount of rain. For example, the trained network predicts that it will be constantly raining a small amount all the time, instead of predicting that at some times it will be raining and sometimes it won't.  Convergence on average through training: (green - actual, blue - predicted)   Is it reasonable to expect a neural network to be able to predict like this? If so, what can be done to allow the network to learn in this way?  (I'm using DL4J, one hidden layer with 5 nodes, squared loss function, month and hour as inputs (normalised))    MultiLayerConfiguration modelConfiguration = new NeuralNetConfiguration.Builder()     .seed(seed)     .iterations(1)     .optimizationAlgo(OptimizationAlgorithm.STOCHASTIC_GRADIENT_DESCENT)     .learningRate(0.0001)     .updater(Updater.NESTEROVS)     .list()     .layer(0, new DenseLayer.Builder()         .nIn(4)         .nOut(5)         .weightInit(WeightInit.XAVIER)         .activation(Activation.LEAKYRELU)         .build())     .layer(1, new OutputLayer.Builder(LossFunctions.LossFunction.SQUARED_LOSS)         .weightInit(WeightInit.XAVIER)         .activation(Activation.IDENTITY)         .nIn(5)         .nOut(1)         .build())     .pretrain(false)     .backprop(true)     .build();


Problem  Compute $$\displaystyle \int_0^\infty \frac{dx}{1+x^3}.$$  Solution  I do partial fractions $$\frac{1}{x^3+1}= \frac{2-x}{3 \left( x^{2}-x+1 \right)}+\frac{1}{3 \left( x+1 \right)}.$$  But we could simplify the left one $$\frac{2-x}{3\left( x^{2}-x+1 \right)} = \frac{2}{3}\cdot \frac{1}{x^{2}-x+1}-\frac{x}{x^{2}-x+1}$$            From here, I do this .  But I find the wrong primitive functions. Why am I wrong, and how do I find the correct one?


Updating DE through SmartCapture in CloudPage

Consider a scenario where a mail will be sent to contacts in Data Extension. The mail contains a button that will redirect to CloudPage.   This cloud page has a smart capture that will prepopulate some fields like EmpId, FirstName, LastName in text fields from contacts in DE and there are Other input fields where the user will enter Data to input fields and click the submit button.   After hitting the submit button the cloud page, Contact in DE gets updated by adding newly entered data by the user.  My problem in this scenario is how to update the contact in DE. smart capture is unable to update because it is trying to add the record in DE but EmpId(Primary Key) already exists in DE.


latex gives me the error: Ouch---my internal constants have been clobbered

As the title states, compiling with latex produces the error, right away:  Ouch---my internal constants have been clobbered!---case 14   I have no idea what this means... I use TexLive 2012. I updated my texmf.cnf and ran fmtutil-sys and texhash. I guess texhash may have messed it up?  Any ideas?  As requested a minimal working example:  \documentclass{article} \begin{document}     Any tex file. \end{document}


Show that infinitely many members of $1,11,111,1111,\dots$ are divisible by $2^{2017}+1$.    I know that the sequence above is equal to $a_n = \frac{10^n-1}{9}$ for $n = 1,2,3,\dots$. I also feel that I should use the pigeonhole principle but do not know how to attack the problem.


Why is there not a simpler way to calculate the standard deviation?

Steps of getting standard deviation. :        Work out the average (mean value) of your set of numbers   Work out the difference between each number and the mean   Square the differences   Add up the square of all the differences   Divide this by one less than the number of numbers in your set -   this is called the variance   Take the square root of the variance and you've got the standard   deviation      Am I missing out something, or why do we need to square the differences in step 3?  Why not simply do a Abs (multiply all negative numbers by -1) in step 3?  Also, my second question is why do we need to divide by one less than the number of numbers in the set in step 5? why not simply divide by the number of numbers?


Bad signature on verifying the 18.04.5 sha256 checksum

I was following the "" tutorial to verify the ubuntu-18.04.5-desktop-amd64.iso download. After the following command gpg --keyid-format long --verify SHA256SUMS.gpg SHA256SUMS  I receive the following message: gpg: Signature made Thu 13 avg 2020 17:02:20 CEST  gpg:                using RSA key 843938DF228D22F7B3742BC0D94AA3F0EFE21092  gpg: BAD signature from "Ubuntu CD Image Automatic Signing Key (2012) <cdimage@ubuntu.com>" [unknown]  I've downloaded all the files (SHA256SUMS.gpg, SHA256SUMS, iso file) from the  page. I've been told that there is a similar question answered . I acknowledge this. But (1) the question is rather old, maybe in the meantime the files SHA256SUMS and SHA256SUMS.gpg have changed and (2) the answers in that question do not answer my problem. I have downloaded the files with Save Link As... from Firefox browser. It would help me if I get confirmation that the files are ok; then the problem is on my side. Then any help what the problem might be would be useful. Edit: it seems . So there may be something wrong with the signature.


Closed form for CRT solution using Euler $\phi\,$ (totient)

Can anyone show some hints to this? If $\gcd(a,b)=1$, then $a^{\phi(b)}+b^{\phi(a)}=1 \pmod{ab}$. I know that $a^{\phi(b)}=1 \pmod{b}$, and similarly, $b^{\phi(a)}=1 \pmod{a}$, but then how do I combine the work so that I get the result I need? Thanks!


Help proving inequality $\alpha^\alpha\left(1 - \alpha \right)^{1-\alpha} \geq \beta^\alpha \left(1 - \beta\right)^{1-\alpha}$

So I got a request from a friend to try and solve this, but I've stuck.  $$\alpha^\alpha\left(1 - \alpha \right)^{1-\alpha} \geq \beta^\alpha \left(1 - \beta\right)^{1-\alpha}$$  for $\alpha, \beta \in (0,1)$.  I have reached here:  $$\left(\frac{\alpha}{\beta}\right)^\alpha\geq\left(\frac{1-\beta}{1-\alpha}\right)^{1-\alpha}$$  but maybe I have to use a theorem or an already proven inequality that I can't seem to come up to. I thought trying first $0\lt\alpha\lt\beta\lt1$ and then $0\lt\beta\lt\alpha\lt1$ but can't find my way through.


I'm getting linker errors when trying to compile a templated class.  I'm not too hot on C++ templated programming and the workings of the compiler (MSBuild/VS2012) and am having difficulty in determining what I've done wrong.  I'm compiling with /CLR and I get a series of linker errors (LNK2005) when I try to compile my source files, which approximate to:  ISaveStrategy.h:  #pragma once #pragma unmanaged  template<class T> class ISaveStrategy { public:     enum SaveResult {OK, Error};       virtual SaveResult Save(const T&  itemToSave) = 0; };   SaveToXmlStrategy.h:  #pragma once  #include <gcroot.h> #include "ISaveStrategy.h"  #pragma unmanaged  namespace System{namespace Xml{ref class XmlWriter;}}  template<class T> class SaveToXmlStrategy : public ISaveStrategy<T> { public:      SaveToXmlStrategy(gcroot<System::Xml::XmlWriter^> writer)         : m_writer(writer)     {}      virtual SaveResult Save(const T& itemToSave);  private:     gcroot<System::Xml::XmlWriter^> m_writer; };   SaveToXmlStrategy.cpp:  #pragma once  #include "stdafx.h" #include "SaveToXmlStrategy.h" #include "IKeyFrame.h" #include "IKeyFrameTransition.h" #include "ICueProvider.h"  #pragma managed  using namespace System; using namespace System::Text;  template class SaveToXmlStrategy<IKeyFrameTransition>; SaveToXmlStrategy<IKeyFrameTransition>::SaveResult SaveToXmlStrategy<IKeyFrameTransition>::Save(const IKeyFrameTransition& keyFrame) {     return SaveResult::OK; }   template class SaveToXmlStrategy<ICueProvider>; SaveToXmlStrategy<ICueProvider>::SaveResult SaveToXmlStrategy<ICueProvider>::Save(const ICueProvider& keyFrame) {     return SaveResult::OK; }   template class SaveToXmlStrategy<IKeyFrame>; SaveToXmlStrategy<IKeyFrame>::SaveResult SaveToXmlStrategy<IKeyFrame>::Save(const IKeyFrame& keyFrame) {     SaveResult result = SaveResult::OK;     return result; }   Implementation.cpp:  #pragma once #include "SaveToXmlStrategy.cpp"  //inside a function body : ISaveStrategy<IKeyFrame>& keyFrameSaver = SaveToXmlStrategy<IKeyFrame>(xmlWriter.get());


Downloaded latest version from   Working with Ubuntu 14.04.2 LTS (x86_64)  Tried to configure it without success:  alex@pc:~/Downloads/openvrml-0.18.9$ ./configure ... checking for boost_thread-mt library... no configure: error: in `/home/alex/Downloads/openvrml-0.18.9': configure: error: libboost_thread-mt not found See `config.log' for more details   Libraries seem to be properly installed:  alex@pc:~$ ls -l /usr/lib/x86_64-linux-gnu | grep -E "boost_thread|boost_filesystem|boost_system" -rw-r--r--  1 root root   217692 ene 16  2014 libboost_filesystem.a lrwxrwxrwx  1 root root       29 ene 16  2014 libboost_filesystem.so -> libboost_filesystem.so.1.55.0 -rw-r--r--  1 root root    88936 jun 21  2014 libboost_filesystem.so.1.54.0 -rw-r--r--  1 root root    88936 ene 16  2014 libboost_filesystem.so.1.55.0 -rw-r--r--  1 root root    49186 ene 16  2014 libboost_system.a lrwxrwxrwx  1 root root       25 ene 16  2014 libboost_system.so -> libboost_system.so.1.55.0 -rw-r--r--  1 root root    14536 jun 21  2014 libboost_system.so.1.54.0 -rw-r--r--  1 root root    14536 ene 16  2014 libboost_system.so.1.55.0 -rw-r--r--  1 root root   200894 ene 16  2014 libboost_thread.a lrwxrwxrwx  1 root root       25 ene 16  2014 libboost_thread.so -> libboost_thread.so.1.55.0 -rw-r--r--  1 root root    88632 jun 21  2014 libboost_thread.so.1.54.0 -rw-r--r--  1 root root    92728 ene 16  2014 libboost_thread.so.1.55.0 alex@pc:~$   Header files seem to be installed too:  alex@pc:~$ ls -l /usr/include/boost/thread.hpp  -rw-r--r-- 1 root root 839 ene 16  2014 /usr/include/boost/thread.hpp alex@pc:~$


To find limit of $\lim_{x\to 0}\frac {\cos(\sin x) - \cos x}{x^4} $. I differentiated it using L Hospital's rule. I got $$\frac{-\sin(\sin x)\cos x + \sin x}{4x^3}\text{.}$$ I divided and multiplied by $\sin x$. Since $\lim_{x\to 0}\frac{\sin x}{x} = 1$, thus I got $\frac{1-\cos x}{4x^2}$.On applying standard limits, I get answer $\frac18$. But correct answer is $\frac16$. Please help.


Calculating Fisher Information for Bernoulli rv

Let $X_1,...,X_n$ be Bernoulli distributed with unknown parameter $p$.   My objective is to calculate the information contained in the first observation of the sample.  I know that the pdf of $X$ is given by $$f(x\mid p)=p^x(1-p)^{1-x}$$, and my book defines the Fisher information about $p$ as   $$I_X(p)=E_p\left[\left(\frac{d}{dp}\log\left(p^x(1-p)^{1-x}\right)\right)^2\right]$$   After some calculations, I arrive at  $$I_X(p)=E_p\left[\frac{x^2}{p^2}\right]-2E_p\left[\frac{x(1-x)}{p(1-p)}\right]+E_p\left[\frac{(1-x)^2}{(1-p)^2}\right]$$  I know that the Fisher information about $p$ of a Bernoulli RV is $\frac{1}{p(1-p)}$, but I don't know how to get rid of the X-values, since I'm calculating an expectation with respect to $p$, not $X$. Any clues?


Integral $\int_0^{\infty} \frac{\log x}{\cosh^2x} \ \mathrm{d}x = \log\frac {\pi}4- \gamma$

Inspired by the user @Integrals, I thought I'd find some nice integrals! Especially interesting are those involving $\log \pi$. From Borwein and Devlin's "The Computer as Crucible", pg. 58 - show that  $$\displaystyle \int_0^{\infty} \frac{\log x}{\cosh^2x} \ \mathrm{d}x = \log\frac {\pi}4 - \gamma,$$  where $\gamma$ is the Euler-Mascheroni constant.


English equivalent of this Tagalog proverb

We have a saying in Tagalog:     Aanhin pa ang damo, kung patay na ang kabayo.   which literally translates to English as     What is grass good for, if the horse is already dead.   Basically, the idea is, something (help, benefit, etc.) arrives too late for it to be useful. What is/are the equivalent/s of this saying in English?


When it is necessary to assume distribution to calculate probability?

I hope that my question is clear enough to understand.   If we need to calculate the probability of an event and we have historical data regarding our parameter of interest - When we have to assume distribution in order to calculate the probability of an event, or it is safe just to calculate the probability from a simple frequency distribution.   To put the question into context here is an example:   We want to calculate the probability of X numbers of sales in a certain period of time.  Assume Poisson distribution? Or it is enough and "safer" just to calculate the probability of X sales from the historical frequency of sales during that period?  Thank you very much!


I am having a problem comprehending with the relation of kernel, weight and linear separation.      I have a case where I am given a kernel $k_1$. that has a corresponding mapping $\phi_1$.  And we know that it's linear separated in that space.      I need to show that given some $a,b > 0$:  $$k=a*k_1+b*k_2$$ to show if we have linear separation in the higher dimension.  How do I approach that?


Can someone give an analytical proof that $\pi$ is greater than 3?

The geometrical proof is simple, but I want to know how to prove $\pi \gt 3$ by using basic calculus?


Is this proof of the $\lim_{(x,y)\to (0,0))} \frac{x^6y}{x^8+y^4}$ correct?

Let $\varepsilon>0$ be arbitrary. Note that $||(x,y)-(0,0)||<\delta \implies \sqrt{x^2+y^2}<\delta$, which in turn yields $|x|<\delta$ and $|y|<\delta$.   Now, let $\delta=\varepsilon$ and assume that $||(x,y)-(0,0)||<\delta$. From what we just proved, $|x|<\varepsilon$ and $|y|<\varepsilon$. Finally, we have:  $$\bigg|\frac{x^6y}{x^8+y^4}\bigg|=\frac{|x|^6|y|}{|x|^8+|y|^4}<\frac{\varepsilon^7}{\varepsilon^8+\varepsilon^4}<\frac{\varepsilon^7}{\varepsilon^4}<\varepsilon^3$$  Since $\varepsilon^3\to 0$ as $\varepsilon\to0$, the limit is $0$.


Find the height of a cylinder of maximum volume inscribed in a sphere of radius R.   How do I solve this? I found something online but I don't get why R is the red line in their drawing.


Why the orbital angular momentum equal zero for electron in s state? does it mean that the electron doesn't orbiting in s

Why is the orbital angular momentum $l$ equal to zero for electrons in the $s$ state? Does it mean that the electrons aren't actually orbiting?


Poem about a time traveller and an alien fighting as mercenaries with swords

Read this in the 80's in a compilation of military Science Fiction short stories.  The author/speaker is a human time traveller who has gone back in time and become a mercenary at a time when swords and pikes are the weapons.  The time traveller's unit gets wiped out and while looking at the body of his buddy realizes the buddy was an alien (because of the green blood). there is a line about where he says you never told me you were (type of alien) and I never told you I was from the future.


SFTP server for 1 to 5 people team : is an i5 Gen2 enough or is an i7 recommended?

For a one-man company which is planning to hire a small staff, I'm considering transforming a former small form factor desktop into a server to deliver files through SFTP. As a basis for evaluation, let us estimate that the staff will gradually increase to 5 people.  I have several possible candidate machines, which all have quad-core Intel vPro i5 or i7, Gen2 processors.  I wonder if i5 is enough to ensure a smooth user experience in this context ( — I assume so because better than most processors we can see in small NAS —), or if an i7 is recommended.  Details of the upgraded desktop:   SFF computer with Intel i5/i7 (Gen2) quad-core processor professional SATA SSD with MLC NAND (e.g. Intel DC S3500, Samsung 860 PRO, SanDisk Extreme PRO) 8 GB RAM DDR3 10600U CentOS in console mode (or with a lightweight desktop)   Processors of candidates machines:   i5-2500 3.3 GHz (max. 3.7 GHz Turbo), 6 MB cache, 4 cores, 4 threads i7-2600 3.4 GHz (max. 3.8 GHz Turbo), 8 MB cache, 4 cores, 8 threads   Detail of requirements:  The purpose is to allow a small staff (max. 5 people) to access to CAD drawings and excel files remotely.  I plan using an SFTP mapping software on the client laptops, so that each user can see the files like if they were on his own computer. The files are transfered through SFTP, behind the scenes.  So basically, the server will act like a NAS, but offer the comfort of a true computer, making easy to connect a screen, keyboard or backup drive. There is no need for remote desktop. All ressource-hungry things (e.g. viewing a CAD drawing) are client-side.  In the past, for a larger team, I have used a true server (e.g. Dell PowerEdge T310 with Xeon X3400, 8GB RAM DDR3 ECC, SAS HDD in mirror, CentOS). But this time, the team is smaller, 1-3 people (max. 5). We want to save space, limit noise, power consumption, and save some money as well.  N.B. I'm aware of VPS servers, but running own server offers more comfort, especially for backups, privacy and additional "local" security in case of a network outage at the ISP. So, running own server is a deliberate choice.


In proper English usage it's widely recognized to use 'an' in front of any noun which begins with a vowel. Ex. An apple instead of 'a' apple. The converse is true in regard to nouns beginning with a consonant. Ex. A banana versus 'an' banana.  However, my question revolves around nouns whose first letter 'sounds' like a vowel; but isn't. Ex. 'an' hour sounds considerably better than 'a' hour.  Thus, is there an established rule of English utilization saying a person must/should use an article such as 'a' in front of nouns which begin with consonants sounding like vowels?


Why does Bill Cage wake up in the helicopter?

In  William Cage is reliving the same day over and over again.   The time loop always starts with Cage waking up at Heathrow, after his meeting with the General.            But in his last jump he wakes up in the helicopter, en route to the General.                 (the images are from the trailer)  My Question:   Why did killing the "Omega" change the starting point of Cage's time jump? (I'm guessing the difference is only a couple of hours: Cage meets with the General, blackmails him, gets arrested and is transported to the military base at Heathrow)


Should I write "all the data is correct" or "all the data are correct"?

Which sentence is correct:     In this section you can make a payment: verify carefully that all the data submitted is correct and confirm by clicking the Proceed button.   or     In this section you can make a payment: verify carefully that all the data submitted are correct and confirm by clicking the Proceed button.


Proving $\mathbb{Q}$ not isomorphic to $\mathbb{R}^{+}$

Question: Prove that $\mathbb{Q}$ under addition is not isomorphic to  $\mathbb{R^{+}}$ under multiplication.   I wonder what is a good way to approach this? Would constructing a map be more helpful?  Thank in advance. Hints only*


Confused about the application of Hadamard gate to uncorrelated qubits

Why does applying the following circuit on a $00$ state produce $|0\rangle \otimes  |+\rangle = \frac{1}{\sqrt{2}}(|00\rangle + |01\rangle)$. Shouldn't it produce $ |+\rangle \otimes  |0\rangle = \frac{1}{\sqrt{2}}(|00\rangle + |10\rangle)$?


How to handle users who don't select answers for their questions?

How should SO handle users who don't "maintain" their questions by selecting answers, or remarking newer/better answers as the chosen one?  Many questions...   Have no answer marked correct, even when one is plainly there Are not reviewed by the poster to select a new correct answer   I don't mind taking the time to answer questions, but don't see the point when I don't get "reputation" for doing so since no one reads those questions, and reputation seems to be the point of the site.  I think the "remind to accept an answer" feature is there now, since I just saw it when coming back.  I missed it the first time though.


How to hide and show a certain object by Toggle

I want to make a toggle button that hides/shows cube objects. but this seems not to be working. Here is my code: import bpy if bpy.data.objects['Cube'].hide_set == True:     bpy.data.objects['Cube'].hide_set(False) else:     bpy.data.objects['Cube'].hide_set(True)


How do I delete totem's history displayed in it's main menu in Natty? For example if I don't want anyone to know I'm watching... ehem Simpsons a lot?  I've tried  but this doesnt work for Totem.


According to known discoveries made till now , we have came across all the charged particles which have the property of mass . So can we assume that there is a correlation between charge and mass and hence can we say that a mass-less can't exist.


Is it possible to plot a graph of any shape?

In school, I have learnt to plot simple graphs such as $y=x^2$ followed by $y=x^3$.  A grade or two later, I learnt to plot other interesting graphs such as $y=1/x$, $y=\ln x$, $y=e^x$. I have also recently learnt about trigonometric graphs and circle equations. In the internet, I have seen users posting graphs of different shapes like a heart-shaped graph and a Batman logo-shaped graph. I am sure there are numerous more graphs that I have yet to see. Seeing that the graphs can be shaped into shapes like the Batman logo and a heart brings me to my question: Is it possible to plot a graph of any shape regardless of its complexity? Perhaps, shaped into an outline of a person or a landmark? Why or why not?


Execute powershell before Azure VM shutdown

Right before shutting down the VM, I would like to shut down certain windows services(in the same VM) our application using(graceful shut down). Is there an event in Azure VM that I can hook a powershell script to, so that it executes before shutting down the VM? The current solution is to keep a schedule for Services shut down and then another schedule to shut down VM(every day). But when we need to deploy in between, then this approach fails.


Pairing an Apple bluetooth keyboard with a Windows 7 PC

Is there a trick to pairing an Apple bluetooth keyboard with a Windows 7 PC (64 bit)?  It is a Lenovo Q700 using an ioGear USB dongle.  The dongle is functioning fine, but when I turn on the Apple keyboard (which puts it into discoverable mode automatically), Windows cannot find it.  Is there a trick or known incompatibilities with the bluetooth dongle I'm using?  The keyboard can pair fine w/ my ipad, etc.


When I search on CodeReview.StackExchange.com for "[f#]" (so the tag F#), I get a captcha page. After the captcha I get redirect to the search result page. This now has the query string "f#", so it lost the square brackets - suddenly I'm searching for text, not for a tag.  When I search for "[f#]" and I don't get a captcha it works as expected.


Suppose there are 200 files in /tmp  e.g.:  {abc1xyz,abc2xyz,abc3xyz..abc200xyz}  I want to write "hello" in the files from abc38xyz to abc53xyz


This is from a news article:  "Mr. Trump’s desire to be friends with the “short and fat” ruler of North Korea"  My doubt is that, can we use friends here because friend seems better here. Other examples to take can be:  I want to be friend with him. I want to be friends with them  Which is the way to use "friend" with a "s"


Finding/giving an appropriate thank you gift to university faculty

I'm a student at a large university, and recently had an especially hard semester due to a family emergency. I withdrew from two classes, and the only reason I didn't have to withdraw altogether was because of some very understanding faculty members in my department.   My department adviser, after realizing that I probably wouldn't be able to go to all of my professors explaining this issue and begging for extended deadlines without breaking down, emailed all of them herself and basically bought me a couple of weeks to pull myself together. One of my professors went above and beyond and gave me "indefinite deadlines" (i.e. whenever I feel like turning it in) for all of his class assignments. My grade for his class is made up of three essays, and, even though there's only a month left in the semester, I've turned in none of them; every attempt I've made to approach him and apologize for all of the trouble I've caused him has been casually waved away.   So, my question is: what's an appropriate thank you for everything they've done for me? I've tried to end every meeting I've had each of with them by thanking them, but they always seem a bit embarrassed and wave me off (they're both pretty reserved people). Knowing that they're embarrassed by even my little attempts to thank them, I'm not sure if they'd like me getting them a thank you card or a gift card. Also, scheduling an appointment with my adviser (that's the only way I'm able to see her) just to give her a thank you gift feels a bit weird. Any tips? Are my in-person "thank you's" enough, or should I try to get them something more? And, if a gift would be appropriate, is there any etiquette regarding how I get the gift to them?


How to mount an NTFS partition read-only in Windows?

I feel like this is a really simple and fundamental function that Windows should have, but so far Google has been telling me it isn't possible.  How can I mount an NTFS partition read-only in Windows?     works! (Thanks.)  Additional info about diskpart:   If you have multiple volumes in a disk, neither detail vol nor attr vol shows the correct read-only status. It shows the read-only status of the last modified volume. Try these: sel vol 1, attr vol set readonly, sel vol 2, attr vol clear readonly, sel vol 1. Now detail vol shows that volume 1 is not read-only, but it actually is. If you modify a volume with Linux's ntfs-3g and then bring it to Windows, it cannot be mount read-only. If you run attr disk set readonly, none of the disk's volume can be mounted.


Let $ A $ be a ring.  Let $ I $ be a preordered set, filtering.  Let $ \Sigma $ a multiplicative subset of $ A $.  Suppose for any given $ i \in I $ a multiplicative subset $ S_i $ of $ A $ contained in $ \Sigma $.  Make the following assumptions:   $ \Sigma = \displaystyle \bigcup_i S_i $ For $ (i, j) \in I^2 $ with $ i \leq j $, elements $ S_i $ become invertible in $ S_ {j}^{-1} A $.   $ \mathcal{D} = ((S_{i}^{-1} A)_{i \in I} \ , \ (S_{i}^{-1} A \to S_{j}^{-1} A)_{i \leq j}) $ is a commutative diagram in the category of filter $ A $ - algebras.  Question :  Show that $ \displaystyle \lim_{\longrightarrow} \mathcal{D} \simeq \Sigma^{-1} A $.  Thank you in advance for your help.


When a paragraph begins, there is an indentation in the first line. How do I know the size of the indentation? Does it depend on the size of the font? Does it depend on something else?


Show that $(a+b+c)^\alpha<a^\alpha+b^\alpha+c^\alpha, 0<\alpha<1$

For any positive real $ a, b, c$, show that $(a+b+c)^\alpha<a^\alpha+b^\alpha+c^\alpha,  0<\alpha<1$.  I can show that it works for special cases like $\alpha=1/p, p\in\mathbb{N}$... but I don't know how to generalize further...


I have a requirement where a certain field can be edited without the validations firing for a particular user. Now I tried to write rule like LastModifiedId != '005000000000000AAA' but the validation was still firing. Then I realized that until the record saves, the LastModifiedId does not change and the validations still fire, as the LastModifiedId would not be updated to the exempted User.   Is there any workaround or a way to check the Id of the User who is currently editing the record?


Many times in the past I've edited a somewhat recent answer—say, from 30 minutes ago—and noticed that the concomitant question didn't bump to the top.  I just confirmed it with ; the question is currently sorted in the JavaScript page based on when it was asked, not my edit.  I've never made edits just to bump a question to whore rep—my original answer was wrong which was why I fixed it—but my understanding is that the CW self-edit trigger exists to prevent  edit-then-bump-then-score-rep—profit! activity.    If non-ancient edits no longer bump a question, should the self-edit CW trigger be brought inline with this?  Should an answer be made CW if you make 10 edits that actually bump the question?  and to avoid any implication of impropriety, I'm already capped on SO, so I'm not looking for any sort of "meta effect" on my answer


How to install the latest g++(currently 5.1) in Ubuntu(currently 14.04)?

This question always bothers me! Last time for 4.9 I tried the commands mentioned in . The same trick doesn't work now:  sudo add-apt-repository ppa:ubuntu-toolchain-r/test sudo apt-get update sudo apt-get install gcc-5.1 g++-5.1   results in...  E: Unable to locate package gcc-5.1 E: Couldn't find any package by regex 'gcc-5.1' E: Unable to locate package g++-5.1 E: Couldn't find any package by regex 'g++-5.1'   What is the correct command for directly installing the latest g++ in Ubuntu? Is there any magic command which works uniformly for all the updates of g++?  Update:  I found that the correct command to install it is:  sudo apt-get install g++-5   This works now! Though in the , the version is 5.1.


From activity_settings.xml  <EditText android:id="@+id/editText" android:text="text" /> <Button android:id="@+id/button" android:text="button"/>   From MyActivity.java  @Override protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_settings);     this.findViewById(R.id.button).setOnClickListener(         new View.OnClickListener() {             @Override             public void onClick(View view) {                 EditText txt = (EditText) view.findViewById(R.id.editText);                 Toast.makeText(view.getContext(),txt.getText(), Toast.LENGTH_SHORT).show();            }         }); ...   If I click the button I get   java.lang.NullPointerException: Attempt to invoke virtual method 'android.text.Editable android.widget.EditText.getText()' on a null object reference   Just for test I tried and succeeded  @Override public void onClick(View view) {     EditText txt = (EditText) view.findViewById(R.id.editText);     Toast.makeText(view.getContext(),txt.getText(),Toast.LENGTH_SHORT).show();     } }   I don't get why button is ok but editText is null.


Localization by a non-nilpotent as a polynomial quotient

In Dummit and Foote, Exercise 15.18 (p. 727 3rd edition) one is asked to prove that for a commutative ring with unity $R$, and $f$ a non-nilpotent element of $R$, that the localization $R_f$ is isomorphic to $R[x]/(xf - 1)$.  I have done this, using the strategy outlined in the problem, using the universal property of $R_f$ proved in Theorem 36. The problem I have is this:  If $R_f \cong R[x]/(xf - 1)$ and $\phi:R[x] \to R_f$ is a surjective homomorphism, it stands to reason that $\text{ker}(\phi)$ should be $(xf - 1)$. I cannot show this directly. The surjective homomorphism I have in mind is, for:  $p(x) = a_0 + a_1x + \cdots + a_mx^m$  $\phi(p) = \dfrac{a_0}{1} + \dfrac{a_1}{f} + \cdots + \dfrac{a_m}{f^m}$  It is clear to me that $\phi$ annihilates $(xf - 1)$, so that ideal is contained in the kernel. What I cannot show is the other containment, or equivalently:  If $\phi(g) = 0_{R_f}$ then $g(x) \in (xf - 1)$. The trouble I am running into is that $R$ might be a "bad" ring, containing a lot of zero-divisors, $f$ might even be a zero-divisor (being non-nilpotent is a considerably weaker property), so the usual polynomial tricks of the division algorithm or using the irreducibility of $xf - 1$ aren't much use, here.  I feel I am missing something obvious....what is it?


Similarity between $A$ and $B (2\times 2)$.

I am trying to find out whether $A = \begin{bmatrix}     3 & 1 \\     0 & 2 \\ \end{bmatrix}$ and $B = \begin{bmatrix}     4 & 1 \\     -2 & 1 \\ \end{bmatrix}$ are similar. Both matrices have the same trace, same rank, same determinant and the same eigenvalues. So I think they are similar. The eigenvalues are $3, 2$. Now I'm not sure how to find if they are indeed similar.   I am trying to find if there is a basis for $\mathbb{R^2}$ that contains only eigenvectors but when trying to solve $(3 I - A)v = 0$ there is no solution... What should I do from here?


This is what my GRUB 2 menu looks like so far:  I want to do a few things here:  I want to rename "Windows Boot Manager (on /dev/sda1)" to just "Windows 8.1". I'd like to rename "Ubuntu" to "Lubuntu 14.04.1". I'd also like to switch the order of the options to this:  Windows 8.1 Lubuntu 14.04.1 Advanced options for Lubuntu    (Windows will be the default OS) If it helps in any way, I'll explain the steps I took prior to this, since I am very new to Linux and don't know what information is required.  I bought a laptop on Amazon (ASUS X551MAV-EB01-B) pre-installed with Windows 8.1 64-bit I downloaded the proper Lubuntu .iso file for my system (Lubuntu 14.04.1 amd64) and put it on my flash drive (via UNetBootin) I went to Disk Management, and shrunk the C:/ drive down 32Gb so that 32Gb will be free for Lubuntu I used my flash drive (32Gb Sandisk Cruzer) as a LiveUSB for Lubuntu 14.04.1 I went through the install process. It didn't recognize Windows 8.1 so I had to do the "Something Else" option. I highlighted the free space, and pressed the + button I created a 10,000mb ext4 partition and mount point is / (is now dev/sda7) I created a 4,000mb swap area partition (is now dev/sda8) I created an ext4 partition using the rest of the free space and the mount point is /home (is now dev/sda9) I selected dev/sda7 to install Lubuntu and selected dev/sda7 for the bootloader installation It installed just fine, booted up just fine, and I'm happy to know the GRUB menu works.


I can't see the password when I enter it in Terminal wth the command "su"

I'm trying to install Java, but it requires the "su" command. When I enter my password, the password field remains blank. I try to enter my password, but it remains blank. I press enter, just in case in the sight chance it's techincally entered and I can't see it. It gives me an Authentication Failed message and it makes me enter my password again. Finally, I just exit the terminal. I've read  and did not answer my question. My instructions are And maybe I'm using the wrong version of Java, so if that is, please point me to the correct version. Here's my system stats:  I'm using terminal, on Ubuntu 14.04 LTS.  Also, I installed Ubuntu about 4 hours ago, so I'm new.  Any help would be greatly appricated.  Thanks in advance, Ryan


equivalence relation proof for all positive integers

The relation $R$ is defined for all positive integers such that $(a,b) R (c,d) \longleftrightarrow a+d=b+c$. Show that $R$ is an equivalence relation.


Error : Unable to send e-mail. Contact the site administrator if the problem persists

I have Drupal 7.43 installed on my hosting account, and I am using phpmailer to send all emails. It is giving the following error:       Type phpmailer   Date Monday, March 21, 2016 - 15:39   User shyamzawar   Location    Message SMTP error: Could not connect to SMTP host.       Subject: PHPMailer test e-mail      Body:        Your site is properly configured to send e-mails using the PHPMailer   library.      Message:     array (        'id' => 'phpmailer_test', 'module' => 'phpmailer',      'key' => 'test', 'to' => 'shyamzawar@ymail.com',        'from' => 'shyam007zawar@gmail.com', 'language' => NULL, 'send' => true,        'headers' => array(          'X-Mailer' => 'Drupal',        ),      )       Severity error


I want to have Clonezilla and GParted on one USB stick. I remember that there was a joint project, but it is now closed. Is there an ISO with both that I can download?  I don't want a multiboot USB. I want one Linux with both tools. Sorry for the , but this was the project in 2007 which mentioned.


How did the Tesseract end up with Mar Vell?

In the end of Captain America, Tony Stark's father retrieves the Tesseract.  In Captain Marvel we are shown that Lady Marvel was working with the Tesseract.  How does the Tesseract go from Mr.Stark to Lady Mar Vell?   EDIT: What I'm looking to find out is how does she take the Tesseract out of the Earth and stow it away on a space station without anyone knowing. Is there any clue that could tell us how Mar Vell gained so much clearance to Project Pegasus, that she could relocate the Tesseract without anyone in S.H.I.E.L.D knowing?


liquid texels visible through glass - any solution?

Successfully filled a glass with wine, and the liquid (wine) creates a nice smooth skin on top, but!... the bottom of the wine, which is also visible through the glass, doesn't bother to smooth out, and looks kinda lego'ish.    Any ideas on how to coax the liquid physics to apply its smoothness where the wine meets the surface of the glass?


How to use GetSObject to retrieve related data in a null safe manner?

I have a lookup relationship.  If I just do the following query it works fine:  Sobject c = [select field__r.fieldchild__c from custom_obj where Id = :someId]; system.debug('c:' + c);   However with the following I get an error:  Sobject c = [select field__r.fieldchild__c from custom_obj where Id = :someId]; String c2 = (String) r.getSobject('field__r').get('fieldchild__c');   Error message:     FATAL_ERROR System.NullPointerException: Attempt to de-reference a   null object


My 2-and-a-half-year-old child refuses to take her food. We have to force her to eat. I even tried changing her food to suit her tastes but still need to force her. Please help.


Can someone help me solve the equation $x^2 - 1 = e^x$ ?  I tried taking the natural logarithm of both sides but I don't know where to go from there..  I got:  $\ln(x^2 -1) = x$ But I don't know how to solve it from here. Any help please?


Reference table rows by automatic counter

Problem  I have defined an environment to automatically number example sentences throughout my document. It uses the tabular environment and automatically numbers the first column of each row using a custom counter. I have reasons for not using lists or the theorem counter.  I want to label and reference a table row so that the number associated with the row is displayed. Using \label and \ref does not work. Is there some way to feed a function two args, a key and the current value of my counter, and later use the key to recall the other arg? Or is there another way to do what I want? Not breaking the labels and references for the rest of the document is ideal but not necessary.  (Non-)Working Example  \documentclass{article} \usepackage{array} %don't know why this is needed; get csname error otherwise  % automatically number examples throughout document \newcounter{exno} \newenvironment{examples} { \begin{flushleft} \begin{tabular}{>{(\stepcounter{exno}\theexno)}rl} } { \end{tabular} \end{flushleft} }  \begin{document}  \section{Foo} Here are some numbered example sentences. \begin{examples}   &Content of row 1 \label{row1} \\   &Content of row 2 \label{row2} \end{examples} Now I want to get a 1 here: \ref{row1}. I want to get a 2 here: \ref{row2}.  \end{document}


LaTeX complains Limit controls must follow a math operator. \textbf{G} := \parallel\limits about the following snippet.   \documentclass{article}  \usepackage{mathtools} \begin{document}     \begin{equation}         \textbf{G} := \parallel\limits_{\pi \in \mathcal{P}} \textbf{G}^{\pi}      \end{equation} \end{document}   What is a possible workaround to apply \limits to \parallel?


"I'd the house to myself" Is this incorrect?

"I'd the house to myself."  Since "I'd" can be a contraction of I had, would it work in this case for "I had the house to myself?"


Festival stores voicepack data in the following example directory structure:  /usr/share/festival/voices/<language>/<voicepack name>  What is the simplest one-liner (preferably using ls) to print out just the <voicepack name>'s, in all the potentially numerous <language> subdirectories?


"implements Runnable" vs "extends Thread" in Java

From what time I've spent with threads in Java, I've found these two ways to write threads:  With implements Runnable:  public class MyRunnable implements Runnable {     public void run() {         //Code     } } //Started with a "new Thread(new MyRunnable()).start()" call   Or, with extends Thread:  public class MyThread extends Thread {     public MyThread() {         super("MyThread");     }     public void run() {         //Code     } } //Started with a "new MyThread().start()" call   Is there any significant difference in these two blocks of code ?


How do I apply check_markup() as Twig filter?

I am trying to modify output in my twig file. In D7, I was able modify data in my array with this  check_markup($tweet->text, 'full_html');   and I see that this function still exists in D8. However, I'm not sure how I would use this in a filter in twig. This is what I have so far:  {% for tweet in params.tweets %}

          {{ tweet.text }}

 {% endfor %}   I actually tried to do this before I sent it to the template as well, but it didn't change anything:   foreach($tweets as $tweet) {   $tweet->text = check_markup($tweet->text, 'full_html');   $cleanTweets[] = $tweet; } dpm($tweets); $params = array('tweets' => $cleanTweets); $tweet_template = array('#theme' => 'twitter_pull_tweet_listing', '#params' => $params); return $tweet_template;   What I'm trying to do here is make drupal create links for web links in the twitter tweet text. This worked fine for me in D7.


Requesting explanation for why dark matter evidence is not explained by special relativity

Good afternoon.  I'm doing research for a possible hard science fiction project and was looking up information on dark matter.  Wikipedia--hardly an authoritative source, I know--mentions that the evidence for dark matter stems from an observation where galaxies were rotating around each other faster than what should be possible given visually observable mass.  Has there been an experiment or anything to try to explain the faster-than-expected rotation via Special Relativity?  I mean, we're sitting inside of a gravity well looking at galaxies very far away, wouldn't the perception of time be different since we're sitting in a different gravitational field?  I'm absolutely not a physicist--just a layman asking a question to people who might have a better idea than me.  Thanks.


Evaluating $\lim_{x \to 0}\frac{(1+x)^{1/x} - e}{x}$

How to evaluate the following limit? $$\lim_{x \to 0}\frac{(1+x)^{1/x} - e}{x}.$$


Double throwing a NullPointerException but it is not null

I don't understand what is happening here. Basically, my code looks something like this:  Double average = 0.; for(Map<String, Double> map : model.getMaps()){     average += map.get(key); // this line throws a NullPointerException } average /= model.getMaps().size();   If I then do:  Double average = 0.; for(Map<String, Double> map : model.getMaps()){     try{         average += map.get(key); // this line throws a NullPointerException     } catch(NullPointerException e){         e.printStackTrace();         System.out.println(map.get(key).toString());     } } average /= model.getMaps().size();   It prints a number, not null. This is making me very confused.  More checks:  if(map==null) System.out.println("Map null"); else {     if (map.get(key).toString() == null) {          System.out.println(key + " null");     } else {         String newValS = map.get(key).toString(); //throws a NPE     } }   It is very weird that I checked for everything not being null and still it throws a NPE.


Need to represent information about a matrix, attached image showing what is needed

The following matrix is of size $10 \times 10$, however it is representing an $m \times m$ matrix. Hence I need to signify that the first five columns represent terms $0$ to $\frac{m}{2} - 1$ and the second five columns represent terms $\frac{m}{2}$ to $m$. I have an attached an image of what I need to represent.  \documentclass[a4paper,12pt,times,numbered,print,index]{article}    \RequirePackage[left=37mm,right=30mm,top=35mm,bottom=30mm]{geometry} \RequirePackage{libertine}  \RequirePackage[small,bf,labelsep=space,     tableposition=top]{caption}  \usepackage{multirow}   \usepackage{subfig,amsfonts,amsmath,amssymb,braket} \usepackage{algorithm}% http://ctan.org/pkg/algorithms \usepackage{algpseudocode}% http://ctan.org/pkg/algorithmicx  \begin{document}  $$ H_{ab}= \begin{bmatrix}     1           & 1         & 0         & \dots     & \dots     & 0         &  0        & 0         & \dots     & 0 \\     0           & 0         & 0         & \dots     & \dots     & 1         & -1        & 0         & \dots     & \vdots \\     \vdots      & \dots     & \dots     & \dots     & \dots     & 0         & 0         & 0         & \dots     & \vdots \\     \vdots      & \dots     & \dots     & \dots     & \dots     & \dots     & \dots     & \dots     & \dots     & \vdots \\     0           & \dots     & \dots     & \dots     & \dots     & \dots     & \dots     & \dots     & \dots     & 0 \\  \end{bmatrix} $$ \end{document}     Does anyone have any idea how I could represent this in LaTeX? If it is not possible to get it to display exactly like in the image I don't mind, I am just looking for a way to represent th e information in the image as clearly as possible. Anyone know how to accomplish this?


What is the difference between & and * in C++ function arguments?

As an example I know that  void foo(int *num) { num++; }   foo(&num);   will pass num by reference. However, why do people use  void foo(int &num) { num++; }   I've heard that you should use that syntax over what I posted above, why is this?


Is any explanation offered for "hyper-sleep"?

In Big Hero Six,      Callahan's daughter was found to be alive in the space between portals in what Baymax describes as "hyper-sleep".   I don't believe the movie offers any further explanation for this, or why Hiro isn't affected.  Are there any other sources that explain this?


How do I check if a partition is encrypted? In particular I would like to know how I check if /home and swap is encrypted.


What is the memory module on a RAID card needed for?

As above, what is the reason for needing a memory module on a RAID card?  The card I am looking at (HP P410) comes with either 256MB or 512MB but unsure which to get and why.


I have no texture image but colors and shading in materials. I want to export it in fbx so those materials(no image texture) with my shaders will be applied in the result. I'm absolutely new to shading and baking stuff so I would like you to explain it to me if you could. There's also a little bit of glitter on the material made by Voronoi texture just for the record.  here's the .blend file of model


Applying for a USA B1/B2 Visa for an alien resident in Germany

I hold an EU Blue Card and an Indian Passport and have submitted a paper to a conference in the USA due to occur in September 2019. The Blue Card will expire in August 2019 but have already obtained an extension for the same.  In order to present the paper in the conference I need to apply for a B1/B2 visa for the USA and not sure if I may be allowed to apply for one in Germany since I am not a German Citizen.  Are there any specific documents that I might need in order to apply for the B1/B2 Visa since I am not a citizen of the country where I am actually applying?


Task: Display multiple symbologies (Gratuated symbols and Colours) on one layer  Problem: The symbology keeps overwriting itself, so I cannot get both symbologies at the same time  Methods Tried:   Export the graduated colour layer as .lyr and import. (Result:Overwrites) Multiple attributes:(Result: Gives me all combinations, and that is not what I want)   I really don`t understand why I cannot get what I want to do in a few simple clicks?


If $H$ and $K$ are ideals of a ring $R$, what are the elements of $\langle H\cup K\rangle$? What I am trying to ask is that how does its element look?


ON creating BITMAP INDEX on a table in mysql throws error

I have database named "demo_dev" and added a table named "countries".  I wanted to create a bitmap index on a column, say, region as it has fewer unique values, using following query.   CREATE BITMAP INDEX ON countries (region);   It threw an error as shown below:     You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'BITMAP INDEX ON countries (region)'   What shoud be done for it to run successfully?  I just refered the following link :   mysql version : 5.5


Distance traveled equals area under velocity time graph

I know that for the particular case where the velocity of an object along a straight line is constant, the area beneath the velocity as a function of the time passed curve equals to the distance traveled. That really makes sense, it derives from the fact that the distance traveled equals to the product of the constant velocity and the time, which derives immediately from the physical definition of velocity. But why is that true in any case? Why if I'll take any curve of velocity as a function of time and compute the area beneath it I'll get the distance that was traveled? Any intuitive and rigorous proof for that? Thanks in advance :)


Here is the code I use to perform a web request. I'm getting all of the HTML except for the comments section in the URL.  HttpWebRequest req = (HttpWebRequest) HttpWebRequest.Create(   "http://u-handbag.typepad.com/uhandblog/2013/11/choosing-bag-fabrics.html#comment-6a00d8341c574653ef019b022fc96f970d" ); StreamReader reader = new StreamReader(req.GetResponse().GetResponseStream()); htl = reader.ReadToEnd();   Can anyone explain why?


Not citing code libraries used for paper

I'm submitting a paper to a CS conference, where I've just got the feedback from my professor. He wants to delete the few lines citing the implementation libraries such as sk-learn as well as more specialized libraries (3 in total). He feels that the lines don't fit in (which I kinda agree with) and that they make it look more like I just "plug n' played" without doing real research. On the other hand, I feel that the authors of these libraries should get some recognition for their hard work.  What is the general feeling towards not citing the libraries used? Would you advise me to discuss this with my professor or just delete the citations?  -- Edit --  It should be noted that the contribution is substantial and I definitely deem it good enough to be published. I just haven't done that much coding of new methods, but instead found interesting insights on important datasets using known methods.


Way to limit bandwidth of programs on Windows?

Is there a technique in Windows that can selectively limit bandwidth of a running process?


PHP-FPM Primary script unknown, but SCRIPT_FILENAME is set correctly

I'm using Nginx 1.5.12.1 with PHP-FPM for PHP 5.6.5 on CentOS 6.6 x64.  When I visit any page, I get a 404 with the error:     File not found.   My PHP-FPM error log doesn't say anything useful, but my Nginx error log:     2015/04/02 10:25:44 [error] 24689#0: *35 FastCGI sent in stderr: "Primary script unknown" while reading response header from upstream, client: 172.31.42.64, server: _, request: "GET /_index.php HTTP/1.1", upstream: "fastcgi://127.0.0.1:9000", host: "www.dev.example.com"   At this point, you are probably thinking that SCRIPT_FILENAME is configured incorrectly.  It's not, or at least appears correct to me.  If I fire up a packet sniffer and dig into the connection between Nginx and PHP-FPM, I can see that the variables are set correctly:   SCRIPT_FILENAME is /opt/example/_index.php SCRIPT_NAME is /_index.php DOCUMENT_ROOT is /opt/example REQUEST_URI is /_index.php DOCUMENT_URI is /_index.php   The script is indeed located at /opt/example/_index.php, and the document root is /opt/example.  Do you see anything wrong with those variables, as passed to PHP-FPM?  Assuming that they are correct, I guessed that PHP-FPM didn't have access to the files.  I set everything to 777, including the entire example directory.  That didn't solve the problem.  What are some other reasons that PHP-FPM would return "Primary script unknown"?  How can I further debug the situation?  Are there any other permissions that PHP-FPM needs to do it's work?  Edit:  I've found that if I run PHP-FPM as root, my problem is resolved, so this is going to be some sort of permissions problem but I don't know what since the scripts and directories they are in are wide open.


Integral $\small \int_0^\infty \frac{(\pi x - 2\log{x})^3}{\left(\log^2{x} + \frac{\pi^2}{4}\right)(1+x^2)^2} \text{d}x$

Prove $$\int_0^\infty \frac{(\pi x - 2\log{x})^3}{\left(\log^2{x} + \frac{\pi^2}{4}\right)(1+x^2)^2} \text{d}x = 8\pi$$   I tried using a modified version of the integrand and an origin-indented semicircular contour on the positive real half of the complex plane.  Despite my best efforts, I am unable to retrieve the desired integral, as the negative factor from the negative imaginary axis is preventing me from being able to simplify the integrals.  On top of that, the residue doesn't come anywhere close to the exact result.  Are there better methods that I am missing?


Using hyperlink shortcut Ctrl+l causes loss of up/down arrow keys

After using ctrl+l to link highlighted text when writing and answer or question, I can no longer use my up/down keys unless I leave the page and come back to it.  I am having an issue in FireFox 47.0.1, although I have noticed this in all previous versions as well. Windows 7 x64 if that matters.  I disabled all of my add-ons and verified this issue before posting this report.


Update created date from Data Loader or DBAmp

I'm migrating data over from another CRM. The person who did it didn't populate the correct Created Dates for our contacts, so another field was created that does have the correct created date. Am I able to update that date with the correct date? I have "Create Audit Fields" option turned on but cannot get the dates to update with a tool like Data Loader or DBAmp


Gnome screenshot: turn off camera sound *without* admin rights

Is there a way to disable the gnome screenshot camera sound, with needed admin access?  There's an answer here, that involves moving a file from somewhere in /usr/...    I don't have enough privileges to do that on my system.  Is there another way?  Thanks.


I was writing a program for users and Calendars for users.At some point I needed to delete every Calendar whose owner is some person X(Other people can also have this Calendar but the will not be the owner then).I managed to write the following code: void removeCalenderByOwner(String owner){         for(Map.Entry<Integer,Calender> cal:allUserCalenders.entrySet()){             if(cal.getValue().getOwner().equals(owner)){                 getStateByCalender.remove(cal.getValue());                 allUserCalenders.remove(cal.getKey());             }         }     }     static void delete(String name){         for(Map.Entry<String,User> user:UserByUsername.entrySet()){             user.getValue().removeCalenderByOwner(name);         }     }  The first function removes all the Calendars whose owner is "owner" and the second one calls that function for every user.Since the first function modifies alluserCalendar and getStateByCalendar which is parmeters of class user I am getting ConcurrentModificationException for both my functions.Any ideas to fix this? Edit:I used Iterator and again I am getting the same error.I just did it as follows: void removeCalenderByOwner(String owner){         Iterator<Integer> cal=allUserCalenders.keySet().iterator();         while(cal.hasNext()){             Calender calen=allUserCalenders.get(cal.next());             if(calen.getOwner().equals(owner)){                 allUserCalenders.remove(calen.getId());                 getStateByCalender.remove(calen);             }         }     }     static void delete(String name){         Iterator<User> i=UserByUsername.values().iterator();         while(i.hasNext()){             i.next().removeCalenderByOwner(name);         }     }


My tweets are not showing up in other people's mentions

My replies are not showing up in other people's mentions. I tried tweeting several friends, my other accounts but my tweets just won't appear in their mentions? They do appear on my own Twitter page. It's been almost 24 hours now and it's pretty frustrating.


This morning I got a call from my friend. I built his computer. In the past, he used a local account without password. That is the thing he asked for and he likes to use the computer in this way. But This morning, suddenly, Windows 10 went to the login screen and asked him to set a password unless it won't allow him to login. I am worried that this is caused by a virus. Has anyone seen this happen before? Thanks!


Do I have several GPSs, or several GPSes, or something completely different? What is the rule to remember (will be useful later when I can have a GPS2, a GPST and maybe a GPSX too).


17.04 Display scaling reverting to 1 after resume from suspend?

I've recently done a clean install of 17.04 on a machine with an Nvidia 750Ti card and a Dell 4K monitor. I'm using the Nvidia binary driver 381.09.  All this works great apart from the fact that the display scaling I set in the Ubuntu Screen Display settings always reverts back to 1 when the machine resumes after suspend. I need to set it at 1.5 otherwise everything goes tiny (BTW why doesn't Ubuntu scale to a sensible default with 4K monitors?)  Does anyone else get this? I can't find any mention of it elsewhere.  BTW I've tried the Nouveau driver and that doesn't wake up my screen at all after suspend. So that route's a non-starter.     Edit: Looks like it's been  Will monitor to see if anything happens.


What software can I use to download torrents

I just installed Ubuntu 13.10, Saucy Salamander. I would like to install a different Linux distribution, but all of my download crash. I want to use a torrent instead. What software can I install to download torrents in Ubuntu? I used Utorrent in Windows 8 but I don't think they have that for Ubuntu.


Class that my list stores:     class newClass{ private:   int a;   double b; public:   newClass( int c, double d ){     a = c;     b = d;   } };   Creating the list:  list< newClass > newList;   Printing the list:  list< newClass >::iterator i; for( i = newList.begin(); i != newList.end(); i++ ){   cout << *i << " "; } cout << endl;   This is the only method for printing lists that I have found but due to me printing values from a class this does not work. How do I work around this?


Find and create empty files with the same name in another location

I want create empty files with the same name, but in another location.  Is it possible?   find some files use only filenames touch an empty file in another place   Something like this:  find . -type f -name '*.jpg' -exec basename {}.tmp | touch ../emptys/{} \;


Unable to install audacity from ppa, it shows some packages are not installable. This is the output. This happened when a recent update came and was unable to install. So I uninstalled and re-installed, then this happened...  sudo apt install audacity Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  audacity : Depends: libid3tag0 (>= 0.15.1b) but it is not installable             Depends: libportsmf0v5 but it is not installable             Depends: libvamp-hostsdk3v5 but it is not installable             Depends: libwxbase3.0-0v5 (>= 3.0.4+dfsg) but it is not installable             Depends: libwxgtk3.0-gtk3-0v5 (>= 3.0.4+dfsg) but it is not installable E: Unable to correct problems, you have held broken packages.


Using $\sqrt{1-t}\leq 1-\frac t2$ to show that $\frac{1\cdot3\cdot5\cdots(2n-1)}{2\cdot4\cdot6\cdots2n}\geq\frac1{2\sqrt n}$

I have a problem that tells me to use that $\sqrt{1-t}\leq 1-\frac t2$ for $t\in(0,1)$ to show by induction that $\frac{1\cdot3\cdot5\cdots(2n-1)}{2\cdot4\cdot6\cdots2n}\geq\frac1{2\sqrt n}$  So far I have shown that $\frac{1\cdot3\cdot5\cdots(2n-1)}{1\cdot2\cdot3\cdots n}\leq 2^n$ from a previous problem. I don't know if that can be used. But the first premise has to be used.


Is "Logan" the last movie with Hugh Jackman as Wolverine?

has played the role of Wolverine as a major character in various X-Men films since 2000 and contributed highly to the brand of the X-Men movie series. But is he playing the Wolverine character for the last time in Logan?  I am getting to know from my friends that  is the last movie in which he is playing Wolverine and they all say that this is his last contracted film.  Are these rumors true? Is there any official information that confirms that this is Hugh Jackman's last movie as Wolverine?


How can I adjust the mouse scroll speed?

This question has been asked many times with no answer. I've used my basic Google skills and haven't come across a fix. This is system wide. My mouse simply scrolls too fast.   I'm new to ubuntu and linux in general. Would switching styles or whatever it is called (Ubuntu, KDE, Xubuntu) help at all? Is there a terminal code I can enter?


Inform new users if they can upvote an answer they accepted

I surprisingly often stumble upon answers which were accepted but clearly not upvoted by the asker. For example, the answer has not received any upvotes at all or the asker’s vote count is zero. While I acknowledge that , most such cases happen with new users, who have only recently received the privilege to vote and who upvote after a friendly reminder.  Given the anonymity of votes and that I do not check the asker’s profile for every question with an accepted answer I stumbled upon, I assume that there is a huge dark figure for this phenomenon. Also, I naturally most often spot this on my own answers, which makes reminding the asker of their privileges somewhat awkward.  I thus propose that users which accept an answer are reminded by a pop-up that they can upvote it, if:   They haven’t already upvoted it. They have the reputation required for voting. They have cast less than a handful of votes.   I consider the latter criterion to be better than an upper reputation for which the message is displayed, since I know at least one user with several thousand reputation points, who has cast much less upvotes or votes on answers than he has accepted answers on some sites (not that his acceptance rate or general feedback on answers is spectacular).


Novel about an AI (robot) becoming more human than the owner

An engineer has been shot, he was working on creating AI. His neural connections were broken and some kind of robot helped him to repair neural networks. The robot has micromanipulators each of which could split into two which were twice smaller (like a recursive tree structure), then he started to work on AI, created brain-computer interface through these manipulators. Then, using this brain-computer interface with help of the robot he created AI. And they started to share mind with this AI through the brain-computer interface.  Meanwhile, the engineer was becoming more and more senseless while the robot (AI) instead started to be more and more human.  I read it about 5 - 10 years ago. It was quite short I was able to print it. And in my opinion, at that time, it was new.    PS: Some american scientist with a Japanese last name was editor of this book.


Adding unicode (Cherokee) characters in Latex?

Most of my Latex is in regular English, but there are a couple of lines of Cherokee here and there that I want to include. What packages do I need to install? I tried playing around with fontspec and babel but I think I must be using them incorrectly. I also tried minted, but nothing shows up. I'm working in Overleaf!


I downloaded a Model from BlendSwap and  when I was looking through materials, I these nodes which I have never seen before.  Examples:      How do I create one of these custom nodes?


How to boot Ubuntu alongside Windows 8 on Aspire One 765

I can't seem to get Ubuntu 12.04 or 13.04 installed properly alongside Windows 8 on a netbook Acer Aspire One 765.   First thing I tried was with a live usb/bootable usb. This failed after disabling secure boot and putting USB HDD on no.1 on the list. The system does not recognize any usb device although the usb works fine on another laptop.  Then I tried UnetBootin and Wubi. After installation I get a Windows 8 boot menu in which I can choose between w8 and ubuntu.   When I choose Ubuntu I get a screen that says it cannot boot windows because of hardware- or software changes. It needs the Windows install disk.  File: \ubuntu\winboot\wubi1dr.mbr  Status: 0xc000007b  Installing with wubi was sort of my last option to finally get Ubuntu on this device but I seem to be stuck with w8 here.  All help is appreciated!


Soo I was thinking about this all night and I think I know how it works but im not sure, for example when i want to have a good pidgeot I should try to catch like a 10Cp Pidgey, so he would basicly be lvl 1 I guess? And when I have this pidgey I should evolve him into a pidgeotto and after that pidgeot, WITHOUT powering him up sooo he would be like 60 CP I guess? since he would get some CP thanks to the evolution.  And when I finally have this "lvl1" pidgeot I should max upgrade him? This way he gets the most powerfull moveset right??


I cannot respond to comments on my own question (no "add a comment" link anywhere)

I joined a new community and asked a question ()  People are commenting & asking questions, but I cannot answer them back. Even "Comment Everywhere" privilege requires 50 reputations and I have 101 reputations.  Am I missing something?


I've recently started to use LaTeX but I've just encountered a problem, I tried searching it, although apparently no-one asked it before.  I'd like to write using Japanese input, but when I typeset, there can happen 3 things:   I get some error when compiling; I get question marks where Japanese stuff should appear; Nothing appears.   For example I had an example .tex file, compiled it and it worked, so I added some japanese in order to see "The author is [Japanese here]", but what I could see was "The author is [blank space]".  I've tried checking some guides, but I haven't found anything that could solve my problem (they are too old, or they don't talk about this at all).  Some minutes ago I tried compiling this:  \documentclass[12pt]{article}   \usepackage[T1]{fontenc}   \usepackage{CJKutf8}   \usepackage[romanian]{babel}   \usepackage[overlap, CJK]{ruby}   \usepackage{CJKulem}   \renewcommand{\rubysep}{-0.2ex}   \newenvironment{Japanese}{%   \CJKfamily{min}%   \CJKtilde   \CJKnospace}{}   \begin{document}   \parskip 3ex   \parindent 0pt   \begin{CJK}{UTF8}{}   \begin{Japanese}   ねこ    \end{Japanese}   \end{CJK}   \end{document}   It compiles fine but, still same problem, nothing appears when typeset, even if I should see "ねこ". There are many Linux guides, but I have a Mac and apparently, there aren't a lot around...   EDIT: A small add, if I get this to work, is the solution related to other asian languages such as Korean or Chinese?


No Dual-Boot Option while Installing Ubuntu

I was trying to install Ubuntu on my Pc. I am having windows 10 as my current OS, I also want Ubuntu in my Pc. I successfully downloaded Ubuntu from its webpage and booted it to my pendrive.  I created an unallocated space for installing Ubuntu -   Then i restarted my pc and opened boot, changed uefi to legacy (I have Gigabyte). Then i ran my Pendrive. I got the installation page of Ubuntu. But there were no option for dual-booting Ubuntu with my Windows 10 OS.    I want to dual-boot Ubuntu with my Windows 10 so that i can use both without any loss. Please help me with this issue.


When booting Ubuntu, I get this message:    Is it possible to change the text Ubuntu 12.04 to Loading, please wait. ?


What is a word for someone who is in pain but puts out a tough image?

This person acts strong when really he is going through a hard time. What's an original word for this?


How to take screenshot, when app does not allow to do it?

My education app does not app me to take screenshot when I play video on it. So can you please tell me , there is any to take out the screenshot.


Restricting Internet access of applications in Ubuntu

I want to block access to the Internet for all apps and process on my machine except for ones specifically allowed. I used to achieve this with Firewall when I was using Windows. I have a very tight data plan (3rd world country problems) so I have to watch which apps use the Internet. How can I achieve this in Ubuntu 16.04 LTS?   Edit: Most of the answers I found here are either about blocking certain sites or blocking a certain app rather than blocking the entire app list and allowing only a handful apps.


My computer says my USB stick containing my borderlands character is empty

I am trying to edit my Borderlands 2 character save from my Xbox 360 but my computer says the USB contains no files. I have tried multiple different USBs and multiple different game saves from different games. My computer refuses to acknowledge that there are files on the USB.  Is there something I'm doing wrong, is there a process I have to go through in order for my computer to be able to read the game save or has Xbox found a way to stop save editing all together?


Image Uploader is stuck "Uploading", which I haven't initiated

The Image uploader/linker in the Post Editor across all SE sites appears to be stuck.  It says:     Cancel   Cancel and add another image   Uploading   Close   Your image is too large to upload (over 2 MiB)   As stated, I'm unable to insert an image to this post, but here is a screenshot uploaded directly to Imgur:   I have not initiated the image upload AFAIK, and none of the three "Cancel" buttons nor the Close button does anything. Yes, there is three Cancel buttons and it seems to be trying to both Link and Upload images at the same time.  I have tried to logout/login.


How can I prove submultiplicative of $p$-norm of matrix?

How can I prove $$\|AB\|_p ≤ \|A\|_p \|B\|_p$$ where $$\|A\|_p = \max_{x≠0}\frac{\|Ax\|_p}{\|x\|_p}, \qquad p = 1, 2, 3, \ldots$$ and known information below:  (i) $\|A\| ≥ 0$, with equality iff $A = 0.$  (ii) $\|cA\| = |c|  \|A\|$, for any $c ∈ \mathbb R.$  (iii) $\|A + B\| ≤ \|A\| + \|B\|$.  *Not duplicate of , I don't know whats the connection between that answer an my question.


This is a ready-baked regex that I got from the internet just to see how regex works in JavaScript (and jQuery). Here is my script:    <script>     $(document).ready(function(){         var regexp = new RegExp(([\w-\.]+)@((?:[\w]+\.)+)([a-zA-Z]{2,4}));         $("#submit").click(function(){             var result = regexp.test( $("#email").val() );             if(result){                 $("form").submit();             }else{                 alert("Invalid Email Address");             }         });     }); </script>      However, the form always submits despite entering a wrong email address.    I have read on how test() works. It know that it returns the right answer and then advances a pointer to the next value. So if it returns true, the pointer points to false. I do not see how that can be a problem here.    what is wrong here? :)    HTML:    <body>     <center>         <form name="subscription" method="post" action="http://www.cs.tut.fi/cgi-bin/run/~jkorpela/echo.cgi">             <input type="text" name="email" size="30" id="email"></input>             <button id="submit">Submit</button>         </form>     </center> </body>


Prove that for all primes p, every positive integer can be expressed as a sum of two squares mod p, $x^2+y^2 \equiv c \pmod{p}$, I think that this is essentially same with proving that all elements in the ring $\mathbf{Z}_p$ can be expressed as a sum of two squares. I've proven that half of the elements in $\mathbf{U}_p$ are squares, and also if $a$ is a square, then $-a$ cannot be a square. The problem is how to prove that these half could generate the other half.


jQuery : Multiple Upload Files with text edit values

So, I'm trying to POST using jQuery Ajax.   It's work fine if i don't use files upload.  How i get the multiple data uploaded and send it to server ?  Is it possible to do this..?  Thank in ADvance.  HTML :  <form id="uploadimage" method="POST" enctype="multipart/form-data" action="">   <input type="text" name="rsdtIncdSourceID"  id="rsdtIncdSourceID" >   <input type="text" name="rsdtTrnsId"  id="rsdtTrnsId" >    <input name="rsdtDescription" id="rsdtDescription" >   <select name="rsdtMsrsId" id="rsdtMsrsId">     <option></option>   </select>   <input type="file" id="input-file" required multiple> </form> <button class="btn btn-xl  wow fadeInUp" id="btnPost">Process</button>   JS :   $(function(){    var $rsdtIncdSourceID   = $('#rsdtIncdSourceID'); var $rsdtTrnsId         = $('#rsdtTrnsId'); var $rsdtMsrsId         = $('#rsdtMsrsId'); var $rsdtDescription    = $('#rsdtDescription'); var $rsdtFiles          = $('#input-file'); **// HOW TO GET THIS VALUE ?**   $('#btnPost').on('click', function(){      var match = {         rsdtIncdSourceID: $rsdtIncdSourceID.val(),         rsdtTrnsId: $rsdtTrnsId.val(),         rsdtMsrsId: $rsdtMsrsId.val(),         rsdtDescription: $rsdtDescription.val(),         rsdtFiles: $rsdtFiles.files[0],  **// HOW TO add THIS VALUE ?**     };      $.ajax({                 type:'POST',                  url:'http://xxxx:802/api/v1/transaction/matching/confirm',                 data: match,                 success: function(data, textStatus, jqXHR) {                     var userObj = JSON.parse(jqXHR.responseText);                     alert($rsdtDescription.val());                   },                 error: function(jqXHR, textStatus, errorThrown) {                     alert(textStatus);                   }      });  });    });


Dual monitors, stick windows to the side of the screen in windows 8.1

Currently I have two monitors (1 and 2) as on the picture:   When I am moving the windows on the screen I can stick them to the left of monitor 1 and to the right of monitor 2 (the window is resized to half of the screen and stick to edges of the screen) but can not stick them to the right of monitor 1 and left of monitor 2.  Is there a simple way to achieve this?


Is the Old World connected to the 40k universe?

Is the End Times connected to 40k or is it a complete different story? Because the Old World is hardly High-Terra and the corruption that Archaon brought is not the purity of High-Terra.


is there a why to make this thing solid? It has many holes and it's hollow inside.    Many thanks!  It has thickness, but I just want to make it a solid piece.


How to intersect existing shapes in Photoshop

I'm trying to intersect 2 existing shapes in Photoshop (CS6). I've found tutorials that allow me to intersect at the time of putting the second shape down, but nothing that allows me to do so with shapes already in the document.  The reason I would like this is that I would like to "tweak" the position of the second shape, by nudging it, adjusting its size etc. The only way I can do this at the moment is by undoing to remove the second shape, and starting again.  Is there a way to intersect 2 shapes that are already in the page?  (In Photoshop, not Illustrator. I don't have access to Illustrator at the moment)