Are limes and lime juice more acidic than lemons and lemon juice?

I attended a business meeting in the Midwest and one of our clients took our management team and a few other business partners to dinner at an awesome Mexican restaurant. When the appetizers were served I commented that it was a wonderful presentation and that everything looked very fresh, including the avocado slices.   Speaking to the woman seated across from me I said that even though I use a good amount of lemon juice, whenever I prepare avocados they still turned dark pretty quickly. This happens whether they are sliced, used in guacamole, etc. She responded that the secret is to use lime juice. She proceeded to tell me that she was born and raised in Central America and that it is customary there to use fresh limes or juice rather than lemon.  I have tried it and lime seems to work much better than lemon, so it would stand to reason that they are more acidic. However, I never thought there was that much difference. So, on to the questions.  Are limes more acidic than lemons? Are there any other differences in their properties that could make a difference?


Unexpected behaviour when creating a list with zeroes


General proof R intersection $R^{-1}$ is an equivalence relation on $X$.

If $R$ is reflexive and transitive relation on set $X$. then show that $R$ intersection $R$ inverse is an equivalence relation on $X$? I have started this by proving that $R$ inverse is also reflexive and transitive but cannot get how to show $R$ intersection $R$ inverse is an equivalence relation on set $X$.


What happens if I really don't like one of my settlements and refuse to defend it?

I'm really not a fan of Tenpines Bluff.  Those two citizens need to suck it up and learn to deal with raiders themselves if they won't move to one of my more well defended settlements.  Their settlement has no defenses and I refuse to build any, so what happens if they get attacked by raiders and I just stand by and laugh instead of rushing to their aid?


Is it possible to make an hyperlink like  on a comment?


How to implement some super admin feature to facilitate password retrieval for existing users?

I'm aware that Drupal 7 saves the user's password in a more compact way and it's really hard (impossible?) to convert such password back to a human readable text format (even not into database).  Actually I do not want to implement any hack to Drupal, but it's a requirement that a super admin can somehow view the username along with its password for any user. Super admin is a trust worthy role and actually will help through secured communication media to other users after forgetting their password.  So there is a need to create a block to show all the usernames with their corresponding password, which can only be used by a super admin.  Any suggestions about how I could implement all this?  Note:  Users are not allowed to reset passwords, I just want only super admin can access their usernames and passwords and then re-assign to other user if any of them forgot his password.


Passing a const pointer to a struct vs pass by value

What is recommended to use, passing a structure as a pointer to const i.e.    int doCalculations(const MyStruct* my_struct);    or passing the struct by value, as in,    int doCalculations(MyStruct my_struct);    and why?  In C++ I recall reading somewhere that passing references to const should be used when the struct/Class has a non-trivial constructor. In C although there are no constructors, I imagine it would still take some time to make a local copy of the struct.


My computer memory System Commit is maxing out

There seems to be a leak from a driver on my computer. When looking at the Memory tab of ProcessExplorer I see that the System Commit is slowly filling up to the maximum over the course of a few days. It always seems to take ~3 days to get to the 60GB of max commit charge. (My computer has 20GB of RAM and a 40GB pagefile)    I have traced that memory charge to something with the tag 1tfb using poolmon.    I thought it might have been a driver so I have done a "findstr /s 1tfb" in the windows drivers folder and it does not find anything.   Actually, calling 'findstr' used to return that no results was found, right now it does not seem to ever return. It just continues working forever. I don't know if that is related or not.  On the processes side, there are no big process hogging all the memory. The total memory used by my processes total up to the Physical Memory amount.  How can I trace who's using all that memory ?


Prove that $4k < 2^k$ by induction.   It holds for $k = 5$. Assume $ k = n + 1 $. Then  $4(n+1) < 2^{(n+1)}$  $4n + 4 < 2^n * 2$  $2n + 2 \leq 2^n$  Now I just need to show that  $2n + 2 \leq 4n$  $n + 1 \leq 2n$  $1 \leq n$  And because I chose $n = 5$ which is greater than $1$, this should prove that the formula holds for $n \geq 5$.  Is this correct?


ROC and multiROC analysis: how to calculate optimal cutpoint?

I'm trying to understand how to compute the optimal cut-point for a ROC curve (the value at which the sensitivity and specificity are maximized). I'm using the dataset aSAH from the package pROC.  The outcome variable could be explained by two independent variables: s100b and ndka. Using the syntax of the Epi package, I've created two models:  library(pROC) library(Epi) ROC(form=outcome~s100b, data=aSAH) ROC(form=outcome~ndka, data=aSAH)   The output is illustrated in the following two graphs:     In the first graph (s100b), the function says that the optimal cut-point is localized at the value corresponding to lr.eta=0.304. In the second graph (ndka) the optimal cut-point is localized at the corresponding value to lr.eta=0.335 (what is the meaning of lr.eta). My first question is:   what is the corresponding s100b and ndka values for the lr.eta values indicated (what is the optimal cut-point in terms of s100b and ndka)?   SECOND QUESTION:  Now suppose I create a model taking into account both variable:  ROC(form=outcome~ndka+s100b, data=aSAH)   The graph obtained is:    I want to know what are the values of ndka AND s100b at which sensibility and specificity are maximized by the function. In other terms: what are the values of ndka and s100b at which we have Se=68.3% and Sp=76.4% (values derived from the graph)?  I suppose this second question is related to multiROC analysis, but the documentation of the Epi package does not explain how to calculate the optimal cutpoint for both variables used in the model.  My question appears very similar to this question from , which says in short:     The determination of cut-off score that represents a better trade-off   between sensitivity and specificity of a measure is straightforward.   However, for multivariate ROC curve analysis, I have noted that most   of the researchers have focused on algorithms to determine the overall   accuracy of a linear combination of several indicators (variables) in   terms of AUC. [...]      However, these methods do not mention how to decide a combination of   cut-off scores associated with the multiple indicators that gives the   best diagnostic accuracy.   A possible solution is that proposed by Shultz in his , but from this article I'm not able to understand how to compute optimal cutpoint for a multivariate ROC curve.  Maybe the solution from the Epi package is not ideal, so any other helpful links will be appreciated.


Client Cross Frame Scripting Attack by Checkmarx scanner for visualforce component,

I am Using visualforce component for insert and updating child record. this component is reusable for multiple objects, like account, contact, etc., as like we can use this. I am doing DML inside a component. this component just receives a parentId through attribute, and we need to perform adding rows (childRecords) and need to save. Please suggest me how to resolve this issue


making google chrome prompt you when closing window with multiple tabs

Sometimes, when I'm trying to close a tab, I'll accidentally close an entire window of tabs in Google Chrome. Is there a plugin or something that I could install to make it so it pops up with a confirmation dialog before closing an entire window?  Thanks!


How to get DATE from DATETIME Column in SQL?

I have 3 columns in Table TransactionMaster in sql server  1) transaction_amount  2) Card_No  3) transaction_date-- datetime datatype  So, I want to fetch SUM of  transaction_amount where Card_No=' 123' and transaction_date= todays date.<----- excluding time IN SQL


How to locate below element TableHeader using xpath

I want to locate element 'TableHeader' in given DOM, I am using XPath but getting an exception unable to locate the element.  Xpath : //div[@class='PageContent']/table[1]/tbody/tr/td[2]   Please have a look if there is anything wrong in my XPath:  DOM:  <form>

                            Main

  </form>   I have two-page classes:  LandingPage.java:  import java.util.concurrent.TimeUnit;  import org.openqa.selenium.WebDriver; import org.openqa.selenium.WebElement; import org.openqa.selenium.support.FindBy;  public class LandingPage extends BasePage {      public LandingPage(WebDriver driver) {         super(driver);         // TODO Auto-generated constructor stub     }      @FindBy(name = "username")     private WebElement usernameTextbox;      @FindBy(name = "password")     private WebElement passwordTextbox;      @FindBy(name = "submit")     private WebElement loginButton;      public MainPage login(String usrname, String passwd) throws InterruptedException{         usernameTextbox.sendKeys(usrname);         passwordTextbox.sendKeys(passwd);         loginButton.click();         loginButton.click();         TimeUnit.SECONDS.sleep(3);         System.out.println(driver.getCurrentUrl());         return new MainPage(driver);     }  }     MainPage.java  package pageClasses;  import org.openqa.selenium.WebDriver; import org.openqa.selenium.WebElement; import org.openqa.selenium.support.FindBy;  public class MainPage extends BasePage {      public MainPage(WebDriver driver) {         super(driver);         // TODO Auto-generated constructor stub     }      @FindBy(className = "TableHeader")     private WebElement pageHeader;      public void testMainPage(){         System.out.println("inside main page");         System.out.println(pageHeader.getText());     } }


Due to some "recent issues", I think the following is necessary:  Users need a way to contact moderators through the StackOverflow website.  This is especially important for suspensions, where there is no way to appeal or discuss the suspension from within SO itself.  Basically, there would be some kind of a box on the user's page that allows them to mention something to the moderators and some way to read the replies. (Or they could just go to the user's email.)


Are the following sentences emphatic sentence or relative clause? Why? What's the difference?     It is the factory that you visited last week.      It is Tom who/that I saw yesterday.   Thanks for your englightenment.


Can “Community Wiki” become public domain?

What is the license of an answer marked community wiki? It seems a normal answer is , which can possibly not be kept for community wiki contributions, since the author becomes the community. What's the exact status of community wiki answers license wise? Or asked otherwise, is it possible to make a post  even?


Is it better to spawn your first overlord at 9 or 10 supply?

Assuming you're not doing some early cheese build, I'd think this would be something you could just do some math on to figure out which is better. Has this problem been solved? Which is better, and what is the math behind it?


Out of memory exception while reading large excel sheet in java

I am trying to upload excel sheet of 10000 records and 29 columns but giving me out of memory error, to solve this in increase memory size in eclipe.ini file but no use. I decrease columns upto 4 then it doesn't give me error. but for more columns error is coming . Here with attached screenshot of error


How can I produce exactly the same letter as in the attached picture ? I work with the TexMaker.    thanks,


`hostname` result is different from “/etc/hostname”!

If I open a terminal windows in my graphical user interface, hostname command result is different from content of /etc/hostname:  me@ZyXEL1:~$ hostname ZyXEL1 me@ZyXEL1:~$ cat /etc/hostname N4010 me@ZyXEL1:~$ cat /etc/hosts 127.0.0.1 localhost 127.0.1.1 N4010  # The following lines are desirable for IPv6 capable hosts ::1 ip6-localhost ip6-loopback fe00::0 ip6-localnet ff00::0 ip6-mcastprefix ff02::1 ip6-allnodes ff02::2 ip6-allrouters   and sudo command shows:   sudo: unable to resolve host ZyXEL1: No such file or directory   In tty1, tty2 and ... the command prompt is me@N4010:~$ instead of wrong one: me@ZyXEL1:~$, but sudo result is same as terminal window:  me@N4010:~$sudo sudo: unable to resolve host ZyXEL1: No such file or directory


I'm stuck on the last exercise of the level 14 in Vim-Adventures. According to the following picture, could anyone be able to tell me what I have to do here? Which command do I have to use (c,y,a,d or i) and how ?    Thanks in advance!


"E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages" after long time without using ubuntu

After months of not using ubuntu, I turned on my PC and when I typed the usual apt-get update then upgrade,  a red icon showed on my panel and when I clicked to upgrade packages, the Software Updater was shown with no packages listed but 243,6 MB to be downloaded.  Even when I clicked on Install now, somehow Software Updater crashed. And when I try to upgrade through terminal it shows "31 not upgraded'  What should I do to properly upgrade these packages?  EDIT  Here's the list of the non-upgraded packages  gcc-4.9-base gcc-4.9-base:i386 gimp gimp-data lib32gcc1 libgcc1 libgcc1:i386  libgimp2.0 liboxideqt-qmlplugin liboxideqtcore0 liboxideqtquick0  libreoffice-base-core libreoffice-calc libreoffice-common libreoffice-core  libreoffice-draw libreoffice-gnome libreoffice-gtk libreoffice-impress   libreoffice-math libreoffice-style-galaxy libreoffice-style-human  libreoffice-writer libva1 libva1:i386 linux-image-generic  oxideqt-codecs-extra pcsx2:i386 python3-uno


Divergence of the sum of some elements of some uncountable set

I came up with the following conjecture, but I'm not sure how to prove it or whether it is true at all.     Conjecture: let some subset of the real numbers $S \subset \mathbb{R}$ have an uncountable amount of elements, all of which are strictly positive, then it is possible to construct some countable subset of this set that diverges when summed.   My intuition says that this is probably true since when you create such an uncountable subset of the real numbers, you somehow have to smuggle in a range of real numbers or some set that is already divergent itself (like the irrationals). However, this is nowhere near a proof and I'm not sure whether I have even learned about the tools to rigorously prove this conjecture (or disprove). Therefore I would greatly appreciate it if someone could point me in the right direction.  Thanks in advance for your time and trouble.


Error Implementing force:showToast - Cannot read property 'setParams' of undefined

Component  <aura:component implements="force:lightningQuickAction">     <ui:inputNumber aura:id="num1"/> +     <ui:inputNumber aura:id="num2"/>     <br/>     <ui:button label="Add" press="{!c.showToast}"/> </aura:component>   Controller    ({         showToast : function(component, event, helper) {         var n1 = component.find("num1").get("v.value");         var n2 = component.find("num2").get("v.value");          // Display the total in a "toast" status message          var resultsToast = $A.get("e.force:showToast");         resultsToast.setParams({             "title": "Quick Add: " + n1 + " + " + n2,             "message": "The total is: " + (n1 + n2) + "."         });         resultsToast.fire();          // Close the action panel          var dismissActionPanel = $A.get("e.force:closeQuickAction");         dismissActionPanel.fire();         }     })   ERROR MESSAGE     This page has an error. You might just need to refresh it. Action   failed: c$TestCheck1$controller$showToast [Cannot read property   'setParams' of undefined] Failing descriptor:   {c$TestCheck1$controller$showToast}


I already did the apt-get purge, install and update thing but it still freezes when trying to start. This is what I get trying to start in terminal:  cliff@cliff-Aspire-X1301:~$ software-center 2013-06-26 17:00:29,092 - softwarecenter.ui.gtk3.app - INFO - setting up proxy 'None' 2013-06-26 17:00:29,097 - softwarecenter.db.database - INFO - open() database: path=None use_axi=True use_agent=True 2013-06-26 17:00:29,501 - softwarecenter.backend.reviews - WARNING - Could not get usefulness from server, no username in config file 2013-06-26 17:00:29,653 - softwarecenter.ui.gtk3.app - INFO - show_available_packages: search_text is '', app is None. Killed


Some apps won't run after upgrade to iOS 7.1, how to fix?

I update to the newest 7.1 yesterday.  Now some of my apps will not open.  Is there a way to delete this update?


How to disable Two-factor authentication for Apple ID?

I want to disable Two-factor authentication for my Apple ID.  When I log in to Apple ID website, and click edit, it lists Two-factor authentication as On, but does not allow me to turn it off.  How can I disable it?


How to disable mouseout events triggered by child elements?

Let me describe the problem in details:  I want to show an absolute positioned div when hovering over an element. That's really simple with jQuery and works just fine. But when the mouse goes over one of the child elements, it triggers the mouseout event of the containing div. How do I keep javascript from triggering the mouseout event of the containing element when hovering a child element.   What's the best and shortest way to do that with jQuery?  Here is a simplified example to illustrate what I mean:  Html:  Hover Me
   <input>Test</input>   <select>     <option>Option 1</option>     <option>Option 2</option>   </select>
   Javascript/jQuery:  $('a').hover( function() { $(this).next().show() }               function() { $(this).next().hide() } );


How to solve complex integration $\frac{1-|a|^{2}}{\pi}\int_{L}\frac{|dz|}{{|z+a|}^{2}}$, where $L$ is the simple closed curve $|z|=1$ and $a\in\mathbb{C}$ with $|a|<1.$ $z=e^{it}$ is the parametrization of the circle $|z|=1.$If we put values it becomes as $\frac{1-|a|^{2}}{\pi}\int_{0}^{\pi}\frac{|dt|}{{|e^{it}+a|}^{2}}$. Now i don't know to proceed further. Please help. Thanks a lot.


How to enable security in LaTeX using pdflatex 1.40.14

I want to disable copy/write/edit ... option in my .pdf document. I don't want the document to be password protected ...  I am using LaTeX to produce the document.  Here is the shapshot of the document-properties that I would like my document to have ...    I have tried with adobe acrobat ... but somehow I am not able to achieve the same document security properties ...


I am from India and I have heard and read about Ubuntu. I am really sick of using Microsoft products. I want Ubuntu as a replacement. will it solve my needs.  I have tried downloading ubuntu. But I am facing problem. I can't locate the exact webpage or link. I think there are many version of ubuntu. Can someone help me in finding the link and also a step by step guide for installing it.  I have some other doubts. Will it have Office applications and internet browsers in its bundle or I have to download it separately.


How to do you extract characters from a string in Google Sheets

I have a string in a cell: A|BCD|EF|GHI|JK.   I would like to extract it separate in individual cells: A should be in one cell, BCD in the next, EF in the next, and so on.   I would appreciate any help on this. Thank you.


A function that maps from A to its power set.

Let $A$ be a non empty set and $f: A \to P(A)$ some function.$P(A)$ is the set of all the subsets of the set $A$. I have to show that $Z_{f} := \{x \in A | x \not\in f(x)\}$ is not in the image of $f$.  I have no idea how to do this, please help. I guess showing that $f$ is not surjective would be one way, since that means it won't take the whole image space but further than that I don't understand..  Thank you in advance


biblatex - issue number of journal in date

I am building a bibliography using biblatex and biber (\usepackage[backend=biber,minnames=2,backref,firstinits,sortcites]{biblatex}) with a lot of cited papers. Therefore I often have the case of a journal name, volume, issue, month and year, all necessary.   Now the strange thing is, if I have a bibitem such as:  @article{item,   title = {Some Nice Scientific Title},   author = {Doe, Jane},   journal = {Important Journal},   volume = {50},   issue = {20},   pages = {1877--1879},   year = {1984},   month = {Jun},   publisher = {Important Society},   doi = {00.0000} }   the bibliography looks like this:    Can you spot it? The issue number 20 is in the brackets with the date. Now it looks like it is the day in the date.  So, how do I get around this?  Here's the full MWE:  \documentclass{scrartcl}  \usepackage[backend=biber,minnames=2,backref,firstinits,sortcites]{biblatex}  \usepackage{filecontents} \begin{filecontents}{item.bib}   @article{item,     title = {Some Nice Scientific Title},     author = {Doe, Jane},     journal = {Important Journal},     volume = {50},     issue = {20},     pages = {1877--1879},     year = {1984},     month = {Jun},     publisher = {Important Society},     doi = {00.0000}   } \end{filecontents}  \addbibresource{item.bib}  \begin{document}  \printbibliography[title = {References},heading=bibintoc] \nocite{*}  \end{document}


The repository does not contain the Release file

When I wanted to update packages I run   sudo apt-get update   but I got this error:  The repository “ disco Release” does not contain the Release file.  How do I fix this?


Portal doesn't look to above the Nether ceiling

I have a problem because I want the nether portal to teleport me to a portal I made on the roof of the nether, and for that I went to the nether, destroyed the nether portal and created the new portal on the roof. and I teleported to where I wanted, but I went back and instead of teleporting to the portal that creates teleport me to a new one Thanks for the help


Famous Question badge on questions with negative scores?

The Famous Question badge is awarded for question with 10.000 views.   I've seen questions with negative scores to be used as a reference to golden Famous Question badges. Why isn't there an additional requirement to have positive score on that question?  Is the intention of this badge to indicate helpful and interesting question or just number of views?


why this program to hide a password doesn't work?

guys i wrote this code to hide a password in input but it doesnt stop printing stars when i press enter i_p = 0; char c_p, password[20]; while((c_p = getch()) != '\n') {     password[i_p] = c_p;     printf("*");     i_p++; }  what's wrong with this code? something in the while condition? i never used conio.h before and i really dont know


What are the meanings of abbreviations used by the users?

Haven't had much luck searching for 'OP' and 'OT' terms in the search box, what does these abbreviations used by users in StackOverflow mean ?


I’m a big fan of ampersands (possibly too much …) and I’d like to replace all mentions of “et al.” (included in citations) by \& al. – both in the main text (I use natbib citations of the form [Author1 et al., 1999]), and in the actual bibliography?  How can I do that, considering that BibTeX is inserting the words for me, and I have no control over the text? Preferably, I’d like to do this without creating my own bibliography style sheet (since I want to make this work regardless of the actual BibTeX style that is used), but if anyone can tell me how I need to edit the style sheet file, that would be fine as well (makebst doesn’t seem to offer an option for this …).


Do I need to report rental income on my apartment?

Say I am renting an apartment for ~$1000 a month and I have a friend that needs a place to say. I let him stay on my couch and he pays me ~$999 a month. So I'm at a loss of $1 each month.  Do I need to report this as income?  He has stayed for more than 14 days (closer to 90), so from my understanding it's not a Tax Free rental. It's also my personal residence, and I'm operating at a net loss because my expense are higher than the revenue it's generating.   Is it considered taxable income because I would be living in the apartment regardless of him needing a place to stay? I'm a bit unclear on how it works if there is not a lease in place. He's just giving me some money each month. And I'm also technically losing money, but I don't want to owe a bunch in taxes later because of a mistake.


How to visit Georgia as a Pakistani citizen?

I am a Pakistani passport holder and I am here in China I want to go to Georgia for visiting. How I can go? How I can get visa?


Irreducible but not prime in $K[X,Y]/(X^2-Y^3)$

I'd like to know why $X+(X^2-Y^3)$ and $Y+(X^2-Y^3)$ are irreducible, but not prime in $K[X,Y]/(X^2-Y^3)$.    I failed in both. For the first, I tried to use an isomorphism $$\phi:K[X,Y]/(X^2-Y^3)\to K[X], a_1=0$$ by $X\to X^3, Y\to X^2$ and for the second I tried to construct a case similar to the factorization $3^2=(2+\sqrt-5)(2-\sqrt-5)$.


Derivation of Euler's equations for rigid body rotation

Sorry for using this image, but I thought this was the most convenient way of asking this question. Please zoom in.  I do not understand from the line, "Now, in the body frame $T = (T_{x'}, T_{y'}, T_{z'})\ldots$"  How is that in the body frame? That should be in the inertial frame, since it is dL/dt. In the body frame, it is dL'/dt.   How can you treat dl/dt as the torque in the body frame, and then derive the Euler's equation?


How do I find the reverse dependency of a package?

I was wondering if it was possible to check what package another package is a dependency of.  For example, jetty is mysteriously installed and running on my system and I'd like to check whether it is a dependency of something else.


Can Excel show a formula and its result simultaneously?

I know that it's possible in Excel to toggle between . I'm required to turn in assignments for a statistics class as a printed Excel sheet showing both the formula and the result. Right now the instructor makes us either copy the formula and paste it as text next to the computed value, or copy the value and paste it next to the formula. This is very inefficient, prone to error (if you change the formula or values after doing the copy-paste), and generally a waste of time.  Is there any way to have Excel show the formula and its value in the same cell? If not, is there any function which will display the formula from a referenced cell as plain text, e.g. =showformula(A1) which would print out =sum(A2:A5)  instead of 25 (if those were the formula and value of cell A1)?  I'm using Excel 2010, but a general answer that works for any recent edition of Excel would be nice.


What does it mean to add a prototype to a function?

Given:  var x = function () {  };   x.prototype = { abc: 25 };   Can someone explain to me what this means. Could this be done all inside a function without the .prototype?  var x = function () {   // something here ? };


Will the Hall of Monuments affect Guild Wars 2 after launch?

Possible Duplicate:          Following on from this question,   Does anyone know if the Hall of Monuments in Guild Wars will affect Guild Wars 2 after release?  For example if I have 34 points now, one short of the title at 35. Can I create a GW2 character, then keep working on my points in GW; beyond the launch of Guild Wars 2 and still reap the rewards in Guild Wars 2?


Integral of $x^{-x}$ from $0$ to infinity $=$ $2$?

Numerical evidence from Wolfram seems to indicate this. Is this just a numerical coincidence, and if not, can someone explain it?  Another interesting, if unrelated numerical coincidence: Wolfram's approximation of the integral of $x^{-x}$ from $0$ to $1$ is the same as its value for the sum of $n^{-n}$ from $1$ to infinity.


How to ignore the underbrace{}{} in a square root?

I want to keep the size of the square root unchanged without putting the underbrace outside     \sqrt{\underbrace{=A}{B}}


is it possible to integrate a chatter news feed from two seperate orgs

the senario is that we want to be able to have a 3rd party supplier share post and info from their SF org with users on our internal SF org.


my phone is stolen and sim cards removed. how to track it?

my android phone got stolen a few hours ago. the thief has already removed both the internet sims.  as such, i had not installed AndroidLost or Mobile Tracker apps in the phone as it is a relatively new one.  i have tried to remotely install it, but it may take time .  please help out with the procedure and suggest methods to get it back.


Can't play VCD and DVD in Ubuntu release 12.04 (Precise) 64-bit

I have tried playing VCDs and DVDs but I always get this type of error:     File reading failed:   VLC could not read the file (Input/output error).


Is it possible to convert an integer to a written out word? IE, convert '29' to 'twentynine'?  There is a comment on the strval() page of the PHP Manual, but it's from 13 years ago, before PHP 5 was introduced. Is there a standard PHP function that can do the same, or maybe an easier way to write out the function?


31 Debian CDs -- Why? and which do I need for a vanilla desktop install?

I've been using Linux (Ubuntu) for a couple of months now, and I want to try Debian to see how different it is.  Well, I've already found a couple of differences..      The first one that Debian-Live means only-Live.   The second difference has stopped me in my tracks. There doesn't seem to be a specific .iso CD to download / install.    I am confronted with a list of 31 CDs ...  debian-506-i386-CD-1.iso -to- debian-506-i386-CD-31.iso   What is this all about and which .iso do I need for a vanilla (32 bit) desktop install?


I know that the L2 regression (regression-based L2 loss function/least square regression) assumptions are as follows.   1- Little or no Multicollinearity between the features.  2- Homoscedasticity Assumption.  3- Normal distribution of error terms.  4- Little or No autocorrelation in the residuals.  My question is, what are the assumptions of L1 regression (regression-based L1 loss function/Mean absolute error?  Any resources/references related to my question are appreciated.


Let us consider the integral $$\int \frac{x^2}{(x\sin x+\cos x)^2}\, dx$$    I have tried with the following way $\displaystyle \int \frac{x^2}{(x\sin x+\cos x)^2}\, dx$ $\displaystyle \Rightarrow \int \frac{x^2\sec^2 x}{(x\tan x+1)^2}\, dx$. How can I do the next step.


Quantum teleportation and no-communication theorem

According to the Wikipedia article for the :     In very rough terms, the theorem describes a situation that is analogous to two people, each with a radio receiver, listening to a common radio station: it is impossible for one of the listeners to use their radio receiver to send messages to the other listener. This analogy is imprecise, because quantum entanglement suggests that perhaps a message could have been conveyed; the theorem replies 'no, this is not possible'.   According to the Jet Propulsion's recent article on quantum teleportation:   they can effect an entangled photon (B) with another photon (A) to change the state of the other entangled photon.  Doesn't this contradict what the no-communication theorem states ?


rotating any Multi-dimensional List without zip function

How can rotate multi-dimensional List without using the zip function, I have this list (but it can be longer):   testlist = [[1, 2, 3],            [4, 5, 6],            [7, 8, 9],            [10,11,12]]   I want to rotate it 90 degrees clockwise and also 90 degrees counterclockwise. ps: The reason i don't want to use zip is because this is a homework and i must write it in vanilla python .


I like make a for loop in bash script with parameters, some like this:  for VALUE in {"$from".."$to"} do       echo -e "Processing $VALUE \n"  done   This no loop, only return: "Processing {1..4}" It is possible?


how to detect the usb stick in Ubuntu installed in virtual box

I have installed Ubuntu 14.04.3 on VirtualBox in Windows 7. How can I detect the USB flash disk in Ubuntu.


In order to combine "nationally" and "top-ranked" would the resulting qualifier be written as "nationally-top-ranked" or "nationally top-ranked"?  Edit: I do not immediately see the applicability of , because that particular question does not address the case of having more than three adjectives that, when written two at a time (two at-a-time?) would be hyphenated (e.g., nationally-ranked, top-ranked).


There was a time before heroin took over Jessica Grubb’s life. “She was an incredible achiever, she made straight-As, she was smart as a whip, involved in social change,” her father said.   What does straight-As mean in the context?  Note:   I have searched straight-As on the QA box, but I didn't find any.  I was not aware that As is the same as A's.  In my native country, we don't have either straight-As or A's classification.


We know that Enoch is a Chronicom, which is to say a sort of alien temporal observer.   When Enoch and his agents came and kidnapped       Coulson’s team,   for the purpose of sending them where they wanted; were these other agents also Chronicoms? I’m inclined to think they must have been (would Enoch have shared their advanced technology and goals, etc. with mere mortals), but on the other hand only one pod was mentioned.


I installed Ubuntu 20.04 yesterday, and it frequently freezes, Everything just stops, but I can move my mouse cursor (Can't click anything though). The only thing I can do is a hard reboot. I don't know if it's the gpu drivers issue, I couldn't find the drivers for my GPU AMD Radeon HD 8750. I'm pretty new to Linux and I could really use some help.


Let A be a subset of R with more than one element, let a in A. If A-{a} is compact.

Let $A$ be a subset of $\mathbb R$ with more than one element, let $a$ in $A$. If $A-\{a\}$ is compact, then   $A$ is compact Every subset of $A$ must be compact $A$ must be finite set $A$ is disconnected   for any open cover of $A$ is also open cover for $A-\{a\}$, since $A-\{a\}$  is compact implies that it has finite sub cover to cover $A-\{a\}$. with this sub cover union an open set containing $a$ will be the finite sub cover for $A$. Hence $A$ is compact  Given that $A-\{a\}$  is compact, so it is closed, this implies $\{a\}$ is open. But every singleton in $\mathbb{R}$ is closed, so $\{a\}$ is both closed and open. Hence A is disconnected   so option (1) and (4) is right.  what can we say about option (2) and (3)?


How to share files from Host to Guest in VirtualBox? Host-Ubuntu, Guest-Ubuntu

I have an Ubuntu 12.04 machine on which I have installed VirtualBox with Ubuntu 12.04 as the guest OS.  How can I share files between the host and guest?   I have installed the guest additions also but still it’s not able to mount the sf_shared folders if even it’s mounted. This means I'm unable to retrieve the file from the host.


Turning a multiple row resultset into columns with multiple rows

I currently have a resultset that looks like this:  Title                   Value Start Time              1998-01-04 01:38:00.000 End Time                1998-01-04 01:43:00.000 Product Name            TESR                                Run Time                325 Delay Time              0 Shutdowns               0 Shift                   2 Gross MSF               3.791682 Start Time              1998-08-12 12:43:00.000 End Time                1998-08-13 16:48:00.000 Product Name            FCC                                Run Time                320 Delay Time              0 Shutdowns               0 Shift                   1 Gross MSF               3.791682 Start Time              1999-11-04 02:43:00.000 End Time                1999-11-04 03:48:00.000 Product Name            1/2" TESR                                Run Time                325 Delay Time              0 Shutdowns               0 Shift                   2 Gross MSF               3.791682   What I would like to end up with is this:  Start Time              1998-01-04 01:38:00.000      1998-08-12 12:43:00.000 End Time                1998-01-04 01:43:00.000      1998-08-13 16:48:00.000 Product Name            TESR                         FCC Run Time                325                          325 Delay Time              0                            0 Shutdowns               0                            0 Shift                   2                            2 Gross MSF               3.791682                     3.121   Basically looking like a spreadsheet with each group of records being put in a column to the right.  The original result is from a pivot of a flat table joined to a sub table that puts a title to the property fields. It is running on SQL Server 2008 R2. The data is coming from an HMI system and the client wants to see the data in the "spreadsheet" format.


I'm trying to implement internationalization in my javaFX project. My idea was to get all the controllers from the other fxml documents and call the method loadLang in each of them when the language is changed. I'm having some trouble though with getting the controllers. Here's my changelanguage method:      @FXML     private void handleChangeLanguage(ActionEvent event) {     FXMLLoader myLoader;     myLoader = new FXMLLoader(getClass().getResource("Ads.fxml"));     AdsController ac = myLoader.<AdsController>getController();     tabPane.getTabs();     if (countryBox.getSelectionModel().getSelectedIndex() == 0) {         loadLang("da");         ac.loadLang("da");     }     if (countryBox.getSelectionModel().getSelectedIndex() == 1) {         ac.loadLang("en");         loadLang("en");     }         //translate them to selected language }     I'm getting a NullPointerException at ac.loadLang("en");. I'm pretty sure it's because it didn't obtain the controller of AdsController.fxml properly. Any ideas?


Error : Bone heat weighting : failed to find solution for one or more bones

With the bones parenting with Ctrl+P. Automatic Weight getting this error.       I have 3 bones only. Removed all the doubles. Applied Rotation Scale. All modifiers applied, All mesh are attached. still there is error. Any suggestion. I tried the manifold option from the 3d print addon still did not work.


What are some good progressions for beginning modeling?

New guy to Blender, want some advice on tutorial projects with small polycounts. So far I have modeled a pawn and a mug.


First material applies but second does not

The first pin material I created is able to get assigned to the whole pin. The second stripe material I can't get assigned to anything.   Blend file:


Topological Vector Space: $\dim Z\text{ finite}\implies Z\text{ closed}$

Let $V$ be a Hausdorff topological vector space and $Z$ a linear subspace: $Z\leq X$  Is there a neat way to prove that: $$\dim Z\text{ finite}\implies Z\text{ closed}$$


Breaking up a file into two parts based on a particular line

I need to breakup a file into two separate files based on a particular line for example:  . . sc_outfifo 0.000E+00 0.000E+00 0.000E+00 0.000E+00 1.586E-02 1.586E-02 1.586E-02 Fub_Level_DACGE(%) PS0_SI.0 PS0_SI.0 PS0_SI.0 PS1_SI.0 PS1_SI.0  siunit 98.91 98.81 98.91 90.06 96.37 81.37 81.37 16655 . .   So all the lines above Fub_Level_DACGE(%) goes in one file and the rest including Fub_Level_DACGE(%) goes in another file. Any idea how it can be done?


Prove among two integers $2^n-1$ and $2^n+1$, at most one is prime.

For any $n>2$, among $2^n-1$ and $2^n+1$, at most one is prime.    I have no clue :(


Theorem 11.14, Apostol, pg 238 - need explanation

An excerpt from Introduction to Analytic Number Theory by Tom M. Apostol.      I have three main concerns regarding this proof:    What is the abscissa of convergence for $\frac{1}{F(s)}$ - why can we take the product of the two series. I only know this is true if the two series are absolutely convergent.  Why can we do term by term integration? I believe its suffices to show that the series converges locally uniformly - BUT is this true?  How does the proof show that $G(s)$ converges uniformly?


Which signal can't be overridden in linux?


How I can find limit of a given problem: $\lim_{n\to\infty}\frac1n[(n+1)(n+2)\dots(n+n)]^{\frac 1n}$?

What is the limit ?  $$\displaystyle\lim_{n\to\infty}\frac{1}{n}[(n+1)(n+2)\dots(n+n)]^{\displaystyle\frac {1} {n}}$$  The given answer is $\displaystyle\frac{4}{e}$, but I don't know how to find it or which formula is applicable here.Please help.  Thanks for  help.


20.04 LTS point release - what bugs are delaying the installation by software updater

I know that 20.04.1 is available to download but my settings are to update "for long-term support versions" and I am currently using 18.04 LTS and I don't get an update. My understanding is that it will be available for updating when all the bugs are ironed out. Is there any way that I can fond out what is delaying the update. It seems an inordinately long delay compared to the time it took for the 16.04 LTS to be updated to 18.04


Ubuntu 1904 does not boot from LiveCD on Hyper-V in AMD Ryzen. No problems in 1804

When booting 1904 LiveCD from a Hyper-V VM, I get some error messages:   Spectre V2:Spectre mitigation: LFENCE not serializing, switching to generic retpoline Couldn't get size: 0x800000000000000e systemd[1]: dev-loop0.device: Failed to set invocation ID for unit: File exists systemd[1]: dm-event.socket: Failed to set invocation ID for unit: File exists   After these errors, the Ubuntu splash screen with the red/white five dots stays forever. This happens for any of the 5 first options in the LiveCD GRUB menu, and the only way to regain control is turning off the VM. When selecting "Check disc for defects", I get the same errors, and then "Check finished: no errors found".  The same VM boots LiveCD 1804.2, installs, updates and runs 1804 without a problem.  I tried allocating more and less processors to the VM, enabling and disabling secure boot, enabling and disabling dynamic memory, without any success.  These problems with 1904 only happen in a new PC I built with a X570 chipset and a Ryzen 5 3600X. On a older PC I had, with an Intel Ivy Bridge 3570k and Z77 chipset, 1904 installed OK in Hyper-V. In both cases, the latest version of Windows fully updated was used.  I suppose Hyper-V there is some kind of incompatibility between Ubuntu 1904 and Hyper-V on Ryzen. Does anybody have a similar problem?  Thank you


Endomorphisms of $\mathbb{H}$ that do not fix $\mathbb{R}$

Are there any nontrivial field endomorphisms of $\mathbb{H}$ that are not the identity map when restricted to $\mathbb{R}$? I realize that the only nontrivial endomorphism on $\mathbb{R}$ is the identity map, so if the desired function $f$ exists, it must be that $f(\mathbb{R}) \ne \mathbb{R}$. Are there any such mappings?


The most relative that I found on Google for de morgan's 3 variable was: (ABC)' = A' + B' + C'.  I didn't find the answer for my question, therefore I'll ask here:  What is De-Morgan's theorem for (A + B + C)'?


Is it possible to add decimals together within a JSP forEach loop?

I am puzzling if it is possible to add decimal values which I get from a stored procedure together and get all decimals within the loop added together as one value.  For example:  <c:forEach var="row" items="${ aStoredProcedure }"> <fmt:formatNumber value="${ row.decimalNumber }"pattern="#,##0.00"/> <br> </c:forEach>   This prints out the values of each decimalNumber of each row onto their own lines in the form of common currency. I need a way to get all these decimalNumbers added together with each other, and I only need the final sum of them all. Can this be accomplished in JSP? any help is appreciated.


What does The Doctor's Speech in The Rings of Akhaten refer to?

I recently watched the brilliant speech from The Rings of Akhaten again. For those who haven't seen it or don't remember it:     I walked away from the last Great Time War. I marked the passing of   the Time Lords. I saw the birth of the universe and I watched as time   ran out, moment by moment, until nothing remained. No time. No space.   Just me. I walked in universes where the laws of physics were devised   by the mind of a mad man. I've watched universes freeze and creations   burn. I've seen things you wouldn't believe. I have lost things you   will never understand. And I know things. Secrets that must never be   told. Knowledge that must never be spoken. Knowledge that will make   parasite gods blaze. So come on, then. Take it! Take it all, baby!   Have it! You have it all!   Some of these I understand:     I walked away from the last Great Time War.    Clear enough     I marked the passing of the Time Lords.   Again makes sense, given he "killed" them.     I saw the birth of the universe and I watched as time ran out, moment by moment, until nothing remained. No time. No space. Just me. I walked in universes where the laws of physics were devised by the mind of a mad man. I've watched universes freeze and creations burn.   I'm very vague on this put is some of it related to The Big Bang?     I've seen things you wouldn't believe. I have lost things you will never understand. And I know things. Secrets that must never be told. Knowledge that must never be spoken. Knowledge that will make parasite gods blaze.   Possibly relating to the question which must never be answered, but at this point we've not been to Trenzalore so does he even know what knowledge is and why?  What do the unknown sections of these speech refer to?


How to enable silent automatic updates for any repository?

I read  how to enable silent automatic updates for Google Chrome. However, I have other repositories like spotify, docky and others for which I would like to enable silent updates.   I am trying to do this in my Ubuntu 10.04 system. But this question applies to all Ubuntu versions. I have the unattended-upgrades package installed.  How can I do this?


Add a section before \tableofcontents to content

Hi I want to add the section of Signature, which is before \tableofcontents, to the Content. Don't know why my codes don't work. Is it even possible? Thanks a lot!  \documentclass[11pt,twoside]{book} \usepackage[top=1.25in, right=1.25in, bottom=1.5in, left=1.75in, headsep=0.5in]{geometry}  \usepackage{amsmath,amssymb,amsthm,mathrsfs,amsfonts} \usepackage{fancyhdr,indentfirst,setspace} \doublespacing \usepackage[round]{natbib} \usepackage[bookmarksnumbered,bookmarksopen]{hyperref}   \renewcommand{\bibname}{References}   \begin{document}  \frontmatter  \title{Test} \author{ABC} \date{\today} \maketitle    \clearpage \pagestyle{plain}  \addcontentsline{toc}{Chapter}{\protect\numberline{}Signature Page}   \begin{center} \vspace{.25in}  Signature  \end{center}      \pdfbookmark{\contentsname}{toc} \tableofcontents    \mainmatter \pagestyle{plain}  \chapter{Inference}  \section{Introduction}   \backmatter  \clearpage \pagestyle{plain} \bibliographystyle{ims} \addcontentsline{toc}{chapter}{References} \bibliography{mybibliography}   \end{document}


Files on my desktop seem to set themselves as hidden files (macOS Catalina), greyed out, even though they don't begin with periods

I have a strange and recurring problem on my recently upgraded Mac running macOS Catalina  First of all, Catalina has a new feature where you can Show/hide the hidden files on your machine using Cmd-Shift-Period. Press it once to show the hidden files press it again to hide them. AFAIK, this specific keystroke feature is new in Catalina (prior to Catalina, I always used the hack to set the finder defaults via the terminal to see my hidden files).  I normally keep my Finder windows showing the hidden files, because I want to see them.  Recently I noticed that all of  my files on the desktop were greyed out-- like hidden. They were just random files I happened to have left on my desktop.  And what's strange is that they don't begin with a period (.), the way normal hidden files do. They seem to behave as hidden files even though they don't begin with a period.  If I press Cmd-Shift-Period, they disappear from view like all of the other hidden files. But unlike the other hidden files, they aren't supposed to be hidden.    If I press Cmd-Shift-Period again, they appear along with the other hidden files in my finder windows    Just to be clear: these files were NOT hidden yesterday, and I didn't do anything that I know of to cause this. And as noted below, it doesn't happen right away when I put new files on the desktop. I noticed it last week too but now it seems to have done it to even more files that I put on the desktop more recently than when I first noticed it (The same behavior-- Finder seems like it took some visible files and turned them into these invisible files without changing the file names or adding pre-pending periods like you'd expect for invisible files.)  1) I'm not sure what is causing this. What could be causing these files to appear in this hidden state and to have been normal files and then somehow get morphed into this hidden state?  2) How can i fix them? I've never seen hidden files like these-- I've only ever seen hidden files that begin with periods (so with this, you can add or remove the period to change its visibility)— if I do "Get Info" on these hidden files I can see the normal Get Info window, which has options for many things like "Hide extension" but no option to set the file to visibile/hidden.  Was this a new feature introduced in Catalina?  When I create new files on the desktop, the new files are not hidden and behave normally:


Show that $8 \mid (a^2-b^2)$ for $a$ and $b$ both odd

If $a,b \in \mathbb{Z}$ and odd, show $8 \mid (a^2-b^2)$.   Let $a=2k+1$ and $b=2j+1$. I tried to get $8\mid (a^2-b^2)$ in to some equivalent form involving congruences and I started with $$a^2\equiv b^2 \mod{8} \Rightarrow 4k^2+4k \equiv 4j^2+4j \mod{8}$$ $$\Rightarrow k^2+k-j^2-j=2m$$ for some $m \in \mathbb{Z}$ but I am not sure this is heading anywhere that I can tell.  Second attempt: Use Euler's Theorem and as $\gcd(a,8)=\gcd(b,8)=1$ and $\phi(8)=4$, $a^4 \equiv b^4 \equiv 1 \mod 8$ so $a^4-b^4\equiv 0 \mod{8}$.  I haven't gotten too much further are there any hints?


If I delete 1 Apple ID (email address) will the same email addy become available to use again?

I have my own AppleID ("Bob") but I don't use this email addy "Bob" anymore. I want to add my current, daily used email addy ("Jim") to my ID, or better yet, make it my only AppleID and delete "Bob". BUT... I already used "Jim" for an AppleID for an older friend who had no email address, so set it up for him on mine, "Jim".  My older friend now has an email address ("Ivan") so can I   add "Ivan" to his AppleID, make it the primary email address, and then delete "Jim" from it? Or... delete his AppleID and create a new one for him "Ivan" knowing he would lose his minor purchases   And most importantly, this would all be pointless unless: - will deleting/removing "Jim" as linked to my friend's AppleID then make "Jim" available for me and no longer registered to another account?


Tried to use my 3TB drive in a USB enclosure, now reports only 746GB even internally

I have two 3TB Hitachi 5k3000 Desktar drives that I want to use as data drives, not boot drives. When I was originally trying to install them I wanted to mirror them using my hardware raid but I couldn't get them recognized, my motherboard is pretty old (P5N32-SLI) but the BIOS and RAID firmware are as up to date as possible.   Whilst trying to get the drives recognized I found you need to initialize them to GPT to see past the 2.2TB barrier, I tried initializing one in Windows (7 x64) via a USB drive enclosure and even though it was set to GPT it never reported the correct size only 746GB.   Next, I tried initializing the other disk connected via the internal SATA ports on my motherboard and it actually reported the correct size (in MBR mode it reported 2.2TB and 746GB, when I switched to GPT it showed one continuous volume.) However, now I can't get my other one to reinitialize, I tried switching it back to MBR but that did not make a difference. I suspect Windows is caching something about this drive that I'm not seeing, but would greatly appreciate some guidance.  Edit: I don't want to use these with my USB enclosure, I want them internal. One drive does work as expected internally, just the one I originally tried to initialize via the enclosure won't re-initialize internally with the correct space.


Can you pickup just the wild card on frozen pile in canasta?

If the player before you in canasta freezes the pile with a wild card, can you pick the pile up if you have two wild cards in you hand? Do you have to take the entire pile or just the wild card on top?


What is the difference between ls and ls -l?

I am very new to linux. While practicing the file management commands I have found that 'ls' and 'ls -l' gives 2 different outputs but they appears to be related to each other.     The content of the file hello.sh is echo "Hello world"  can anyone explain what does 'ls -l' gives as output.


Why is there no defined constant literal for shorts

In the list of constants:   '\0' char true, false boolean 2U unsigned / unsigned int 2 int 2L long 2.0 double 2.0f float "" string 0x0 hexadecimal integer 02 octal integer 1E-8 exponential     I see primarily all the constants corresponding to their standard data type or interpretation value. However I don't see a specific for (short / short integer / 2 bytes / word / int16). Is there any particular, reasonable argument for its absence ?


How can I write the name show in axis of 3D array using TiKz

I am drawing a 3D array like the attached picture, which actually describes a multidimensional array. However, I can not put the name of the axis and take the value from the matrix like the attached picture.  This is the code that I have:  \documentclass[margin=5mm]{standalone} \usepackage{tikz} \usetikzlibrary{matrix,calc}  \begin{document} \begin{tikzpicture}[every node/.style={anchor=north east,fill=white,minimum width=1.4cm,minimum height=7mm}] \matrix (mA) [draw,matrix of math nodes] { (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ };  \matrix (mB) [draw,matrix of math nodes] at ($(mA.south west)+(1.5,0.7)$) { (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ };  \matrix (mC) [draw,matrix of math nodes] at ($(mB.south west)+(1.5,0.7)$) { (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\ };  \draw[dashed](mA.north east)--(mC.north east); \draw[dashed](mA.north west)--(mC.north west); \draw[dashed](mA.south east)--(mC.south east); \end{tikzpicture}   \end{document}


How does this code properly return its value?

The exercise wants you to make a function that will take an integer and go through adding up its total - 1 each time, so i.e. 4 would be 4 + 3 + 2 + 1 = 10 function addUp(num) {   if (num === 1) return 1;   return num + addUp(num - 1); }  This works, but I'm not sure how. If I used say 6 to me the return line would be 6 + 5 = 11; I'm not sure how this looping? Thanks


Error when attempting to convert png to pdf

I did sudo. What else needs to happen? $ sudo convert 386-x.png 386-x.pdf [sudo] password:  convert-im6.q16: attempt to perform an operation not allowed by the security policy `PDF' @ error/constitute.c/IsCoderAuthorized/408.


The dimension of $X$ as an affine variety is the same as the dimension as a vector space?

Let $X \subset \mathbb A^n$ be an affine variety that is also a vector space. In my algebraic geometry course we have seen that $X$ is a noetherian topological space so we can define the dimension of $X$ as the supremum over all $n \in \mathbb N$ such that there is a chain $$\varnothing \subsetneq Y_1 \subsetneq Y_2 \subsetneq \ldots \subsetneq Y_n \subseteq X$$ of length $n$ of irreducible closed subsets $Y_1, \ldots, Y_n$ of $X$. What is the link between this notion of dimension and the dimension of $X$ as a vector space ? It seems that they are equals, because we can always construct a chain like $$\{0\} \subsetneq \text{Vect }(\{e_1\}) \subsetneq \text{Vect }(\{e_1, e_2\}) \subsetneq \ldots \subsetneq \text{Vect }(\{e_1, \ldots, e_n\}) = X,$$ but I am not able to write a rigourous argument. Any help?


Hello again Ubuntu users  I'm trying some new things with mkdir and I can't quite get the hang of things  I want to learn how to make a directory inside of a specified path, then a touch.txt text document with words inside or a story  So far I've got   mkdir ~/Desktop/new_file touch ~/Desktop/new_file/adas.txt   But that doesn't work, and not sure how to get words in it all from one command line


Prove sequence $a_n=n^{1/n}$ is convergent

How to prove that the sequence $a_n=n^{1/n}$ is convergent using definition of convergence?


The Schwarzschild radius involves an expression in terms of Newton's constant $G$, the mass $M$ inside a radius $r$, and the speed of light squared $c^2$. Current estimates of the universe's matter density are about six protons per cubic meter.  But, the $M$ inside a sphere goes up as $r^3$, while the "time curvature" coefficient is $1 - \frac{2GM}{c^2\, r}$.  So this coefficient is bound to hit zero for $r$ large enough.  The $M$ outruns the denominator as a function of $r$.  I calculated that this coefficient hits zero when $r$ equals 13.54 billion light years.  Question:  Is this any evidence for our universe being one very large black hole?


XML commet for return collection of type T

I would like specify in XML comments that method return collection of IEnumerable<FileInfo>.  What is  correct format for XML tag <returns/>.  /// <summary> /// Extensions methods for class <see cref="System.IO.DirectoryInfo"/> /// </summary> public static class DirectoryInfoExtension {     /// <summary>     /// Load files from folder     /// </summary>     /// <param name="dir">Folder</param>     /// <param name="searchOption">search options</param>     /// <param name="extensions">types of files</param>     /// <returns>Collection of <see cref="IEnumerable{FileInfo}"/></returns>     public static IEnumerable<FileInfo> ByExtensions(this DirectoryInfo dir,         SearchOption searchOption, params string[] extensions)     {     }


It is common in machine learning papers to see notation such as   $$X \in \mathcal{X}$$  where both variables are "X" but one is in calligraphy (\mathcal in typesetting).  When reading a document using such notation, the difference between variables is obvious, but orally "X in X" may be confusing to some listeners.    Is there a standard (or even common) parlance/notation used to refer to calligraphic letters orally?


How to count the number of unique views of a node?

Is there any possible way to find the number of views of a node.  For example:  I have created a node called "Sample".  If i viewed it once then the count should be increased as 1 view and when i view the same node again it should not get increased.  Is there any module to do that..   Else what's the best way to do it ?


What is the proper name for a circle with a line through it?

What is the formal name for a circle with a line through it (often red in color) indicating that something behind the line is "off-limits"?    For example, this sign indicating that one should not touch:


Given $A$ is a nonsingular $3\times3$ matrix prove that if $AA^T=I$ then it is not necessary that $A^TA=I.$  Ie show shat for a matrix to be orthogonal its necessary that both $AA^T=I$ and $A^TA=I.$  Attempts- i tried to use variables for A but could not do it. As a habit if i take A^-1 =AT then the solution becomes wrong.


Store name appears twice in meta titles while searching in Google?

In Google,   While searching my (Magento) site, the meta title appears twice.  I am new to Magento, and don't know why it's appearing twice.


Why is my density plot just a line on the bottom?

Basically, I'm just trying to plot a curve over my histogram for the weight of a few students.   lines(density(weight), lwd = 2, col = "red")   However, what I get is a line on the bottom of the graph. I suppose the density has to be such that the integral of the curve is 1. What command should I be using instead of density, if I want to have a fitting curve for the histogram?


Positioning of comma when assumptions are added to other people's information, as in "I assume"

In a passage of my book, a character tells another that he's "dead". Now, this scene is quite intense, propping up what seems like an imminent fight. The character being threatened has picked up on this, and asks a question in return regarding the information given, with an assumption added. My question is where the  comma should come.   Here are the two alternatives (as I see it):     But tell me Gussy, how do you intend to support this claim of my, I assume, imminent death?   Or number two:      But tell me Gussy, how do you intend to support this claim of my, I assume imminent, death?   The first alternative feels much more natural, especially considering how I'd say it. But the second one feels like it makes more sense. I feel it makes more sense because his assumption is the imminence, and not the "death" part. Though, this is quite obvious, considering the "death" part has already been explicitly stated. The imminence on the other hand, is strongly implied. Yet, the first alternative still feels syntactically wrong (if it even relates to syntax). But the first one is also the one that feels the most natural to write. Also, separating the sole adjective of a noun with a comma seems weird.   So, which alternative is correct? If both, which is most common and/or grammatical (if grammaticality is even a factor in such a case)?   EDIT: If I have understood the comments correctly, people are telling me that an alternative could be:      But tell me Gussy, how do you intend to support this claim of my (I assume, imminent) death   That alternative might be a misunderstanding of what the commenters were trying to communicate, but I guess that'll be revealed soon enough.


My girlfriend owns a D5100 and I own a D7000 for which we both share lenses (or try to when appropriate). I own the 18-55 kit lens, a Nikkor 50mm 1.8g (I may consider buying the inexpensive 50mm 1.8d so that we can both have the 50mm at all times) and a cheap Sigma 70-300 4.5-5.6.  As of right now, I do 65% of my shots using the 50mm, including, most of the time, landscape photography. I just adjust the composition by adjusting my position and only use the kit lens when that's not an option. For some time I've been thinking about acquiring a wide angle lens, but after checking up the prices and different models I couldn't make up my mind.  What is it that you look for in a wide angle lens?  To make it easier to explain where my doubts lay, let's say the Nikkor 24mm 2.8D which sells on amazon for 360 pounds / $450.   Do I really need a fast lens for landscape? I mean, 90% of my shooting with a wide lens is going to be architecture or landscape so why would I need a fast lens? Most of my photography (which tends to be street photography and portraits) is taken with the 50mm or the telephoto (which I'm seriously considering upgrading to something not crappy)... are there other usages for wide angle (other than landscape and architecture) that I'm missing? (I mean things you'll do often, not things that you may do but you never end up really doing). How is it different from the kit lens? I can deduce build quality of the kit lens is not going to be great, but it's still a 18mm f3.5 in the wide side, so wider and reasonably fast... is it really worth it to get the Nikkor 24mm? Why?


Installing Windows (10?) for dual boot on Ubuntu PC

I have a PC running Ubuntu 14.04, and I wanted to install Windows as well, for gaming purposes. I've read that it's safer to install Windows first, but it's too late for that, so I wanted to partition my drive to add Windows 10. How can I do this safely? If there isn't a way to do so, should I use two hard drives instead?


I have a toy for my son, it's great but it flies round and round in the dark,  I was thinking of sticking an LED on it like we used to do at school - back then LED's were rubbish but they had long legs and were designed for electronics and soldering - I am 43 now - but I remember we had to calculate the resistance put in a resistor and then it wouldn't blow the LED .. we made a fuse tester back then..  since then LED's have changed markedly.. but is there still a "brand/family" of LED .. a single stand LED... that will plug straight into a 1.5v AA without blowing that comes with REALLY long wire legs so I can solder it direct to the terminals of the AA battery in series, and fit it into the battery enclosure simply by putting the battery cover on top of it? and do they still come with thin stiff wire long metal legs that can be bent, hold a shape and remain put?  OR. If I need a resister in series what is the resistor I need can someone help me calculate?  and also, they are still a diode, are they forgiving of the polarity or will they blow if placed the wrong way round?


How to Tail -f output with colors using only Awk and show the rest of the output?

I was able to do a tail -f output with colors using the awk command. But I'm unsure how to output the rest of the log as it seems to be filtering only those 2 lines. I also want to see the other lines as the log is written.  What do I need to put in the awk command to show the rest of the output?  Image of my issue. The red text above is without using awk and displays the entire tail -f log. And below that is the same command with the awk color filtering.


proving that the if $s_{n} \leq t_{n}$ for $n\geq N$ $\liminf_{n\to \infty} s_{n} \leq \liminf_{n \to \infty}t_{n}$

Using Danny Pak-Keung Chan's answer I've tried to do the supremum case. We want to show if $s_{n} \leq t_{n}$ then $\limsup s_{n} \leq \limsup t_{n}$ Let $n\geq N$ be arbitrary and let $k \geq N$ be arbitrary. Then $s_{k} \leq t_{k} \leq \sup_{m \geq n}t_{m}$. Thus $\sup_{m \geq n}t_{m}$ is an upper bound of the set $\{s_{n}, s_{n+1}, \dots ,\}$ therefore $\sup_{m \geq n}t_{m} \geq \sup_{m \geq n}s_{m}$. Define $S_{n}:= \sup_{m \geq n}s_{m}$ and $T_{n}:= \sup_{m \geq n}t_{m}$. Then we have $S_{n}$ and $T_{n}$ are decreasing. Hence $S_{n} \leq T_{n}$. Therefore $\lim_{n \to \infty}S_{n} \leq \lim_{n \to \infty}T_{n}$. Hence $\limsup s_{n} \leq \limsup t_{n}$


Is there any mathematical meaning to words like: Event or Cause or Effect etc

If you read any text on Physics then you would reorganize after enough time that  Yes language of physics (Nature) is mathematics. I'm letting this discussion to opinion-based nor some philosophy of science. So when I say the word energy I know How do I say the same thing mathematically or velocity or position etc. But I found some of the words that play a central role but I didn't found any mathematical words to describe them Like in special relativity.  A reference frame is a way of labeling each event with its location in space and the time at which it occurs.  I'm here concern with the word event. What do we mean by an event? The emission of the photon is an event, the transition of an electron is an event, electron kick out of the atom is an event. If there is a thing, there is an event. The example seems plausible, but How do we define an event (Mathematically if possible)? I have a similar problem with the word cause and effect. See the following sentence.  To be able to make sense of cause and effect, only events in our past can influence us, and we can influence only events in our future.  This doesn't make sense to me what we mean by influence. I know what it meant in a daily sense, If a bullet gets through me, it's going to influence me, But really I don't get it mathematically when do I say something influencing me. Can anyone help me through this?


Python equivalent of Java Regex Quotation

EDIT: As already explained in the original question, re.escape() is not a solution for this use case. This is therefore not a duplicate of . Please read the question before closing as a duplicate!  Java allows the use of \Q and \E to escape blocks of characters, instead of only escaping characters one at a time. .  Is there an equivalent for this in Python? I've reviewed the  and couldn't find it, but I want to make sure I'm not missing something.  I know there's re.escape() which will automatically escape all non-ASCII characters, but this doesn't work for my use case.  My use case is effectively taking a user-supplied string of format foobarbaz<c> and turning it into a regex that will match foo followed by a number then bar then another number then baz then another number. It would then capture the values of , , and <c>. Also, it's possible that foo, bar and baz could instead be strings containing regex special characters, such as in the case of $.cities[].name.  Java code is something like this:  String key = "foobarbaz<c>";  String keyRegex = "^\\Q" + key + "\\E$"; Matcher m = Pattern.compile("<.*?>").matcher(key);  while (m.find()) {     keyRegex = keyRegex.replace(m.group(), "\\E([0-9]+)\\Q"); }  keyPattern = Pattern.compile(keyRegex);


Regular Expression to split on spaces unless in quotes

I would like to use the .Net Regex.Split method to split this input string into an array. It must split on whitespace unless it is enclosed in a quote.  Input:  Here is "my string"    it has "six  matches"  Expected output:   Here is my string it has six  matches   What pattern do I need? Also do I need to specify any RegexOptions?


How do I enter a file or directory name containing spaces or special characters in the terminal?

I have a collection of files and directories with strange names, they contain spaces and the special characters \, *, ), ( and ?. All of them cause problems when I try to use them in the command line or scripts, e.g.:    $ cd space dir bash: cd: space: No such file or directory  $ cat space file cat: space: No such file or directory cat: file: No such file or directory  $ cat ( bash: syntax error near unexpected token `newline'  $ echo content >\ > ^C  $ ls ? (  )  *  ?  \   How do I enter file or directory names that contain special characters in the terminal?


Is "shift & add" technique valid for infinite sequences?

The "shift & add" technique is an excellent trick to get standard formulas for summation of various finite sequences. e.g.  (Newbie here, couldn't get the aligning proper, so stuck to special case $n=5$) $$ \begin{aligned} 1-2+3-4+5&=S\\ 1-2+3-4&=S-5 \end{aligned} $$ And, we could add up & get the results/formula accordingly. ($\sum_{k=1}^\infty(-1)^{k-1}k=\frac{1}{2}$)   But, is this trick suitable or correct when dealing with infinite sequences? e.g. $$ \begin{aligned} 1-2+3-4+5-\cdots&=S\\ 1-2+3-4+\cdots&=S \end{aligned} $$ The professor then adds up!? (isn't the result off by infinity?!) If this is correct, the source link result is quite astounding indeed, what more mathematical implications does it have?  Source -


I have 2 tables (assume ID is the key) and used nested loop in my codes and it worked fine.  select * from table1 where table1.ID in  (select ID from table2 where status='ACTIVE')   The SQL above could be converted to Linq as below:  from a in table1 join b in table2 on a.ID == b.ID where b.status="ACTIVE" select a;   But now what I am looking for is the other half of the result.   select * from table1 where table1.ID NOT in  (select ID from table2 where status='ACTIVE')   Please note the "NOT" in the statement above.    Can any one help?


Is the 50% loss of energy when charging a cap from a battery a set rule in stone?

This question is similar to  (And no it is not a duplicate it is different in that it has been made more clearer.)  What seemingly was originally thought as an extremely easy question was not well understood. So it has been reworded again to be even more specific. So not a duplicate question.  It is meant to be understood that a capacitor starts with 0J and 0V in it. Next the switch is closed in order to connect the battery to the capacitor in order to charge it up to the exact same voltage level of that of the battery.   There is now 7.2 milliJoules of energy stored in the capacitor.    I am only referring to the schematic presented, which works exactly like what the schematic portrays. This is a real world circuit done on the work bench. It has losses due to resistance in the wires, capacitor, battery, and switch.  It is not lossless and so it is not perfect, there are losses involved as mentioned immediately above.  Half the energy is lost in doing work to transfer the other half into the capacitor. In other words the amount of work it takes to transfer half the energy into the capacitor is exactly equal to the amount of energy stored in the capacitor. This is a well known fact of life and electronics.  In other words, if 2 Joules of energy came out of a battery, then only 1 of those Joules would make it into the capacitor.  What I am asking is: When charging a capacitor from a battery, is this 50% loss of energy and 50% stored energy in the capacitor a set rule in stone?  I am referring to this exact circuit only or any other similar circuit with different capacitance's or different battery voltages with the exact same process of simply closing the switch just one time only.   I am not referring to ramp charging, step charging, or anything other type of charging. No other components are involved or added into the circuit. Just a simple closing of a switch to connect the battery to the capacitor only.  I know that this is another question but it's directly related to the first question, I don't want to ask it in another question and risk having a duplicate question, which it shouldn't anyways.  Other question: If the 50% loss of energy in order to transfer the other 50% energy is a set rule in stone then what voltage would the capacitor have to be in order to double the energy in the capacitor to make it equal to 100%?  In other words, what voltage should the capacitor be when it has 14.4mJ of energy in it, which should be double or twice the amount of the 50%, if I am getting that correct at all.  It should not be inferred that I am implying that the capacitor is capable of receiving 100% of the energy transferred from the battery as this is completely impossible and preposterous with the given circuit, but only asking what voltage would the capacitor have to be in order to double the 50% of the energy transferred into it?


What is Chrome Canary and how is it different from Google Chrome?

As the question title says it all, I read Google support, I read few things here and there, the only thing they say is it's for developers and it is updated at a rapid speed, but how exactly is Chrome Canary different from Google Chrome?


How to count the number of elements present in a JSON object?

I have a PHP/JSON as show below. JSON: {"posts_id_en":"101, 102, 103","posts_id_fr":"", "reports_id_en":"101, 102", "reports_id_fr":"101"}  PHP code: echo count(explode(",", $data->posts_id_en));    //  Line A  (3)  echo count(explode(",", $data->posts_id_fr));    // Line B   (1)  echo count(explode(",", $data->reports_id_en));    // Line C  (2)  echo count(explode(",", $data->reports_id_fr));    // Line D  (1)  Line A php code, Line C php code and Line D php code print 3, 2, and 1. Problem Statement: I am wondering what changes I need to make in the php code above at Line B so that it prints 0 as there are no elements inside posts_id_fr


I realize I must earn privileges to participate, but how can I approach the situation below calmly and formulate the full answer when I get this type of response:  A Recent post from SuperUser.  See .     I don't have 50 rep yet so I can't add a comment, but it looks as if you may need 1 more library. Does this link help?   To which I received a comment:           I'll convert this to a comment, but this is an exception.. please answer questions where you don't need additional info first, until you have 50 reputation. Then you're free to comment everywhere. Thanks –  slhck♦ 2 hours ago   While that may be the rule that rather rude response makes me want to stay away from that exchange portal, which is the opposite approach I want to take.  What is the correct method for new users to help with questions when a new user hasn't earned all the tools?


How do I change player name in Minecraft smp in offline mode on a Mac?

This post pretty much summarizes my question :   I know for a fact that Mac and Linux are both Unix based  And the commands for Linux should work for Mac, but with limited knowledge for programming I couldn't get it to work.  EDIT: Just saw this -  currently working on it


Provide an easier way to find the meta of each Stack Exchange site

I could not find the meta of Web Applications. It should have been easier to find (I did not find it actually, I just added "meta" to the URL).


How can I split a url string up into separate parts in Python?

I decided that I'll learn python tonight :) I know C pretty well (wrote an OS in it) so I'm not a noob in programming so everything in python seems pretty easy, but I don't know how to solve this problem : let's say I have this address:    Now how can I create two strings from this, one containing the "base" name of the server, so in this example it would be   and another containing the thing without the last filename, so in this example it would be   . Also I of course know the possibility to just find the 3rd and last slash respectively but maybe you know a better way :] Also it would be cool to have the trailing slash in both cases but I don't care since it can be added easily. So anyone has a good, fast, effective solution for this? Or is there only "my" solution, finding the slashes?  Thanks!


What's wrong with this object declaration?

#include <iostream> using namespace std;  class A {     public:         int x;     A() {         x=1;         cout << x <<endl;     } };  int main() {     A b();     cout << b.x << endl;     return 0; }   Running this results in compilation error: Error: request for member 'x' in 'b', which is of non-class type 'A()' "cout<< b.x <


I am to prove that the variation of Dirichlet's function is infinite. I would really appreciate any help, because I do not know how to start. $$f(x)= \begin{cases} 1  & \text{if $x\in\mathbb{Q}$}\\ 0 & \text{if $ x \notin\mathbb{Q}$} \\ \end{cases}$$


I will have a connecting flight in Dubai going to UK and vice versa when coming back here in the Philippines. I am wondering if I still need to get a visa when I am only staying in the airport to wait for my next plane for about 4-5 hours only.


How can I suppress a "bubble" from Beamer heading using Frankfurt template?

Is there some way to repress creation of a bubble displayed in the Frankfurt progress header for specific frames?  In the example below, when compiled it will show four bubbles on the top of the ticker.  Instead I'd like for there to only be two bubbles one for Slide 1 and another for Slide 2a, but to suppress bubbles for slides 2b and 2c.  \documentclass[pdf]{beamer} \mode<presentation>{\usetheme{Frankfurt}} \begin{document} \section{Intro}  \subsection{} \begin{frame}{Slide1}     Text \end{frame}  \subsection{} \begin{frame}{Slide2a}     Image \end{frame}  \subsection{} \begin{frame}{Slide2b}     Image \end{frame}  \subsection{} \begin{frame}{Slide2c}      Image \end{frame}  \end{document}


Difference between 'DateTime' and 'DateTimeOffset'

What is difference between a DateTime and a DateTimeOffset object?   And when should we use each one?   In a web-application that may change the server's area, storing date and time.  Which one is better, or is there any other suggestions?


to open send to folder in windows 7, we type  shell:sendto  and to open apps folder in windows 8, we type  shell:appsfolder  first of all, i would like to know what is this syntax known as (shell: something)  secondly, if anybody can tell me, please give the complete list of commands similar to this  thanks Gagan


My C hard drive is full and i don't know the reason why . I've moved all important files such as download folder and document folder to another hard drive (in my case , i moved it to D: drive) . I've also uninstalled apps and reinstalled them at another hard drive . My program files + program files (x86) is less than 10 gb and my C drive max capacity is 95 GB . I need to clean my C: drive but i don't know what to delete anymore , can someone give me clue what causes the hard drive to become full and what should i clean ? For my case , my OS is windows 8 . Just saying in case that OS has something to do with the hard drive being full.


template with multiple post loops for multiple widgets

I have two different widgets on one of my pages. They both display posts, but from different categories. One widget has pagination. Now when I switch to another page, the 2nd widget doesn't display anything. I suppose this is due to some pre-filtering done on the new page, resulting in no posts of the 2nd widget's target category being in the post list. Like e.g. all posts from the 2nd widget's category would be on page 1, so they are not available on page 2 since the post query/fetch WP does ahead of loading my page has already skipped them.


How can I capitalize the first letter of each word in a string in Perl?

What is the easiest way to capitalize the first letter in each word of a string?


As the title suggests, I'm asked to describe the Galois group of the polynomial $x^4 - 5x^2 + 6 \in \mathbb{Q}[x]$ over $\mathbb{Q}$.  I am pretty certain I have 95% of the problem completed. I'm just having difficulty fully putting together the last step (I think it may boil down to a lack of knowledge in the "types" of groups).  The roots of this polynomial are $\pm \sqrt{2}$ and $\pm \sqrt{3}$. The automorphisms are thus: $$f_1(a + b\sqrt{2}) = a - b\sqrt{2} \\ f_2(a - b\sqrt{3}) = a - b\sqrt{3}$$  This resembles... something like... a group $\{e, \sigma_1, \sigma_2\}$ that has two coordinates? Something like $\sigma_1 \times \sigma_2$ where $\sigma_1$ cycles between itself and its negative and $\sigma_2$ cycles between itself and its negative.   I feel like there's just one little thing I'm missing.   (Edit: I think I've got it. This group is isomorphic to $\mathbb{Z}_2 \times \mathbb{Z}_2$, right?)


is there any difference between these two words?  I understand that people often use "food waste" to talk about the issue of throwing away too many cooked food  However, it seems to me that it would be more accurate to describe it as "food wastage".  Another interesting point is about an implicit connotation.     Dictionary.com states that: Waste and wastage are to some extent interchangeable, but many people think that wastage should not be used to refer to loss resulting from human carelessness, inefficiency, etc: a waste (not a wastage) of time/money/effort etc   however, when I refer to another book or, such connotation is not acknowledged.     the Guide to English Usage states that: wastage = act or process of wasting; whereas waste  = unused remnant.   Can anyone explain to me the difference regarding the two words?


Fix the regex to support the email examples in wiki using javascript?

i am using the regex below to validate email const regex = /[a-z0-9!#$%&'*+/=?^_{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?/;  i am trying to validate all the emails in the wiki here  the above regex works for all except the below valid emails are invalid and invalid emails are tested valid. valid strings "john..doe"@example.org " "@example.org admin@mailserver1     invalid strings A@b@c@example.com a"b(c)d,e:f;g<h>i[j\k]l@example.com just"not"right@example.com  how can i fix the regex to work for these too. could someone help me fix this regex? thanks. EDIT what i have tried based on answer provided const regex = (?:[a-z0-9!#$%&'+/=?^_{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_{|}~-]+)|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\[\x01-\x09\x0b\x0c\x0e-\x7f])")@(?:(?:a-z0-9?.)+a-z0-9?|[(?:(?:(2(5[0-5]|[0-4][0-9])|1[0-9][0-9]|[1-9]?[0-9])).){3}(?:(2(5[0-5]|[0-4][0-9])|1[0-9][0-9]|[1-9]?[0-9])|[a-z0-9-][a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]|\[\x01-\x09\x0b\x0c\x0e-\x7f])+)]); but gives me error expression expected at here (? starting of expression


By default, Trello adds the newest attachment to the top of a stack. Short of deleting all attachments on a card and re-adding them in the order I require, is there any other way to sort them?


Relativity and speed of light again - two opposite light sources

Two light sources emit light at the same moment but in opposite directions. At what speed the distance between two light fronts is increasing? c or c * 2?  Note, that there is only one coordinate system here - a system, where these two light sources are placed and they don't move.


This is a simple experiment that anyone can do at home. Open your tap so that the water maintains a laminar flow, and the cross section of flow is considerably thin. Place your finger 3-4 cm below the flow. A beautiful wave-like pattern is observed on surface of flowing water, near the region of your finger. Changing the position of finger changes the 'wave-length' of the wave.   The attached picture shows how to do this experiment, though the resolution is not clear.    What is the explanation for this phenomena? Probably a harder question would be if there is an intuitive explanation for it. Thanks!      ${\bf Edit:}$ I observed a similar phenomena in the swimming pool...when the water is still, move your hand slowly along the surface of the water. It causes a 'bump' in the water, which decays away in a wave-like pattern in front of your hand. Clearly they are the same phenomena: water falling on the hand or hand moving against the water.  The answers below are very interesting (Thanks!). And as far as I can see, they are still being debated, suggesting that the phenomena is more non-trivial that it appears to be. I had accepted an answer earlier, but I am now taking it back, as I did not completely understand it. Looking forward to further discussion on it. It would be most exciting to find an answer that is elementary: without resorting to complex terminologies of fluid mechanics.


How do I extract lines from one file containing a list of words from another file?

I've tried all the suggestions on this website and the output is incomplete. File 1 showing list of proteins I'd like to search in file 2 and extract the complete set of lines containing the information I need. Q14157 Q14444 P23246 Q96EP5 Q9UN86 Q14011 Q7Z739 Q9Y383 Q96I24 Q9NP61 P29558 P51116 P00441 Q2TBT7 Q9NZI8  File 2 containing (incomplete paste here on this section) the info to be extracted from the list in file 1. P21796  260 Phosphoserine   S   1 P21796  266 N6-acetyllysine K   4 P21796  266 Ubiquitination  K   3 P21796  274 N6-acetyllysine K   1 P21796  274 Ubiquitination  K   3 P18848  45  Sumoylation K   1 P18848  45  Ubiquitination  K   2 P18848  53  Sumoylation K   1 P18848  55  Ubiquitination  K   2 P18848  69  Phosphoserine   S   4 P18848  75  Ubiquitination  K   2 P18848  88  Ubiquitination  K   2 P18848  107 Phosphothreonine    T   1 P18848  114 Phosphothreonine    T   1 P18848  115 Phosphothreonine    T   1 P18848  119 Phosphothreonine    T   1 P18848  213 Phosphothreonine    T   1 P18848  215 Phosphoserine   S   1 P18848  219 Phosphoserine   S   4 P18848  224 Phosphoserine   S   3 P18848  231 Phosphoserine   S   1 P18848  235 Phosphoserine   S   1 P18848  245 Phosphoserine   S   3 P18848  248 Phosphoserine   S   3 P18848  267 Sumoylation K   1 P18848  277 Ubiquitination  K   1 P18848  293 Phosphothreonine    T   1 P18848  295 Phosphotyrosine Y   1 P18848  335 Ubiquitination  K   2 P18848  343 N6-acetyllysine K   1 P18848  348 N6-acetyllysine K   1 P23246  7   Dimethylation   R   1 P23246  7   Omega-N-methylarginine  R   2 P23246  8   Phosphoserine   S   3 P23246  9   Asymmetric dimethylarginine R   1 P23246  9   Dimethylation   R   1 P23246  9   Methylation R   1 P23246  9   Omega-N-methylarginine  R   3 P23246  19  Dimethylation   R   1 P23246  19  Methylation R   1 P23246  19  Omega-N-methylarginine  R   2 P23246  25  Dimethylation   R   1 P23246  25  Methylation R   1 P23246  25  Omega-N-methylarginine  R   2 P23246  32  Dimethylation   R   1 P23246  32  Methylation R   1 P23246  33  Phosphoserine   S   8 Q14011  17  Phosphothreonine    T   1 Q14011  21  Phosphoserine   S   1 Q14011  33  Phosphoserine   S   1 Q14011  47  Methylation R   1 Q14011  71  Phosphoserine   S   3 Q14011  84  Ubiquitination  K   2 Q14011  94  Dimethylation   R   1


Ubuntu 17.04 - Where is file /etc/default/rcS?

I'm trying to fix a date&time problem in my Ubuntu 17.04 but I cant't find mentioned file /etc/default/rcS. I find only this path /etc/rcS.d but I think it has nothing to do with UTC default setting. I'm looking for option UTC=yes/no.


Asking nature a single question or a carefully thought out questionnaire

In The Seven Pillars of Statistical Wisdom book by  Stephen M. Stigler:     William Stanley Jevons, writing in his Principles of Science in 1874:      One of the most requisite precautions in experimentation is to vary   only one circumstance at a time, and to maintain all other   circumstances rigidly unchanged.      Ronald A. Fisher, writing in 1926:      No aphorism is more frequently repeated in connection with field   trials, than that we must ask Nature few questions, or, ideally, one   question, at a time. The writer [Fisher] is convinced that this view   is wholly mistaken. Nature, he suggests, will best respond to a   logical and carefully thought out questionnaire; indeed, if we ask her   a single question, she will often refuse to answer until some other   topic has been discussed.   I continued to finish the book and yet can't understand, what was the insight Fisher got. When googling for an answer it seems the former idea (keep everything fixed and change one thing aka ) is the recommended approach.  What is the insight Fisher is talking about?


different zoom level for same shapefile arcmap

I have a road Shapefile in ArcMap which includes three different type of roads highway, motorway, streets. I want to display all these roads at different scale. One way to do this is to create three new shapefiles and set zoom level for each of these but this is not what i want. I heared that ArcMap modelbuilder can do this but can't find any help.


Black screen while installing on a HP Pavillion 15

I'm asking for help installing Ubuntu 64bits on a HP Pavillion 15 through USB.   Disabled Fast-boot Disabled Secure Boot Prioritized USB boot   So I boot into GRUB I select either run or install and I get a black screen. If I select Try Ubuntu I have the Ubuntu loading screen then I get a black screen.  I've tried to Enable Legacy support and prioritize USB (something about if legacy is enabled UEFI is still prioritized) and I still have no luck.


Lower bound for denominator of $\displaystyle \frac {a_1}{b_1} + \frac {a_2}{b_2}$ in terms of $b_1$ and $b_2$.

Let $a_1, a_2, b_1, b_2$ be positive integers such that $\gcd(a_1, b_1) = \gcd(a_2, b_2) = 1$. It appears to me based on some intuition and numerical evidence that the (reduced) denominator of $\displaystyle \frac{a_1}{b_1} + \frac{a_2}{b_2} = \frac{a_1b_2 + a_2b_1}{b_1b_2}$ is bounded below by $\displaystyle\frac{\operatorname{lcm}(b_1,b_2)}{\gcd(b_1,b_2)}$. I reckon that there's a simple way to prove this, but I don't see it immediately.  The bound on the other side is clear to me: the (reduced) denominator of $\displaystyle \frac{a_1}{b_1} + \frac{a_2}{b_2} = \frac{a_1b_2 + a_2b_1}{b_1b_2}$ is bounded above by $\operatorname{lcm}(b_1,b_2)$, because  $b_1b_2 = \operatorname{lcm}(b_1,b_2)\gcd(b_1,b_2)$, and $\gcd(b_1,b_2)$ divides $a_1b_2 + a_2b_1$ since it divides both $b_1$ and $b_2$,  so $$   \frac{a_1b_2 + a_2b_1}{b_1b_2} =   \frac{a_1b_2 + a_2b_1}{\operatorname{lcm}(b_1,b_2)\gcd(b_1,b_2)} =   \frac{a_1b'_2 + a_2b'_1}{\operatorname{lcm}(b_1,b_2)}, $$ where $b'_1 = \frac{b_1}{\gcd(b_1,b_2)}$ and $b'_2 = \frac{b_2}{\gcd(b_1,b_2)}$.


So I bought a new Christmas tree this year.  One with LEDs which makes setting up and tearing down simple.  It has a remote control which can set the lights blinking in different patterns.  A lot of really brilliant reds, blues, greens, violet, orange, and white.  They can dance and repeat patterns, chase each other up and down the tree, all that.  It's really pretty great.  Then I noticed something puzzling.  The replacement pack of lights.  For the tree they gave me a small packet of 6 replacement LEDs.  Enclosed is a picture of one.  My question.  How in the world would this work?  It's a two wire connection.  From the variety of colors there has to be at least 4 LEDs in there - RGB and W.  How can the CPU in the base of the tree address any light in the thread and assign it a color with only two wires?  Anyone know the protocol this thing is using?  How can they get such color diversity and positional addressability from only 2 wires?


Could you advise - which is correct?  It's my and Louise's cat. It's mine and Louise's cat. It's Louise's and my cat.  Thanks


Why does case 2 get evaluated twice in this for loop?  for (int x = 0; x <4; x++) {     switch (x)     {         case 2: printf("%d", x);         case 0: printf("%d", x);         default: break;         case 3: printf("%d", x);     } }   edit: I forgot to add that this is not a legitimate piece of code. Just something that came up in my friends job exam last week.


What will be the sign convention for radius of curvature of a concavo-convex lens ? I know for equibiconcave and equibiconvex separately but for mixed one I am not clear  .  For example for the following what will be the sign convention for radius of curvature here:


Bound for the correlation of three random variables

There are three random variables, $x,y,z$. The three correlations between the three variables are the same. That is,  $$\rho=\textrm{cor}(x,y)=\textrm{cor}(x,z)=\textrm{cor}(y,z)$$  What is the tightest bound you can give for $\rho$?


Villager trader and custom written book?

Im trying to get my villager to trade a written book i keep getting this err Expected '}' at position 223: author:me}<--[HERE}  this is the script  /summon villager ~ ~1 ~ {VillagerData:{profession:farmer,level:2,type:plains},CustomName:"\"wii\"",Offers:{Recipes:[{buy:{id:wheat_seeds,Count:1},sell:{id:written_book,Count:1,pages:['{"text":"test"}'],title:nono,author:me}:{display:{Name:"\"sand\""}}},maxUses:9999999}


I would like to store my FreeMarker templates in a database table that looks something like:  template_name | template_content --------------------------------- hello         |Hello ${user} goodbye       |So long ${user}   When a request is received for a template with a particular name, this should cause a query to be executed, which loads the relevant template content. This template content, together with the data model (the value of the 'user' variable in the examples above), should then be passed to FreeMarker.  However, the  seems to assume that each template name corresponds to a file of the same name within a particular directory of the filesystem. Is there any way I can easily have my templates loaded from the DB instead of the filesystem?  EDIT: I should have mentioned that I would like to be able to add templates to the database while the application is running, so I can't simply load all templates at startup into a new StringTemplateLoader (as suggested below).


Traveling to Germany with a French study visa

Say that someone has a French visa for study purposes. If he wants to travel to Germany by train for instance, can he go there freely without a passport or visa check?


How can i write code to check if file (csv) with name exists already?

Good day. I have code that converts results data frame to CSV. I have another code that in samae script that allows  to name the csv file.When program runs user is asked to name the csv file and its generated.Question is how can i have a mechanism in the case that user enters the same name of an existing file stored in pycharm file that prompts the user that file name exists already and enter another one.  I have tried to use if statements that check if strings is equal to existing file without success.  filename=str(input('Insert file name')) results=pandas.dataframe() results.to_csv("%s.csv"%filename)   I expect the code to check when use inputs name to check in directory if file name already exists


Overtaking regulations when driving in Europe

I've got a question about how to drive the car in Europe on Highways. In the US, I can overtake another car on either side, and I am fine.  In Europe I was told that I have to drive on the right side (Germany), and to overtake on the left side of the other driver.  Now I had following situation, and I did not know how to handle this properly: I was driving along on the right lane, the Autobahn was 3 lanes wide on my side, and was going around 110 km/h. Someone overtook me, but he stayed on the middle lane, and suddenly got slower. He wasn't really in front of me, so I could not change to the left lane, but I was told I may not overtake on the right side.  Would I have to brake in such a situation, or should I just ignore it, and overtake him again on the right side?  (I overtook him, and he was on the phone, so I guess that was why he got distracted and slowed down that much).


Is "quantizing" a field different from "quantizing" a particle?

As I understand it, quantum mechanics for particles was developed to replace classical mechanics for particles. In essence, we realized that particle cannot be given an exact place and momentum but must be described using probabilities and more specifically wave functions.   Is quantizing a field the same idea? That is, suppose I am considering an electric field $\mathbf E(\mathbf x,t)$. Does quantizing a field mean that we no longer believe the field can have a definite value at points in spacetime? Does this mean we are looking to find a wave function analogue for fields?


I'm creating a presentation with beamer, and I'm using the theme Boadilla. My problem is, the total frame number is always 1, whatever the real total frame number, and I don't understand why.  EDIT : I just had to compile two times