Update the "new contributor" indicator on meta to say "new contributor to meta"

Earlier today I saw the New Contributor indicator attached to a user who had 2,700 reputation and had been a member of the site for over 2 years. When I went to leave a comment, I saw a banner of “(User) is a new contributor. Be nice, and check out our Code of Conduct.” above the comment.  This was very confusing until I realised what was going on: this occurred on our per-site meta, and this was the first day the user had contributed to our site's meta.  Could the indicator & banner be updated on meta sites to make it clear it's not just being buggy?   Update the “New Contributor” indicator to say “New Contributor to Meta” or “New Meta Contributor” Update the comment/answer banner to say “(User) is a new contributor to this meta. Be nice, and check our Code of Conduct.”   (Text bolded just for the sake of this feature request; don't have it bolded in the released version.)


MaaS minimum requirements with juju-jitsu?

I've browsed through so many different sites and found so much contradictory information. As I am getting tired of this and do belive this question affects many other users, so I would like to collect the "once and for all times" answer. Unfortunately, the documentation on MaaS and Juju is ... well, not the best, sorry to say that.  What are the minimum system requirements for setting up a MaaS cluster, which is going to be orchestrated with juju-jitsu?  Do they need to have the exact system specifications or can I just combine different hardware?  What are the minimum requirements for the master machine?  E.g. "You need at least 8GB of RAM, a dual core CPU with at least 3.0 GHz."  How many machines to I need to deploy MaaS on?  I've read six machines, nine machines, and so on. I clearly want to know: "You need one for the Master and e.g. five nodes."  Do I need to attach as many NICs (network interface cards) to my master machine as there are nodes, or can I simply attach two NICs and a switch?   One NIC for connecting to the internet, one for handling the MaaS tasks, connected to a switch, which connects my nodes to the master?  Is Juju now ready for local deployment?  The last time I experimented with juju and had to reboot my machine, the services orchestrated by juju were gone. This was an issue I also found on the official juju site. Unfortunately, as mentioned above, the documentation is not the best, so I could not find the necessary info on that again. So:  Can I use juju on a local environment or will a reboot break my setup?


[![enter image description here][1]][1][![enter image description here][2]][2]Ok, so im currently in a crap house. Can anyone explain why all of a sudden my scene no longer renders properly. It was doing just fine up until last night.. When i rendered a scene it sometimes gives me a black image and other times no image at all. Even when i go back to scenes that rendered successfully before. I get nothing now. Any ideas??


Should one be concerned about multi-collinearity when using non-linear models?

Say we have a binary classification problem with mostly categorical features. We use some non-linear model (e.g. XGBoost or Random Forests) to learn it.    Should one still be concerned about multi-collinearity? Why? If the answer to the above is true, how should one fight it considering that one is using these types of non-linear models?


Would changing IP addresses affect my SEO

We're about to change our website from a shared hosting account to run on a VPS, mainly so we have our own resources and control over server settings.   An IP address is included with the VPS. What I was wonder is if the IP address change will have a similar affect to changing the domain name?   Obviously the links will still come from the same domain, so that's fine, but I was thinking more along the lines of the way a search engine sees the site - would it downgrade you for switching IP's?


What happens if a body jumps in the Moon?

I need to know why on Earth (ha ha..!) this behaviour happens when a body jumps in the Moon (a celestial body without any atmosphere at all).  Video explanation:   The steps I followed using Kerbal Space Program:   Start in position A Perform a clean jump on the Anti-radial vector Wait some time Slow myself to not impact the ground and kill myself. End up in position B   I know this is basic, but, should not the object end up in position A again?


Extract given column from comma-separated values with inner commas and quotation marks

I have a file in which the fields are separated by comma.  Some example input:  col1,"1,2",col3 col1,"1,2,3",col3 col1,"1  2,3",col3 col1,"1 "2,3"",col3   Now, I have to fetch the second column, so that I get:  "1,2" "1,2,3" "1  2,3" "1 "2,3""   cut -d, -f2 file doesn't do what I want.  So, how can I retrieve column 2 from the above input?


How to cryptographically verify the authenticity and integrity of Microsoft Windows .iso releases (with gpg?)

For a given Windows release published by Microsoft, how can I cryptographically verify the authenticity and integrity of the .iso file that I downloaded before I copy it onto a USB drive and attempt to install it on my laptop? Today I wanted to download Microsoft Windows 10, but the download page said nothing about how to cryptographically verify the integrity and authenticity of their release after download. https://www.microsoft.com/en-us/software-download/windows10ISO   Note: I don't have Windows, and the page above will dynamically vary depending on if it detects you're running Windows or not. In my case, it instructs me to download the .iso from the following link because I'm running Linux     I expected to see a message on the download page telling me:  The fingerprint of their PGP release signing key, A link to further documentation, and Links to [a] a manifest file (eg SHA256SUMS) and [b] a detached signature of that manifest file (eg SHA256SUMS.asc, SHA256SUMS.sig, SHA256SUMS.gpg, etc)  Unfortunately, the only information I found on the download page was how to verify the integrity of the image using a SHA256SUM found in a table on the same page. Obviously, this checks integrity but not authenticity. And it provides no security because it's not out-of-band from the .iso itself. How can I preform cryptographic integrity and authenticity verification with Microsoft Windows .iso releases?


How can I show a list of my removed posts?

I have a question ban on Stack Overflow. I read that I must improve my posts if I want to be unlocked, but I deleted 2 of my questions. How can I see the full list of my removed posts and undelete my questions? I would like to improve them.


Why does the material conditional have the truth table it does?

Can someone provide me with the simplest possible argument for why the material conditional has the truth table it does?   Googling doesn't help at all, providing only flimsy and clumsy arguments. I want the argument to be simple, and yet as convincing as possible.


In spirit of the famous  joke and  I started to think, if it's possible to design a neural network that implements $y = x^2$ function?  Given some representation of a number (e.g. as a vector in binary form, so that number 5 is represented as [1,0,1,0,0,0,0,...]), the neural network should learn to return its square - 25 in this case.  If I could implement $y=x^2$, I could probably implement $y=x^3$ and generally any polynomial of x, and then with Taylor series I could approximate $y=\sin(x)$, which would solve the Fizz Buzz problem - a neural network that can find remainder of the division.  Clearly, just the linear part of NNs won't be able to perform this task, so if we could do the multiplication, it would be happening thanks to activation function.  Can you suggest any ideas or reading on subject?


beamer: allowframebreaks option and vertical spacing when using lists (itemize, enumerate, ...)

When you use the allowframebreaks option in beamer then you get additional frames if the content is too high for one frame. The vertical spacing gets disturbed when you use a list (itemize, enumerate, description), for example, see the following animation. I used the t option (for top alignment) for the frame.     \documentclass[aspectratio=169]{beamer}   \begin{document}  \begin{frame}[t,allowframebreaks] \frametitle{Frame Title} \setlength{\mylength}{\baselineskip} \begin{itemize} \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \end{itemize}  \end{frame}  \begin{frame}[t,allowframebreaks] \frametitle{Frame Title}  Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\ Text\\  \end{frame}  \end{document}    I thought of a solution, when I read  question where they explain the different length in lists. The main idea is to check if the current frame is not the first frame of a frame continuation and add the needed vertical space. I thought that \topsep is the needed length but apparently, it is not quite right. It ist almost perfect but it still "dances" a little bit. Which additional length do I need? Here's the animation and the used code.     \documentclass[aspectratio=169]{beamer}  \setbeamertemplate{frametitle continuation}{%     (\insertcontinuationcount)%     \ifnum\insertcontinuationcount>1%     \vspace*{\topsep}%     \else%     %     \fi% }  \begin{document}  \begin{frame}[t,allowframebreaks] \frametitle{Frame Title}  \begin{itemize} \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \item Test \end{itemize}  \end{frame}  \end{document}   Related        Definition of \itemize in beamer  In beamerbaselocalstructure.sty I found  \renewcommand{\itemize}[1][]{%   \beamer@ifempty{#1}{}{\def\beamer@defaultospec{#1}}%   \ifnum \@itemdepth >2\relax\@toodeep\else     \advance\@itemdepth\@ne     \beamer@computepref\@itemdepth% sets \beameritemnestingprefix     \usebeamerfont{itemize/enumerate \beameritemnestingprefix body}%     \usebeamercolor[fg]{itemize/enumerate \beameritemnestingprefix body}%     \usebeamertemplate{itemize/enumerate \beameritemnestingprefix body begin}%     \list       {\usebeamertemplate{itemize \beameritemnestingprefix item}}       {\def\makelabel##1{%           {%             \hss\llap{{%                 \usebeamerfont*{itemize \beameritemnestingprefix item}%                 \usebeamercolor[fg]{itemize \beameritemnestingprefix item}##1}}%           }%         }%       }   \fi%   \beamer@cramped%   \raggedright%   \beamer@firstlineitemizeunskip% }   But I do not understand where the different kinds of spaces are defined that cause the "dancing".  "Evil" Stuff in beamer  Motivated by the comment of @cfr I searched the beamer documentation for "evil" stuff -- this is what I have found (beamer guide version 3.41):   Do not use subsubsections, they are evil. Never ever use the evil option shrink.  Using this [again shrink] option is very evil. The use of this [allowframebreaks] option is evil.


How can I package a custom keyboard layout for personal use?

I've created a custom keyboard layout, but I want to use it on multiple computers. How can I package up my custom layout in such a way that I can easily install it on other computers?  I've begun following the steps outlined , but there are two problems with the accepted answer.   The answer appears to be obsolete, since Bugzilla now gives me the error . The answer is not detailed enough for me. I've made what I think are the correct modifications to the git repository, but now what? The answer just says to use "standard dpkg build tools", but I don't really know what that means.


A scientist who has led a drab but blameless life decides to sell his soul to a demon, or maybe the Devil himself, in exchange for a task. If memory serves, the demon heads the terrestrial branch of Hell, but is only one of many in the Universe. He is not in charge of Hell, but hopes to win the next election, for he is not only clever, but justifiably proud of his work on Earth. He looks forward to providing this puny man with whatever he wants, which will take only a finite amount of time; he can return through time and resume his own ambitions. It doesn't matter whether the man wants wealth, pleasure, or fame; the task will not take long from his point of view, and another soul will be lost to heaven forever. So the demon agrees readily before hearing what the task is. It's always worked before. Heaven trembles.  And then the scientist states his terms. The demon's task is to provide the scientist with safe transportation and measuring instruments in space and time, because he has never felt much attachment to other people but is curious about everything. He will deduce the physical laws, structure, and history of the entire Universe. Oh, and he wants no hints or interruptions, so please be silent; he will deduce all this by himself. The demon exclaims, more or less, "But that will take longer than the entire duration of the cosmos!" He realizes that having been stung like this, he will never be elected to a higher position even if he still wants to after returning from so long a period as the scientist's assistant. Heaven smiles. The scientist directs the demon to the Earth's core, where, he says, he would like to resolve some longstanding questions in physics.  The story was read in an English-language anthology, probably in the 1960s or 70s.


Find $\lim_{x \to 0} \frac{x - \tan(x)}{x - \sin(x)}$

I am trying to use L'Hopital's rule, but I'm not sure if I'm doing this correctly. In my textbook, the rule is stated as follows:  $(f(a) = g(a) = 0) \Rightarrow$ $\lim_{x \to a} \frac{f(a)}{g(a)} = \frac{f'(a)}{g'(a)}$ (given $\frac{f'(a)}{g'(a)}$ is defined)   So in this case, I have $f(x) = x - \tan(x)$ and $g(x) = x- \sin(x)$, both of which are $0$ at $x = 0$. Also, $f'(x) = 1 - \sec^2(x)$ and $g'(x) = 1 - \cos(x)$. However, wouldn't this mean the RHS isn't defined, since $\frac{f'(a)}{g'(a)} = \frac{0}{0}$? I am confused how to resolve this.


Email validation regular expression in cshtml using jquery pops error

While validating email textbox using regex and jquery in shtml page, error pops showing issue with regex as it contains "@" in the regex.  $(document).ready(function() {  $('#btn-submit').click(function() {       $(".error").hide();     var hasError = false;     var emailReg = /^([\w-\.]+@([\w-]+\.)+[\w-]{2,4})?$/;   //"@" in regex is the issue      var emailaddressVal = $("#UserEmail").val();     if(emailaddressVal == '') {         $("#UserEmail").after('Enter email address.');         hasError = true;     }      else if(!emailReg.test(emailaddressVal)) {         $("#UserEmail").after('Enter a valid email address.');         hasError = true;     }      if(hasError == true) { return false; }     }); });


What is the general formula for a sequence that is neither arithmetic nor geometric?

If a sequence is such that the next term is given by $a_n*a +b$, what is the general formula of the given sequence?  e.g.: $-$ for $a=4,\;b=6$, the sequence is:  $1,\quad1*4+6=10,\quad10*4+6=46,\quad46*4 +6=190,\;\dots$  What would the formula for the general term be?  (I'm not necessarily asking specifically for this example but rather for a general sequence with the next term defined by $a_n*a +b$).


Cite all @article-s in the bibliography (BiBLaTeX)

Is there any way to cite all articles in the bibliography (i.e. BiBTeX entries with @article type)?  I know there is a type option in the \printbibliography command. I want something like \cite[type=article]{*}...  UPD: For example, I have 100 articles in the bib file and 100 proceedings. I want to print the bibliography that shows the articles first, then the proceedings.  If I use the following code  \nocite{*} \printbibliography[type=article,title={Articles}] \printbibliography[type=inproceedings,title={Proceedings}]   I will have bad numeration (since the articles and the proceeding are "mixed" in the bib-file:  Articles: 1. Article#1 3. Article#2 4. Article#3 ... 183. Arctice#100  Proceedings: 2. Proceeding#1 5. Proceeding#5 ... 200. Proceeding#100   P.S. Manually citing all the papers in the correct order (\cite{article1, article2, ..., article100, proceeding1, proceeding2, ..., proceeding100}) is not a good option.


What does "made to last" means in this sentence: made to last since nineteen eighty two?


Exporting 60 PDF files from each MXD in ArcPy?

I need to export 60 PDFs files so I am thinking if there is a way around to export 60 without having to open each MXD file at a time ?  I am using ArcGIS 10.1 SP1  Build 3143 .


Is there a way to auto-resize programs like in Windows 7 and up?

One of my favorite Windows features is the ability to slam a program into the side of the screen to auto-resize it to fill that half of the screen.  Is there any program I can download for Mac that makes this feature available on macOS?


Should there be a comma before "but instead" in the following example?

Am I correct to include a comma before "but instead" in the following example? I am not sure if the latter part of the sentence could be considered a main clause because there is no subject, so I am not sure if I am right or not.     The manual holds that women must not choose a programme themselves, but instead wait to be assigned to a module.


Ordering negatives with should (or shouldn't) + verb

There was some debate at work the other day as to the correct form in the following case:  1) I don't think you should do that.  or  2) I think you shouldn't do that.  A few of us set off on a Google spiral that threw up a few hits but with nothing - as far as I can tell - with a definitive answer. There were a few threads here, but none that were dealing specifically with this issue.  A few also came up at wordreference, but there was nothing definitive, and some contradictory answers seemed to surface. From the research we found the following:  1) Americans say either, but the British always prefer to put the negative first (as in: I don't think you should). 2) There is a slight variance in meaning (at least denotational if not literally grammatical) when one places the negative first.  There were many other things said, but no research was provided.  So I am asking here if anyone has a definitive answer, or is this simply a stylistic choice possibly conditioned by whatever side of the Atlantic you happened to grow up?  Apologies for the rambling post.  Much appreciated.


No more WIFI. oem-wifi-intel-iwlwifi doesn't build on the new 4.4 kernel

i have trouble with internal wifi card on my Dell Latitude 5590 runing Ubuntu 16.04 LTS.  What happend before problem occured:   I recieved notification that my laptop has updates, updated it, enrolled MOK (as it begged) and everything worked fine. I decided to remove Code::Blocks, which resulted into  Restarted pc and Ubuntu lost embedded wifi adapter   sudo lshw -C Network shows    *-network UNCLAIMED             description: Network controller        product: Wireless 8265 / 8275        vendor: Intel Corporation   lspci -nn recognizes adapter  02:00.0 Network controller [0280]:   Corporation Wireless 8265 / 8275 [8086:24fd] (rev 78)   and rfkill list output is  0: dell-wifi: Wireless LAN     Soft blocked: no     Hard blocked: no 1: dell-bluetooth: Bluetooth     Soft blocked: yes     Hard blocked: no 2: phy0: Wireless LAN     Soft blocked: no     Hard blocked: no   As far as i understood the problem is in oem-wifi-intel-iwlwifi-lp1757035-4.4-dkms-dkms, because then i try to reinstall it with sudo apt-get install --reinstall oem-wifi-intel*, it stops, signaling Bad return status for module build on kernel: 4.4.0-143-generic


Show that $|f(0)| \leq \frac{1}{4}$ for every holomorphic function $f:\Bbb D \to \Bbb D$ such that $|f(\frac{1}{2})|+|f(-\frac{1}{2})|=0$

Let $\Bbb D= \{z : |z|<1\}$ be the unit disc. Let $f:\Bbb D \to \Bbb D$ be a holomorphic function such that $|f(\frac{1}{2})|+|f(-\frac{1}{2})|=0$. Prove: $|f(0)| \leq \frac{1}{4}$.  The only thing I thought about was using Schwarz lemma, but I'm not sure how. I thought about defining $g(z)=\frac{f(z+\frac{1}{2})+f(z-\frac{1}{2})}{2}$, but now $g$ is not defined in all $\Bbb D$, and I'm pretty much stuck.


2 SFMC Business Units Connected to 1 Sales Cloud Org

We are exploring the possibility of having 2 separate business units in one Enterprise 2.0 SFMC account connected to 1 Sales Cloud org via the MCC connector. Is that possible? We don't have issues with having a separate API user for both connections, and the MCC is already up and running, establishing 1-to-1 connections between various SFMC BUs and Sales Cloud orgs.


I have installed Kubuntu on my Ubuntu 16.04 install.  After running apt-get remove ... and apt-get purge I STILL have kubuntu installed. Apps that were installed with Kubuntu like Konsole is still installed, Kubuntu loading screen shows on boot up, and I can still select Plasma as my desktop on logon.  How do I just revert back to plain Ubuntu completely????


Graphic sequence with least common multiple

Does anyone know how to prove this:  Let $S=(a_1, a_2,...,a_n)$ be a finite set of different integers.  Let $k$ be the least common multiple of $(a_1+1, a_2+1,...,a_n+1)$.   Show that the sequence resulting from taking all the numbers in $S$, $k$ times each is a graphic sequence.


How can I deselect selected parts in object mode?

I have been trying to animate recently and my project is due tomorrow so pls help me on which key to press if I want to deselect in object mode


Why does "redirect to a file" is executed as user, even with sudo?

I often encouter this problem and it really bugs me on why it is so. So let's take this example into account :  [me@localhost:~]$ sudo command > /some/file.log   As far as I know, this will not work if the user has no permission to write in /some/file.log, even if the command is executed as sudo. I found some workarounds on this website so that's not a problem, but I would like to know what is the reason behind it ? Why would the command be executed as sudo, and the redirection as user ? Any solid reason to back this up ?


How to achieve same battery life on Ubuntu LTS 16.04 as Windows 10 using Nvidia graphics adapter?   I've tried disabling the Nvidia 940MX in BIOS, but there is no option available to do this.  I know that Ubuntu comes with Nvidia drivers installed (Nouveau), however the performance and battery life are much worse compared to Windows 10 with original Nvidia drivers.  Is it possible to disable the Nvidia graphics adapter completely when running Ubuntu, such that only the Intel graphics card consumes power?  In this case, I will achieve Windows-like battery life, right?


Putting a point over pixels with highest DN values within grids in QGIS

I have a raster layer in greyscale, and a vector layer that is 3 x 3 m grid. One of the attributes within the grid cell layer is the value of the highest DN number within that grid cell. I just need to get a point over the highest pixel for each grid cell. That's it. I've tried a number of methods involving converting pixels to points so you can table join, but there's too many grid cells and QGIS crashes!


Plurals of acronyms, letters, numbers — use an apostrophe or not?

When I was in high school back in the 1970s, I was taught that to make a plural of an acronym, a letter, or a number, one should add an apostrophe and "s". Like I would have written this sentence, "... back in the 1970's ..." I would write "one CD, two CD's". Etc. I followed this rule faithfully for years until a co-worker told me it was wrong. Now I can't find any source that agrees with what I was taught.  Is this a rule that has changed over time? Was the convention in the 70s that one should use an apostrophe but this has changed and now we do not? Or were my high school English teachers just confused?


is there really some difference between if and whether?

I've had a doubt about when I use if and whether. I saw an phrase using whether and now I'm thinking when really use it.  The phrase:   I don't know "whether" it was the burden of having to raise a large family, or his natural confidence in dealing with people, but my dad became an immediate success in his newfound profession.  Can I replace whether for if? However,  when I use whether?


Hot network questions should not include locked questions

I was just now led to , which appeared under "Hot Network Questions". However, it is locked since yesterday. Certainly, questions which are closed or locked should not be advertised as hot questions, so I believe this is a bug.


When symbolising by category can I make the transparency different for each category?

Normally when I'm making something semi-transparent I edit the transparency in layer properties, but now im trying to make something in the layer (a symbol level) semi transparent. I want to edit the transparency of each fill symbol when I've symbolized by category. is this possible in ArcGIS 10.0?


Use whole page width in twocolumn document

I am working with my document class set as [twocolumn]{article} and all is working well however I would like to know if it is possible to use the whole page witdth for text within the document.  I have tried using \centerline and center to try and nudge the text however they only centre to the middle of the column (as expected).  I also cannot use multcols so I am stuck to whatever is possible with twocolumn.    Edit:  \documentclass[twocolumn]{article}  \usepackage[italian]{babel} \usepackage{cuted} \usepackage[T1]{fontenc} \usepackage{varwidth}  \AfterEndEnvironment{strip}{\leavevmode}  % Allow me to use \newpage to swap sides. \makeatletter \renewcommand*\cleardoublepage{\clearpage\if@twoside   \ifodd\c@page \hbox{}\newpage\if@twocolumn\hbox{}%   \newpage\fi\fi\fi} \makeatother  \begin{document}  \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Fare}} \begin{description} \item io faccio \item tu fai \item lui/lei fa \item noi facciamo \item voi fate \item loro fanno \end{description} \end{minipage}% \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Andare}} \begin{description} \item io vado \item tu vai \item lui/lei va \item noi andiamo \item voi andate \item loro vanno \end{description} \end{minipage}% \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Potere}} \begin{description} \item io posso \item tu puoi \item lui/lei può \item noi possiamo \item voi potete \item loro possono \end{description} \end{minipage}  \vspace{0.5cm} \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Leggere}} \begin{description} \item io leggo \item tu leggi \item lui/lei legge \item noi leggiamo \item voi leggete \item loro leggono \end{description} \end{minipage}% \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Scrivere}} \begin{description} \item io scrivo \item tu scrivi \item lui/lei scrive \item noi scriviamo \item voi scrivete \item loro scrivono \end{description} \end{minipage}% \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Parlare}} \begin{description} \item io parlo \item tu parli \item lui/lei parla \item noi parliamo \item voi parlete \item loro parlano \end{description} \end{minipage}  \vspace{0.5cm} \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Sapere}} \begin{description} \item io so \item tu sai \item lui/lei sa \item noi sappiamo \item voi sapete \item loro sanno \end{description} \end{minipage}% \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Conoscere}} \begin{description} \item io conosco \item tu conosci \item lui/lei conosce \item noi conosciamo \item voi conoscete \item loro conoscono \end{description} \end{minipage}% \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Pensare}} \begin{description} \item io penso \item tu pensi \item lui/lei pensa \item noi pensiamo \item voi pensate \item loro pensano \end{description} \end{minipage}  \newpage  \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Capire}} \begin{description} \item io capisco \item tu capisci \item lui/lei capisce \item noi capiamo \item voi capite \item loro capiscono \end{description} \end{minipage}% \begin{minipage}[t]{.165\textwidth} \textsc{\textbf{Studiare}} \begin{description} \item io studio \item tu studi \item lui/lei studia \item noi studiamo \item voi studiate \item loro studiano \end{description} \end{minipage}  % Adding a strip environment here breaks the layout. % This is where I want my full-page text.  \end{document}


How to show that $(0,1)$ and $[0,1)$ are not homeomorphic?  My attempt:  On contrary suppose it is then  there exist $f:[0,1)\to (0,1)$ which is continuous   But inverse image of open set is open   So contradiction  Is my argument is correct?


Running sudo fdisk -lu returns the hdd I want to mount as  Disk /dev/sdb   but when I try to mount it from KDE Partition Manager it doesn't show some directories when I try to set up a path (tried showing hidden folders, only displayed 3) and through the konsole with sudo mount /dev/sdb /mnt, I get  mount: wrong fs type, bad option, bad superblock on /dev/sdb,    missing codepage or helper program, or other error     In some cases useful info is found in syslog - try    dmesg | tail or so.   so I tried running sudo e2fsck -f -b 32768 -y /dev/sdb and get  e2fsck 1.42.13 (17-May-2015) e2fsck: Bad magic number in super-block while trying to open /dev/sdb  The superblock could not be read or does not describe a valid ext2/ext3/ext4 filesystem.  If the device is valid and it really contains an ext2/ext3/ext4 filesystem (and not swap or ufs or something else), then the superblock is corrupt, and you might try running e2fsck with an alternate superblock:     e2fsck -b 8193 <device>  or     e2fsck -b 32768 <device>   and when I try those variations I get the same message. How do I mount this hard drive? The file type for the hdd is "inode/blockdevice" and I've already created a partition for it but it won't save without a path.  Also, why does it say 17-May-2015?  Many thanks.    EDIT: Was able to find the /dev folder by clicking the bar next to "Look in" however the partitions don't show up even as hidden files but it does show up if I type it into the "Directory:" bar but its not selectable ("Choose" is greyed).    Gparted, as expected, no difference. I'm sure its a file type error..    Re-partition the hard drive in gparted:    and after applying the settings it seems to have worked but upon opening my file manager, the "Devices" listing on the leftside has disappeared! My ssd is not even listed (as it had been before) "Devices" title is not there!


Is it a foul to pause during a run-for-shot in penalty shootout?

During the penalty shootout of , in Croatia's 2nd shot (Andrej Kramarić vs Kasper Schmeichel), when Kramarić was running for a shot, he paused briefly before continued to run for the shot, then shot and scored a goal. Schmeichel fell for the trick, thus missed the ball. Right after the goal, Schmeichel showed expression claiming Kramarić's procedure was a foul/invalid conduct. However the referee acknowledged his goal and let the match continue.  My question is: In FIFA's rules, during a penalty shootout, is it a foul or misconduct if a shooter pauses briefly while running or before a shot to trick the goalkeeper?  (A note: I do recall reading the rule somewhere, stating that the mentioned "trick" is indeed a foul for unsportmanlike conduct, but I cannot find the source or citation anymore. I might have remembered it wrong, though.)


What happens to the holes in the skull where teeth were developing?

In Skeptics.SE, a question regarding the skulls of children arose. Depicting a scary skull where the permenent teeth are "hidden" inside the jaws and the milk teeth are in the their place.  After all milk teeth fall out, and the permanent teeth "rise", do the holes left by them filled up, or do we go around with holes in our jaws?    The picture:


Probability that $n$ points lie within a semicircle - different approach

The main question is that what is the probability that $n$ points on a circle lie on the same semi circle. I was trying to solve the question by thinking about the following equivalent question:  What is the probability of selecting $n$ $\textit{Uniform(0,1)}$ numbers such that their range is less than $0.5$. I have attached an image with the derivation of the range of $N$ uniform random variables.  If you plugin $d=0.5$ in the cdf for the range of uniform distribution, we should get the answer but the answers don't match. What is wrong here? The answer should be $\frac{n}{2^{n-1}}$ but using the cdf the answer is $\frac{n+1}{2^n}$.


Are J.K. Rowling interviews Harry Potter canon? What happens to canon if there's a discrepancy with the book?

It seems that a lot of Harry Potter questions (including my last one) are answered based on tidbits of info that J.K. Rowling provided in various interviews.  I have two related questions (I'll post them separately):  Question #2 of 2. If there ever is a discrepancy between what JKR states in an interview, and a book, which one is considered canon? Book? JKR? Whatever is later?   (What made me think about this was the whole thing with George Lucas and his multiple layers of canon and the whole "L'État c'est moi" Luis-the-14th schtick he has).


what is diference between using java and best use case  I am not able to understand the difference b/w these two concepts can any body explain with example.   Map<string> map =new Hashmap<string>();  Hashmap<string> map =new Hashmap<string>();     and which is better usage.  Note:can any one guide me best ebook for java collection and Data structure


what is the difference between sockets and ports in a computer network?

I have trouble understanding this, for example:-  I have tried connecting to google server(via http process) and also tried connecting to Youtube(again http process), will different sockets be created for each connection?  if i have different sockets, will port numbers be different since a socket is a combination of IP and port and IP here is fixed(my computer)?


Evaluation of $\int_{\frac{1}{e}}^{\tan x}\frac{t}{1+t^2}dt+\int_{\frac{1}{e}}^{\cot x}\frac{1}{t(1+t^2)}dt$

$$\int_{\frac{1}{e}}^{\tan x}\frac{t}{1+t^2}dt+\int_{\frac{1}{e}}^{\cot x}\frac{1}{t(1+t^2)}dt$$   $\bf{My\; Try::}$ Let $$f(x) = \int_{\frac{1}{e}}^{\tan x}\frac{t}{1+t^2}dt+\int_{\frac{1}{e}}^{\cot x}\frac{1}{t(1+t^2)}dt$$  Put $\displaystyle x = \frac{1}{u},$ Then $\displaystyle dx = -\frac{1}{u^2}du$ and changing limits, We get  $$f(x) = \int_{\frac{1}{e}}^{\tan x}\frac{t}{1+t^2}dt+\int_{\tan x}^{e}\frac{1}{u(1+u^2)}du$$  So $$f(x) = \int_{\frac{1}{e}}^{\tan x}\frac{t}{1+t^2}dt+\int_{\tan x}^{e}\frac{t}{1+t^2}dt = \frac{1}{2}\int_{\frac{1}{e}}^{e}\frac{2t}{1+t^2}dt$$  So $$f(x) = \frac{1}{2}\ln (1+t^2)|_{\frac{1}{e}}^{e} = \ln(e) = 1$$  My question is how can we solve it in some shorter way, Help required, Thanks


Does increasing the tension on a string also increase the density

Does increasing the tension on a string also increase the wave speed


Showing labels just for a specific point type

If I have a bunch of points all on the same layer and they are all categorised by different types in the Attribute Table, is there an easy way to just show labels for one type and not the others? Maybe through an expression?


Whats the best way to expose current settings to your classes?

Just as the title states, whats the best way to expose current settings like resolution to my classes? (I know this might have been asked, but I couldn't find anything)  I was thinking of the service-locator design pattern, but I am unsure, as I read that it can be abused easily.( I mean it might not fit this particular use-case )


I have made many loaves of bread, but I just got my starter done for my first Sour Dough loaf.  I’m following a recipe to the letter, and am now in the kneading phase, my question is that the dough is still quite sticky, it seems like it is working well between kneading, but is a bit difficult to handle. Can I give it a light dusting of flour before kneading to make handling a bit easier?


Why are Integration and Differentiation inversely related?

This question may seem to be off-topic, So before flagging or reporting as off topic, feel free to comment and I will delete this question.  I have recently studied high school calculus and I am still wondering that how are integrals and derivatives related to each other?  Is this just a coincidence?  Or there is a logic that I am still not aware of.  Out of my curiosity I asked this question to my teacher but I didn't get any satisfactory answer.   And one more question,  How definite integrals calculate area of the given function.I asked this too, then my teacher replied that when we integrate $y(x).dx$ ; $dx$ is a small strip of width $dx$, parallel to $y$-axis and $y$ is it's height, so together multiplied it gives area in that rectangular region and the integral sums it up.  But then I found a question on this website asking : Is $\frac {dy}{dx}$ not a fraction? and it turned out that it isn't.Therefore we can't consider $dx$ as width, after all, it's a operator.  So what is going on?


How do I prove that if $A$ is a $n\times n$ matrix with integer entries, then $A^{−1}$ has integer entries if and only if $\det(A) = ±1.$

I have no idea how to solve this. One of the hints is that I "can use the classical adjoint of $A$"


I have trouble understanding why some words change "s"-es to "z"-s from BE to AE and some not. For example:   analyse -> analyze characterise -> characterize hypnotise -> hypnotize   But:   compromise -> compromise   Is there any rule to this?  Slightly related:


Accidentally used replaced Source-list with wrong Ubuntu version

I ran these commands:  sudo wget "http://pastebin.com/raw/uzhrtg5M" -O/extras/Source-list sudo apt-get update   But it seems that I have replaced my Source-list with a Source-list of wrong version, since I am using Ubuntu 14.04 LTS but the source from which I downloaded was for Ubuntu 12.02 LTS.


Ubuntu 17.04 why chrome-remote loops back ubuntu default dekstop environment?

I have installed Ubuntu 17.04. For a while it worked great. Then I have installed a couple of packages which I don't remember. When I rebooted my laptop, I couldn't login from the default login desktop environment. Every time I try to login, it accepts the password, but loopsback to login screen again. But from the Unity8 desktop environment I can login without a problem. its not a startx, lightdm,owner problem etc..


Why does the magnitude of the cross-product of a and b give the area of a parallelogram spanned by a and b?

I tried looking it up but many websites just state it without proof and without intuition.  I'm hoping to learn it a little bit better so that I don't forget how to compute the Jacobian when working with surface integrals where the divergence theorem is not applicable.  If you have a good online reference instead, please feel free to provide it :-)  Thanks,


When do I use active vs passive perception?

So, I'm trying to figure out how to run the scene from the beginning of Lost Mine of Phandelver (5e starter set) where the party is ambushed by goblins and I'm really confused as to how Passive Wisdom (Perception) works.  The included rulebook mentions on page 6 :     When you hide, there’s a chance someone will notice you even if they aren’t searching. To determine whether such a creature notices you, the DM compares your Dexterity (Stealth) check with that creature’s passive Wisdom (Perception) score, which equals 10 + the creature’s Wisdom modifier, as well as any other bonuses or penalties. If the creature has advantage, add 5. For disadvantage, subtract 5. For example, if a 1st-level character (with a proficiency bonus of +2) has a Wisdom of 15 (a +2 modifier) and proficiency in Perception, he or she has a passive Wisdom (Perception) of 14.   So the party is being ambushed by goblins and at that point the DM guide mentions on page 7 :     Check to see who, if anyone, is surprised. [...] Make a Dexterity (Stealth) check for the goblins, rolling once for all of them. Roll a d20, add the goblins' Stealth skill modifier (+6) to the roll and compare the result to the characters' Passive Wisdom (Perception) scores.   So to me this reads like I should roll 1d20+6 for the goblins and compare that to the static Passive Wisdom (Perception) score on the character sheet of a PC. The PCs don't get to roll anything as they're not actively looking for enemies, even though they are investigating the dead horses.  I would also think that if the characters were supposed to roll, the DM guide would clearly instruct so, given that this is the starter set.  However, watching  at around 8:01 I notice that the DM is explicitly asking his party for a perception roll. And the same thing happens on a couple of other videos where people are running the Lost Mine adventure. The DM always requests a roll.  So what gives? Shall I take it that the DMs ask for the roll because they consider the party to be actively seeking for hidden foes? Or am I just misreading the rulebook and the DM guide?


Why doesn't Stack Overflow sort by votes anymore?

Within the last week or so, I noticed Stack Overflow no longer sorts by number of votes. Aside from the answer with the most votes, which does seem to come first, the rest of the answers seem to be in a random order. What's going on here?  ex:   Notice the answers here have 195, then 3, then 29 votes. The 3 should come after the 29!  There's also a 17, 40, and 28, in that order, far after the 29 here too. what's going on!? And this isn't just this one answer, this is happening with nearly every answer I've looked at over the past week or so.  It makes finding the top few best answers quickly really difficult.


how to know what kind of tires work for my fork?

I want to know how select the tire depends on the bike or fork because actually I have the following problem.  Currently, I have a specialized diverge whit this fork. Specialized FACT carbon, flat-mount disc, 12x100mm thru-axle. I want to change my tires for a continental speedride 700x42c. how I know if this kind of tire work on my bike.


Unknown ssh connections found in lsof -i has my server been compromised?

I have a Digital Ocean droplet running Ubuntu 14.04. I use it for running quick node.js tests on a publicly available server. I just logged in via SSH and did $ lsof -i to see what ports I was using. At the bottom of the list I noticed:  sshd    30952 root    3u  IPv4 66978103      0t0  TCP xxx.xxx.xxx.xxx:ssh->120.52.72.81:7810 (ESTABLISHED) sshd    30953 sshd    3u  IPv4 66978103      0t0  TCP xxx.xxx.xxx.xxx:ssh->120.52.72.81:7810 (ESTABLISHED)   I didn't expect these ssh connections (it should only be me!) so I looked up the IP address and it seems to be in China. So what should I do now to check whether these ssh connections are malicious and if so what they may have done to the server. I'd rather not nuke it but if it's been compromised (since they have root access I presume it has!) then perhaps that's the simplest thing to do.  Update: Since writing the above, I have 2 different SSH connections so I presume it really is compromised.  sshd    31009 root    3u  IPv4 66979206      0t0  TCP xxx.xxx.xxx.xxx:ssh->221.194.44.218:50829 (ESTABLISHED) sshd    31010 sshd    3u  IPv4 66979206      0t0  TCP xxx.xxx.xxx.xxx:ssh->221.194.44.218:50829 (ESTABLISHED)   If anyone can suggest a sensible approach to checking for a compromise/cleaning this up/seeing what's happened that would be great to help me learn (I'm such a n00b!).  Update 2: It appears that this isn't signs of a compromise but rather the signs of brute force log in attempts - see the comments from  and  below.


How to disable Auto - Keyframing in Blender 2.8

Yesterday Blender 2.8 was released and it was exciting for me. But when I move the objects in the viewport, a keyframe gets added, which is quite annoying. Could someone tell me how to turn this off? Thanks in advance (:


How to reinstall GRUB bootloader for 14.04 after upgrading to Windows 10

What do I do to reinstall the GRUB boot-loader, since I heard the Windows boot-loader overwrites GRUB.


In physics, one of the ways to solve problems is to find a similar mathematical model which describes the problem, and that leads to my question: By experiments we familiar with the space of time, we know how to find the right time when a rocket reached the height of $10$ kilometers, or what is the exact time when an object will fall to the ground in free fall. To solve these problems we are using infinitesimal calculus, but the usage of "calculus tools" is allowed when the topology on the space of ($1$ or more dimensional) time is the euclidean topology. How do we know the time is not a discrete space? After all, we usually say "one moment please", if the space of time is built out of "moments", then the time is discrete, therefore compact sets are useless because now the compact sets are only finite sets, which means that the  is nothing, and the time is not even connected. Why only by experimants we can determine the topology of time? Or is it just a convention as a mathematical model?


What are the unit elements in $\Bbb{Z}[i]$?

What are the unit elements in $\Bbb{Z}[i]$, where $\Bbb{Z}[i]$ is defined to be the set of Gaussian integers ? My progress: My mentor gave this problem and he said to use determinants and scalefactor. Then I was able to proceed and got the unit elements in $\Bbb{Z}[i]=1,-1,i,-i$ , which is correct . However, I wonder if there is some other way to proceed . Any solution or hint is appreciated . Thanks in advance.


Running 5VDC circuits off a rechargable ni-cd batteries that can recharge in-circuit from a DC power supply

Here's what I'm trying to do.  I'm trying to make it where I can run any circuit requiring 5 volts off of 7.2 volts. I get 7.2 volts from combining two 3.6v ni-cd phone batteries but for simplicity I show it as one center battery in my circuit.   The source power shows as a battery but I plan to use a wall adapter that outputs either 9VDC or 12VDC, but I figure 9VDC is more efficient.  The battery shown on the right is the output (5V). I could replace it with an LED and resistor in series but I used a battery symbol for simplicity.  Here are my questions:   If I used such a circuit, would I be able to successfully charge a ni-cd battery to max charge without blowing up the battery or is my circuit flawed? If my circuit can be successful, is there a way to modify my circuit so that I can connect a wire to a GPIO pin of an AT89C2051 so that it can detect when a battery is charged/still charging without negatively affecting the charging process.   and    Could I change the variable voltage regulator (LM317) to an 8V fixed voltage regulator to charge the 7.2V battery with a resistor in series? If so, what resistor value?   I'm asking all this because I want to make a low-priced in-circuit battery charger for my microcontroller projects and I don't want to have to remove the battery in order to charge it.    Why this question isn't duplicate  I want to build the charger circuit using discrete components that are commonly available in anyone's junk box. I don't want to have to purchase a special IC and wait weeks for it just in order to charge batteries. Additionally, I'm looking for a modification to this circuit to make my charger more efficient. I adapted parts of it from talkingelectronics.com.


How CVs in discipline with numerous co-authors are examined?

In some disciplines such as theoretical physics, it is common to have tens (or even) hundreds of co-authors, probably because of the essential role of many people to run highly advanced facility.  How is the list of publications in these disciplines judged? For a faculty appointment, how does the search committee realize the scientific contribution of the applicant?


?  The above link to JAD (a Java decompiler) is not working. Is there any other place where I can find a Java decompiler?


What kind of grammar explains the common string "Let us"?

What kind of the grammar is shown by the group of two words "let us"? Is it a phrase or a predicate or a clause ... or something else?


Was Grendel supernaturally protected from weapons?

In a similar vein to , is the statement that Grendel can't be harmed by weapons a claim about some supernatural protection he's had, or a prediction about how he's going to be defeated?  Update: I mean in the ancient epic poem, not the recent film.


How to forbid the access to file from other processes in python?

I have a file, and several processes which can operate on it. For simplicity let us assume that each process runs the same script: with open("file.txt", "r+") as file:     data = file.read()     data = data + "Hello\n"     file.seek(0)     file.write(data)  I assume that such a way of file access allows several processes to modify the same file, what results in improper writing (for instance, three processes could get "HeHello\nHello\nllo" as a result). Is there any way to forbid access to the file for some time and still be able to read and write from there from the current process?


Number theory question involving Wilson's theorem. How to solve??

Given p is a prime number greater than 2, and  $ 1 + \frac{1}{2} + \frac{1}{3} + ... \frac{1}{p-1} = \frac{N}{p-1}$   how do I show, $ p | N  $ ???  The previous part of this question had me factor $ x^{p-1} -1$ mod $p$. Which I think is just plainly $(x-1) ... (x-(p-1))$


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


I installed the Intel's graphics drivers from ;  After reboot, the GUI doesn't start and hangs with the text "starting version 219" on a black background.  I'm trying to install these drivers because I use the built-in GPU with a second display and I'm experiencing a terrible screen tearing effect.  My primary graphic card is an AMD Radeon 7000 series (not FGLRX). It had screen tearing too, which I solved using Compiz. The problem is that the second monitor still has this problem (with Compiz enabled).  Do these drivers work on Xubuntu 15.04 (or Ubuntu 15.04, which has the same problem)?  Could they solve the screen tearing on the second display?  Can I use both the Intel and the FGLRX drivers like I did on Windows?


With "implements" I can force a class to define certain functions, but I need to add some functions to the interface to avoid duplicate code. This is only possible if I make the class "abstract" and use "extends". But "extends" only accepts one class. Because each of these classes are different, sort of like features of an app, I can't just extend one with the other. So is there any way to have   class My extends Feature1, Feature2, Feature3{ }   ??


Why do (most) metals cause problems in a microwave oven? Which metals (if any) don't?

Most of us have seen microwave ovens with metal racks or shelves, which challenges the common notion that you can't (safely) put metal in a microwave oven.  What's going on here?  Is it a matter of these shelves being made of a specific metal (if so what are the properties that allow it to be used in a microwave oven?) or of being placed in just the right place in relation to the waves that will be emitted, or something else entirely?  If it is a matter of using just the right metal (or alloy), then which metals are okay to use in a microwave oven?


One of my colleague asked me that "What time can I call you". I need to answer him.  Is this correct? If not please suggest the correction(s).


How we can specify figure page in LaTeX?

How we can specify figure page? For example I want show a figure on top of page 5.


Strange seams while rendering glass object

a newbie question that has probably been answered before, but I couldn't find a definitive answer:   I'm trying to render a simple glass container with some dark liquid in it, but I'm getting weird "seams" on the round edge of the container in rendered image. It's as if the normals are somehow miscalculated and causing the refractions to render incorrectly. This should not be the case, as I have recalculated the normals for the outside, as you can see from the image. I used the Solidify modifier to get the container, original mesh only had single faces for all the sides (and the rounded end) minus the top face, no other modifiers used. The liquid is a separate object that I created by copying the inside of container.  So, what's causing those seams to appear and what can I do to get rid of them?  The problem, circled with red:   A view from my editor, as you can see, normals seem to be OK:


A water pipe from sea level to beyond the atmosphere

If a pipe extended from just above the ocean floor to outside the atmosphere, would water be sucked up it by the vacuum beyond the atmosphere? If a hole was made in the pipe, above sea level, how would that affect the flow of water? Would it stop it completely?


How to get a single character without pressing enter?

How can I get a single keyboard character from the terminal with Ruby without pressing enter? I tried Curses::getch, but that didn't really work for me.


Wrong mv command. Where did my files go?

I used the command  mv folder_name ....   I thought by using .. twice, it would move it back two folders.   Unfortunately my files disappeared.   I need to recover them.


Is it safe to change my WordPress site's post permalinks?

If I change my site's post permalink structure, will it have any negative effect on my site's ranking?


Can I create a TIN from contours lines (shp) in QGIS?

I need to do a slope analysis, and would like to make a TIN from 2m contours lines.  Or do a slope analysis directly from contours? The only DEM available is not precise enough.  I do not have any elevation raster files.  And how do I then make slope classes?  The TIN properties does not seem to be able to classify anything other than elevation.


Singleton (sharedInstance) nil after recommended init

I have been looking around for solutions on how to create a singleton pattern which is thread safe on ios. I came upon basically the same solutions over and over but when I init the object the pointer still says null. As you can tell from the screenshot.  It's pretty strange since nobody on the internet seems to have had this issue so far. I myself need to compare if the sharedInstance is initialized to enter a certain piece of code somewhere else and it will always tell me after init that it is nil.  What's this about? Anybody any clues? I want to understand! :D  Thanks in advance, cheers, Thor  // Why this is not a duplicate: // This question is not about the proper init it is about why the sharedInstance is not behaving like it should after. I still got the problem of not being able to compare it to nil or even have a comparison in the sharedInstance method to prevent from overwriting the singleton. How to prevent from overwriting would be my followup question? I even tried it with another BOOL which I set to true during the init. The result is, the if (!bool) will be seen as true although my debugger says bool==yes-> !bool should be false.  THE QUESTION: Why is my pointer to the instance returned properly and outside (on the caller methods side) results to nil? To make it clear a call from outside:  ControlSchemes *cs = [ControlSchemes sharedInstance];   will enter the code of sharedInstance have a valid pointer to a valid object in the return according to the debugger BUT will then have nil inside the cs after stepping over. Why?   //


How can one cite theorems of references?

I would like to cite the item (iii) of proposition 3 of a reference. How can I do it? Which ways do you suggest? This is a question not only about LaTeX, but also about style. One option I have seen to cite pages of a reference is \cite[p.~333]{Audet}. Is there something similar to cite theorems, propositions and so on?


Use Existence Theorem to determine if $x = \frac{1}{4-t^2}$ yields a solution/s to $\frac{dx}{dt} = 2tx^2$. If so, give them.

I believe this is not a duplicate because the $D$ is different.       The problem: Does      $$x = \frac{1}{4-t^2} \tag{*}$$      yield a solution/s to      $$\frac{dx}{dt} = 2tx^2 \tag{**}$$      If so, give all maximal solutions together with their intervals of definition.        Definition: Let $x = x(t)$. A solution of the first order ODE $x' = f(t,x)$, where $f$ is defined on some domain $D \subseteq \mathbb R^2$ s.t. $D$ is open and connected, is a differentiable function $\varphi$ on some interval $I \subseteq \mathbb R$ s.t.         $(t, \varphi(t)) \in D \ \forall t \in I$   $\varphi'(t) = f(t, \varphi(t)) \ \forall t \in I$           Existence Theorem: If $f$ is continuous on a domain $D \subseteq \mathbb R^2$ and $(\tau, \xi) \in D$, then $\exists$ a solution $\varphi$ of $x' = f(t,x)$ defined on some interval $I$ s.t. $\tau \in I$ and $\varphi(\tau) = \xi$     What I tried:  1. On the choice of D  The denominator vanishes when $t = 2$ or $-2$ so I guess we can't say $D = \mathbb R^2$. How about  $$D = \{(t,x) | t > 2 \}$$  or  $$D = \{(t,x) | 2 > t > -2 \}$$  or  $$D = \{(t,x) | t < -2 \}$$  Are any open and connected? We didn't have any topology courses, and our real analysis only covered $\mathbb R$.    2. On existence  $f = 2tx^2$ is continuous on $D = \{(t,x) | t < -2 \}$ (I'm assuming this is right)  Choose $\xi = 10$ and $\tau = \tau^{10}$ where $x(\tau^{10}) = 10$.  Then $\exists$ a solution $\varphi$ of $x' = f = 2tx^2$ defined on some interval $I$ s.t. $\tau = \tau^{10} \in I$ and $\varphi(\tau^{10}) = 10$    3. On the choice of I  I differentiated $(*)$ to get $(**)$.  The denominator vanishes when $t = 2$ or $-2$ so I think the solutions are:  $$\varphi_1(t) = \frac{1}{4-t^2} \ on \ I = (2, \infty)$$  and  $$\varphi_2(t) = \frac{1}{4-t^2} \ on \ I = (-2, 2)$$  and  $$\varphi_3(t) = \frac{1}{4-t^2} \ on \ I = (-\infty, -2)$$    Is that right?    For another problem  $$x = \frac{2}{1-e^t}, \frac{dx}{dt} = \frac{x(x-2)}{2}$$  do we similarly have  $$\varphi_1(t) = \frac{2}{1-e^t} \ on \ I = (0, \infty)$$  and  $$\varphi_2(t) = \frac{2}{1-e^t} \ on \ I = (-\infty, 0)$$  For what $D$? $D = \{(t,x) | t < 0 \}$ okay? How about $D = \{(t,x) | t > 0 \}$?


Dynamically color labels in color of features (QGIS 3.x)

How do I dynamically color labels in the color of the labeled feature?  As you can see in the screenshot, the lines are in different colors, but the labels are just in black. As I know, I have to set the label color manually to get my expected result. But is there also a dynamic way to do so? Surely there is, because it‘s QGIS! But I don‘t know how. Any Ideas?


I'm downloading an engine game file which is compressed as .tar.bz2.  I'm trying this command  tar -zxvf enginsxt.tar.bz2   And it throws an error. I know that command  tar -zxvf   is only for extracting .tar.gz files, but how can I decompress this one?


Convergence of $\lim_{x \to 0}\frac{x - \sin{x}}{x^3}$

Without using  L'Hôpital's Rule or the Taylor Series expansion for the sine function, I would like to show that the function $$\frac{x - \sin{x}}{x^{3}}$$ has a limit at $0$. I understand that if it is assumed that the function has a limit at $0$, the limit must be $1/6$.


Difference of Community Wiki Edit and Normal Edit

Is there any difference between community wiki editing and normal answer editing. I can edit any question with just having 31 reputations so what does community wiki do except making restrictions for being edited by people under 100 reputations?


Whats the best way to install Ubuntu on a Samsung Chromebook?

I have been wondering what's the best way to install Ubuntu, on a Samsung Chromebook 2   Specification: Intel Celeron with 2GB of RAM and 16 GB of flash storage.  I am really not sure if that will be enough space for Ubuntu. I want to run my Linux games on here, then I realized it can't really do much. I am just a geek that wants to tinker with his hardware and operating system. And mostly because I want to use Ubuntu on the go, without using crouton. Even though it would void my warranty, but at the same time I don't want to brick my Chromebook since I just got it 2 weeks ago I somewhat enjoy Chrome os but I need my Ubuntu


Why won't Google use my meta description?

I have an issue with my website: Google isn’t using my meta description, instead it’s using the content of the web page and I’m really confused.  Reason I’m confused is because I have checked and I don’t have duplicate page titles, description nor keywords, neither do I have any robots.txt for my website. My page title, description and keyword is unique, and page description is about 150 characters.  I have my site in Google Webmaster Tools and I checked for errors, but found none.  So I really don’t know why Google Search isn’t using my meta description.


What exactly happens during the reflection of light at the atomic level?

I studied in Ray Optics that light either reflects, refracts or gets absorbed when it encounters another medium. But what exactly happens at the atomic level during reflection, refraction and absorption? At the macroscopic level, we see that light is reflecting, refracting or getting absorbed. But what happens at the atomic level when these phenomenan occur? Also, how can we decide whether light will reflect, refract or get absorbed when it encounters another medium. When exactly do these phenomenan take place? Please answer these two questions. I have been having these question since Grade 7 and now I am in Grade 12. I am so confused. Would greatly appreciate if someone could answer my above two questions.


Reflection and absorption of light at atomic level?

How does reflection and absorption of light work at atomic level? When does light pass straight through?Can anyone explain in detail please?


character in my blender is Low quality    but in the render is:   I want render quality = quality in 3D view


How do you transfer videos to iTunes/iPod?

I have a load of videos from my old Walkman that I transferred to my new computer, and want to put them on to the iPod I bought as a replacement MP3 device.  When I press the "Add File/Folder to Library" and select one of these videos, nothing happens, and they don't show up in any folder, and can't be found on the iPod once synced.  How do I do put the videos on my iPod?


The best part of me is my hands. or The best part of me are my hands.


How did LIGO scientists determine the source of the gravitational waves they detected?

I read the newspaper today and I found that LIGO had detected gravitational waves. This is from their official website:     For the first time, scientists have observed ripples in the fabric of spacetime called gravitational waves, arriving at the earth from a cataclysmic event in the distant universe. This confirms a major prediction of Albert Einstein’s 1915 general theory of relativity and opens an unprecedented new window onto the cosmos.   How did they know the source of the gravitational wave was a binary black-hole merging event? Wikipedia says:     Measurable emissions of gravitational waves are expected from binary systems (collisions and coalescences of neutron stars or black holes), supernova explosions of massive stars (which form neutron stars and black holes), accreting neutron stars, rotations of neutron stars with deformed crusts, and the remnants of gravitational radiation created by the birth of the universe.   There are more possible sources. Can the LIGO detect black holes as well?


Can an 85w MagSafe charger (model#: A1172) be used safely with a MBPro 13.3” retina?

I’ve read through a few threads on here on this subject - which give very detailed information - but just wish to ask, by way a safety/ sanity check, the following...  I have a MacBook Pro 13” Retina display (early 2013), which uses a Magsafe 2 60w charger.  The original, 60w charger has failed and I wish to confirm whether this charger I have will be safe to use with my MB Pro:   Apple 85w MagSafe charger for MacBook Pro.  Model#: A1172 Input: 100-240V-1.5A 50-60Hz Output: 18.5V 4.6A   Link:   I have this from an earlier model MBPro I had.  If I wire this up, by soldering a Magsafe 2 replacement power cord to the board, will this work safely with the MBPro 13”?  Despite the info’ on other threads here confirming that it’s fine to use a 85w MagSafe with a mac that normally uses a 60w charger, I’m unsure whether this one will be safe due to it being an older model than those refered to; ie. older, larger/ rectangular model rather than the more recent square ones.  Would this be safe/ compatible despite this?  Thanks greatly for any help with - best wishes, AE


How do major and minor grooves arise in the DNA helix?

I understand that they arise due to the pairing of bases of two opposite stands and are sites through which important proteins needed for replication and transcription of DNA interact. But I don't get how the arrangement of bases really generate the grooves.


How can I retrieve a set of table names which hold certain value?

For an example I have 100 tables (table1,table2,table3,table4 and table5.....) in my DB, table1 with the coloumns col1, col2...col7 like wise every table has some columns. The column col7 have the value 'BOLD'. Here I want to retrieve the tables which holds the value 'BOLD'.


I installed CyanogenMod 11 on my HTC One with CyanogenMod Installer. So I got also the google Apps (gapps) on my device. But I need a CM11 without gapps. I did then the following without success:   copy cm-11-20140308-SNAPSHOT-M4-m7.zip to /sdcard/ boot to recovery mode -> recovery -> ClockworkMod Recovery v6.0.4.6: "wipe data/factory reset" "install zip" choosing the zip-file "reboot system now"  So I got a new CM11 but with gapps still installed.  What should I do in addition to "wipe data/factory reset" to get rid of this apps?


Where should questions about deployment, versioning and rollout be asked?

There are lots of questions that come up when thinking about getting software productive.   Like how to do versioning of the software, how to deploy it on client side and generally how to roll software out.  Having done this multiple times in different ways, there are still lots of open questions.  If I ask them on stackoverflow, they will get closed with very high probability. They are not to programming related, I cannot provide code, they seem to be  ideally suited for "off topic".  So: Where can I ask those questions?  -edit-  To have more concrete example of the questions that I would like to ask:   What to consider before rolling software out? How to version a bunch of assemblies without having to edit lots of config files? How to keep software on client side up to date? ...   I would really appreciate to ask those questions myself, if there is a place for it somewhere. SO seems to be no match.


How do i install ubuntu from usb from scratch?

I want to install ubuntu from a usb from startup. without having windows already installed.


I have installed Skype in Ubuntu, but I do not know where to start the installed the Skype application .Similarly  I have installed Netbeans and other applications but their icons are not appearing in any menus.  Related: how to uninstall already installed applications?


What is the correct form in the following sentences, "both" and "both of them"?      a) "Both of them are unique."      b) "Both are unique."   If "both" by itself already contains "both of them", so I can conclude that the first option is not correct. Isn't it?


In App Store app, if I search for a word.  What does the returned listing order of apps base on?  Let's say, it returned app1, app2, app3, ..., app10.  What was the listing order based upon?


Modelling when the dependent variable has a "cut-off"

Apologies in advance if any of the terminology I use is incorrect. I'd welcome any correction. If what I describe as a "cut-off" goes by a different name, let me know and I can update the question.  The situation I'm interested in is this: you have independent variables $\bf{x}$ and a single dependent variable $y$. I'll leave it vague, but assume that it would be relatively straightforward getting a good regression model for these variables.  However, the model you're aiming to create is for independent variables $\bf{x}$ and dependent variable $w = \min(y,a)$, where $a$ is some fixed value within the range of $y$. Equally, the data you have access to does not include $y$, only $w$.  A (somewhat unrealistic) example of this would be if you were trying to model how many years people will collect their pension for. In this case, $\bf{x}$ could be relevant information such as gender, weight, hours of exercise per week, etc. The 'underlying' variable $y$ would be life expectancy. However the variable you'd have access to and be trying to predict in your model would be $w = \min(0, y-r)$ where r is the retirement age (assuming for simplicity it's fixed).  Is there a good approach for dealing with this in regression modelling?


From the fact that the Lian Yu is somewhere in the Pacific, we can assume that the Queen's Gambit left from the west coast of the United States.   While it is never specified, it is heavily implied that the port the Gambit left was in or very near Starling City, as Sara was shown to have been visiting home the night before the trip, and went on the trip in secret.   In City of Blood (S02E21), Felicity mentions that she moved 1000 miles from Las Vegas, presumably to go to school in Starling City.   Where is the fictional Starling City located?


What is needed -by definition- to determine the shortest (Euclidean) distance between two parallel lines in the x,y plane? I am thinking if someone can write this down (mathematically) beautifully covering both knowing the equations of the lines or the coordinates of two points lying on the lines.


What does ~ in front of the class name signify in C#?

Let's assume there is a class like this:  public class NewClass : IDisposable {   public string name {get; set;}   public NewClass(string Name)   {     name = Name;   }    ~NewClass()   {     Dispose(false);   }     public void Dispose()    {     Dispose(true);     System.GC.SuppressFinalize(this);    } }    What does the ~NewClass() mean here? When and why to use expressions such as "~NewClass()" ()) inside a class? .... and how would it help?


Why my regex is not working in react but working anywhere else (e.g. regex tester online)?

let titles = this.state.posts.slice(0, 3).map(function(title, index) {   let regex = /


Why does my DIY "solar panel circuit" show battery voltage and not solar panel voltage?

I have six solar panels but each are different from one another. The first is 4.5V. The second is 6V. And the last four are all equal up to 6V. It all adds up to 16.5V in series or on a good sunny day, 18V max. That's what my multimeter says.  I have a 1N1914 diode connecting to the positive lead connecting to my double pull switch. Now for my batteries, I have one 9V rechargeable battery and 4 AA (1.2V each) rechargeable batteries. The batteries total to 13.8V.  When I try to charge my batteries, it doesn't charge any of it. The switch actually works fine. But when I try to charge the batteries, the meter shows my battery voltage rather than my solar panel. What am I doing wrong?


How do I get my camera to go on in Pokemon go?

On Pokemon go I can't seem to get off of the map. I want the screen to turn into my camera so that I can catch the Pokemon. How do I do it?


My 5e character isn't very fun. How do I kill them off?

I'm playing an 8th level Valor bard, and she's basically  (warning: TVTropes link) at this point- high-combat campaign, so not a lot of charisma stuff to do, and really doesn't have any casting function that the others can't do better. Her motivation is to find and defeat challenges, and has a tendency to think she can do more than she can, which is how she wound up as The Load in the first place, so getting killed off by something she couldn't handle would be a very in-character end.  However, my party is pretty heal-happy (8th level druid, ranger and paladin) and it would be in character to heal her. That, combined with the 3 death save mechanic, makes it pretty difficult to kill the character off. How do I get around this so I can roll up a character with some actual utility?


Excel freezes when copying / cutting to paste elsewhere

When cutting/copying some cells to paste them into another sheet/page, sometimes Excel freezes/locks up and fades out. At the top toolbar it says in brackets "not responding".  Eventually, I must click 'X' to close the program. It offers to wait for the program to respond, but never does – it just does nothing until I finally close it, where it offers to recover files etc.   Is there an issue with memory here? What can I do to stop it locking up?


Partitioning the Reals into two Locally Uncountable, Dense Sets

Is it possible to find two disjoint subsets $X$ and $Y$ of $\mathbb{R}$ such that both are dense in $\mathbb{R}$ and both are locally uncountable?  By a locally uncountable set $X \subset \mathbb{R}$, I mean a set which has the property that if I take any nonempty open subset $U$ of $\mathbb{R}$, then $U \cap X$ has cardinality strictly larger than the natural numbers.


How to remove all files in a directory except hidden ones?

I'm cleaning an output directory before I put things in it.  I want to track the output directory in git with a .gitkeep file, but this keeps on getting deleted with my rm -rf "$OUT_DIR" line in a bash script.  Is there a way to remove the contents of a directory but keep either hidden files or somehow just keep that .gitkeep file?


I am getting the above error when i run the command:  apt-get -f install   E: Could not open lock file /var/lib/dpkg/lock-frontend - open (13: Permission denied) E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), are you root?    How can i overcome this?


He has been buried 4 days or for 4 days?

I have read this sentence and I'm not sure that it's correct He has been buried 4 days I think it should have been He has been buried for 4 days. Am I correct?


Fermat's little theorem and its generalization, Euler's theorem holds for pair of relatively prime integers. Are there any analogous results for not relatively prime integers ? Thanks in advance.


Definition of effective potential energy in two-body central-force problems

The Lagrangian of the two-body problem in terms of polar coordinate $r$ and $\phi$ is $$\mathcal{L}=\frac{1}{2} \mu (\dot{r}^2+r^2\dot{\phi}^2)-U(r)$$ And the Lagrange equation corresponding to $\phi$ is a statement of conservation of angular momentum $$\frac{\partial \mathcal{L}}{\partial \dot{\phi}}=\mu r^2 \dot{\phi}=const=l$$ If I use this equation to eliminate the $\dot{\phi}$ in the first equation, I'll have $$\mathcal{L}=\frac{1}{2} \mu \dot{r}^2+\frac{l^2}{2\mu r^2}-U(r)$$ We can define $U_{eff}(r)=U(r)-\frac{l^2}{2\mu r^2}$ so that $\mathcal{L}=\frac{1}{2} \mu \dot{r}^2-U_{eff}(r)$  However, in Taylor's book Classical Mechanics, he first looks at the Lagrange equation corresponding to $r$ (or radial equation) $$\mu r \dot{\phi^2}-\frac{dU}{dr}=\mu \ddot{r}$$ Then define centrifugal force as the first term in LHS $$F_{cf}=\mu r \dot{\phi}^2= \frac{l^2}{\mu r^3}=-\frac{d}{dr}(\frac{l^2}{2 \mu r^2})= -\frac{d U_{cf}}{dr}$$ Return to the radial equation, we have $$\mu \ddot{r}=-\frac{d}{dr}[U(r)+ \frac{l^2}{2 \mu r^2}]=-\frac{d}{dr} U_{eff}(r)$$ It seems that $U_{eff}(r)=U(r)+\frac{l^2}{2 \mu r^2}$ in Taylor's book, instead of $U_{eff}(r)=U(r)-\frac{l^2}{2\mu r^2}$ as we got previously.  I'm quite confused that why I get a minus sign in the definition of $U_{eff}(r)$ if I look directly at the Lagrangian, using the statement of conservation of angular momentum. I wonder I have this minus sign because I change the form of Lagrangian too early but I can't figure out why I can't do it.


I'm stuck... The problem states that - You wish to construct a right cylindrical can (with bottom and top) from a square steel plate with side length 10 cm. What dimensions on r and h maximizes the volume of the can.  Can someone please point me in the right direction.


Difference in meaning between "booking is amended" and "booking has been amended"

What is the difference in meaning between "booking is amended" and "booking has been amended"?


How to prove that set A is Lebeg measurable?

I'm wondering how to solve this. We have an infinite countable set A ⊂ R is such that λ * (A) =0, . I would appreciate any help. Thanks.


If $\beta$ can be expressed $\frac{\text{cov}(Y, \widetilde X) }{\text{var}(\widetilde X)}$... So where does the shared component of the variance go?

I think this is a fairly technical, conceptual question so I'm going to do my best to explain what I'm thinking. For the regression $\widetilde Y = \hat \beta_0 + \hat \beta_1 X_1 + \hat \beta_2 X_2$, the equation for the coeficient $\hat \beta_2$ is $\text{cov}(Y,\widetilde X_2)/\text{var}(\widetilde X_2)$ where $\widetilde X_2$ are the $e$'s from the regression $X_2 = \hat \beta_0 + \hat \beta_1 X_1 + e$. Conceptually, these errors are the variance of $X_2$ that can't be explained by the other covariates, up to an affine transformation. Thus, only the "unique variation" in $X_2$ is what gives us additional power in predicting $Y$. The same can be said of $\hat \beta_1$ and $X_1$. What I'm trying to understand is what happened to the parts of the variance that were similar in $X_1$ and $X_2$? By similar I just mean that $X_2$ could explain in $X_1$ and what $X_1$ could explain in $X_2$. It seems like it needs to show up somewhere in the regression results but I can't find where it is... I think it'd end up in the $\hat \beta_0$ but I'm not sure if that's accurate or how to show it.


How to get v4l2 loopback device to be recognized?

I am trying to set up a greenscreen effect for a video conference in Google Meet, which runs in a web browser, in this case Google Chrome.  As an initial test I have set up a V4L2 loopback device and am feeding it a video as outlined in .  However, when I go to select the device, I only see the build-in webcam, with no option for the second video source I have added which is showing up as /dev/video2.  I also went to chrome://settings/content/camera and it is not showing my new video source.  I also tried restarting Chrome, but it still does not show up.  I am able to run ffplay on /dev/video2 and it shows my video, so I know that part is working!  How do I get Google Chrome to recognize my second video source?  (Running Ubuntu 18.04 LTS)


In the Wizard of Oz (the movie version) the Good Witch of the North, Wicked Witch of the West and Wicked Witch of the East are all mentioned.   Was there ever a Witch of the South?


Learning Roadmap to Mathematical Physics

Currently, I am a graduate student specializing in algebraic geometry. On the other hand, I have also become extremely interested in the mathematical physics. However, I am not sure what steps I should take to get to the modern frontiers of mathematical physics research. My mathematical knowledge covers basic graduate analysis, algebra and topology with an emphasis in algebraic geometry, and as for physics, I know up to basic quantum field theory at the level of P&S and basic general relativity at the level of Wald.  However, unlike those fields that I have studied so far, I am not sure what to learn in order to learn the basics to get to the research level, i.e., able to fully comprehend and dissect research papers in the mathematical physics journals. Most mathematical physics books that I have seen so far are only mathematical methods used in physics. To re-emphasize, I don't simply want references of mathematics used in physics, I wish to know the fundamentals that mathematical physics have to master and concrete examples of modern topics in the field. However, if it is essential, I would like to know what the main relevant mathematical topics are.  I suppose one of the main things I'm confused about is, before one does any actual research, what exactly is the difference between the training/preparation for a mathematical physicist and a pure mathematician? It seems that mathematical physicists basically just learns mathematics, except it's not focused in a particular field and has some physical applications.Do mathematical physicists often get insights behind the way a physicist thinks about problems as well?  Thus, for my main question: What specific books/papers should I start reading to understand the fundamentals of mathematical physics at this point and in what order should I read/study them?  As for side questions: I do not really understand the basic knowledge that a mathematical physicist should have. Do they specialize in a particular area of mathematics or is it mostly topology and geometry or must they know other applicable areas such as functional analysis as well and to what depth?  Would me continuing to self-study algebraic geometry be compatible with learning mathematical physics at the same time? What main fields are there now and what advanced books/papers could I read regarding them after learning the fundamentals as addressed in my previous question? What are the most relevant mathematical topics? Off the top of my head, I can think of mostly functional analysis and topology and geometry.


Sugar daddy wants to transfer me money for me to buy him gift cards

I’ve been talking to a sugar daddy for a couple days and he wants to mobile transfer me 200$. He wants me to buy 150$ worth of google play gift cards for him and then keep 50$ for myself. Is this a scam?


How can I retrieve mp3 metadata in Python?


Setting display to reduce migraines, what does nomodeset and fbdev mean? and how to set them?

In a forum about migraines and computer displays, i've found these instructions:"and try nomodeset for intel kernel module i915 and the fbdev video driver. It's basically the same thing as Standard VGA in Windows 7."   What does those mean ? how do i achieve them in ubuntu ?


How to securely wipe my SSD before reinstalling an encrypted Ubuntu?

I think I didn't encrypt my drive when I installed Ubuntu and I would like to use the opportunity to change that when I install Ubuntu 20.04. I'd like to make sure that all data is permanently wiped before I do a fresh installation, but that's turning out to be a bit of a problem. All I found online on the topic was the advice to go on the manufacturer's website to see how to proceed.   I have a Samsung 970 EVO SSD, and the tool that Samsung offers (Samung Magician) appears to be available exclusively for Windows. Any ideas how to get this done?


Is there a site or way to output all of the permutations of a regex pattern?  I made a simple pattern here with desired output from this 'app':    or see below:  (?<TERM>(Big |Small )(Brown |Green |Red )(Ball|Box))    Big Brown Ball Big Green Ball Big Red Ball Small Brown Ball Small Green Ball Small Red Ball Big Brown Box Big Green Box Big Red Box Small Brown Box Small Green Box Small Red Box


Do you a digit efficient way to approximate $\pi$? I mean representing many digits of $\pi$ using only a few numeric digits and some sort of equation. Maybe mathematical operations also count as penalty.  For example the well known $\frac{355}{113}$ is an approximation, but it gives only 7 correct digits by using 6 digits (113355) in the approximation itself. Can you make a better digit ratio?  EDIT: to clarify the "game" let's assume that each mathematical operation (+, sqrt, power, ...) also counts as one digit. Otherwise one could of course make artifical infinitely nested structures of operations only. And preferably let's stick to basic arithmetics and powers/roots only.  EDIT: true. logarithm of imaginary numbers provides an easy way. let's not use complex numbers since that's what I had in mind. something you can present to non-mathematicians :)


Booking.com cancellation fees during COVID-19 outbreak?

I booked an apartment in Barcelona for the 19th March, but obviously I’ll be unable to attend due to the coronavirus.   I have paid for the apartment up front, in full.   I messaged the apartment owner on booking.com regarding a potential refund.  I got a message back saying I’d have to request to cancel the booking for free and then go from there?   Why would I have to do this? I’ve paid up front, so why is there a cancellation fee?  Also, is there any chance of me getting a refund?


What weapons should I use to battle the Destroyer?

I have tried to kill the Destroyer a couple of times. The first time I built the arena it killed me and I went back to my spawn point. It followed me and killed all of my MPCs. I don't use guns very much because I have terrible aim. I have a adamintite sword and mythril armor. What different kinds of weapons should I use since these are not working for me?


Autocomplete username references in answer posts

It would be nice if the @username autocomplete idea for comments could be extended to answer posts. Although, what I'd really like to see is a faster way to reference other people's answers to a given question, within your own answer. Say user 'foo' already posted an answer. I would like to provide a link/credit to foo's answer within my own answer. As it is right now, the only way (that I know of) to do this is by copying the link to their answer and creating a link within my answer. It would be a small time-saver if the @username notation could be used to do this instead, such that @foo would be automatically expanded to a link to foo's first answer in the current question.


Consider this example:  \documentclass{article} \usepackage{graphicx}                                              %\usepackage[latvian]{babel}                                                     \renewcommand{\figurename}{att.} \begin{document} \begin{figure}   \includegraphics{example-image-a}   \caption{cap} \end{figure} \end{document}   \renewcommand{\figurename}{att.} fails once I uncomment the line   \usepackage[latvian]{babel}.   The purpose is to override the settings in babel.   How to solve this problem?


Difference in meanings for English past tense

Do they all mean the same thing, or are there any technical differences?  I worked at McDonald's. I used to work at McDonald's. I had worked at McDonald's.


Is there a rational number between any two irrationals?

Suppose $i_1$ and $i_2$ are distinct irrational numbers with $i_1 < i_2$.  Is it necessarily the case that there is a rational number $r$ in the interval $[i_1, i_2]$?  How would you construct such a rational number?  [I posted this only so that the useful answers at  could be merged here before that question was deleted.]


How do you use the ellipsis slicing syntax in Python?

This came up in  , but I can't see good documentation or examples that explain how the feature works.


Install Ubuntu 13.04 on Sony Vaio E Series SVE14125CNB

Please help me to install Ubuntu 13.04 in a dual boot setup with Windows 8 on my Sony Vaio E Series SVE14125CNB laptop. When I try to install Ubuntu, after the installation is finished, the system gives me a message that says: operating system missing. Then I changed the BIOS setting as normal, and it only boots Windows 8.


Textbook on the Geometry of Special Relativity

I am looking for a textbook that treats the subject of Special Relativity from a geometric point of view, i.e. a textbook that introduces the theory right from the start in terms of 4-vectors and Minkowski tensors, instead of the more traditional "beginners" approach. Would anyone have a recommendation for such a textbook ?  I already have decent knowledge of the physics and maths of both SR and GR ( including vector and tensor calculus ), but would like to take a step back and expand and broaden my intuition of the geometry underlying SR, as described by 4-vectors and tensors. What I do not need is another "and here is the formula for time dilation..." type of text, of which there are thousands out there, but something much more geometric and in-depth.  Thanks in advance.


IMO/1981 Let $1\le p \le n$ and consider all of the subsets of $p$ elements of the set $\{1, 2, 3,..., n\}$. Each of these subsets has a minimum element. Let $F(n, p)$ be the arithmetic average of these minimum elements. Prove that $F(n, p) = \frac {n+1}{p+1}$ My attempt: So i initialy tried to think about how many subsets can you have given a minimum value $k_m$, such that $k_m \in \{1, 2,..., n\}$ obviously, but also such that $k \le n - p$, because otherwise that would mean the set can't have a minimum value of $k_m$ and $p$ elements, because that would mean you have less options to construct the set from ( $n - k_m  - 1$)  than you are needed ($p-1$). So i figured that if i fix a $k_m$ i have ${n - k_m - 1} \choose{p - 1}$ different sets in which this fixed element is the minimum, so the arithmetic average asked in the question is equal to: $$F(n, p)=\frac{\sum_{k=1}^{n-p} k \binom{n - k - 1}{p - 1}}{\sum_{k=1}^{n-p} \binom{n - k - 1}{p - 1}}$$ So i need to prove that: $$\frac{\sum_{k=1}^{n-p} k \binom{n - k - 1}{p - 1}}{\sum_{k=1}^{n-p} \binom{n - k - 1}{p - 1}}=\frac{n+1}{p+1}$$ But i'm struggling to effectively attack this proof simply because this sum is unlike any other one i've proven before, so i'd like to know: If my reasoning has been correct so far (and if not, why not?) , and also some ideas on how to prove that huge sum.


Lubuntu refuses to boot from HDD despite numerous tries with boot-repair

I remember problems setting up my Lubuntu with UEFI/Legacy boot mode. That was more than a year ago and the system worked fine - until now. For whatever reason, it refuses to boot again.  I went through a number of different recipes involving boot-repair, but it still won't boot. The paste from boot-repair can be found here .  My approach was to format my EFI partition again in FAT32 and assign the boot flag to it before running boot-repair. In boot-repair > advanced options > GRUB location, I cannot select my EFI partition (sda1) in the field 'separate /boot partition'. However, it does not complain about not finding the EFI partition. The EFI partition (sda1) also shows up in the /etc/fstab (sda4), after running boot-repair:  # <file system> <mount point>   <type>  <options>       <dump>  <pass> # / was on /dev/sda4 during installation UUID=85ae8106-d4ae-49ee-9e77-e93aa86c6e63 /               ext4    errors=remount-ro 0       1 # /boot/efi was on /dev/sda1 during installation #UUID=D954-89D5  /boot/efi       vfat    defaults        0       1 # /home was on /dev/sda5 during installation UUID=ffc890d1-0cd6-4a5b-86c3-b6c8db17a1e1 /home           ext4    defaults        0       2 # swap was on /dev/sda3 during installation UUID=507de4f4-fde7-4c5b-badd-66defcbc27f5 none            swap    sw              0       0 #UUID=d2bb4e60-b497-4cd4-8b8c-04ffe5f3085a  /boot   ext4    defaults    0   2   In my BIOS, however, I do not find any boot loader that uses UEFI.   I would appreciate any help on this issue.  Thanks, Michael  EDIT  I went foward and installed , which boots, but doesn't find Lubuntu either...  SOLUTION  I discovered this post , which describes how to do the BIOS/UEFI conversion. Apparently, this works for me.


I am currently on season 3 of Star Trek: TOS, and wanted to know if/how watching in this order will affect the story (NO SPOILERS PLEASE!!!):  Star Trek: TOS Star Trek: TAS Star Trek movies 1-7 Star Trek: TNG Star Trek movies 8-10 Star Trek: DS9 Star Trek: VOY Star Trek: ENT  If there is a problem please say how I should watch instead. Thanks!


All these days, I was using the below code to get any value from web config.  string someValue= WebConfigurationManager.AppSettings["SomeKey"]   When I came to know that  and it was explained there that   ...First of all in ASP.NET you want to ensure you access configuration sections through the   HttpContext object's GetSection method (this uses the cached copies managed by ASP.NET)...   Is WebConfigurationManager.AppSettings will always fetch value from web config and not from cache? If Yes, How do I fetch config value from cache?   P.S How caching works with app.config? Is it stored on windows RAM or .. ?


Bold subscripts with \bm changes sans to serif

Let us assume I have some equation like  \documentclass{article}   \usepackage{cmbright}  \usepackage{amsmath}  \usepackage{bm} % boldmath  % ******** \begin{document}  bold not working: \begin{equation}     X_\mathbf{n} \end{equation} Let us try bold here: \begin{equation}     p_{\bm{n}} \end{equation}  \end{document}   The problem with that command is, that it changes the font from sans to serif. Strange, isnt it? It leads also to a lot of confusion.  Any ideas?


What is the reasoning for the idiom "in and of itself" having the meaning it has?

"In and of itself" is a phrase I find myself using all the time. But in and of itself, the phrase "in and of itself" has no meaning. That is, the individual words don't seem to contribute to the whole meaning of the phrase.


What US state does Katniss Everdeen live in?

The Hunger Games says that the remains of the U.S. are 12 districts. But where are they placed? What states?


In soccer, players often exaggerate their injuries to make their opponent look more guilty.   I've also seen this on TV shows with a hostile police officer, saying things like "Whoa whoa whoa, calm down, sir." after the person with whom they are speaking says something innocent.  The idea is exaggerating a response to make it seem like there was aggression that would have merited such a response.  Is there a succint term or phrase for that?


How to decompose tensor products of $SU(3)$ representations?

Formally, one can arrange the quark flavors in a $SU(n)$ fundamental representation. One can then do tensor products for flavor and spin to construct other representations like baryons and mesons. An example: $2⊗2=3⊕1$ for spin $SU(2)$ gives scalar and vector mesons, $3⊗\overline3=8⊕1$ for flavor $SU(3)$ gives the eightfold way for both scalar and vector mesons. My question is easy: how do you get $3⊗\overline3=8⊕1$? Or for baryons: $3⊗3⊗3=10⊕8⊕8⊕1$?


Down votes should not have any side effect, on meta

After my , I've now got a new suggestion: down votes should not have any side effect in meta.  By side effects, I mean something like banning me from asking questions due to too many down votes, which I am experiencing right now:     states that I am permanently banned unless I improve my standing by posting some quality answers.  Seriously, I'm new to the site, and thus I'm not capable of posting quality answers on Meta.  So my only refuge was to create a new account. I think this check for previously downvoted posts should be disabled on Meta.


How did Neo know that the "reality" Morpheus told him was the real world was not actually just another simulated reality? I mean if he believed Morpheus' explanation on simulation isnt it logical for him to assume that the real world was also simulated. Wouldnt it be the perfect prison designed by the machines. Design the prison world and a world for those who think they have escaped.


I have a form that sends datas to my DB. However I want to make sure it is safe. I used to use htmlspecialchars($variableToSecure) But I learned it is not enough (protects only from html injections) I searched on internet and found mysql_real_escape_string($variableToSecure) But this one is obsolete and doesn't exist since php 7.0 I wish to know what is the best way to secure a variable now?


Do I get more candies if I sent back evolved Pokemon to the professor?

Currently, any duplicate Pokemon with a low combat score I find, I'll send back to the professor for candies to evolve my high ranking ones.  Yet I wonder if I should evolve some of them first with candies and sent them back then. Is there a bonus of sending back evolved pokemon in regards of candy? Or would it be a waste of resources?