Mute sound after a certain time for Windows?

Is there a way I can automatically disable sound on my PC after a certain time?   Scenario: I go to sleep. Someone calls me on Skype or my Gmail Notifier plus application makes an alarm notification for new email.   Intended use-case: PC is still running as I forgot to put it into sleep mode Since it is now after 11:00 PM, any sounds are muted.


I know that there is no vector space having precisely $6$ elements. Does every set have a group structure?


I can't send email via my own Postfix anymore due to enforced restrictions that I made

Until recently my server with Postfix has worked well. Then I enforced some restrictions to a) combat spam b) disable sending emails to me on behalf on my own name -- I have begun receiving emails from my own email address demanding to send bitcoin to someone.   I want to fix both a and b.  And now I can't send email via my own postfix server.    Client host rejected: cannot find your reverse hostname, [<my ip here>]   Note that I carry my laptot to different places and countries, and connect to WiFi from those. And I want to be able to send email always.  Here's a part of my config of Postfix. For database of the accounts and domains I use Postgresql.  smtpd_helo_required = yes  smtpd_client_restrictions =   permit_mynetworks,   permit_sasl_authenticated,   reject_unknown_reverse_client_hostname,    reject_unknown_client_hostname,   reject_unauth_pipelining  smtpd_helo_restrictions =   permit_mynetworks,   permit_sasl_authenticated,   reject_invalid_helo_hostname,  ###  reject_non_fqdn_helo_hostname,   reject_unauth_pipelining  smtpd_sender_restrictions =   permit_mynetworks,   reject_sender_login_mismatch,   permit_sasl_authenticated,   reject_non_fqdn_sender,   reject_unknown_sender_domain,   reject_unauth_pipelining  smtpd_relay_restrictions =   permit_mynetworks,   permit_sasl_authenticated,   reject_non_fqdn_recipient,   reject_unknown_recipient_domain,    reject_unauth_destination   smtpd_recipient_restrictions =   permit_mynetworks,   permit_sasl_authenticated,   reject_non_fqdn_recipient,   reject_unknown_recipient_domain,   reject_unauth_pipelining  smtpd_data_restrictions =   permit_mynetworks,   permit_sasl_authenticated,   reject_multi_recipient_bounce,   reject_unauth_pipelining  # deliver mail for virtual users to Dovecot's LMTP socket virtual_transport = lmtp:unix:private/dovecot-lmtp  #  query to find which domains we accept mail for virtual_mailbox_domains = pgsql:/etc/postfix/virtual_mailbox_domains.cf  # query to find which email addresses we accept mail for virtual_mailbox_maps = pgsql:/etc/postfix/virtual_mailbox_maps.cf  # query to find a user's email aliases virtual_alias_maps = pgsql:/etc/postfix/virtual_alias_maps.cf  virtual_alias_domains =  alias_database =  alias_maps =   mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 inet_interfaces = all


¡Hi everyone!  I have a question, let me introduce the problem:  "Let be $M$ a right $R$-module, and $I$ ideal of $R$,     if $I \subseteq Ann(M)$. Show $M$ has a natural structure like right $(R/I)$-module."  My two questions is:    What means "Natural structure" Why i need $I \subseteq Ann(M)$?   Thanks.


If statement is never True, cannot figure out why. Java

I'm writing a program for an assignment which I have to convert english to Klingon and I'm pretty sure all my code works except for the if statement in my method transToKlingon.  I cannot figure out why the if statement never is true.  import java.util.*; import java.io.*;  class transToKling {     public static void main(String[] args)      throws java.io.IOException     {               // Create array         String[][] klingTrans = new String[16][2];             String filName = " ";                filName = "klingonTranslate.txt";               Scanner input = new Scanner(new File(filName));               for (int row = 0; row < klingTrans.length; row++)               {                        for (int col = 0; col < klingTrans[row].length; col++)                                 klingTrans[row][col] = input.nextLine();               }              input.close();          Scanner sc = new Scanner(System.in);      System.out.print("Enter english phrase to translate to Klingon: ");      String phrase = sc.nextLine();       transToKlingon(phrase, klingTrans); }  public static void transToKlingon(String txt, String[][] klingon)  {     // split txt string and find search array for match.         String[] s = txt.split(" ");      for (String txtSplit : s)      {         for (int i = 0; i < klingon.length; i++)          {                                                                            if (klingon[i][0] == txtSplit)              {                                    System.out.print(klingon[i][1] + " ");             }         } // end i for     } // end for each txtSplit } // end transToKlingon Method   }


How would I access my list from Update function?

The DFT function below works fine but I want to use the list, generated from that function, in the Update function.  using System.Collections; using System.Collections.Generic; using UnityEngine;  public class FFT : MonoBehaviour {     public ArrayList amp = new ArrayList();     public ArrayList freq = new ArrayList();      void DFT()     {         float[]  X = {1, 2, 3};         float[]  Y = {2, 3, 5};         float  N = X.Length;          for(int k = 0; k < N; k++)         {             float re = 0;             float im = 0;              for(int n = 0; n < N; n++)             {                 float phi = (2 * Mathf.PI * k * n) / N;                 re += X[n] * Mathf.Cos(phi) + Y[n] * Mathf.Sin(phi);                 im += Y[n] * Mathf.Cos(phi) - X[n] * Mathf.Sin(phi);             }              var  freqq = k;             var  ampp = Mathf.Sqrt(re*re + im*im);             var  phasse = Mathf.Atan2(re, im);             phase.Add(phasse);              amp.Add(ampp);             freq.Add(freqq);          }     } }   I want to use the lists elements in another function (for example in Update)  void Update() {     for(var i = 0; i < 2; ++i)     {         var x = amp[i] * Mathf.Cos(freq[i]);         var y = amp[i] * Mathf.Sin(freq[i]);          var pos = new Vector3(x, y, 0);          //Debug.Log(pos);     } }   The problem is that amp[i] and freq[i] doesn't work in another function.


Prove that there are infinitely many primes of the form $4k + 3$ (where $k$ is an integer).   Note that it is a special case of "Theorem 6 (Dirichlet). Let a and b be positive coprime integers. Then the sequence $b$, $b + a$, $b + 2a$, $b + 3a$, $b + 4a$, $b + 5a$, ....," contains infinitely many prime numbers  So far I got that suppose there are a finite number of primes   $p......p$  and if $4(p.....p)+3$ is prime it's a contradiction so the initial statement is proven?


We all know what  numbers are. I was more interested in checking an efficient way to find nth non square free number.


"I was starting suspecting something was wrong" <-- What's the grammar problem here?

I have been using “starting suspecting” frequently thinking that it’s correct too but recently my friend corrected me. I don't understand why.  It is well-known that start to + verb and start verb-ing are interchangeable in terms of meaning:        It started to rain.   It started raining.      The sentences above mean the same thing.  There is also no problem with the verb suspect being used as a gerund-participle:  Consider:   I started suspecting something was amiss.   There is no problem with using the verb start in continuous cobstructions:   It was starting to rain.   So what's the grammatical problem with the folowing?        I was starting suspecting that something was amiss.


Why is the symmetry variation $\delta_s q$ different from the ordinary variation $\delta q$?

I was reading about symmetry of action when I came before the symmetry variation in Particles and Quantum Fields by H. Kleinert; there he wrote:     Symmetry variations must not be confused with ordinary variations $\delta q(t)$ used to derive the Euler-Lagrange equations. While the ordinary variations   $\delta q(t)$ vanish at initial and final times, $\delta q(t_b) = \delta q(t_a) = 0,$ the symmetry variations $\delta_s q(t)$ are usually non-zero at the ends.   So, isn't $\delta_s q$ a virtual variation? For, if it would be, it should have vanished in the fixed initial and final time, $t_a$  and $t_b$, isn't it?  Could anyone explain me why the symmetry  variation is different from the ordinary variation?


Simple quick DoF estimate method for prime lens

All:  I have a concrete example related question:  My prime len is Nikon 35mm f/1.8G DX. If I only use this lens to shoot, I wonder if there is any simplified Depth of Field estimate method like by using thumb or simple way of measure?   Thanks


How to remove or disable Ease of Access button on Windows 7 login screen

Question refers to Windows 7 Professional 64-bit.  When I lock my computer I don't want people to be able to mess about with it, so would like the Ease of Access button (in the bottom left corner of the logon screen) to either be removed or disabled.  Does anybody know how to do this?  Thank you for your help :-)


How can I export a Blender Animation as a Video?

I am a newbie to blender. As a part of my coursework I have to do an animation video. I have created  a model, rigged him but now I wonder how to export the animation (pose mode) as a video. There was no proper explanation on it in youtube,vimeo,dailymotion,google.   I am not satisfied with previous below question answer  How to save animation as a video format [duplicate] ()  Can someone guide me to a video lecture on this or someone please help in rectifying my current situation


How to upgrade from Ubuntu 20.10 to 21.04 beta?

I see this  message and I would like to test this version on my sandbox Linux Desktop (I have another Laptop for work tasks). I see this old AskUbuntu question  but as I mentionned  « Software & Updates dialog box doesn't contain "Pre-released updates" option any more » Question: what is the mainstream process to upgrade Ubuntu from 20.10 to 21.04 beta?


how to download and install hobby package for this latex scheme

I get  this following scheme but it doesn't work in my laptop, i work using texmaker and miKteX 2.9, i always get the error I can't find tikzlibraryhobby.code.tex, i enter the package manager to install it but its not found, can anyone help me to download then install it?  \documentclass[tikz]{standalone} \usetikzlibrary{hobby,patterns}  \begin{document}  \begin{tikzpicture} \draw[thick,->] (52,0) -- (60,0) node[anchor=north west] {$x'$}; \draw[thick,->] (56,-04) -- (56,04) node[anchor=south east] {$x_N$}; \node[draw=red,dashed,thick,circle,minimum width=4cm] (n) at (56,0) {}; \fill[pattern=north east lines,opacity=.6] (58,0)arc(0:180:2cm) -- (58,0); \draw[thick,->] (57.5,1.55) -- (58,2) node[anchor=north west] {$I^{+}(1)$}; \draw[thick,->] (57.5,-1.55) -- (58,-2) node[anchor=north west] {$I(1)$}; \draw (56,0) node[below right] {$O$} node{$\bullet$}; \draw (58,0) node[below right] {$1$} node{}; \draw (54,0) node[below left] {$-1$} node{}; \node[draw,circle,minimum width=2cm] (n1) at (50,3) {};  \begin{scope} \clip[draw](48,1) to[closed,curve through={(50,3) .. (52,4) .. (51,6) ..(47,6) .. (46.6,5) .. (45,3.8) }] (48,1); \node[draw,circle,fill=magenta,minimum width=2cm] (n1) at (50,3) {}; \end{scope}  \node[inner sep=1pt,fill,circle,label={below right: $x_0$}] at (50,3){}; \draw[->,shorten <= -4mm] (n1.90) -- +(0.7,0.7) node[pos=1.3]{$\Omega_1 \cap \Omega$}; \draw[->] (51,6) -- +(0.7,0.3) node[pos=1.3]{$\Omega$}; \draw[->] (n1.300) -- +(0.7,-0.3) node[pos=1.3]{$\Omega_1$}; \draw[->] (n1.10) to[bend left] node[midway,below]{8*} (n.120);   %% 8* = ??? \node at (50,-1){ Some text???}; \end{tikzpicture}  \end{document}


I'm used to work with Java where large amounts of examples are available. For various reasons I had to switch to C# and trying to do the following in SharpDevelop:  // Form has a menu containing a combobox added via SharpDevelop's GUI  // --- Variables languages = new string[2]; languages[0] = "English"; languages[1] = "German"; DataSet myDataSet = new DataSet();  // --- Preparation DataTable lTable = new DataTable("Lang"); DataColumn lName = new DataColumn("Language", typeof(string)); lTable.Columns.Add( lName ); for( int i=0; i<languages.Length; i++ ) {     DataRow lLang = lTable.NewRow();     lLang["Language"] = languages[i];     lTable.Rows.Add(lLang); } myDataSet.Tables.Add(lTable);  // --- Handling the combobox mnuActionLanguage.ComboBox.DataSource = myDataSet.Tables["Lang"].DefaultView; mnuActionLanguage.ComboBox.DisplayMember = "Language";   One would assume to see some values in the dropdown, but it's empty. Please tell me what I'm doing wrong ;(  EDIT: mnuActionLanguage.ComboBox.DataBind() is what I also found on the net, but it doesn't work in my case.  SOLUTION  mnuActionLanguage.ComboBox.BindingContext = this.BindingContext;   at the end solved the problem!


I recently got a new MacBook Pro and it only has 120 GB on it. On the system information page, I saw that garage band takes a whooping 46 GB on my Mac! I don't know how this has happened!  When I received this computer, I installed logic pro, and downloaded a ton of loops. Afterwards, I wanted to delete them for other stuff, so I deleted garageband and logic off my computer, and removed all files and audio loops from application support and elsewhere, however, it still shows that it takes 46 GB. How do I fix this?


I am trying to set up a Minecraft rig mouth that will have more controls and will be rounded, but I am having issues trying to figure out what this guy did here. First, he did what looked like a loop cut and slide, but instead of drawing a line it selected all the edges it passed through. He then cut to a new clip where the mouth was already set up like this.    The video is in 3 times speed but if you download a youtube plugin you can slow it down to 0.25 speed of the video and then if you do the spacebar trick you can slow it down so it shows 1 frame at a time and it is really slow.  if you want or need to see the video.  All I am asking is how can I create those 8 basic segments.


What is the probability of rolling $n$ dice until each side appears at least once?

We roll a die until each side appears at least once, then we stop.     What is the probability of rolling exactly $n$ dice?   I guess the answer is  $$6-6\left(\dfrac{5}{6}\right)^n\;,$$  but this may be wrong.  In trying to solve this problem, I read , but I couldn't solve the problem.


I pick a random subset $S$ of $\{1,\ldots,N\}$, and you have to guess what it is. After each guess $G$, I tell you the number of elements in $G \cap S$. How many guesses do you need?


Here is the sentence I'm having a trouble with:     ... a world that seems too big a place for any individual to contribute something unique.   Why does it say "too big a" and not "a too big"?  I apologize if something like this has been asked before but I didn't even know how to search for this.


getting titlesec package to respect title font, etc in style file

I am using a .sty file submitted by a journal which puts the section headers in capitals format. However, when i use the following  \usepackage[compact]{titlesec} \titlespacing{\section}{0pt}{*1}{*1} \titlespacing{\subsection}{0pt}{*1}{*1} \titlespacing{\subsubsection}{0pt}{*1}{*1} \titlespacing{\paragraph}{0pt}{*1}{*1} \titlespacing{\subparagraph}{0pt}{*1}{*1}   this formatting is replaced by a format of first letter in capitals, the rest in small lettering. Is there a way to get \titlesec to respect the fonts, lettering, etc of the style file?  Sorry if this question is not very clear.  I am happy to clarify further.


Why did Mad-eye Moody (disguised Barty Crouch, Jr) wait until the very end?

If Mad-eye Moody's only purpose was to get Harry to Lord Voldemort then why did he have to wait until the very end of the Tri-wizard tournament? Being a teacher he had Harry at his mercy anytime so should he take the pain of getting Harry into the tournament, risk helping him with the tasks, and so on? He could have easily done it any time during the entire year with any other object as the port key.  Why was the Triwizard cup chosen?  Is there anything that I'm missing?


How show that not exist two subgroups $H,K \leqslant S_{4} $ such that $H \times K\approx \operatorname{Dih}_4 $

I know that $S_4$ have 6 abelian subgroups of order 4 and 12 abelian subgroups of order 2, if i choose a subgroup $H$ of order 4 in $S_4$ and a subgroup $K$ of order 2 in $S_4$, when i do the direct product $H \times K$,this will be abelian (theorem). Then not exist two subgroups such that the direct product be isomorph to $\operatorname{Dih}_4$.  But, i've needed see the subgroups of $S_4$ for show that. Exist another way to show the same thing?.  I appreciate your help. thanks.


What is actually "relatively consistent"?

Gödel's incompleteness theorem states that: "if a system is consistent, it is not complete." And it's well known that there are unprovable statements in ZF, e.g. GCH, AC, etc.  However, why does this mean that ZF is consistent? What does "relatively consistent" actually mean?


echo "hi,my,name,is" | sed 's/,/\n/g' >out.txt   yields:  hi my name is   But in reverse:  sed 's/\n/,/g' out.txt   yields:  hi my name is   Why doesn't sed revert the operation with an inversion of the replace operation?


Booting Problem - Ubuntu GNOME 18.04 LTS

After installing AMD Driver for the HD 8670M graphics card I restarted the os and now it freezes on "Started User Manager for UID 121."  It seems that, this problem have happened in other versions of the OS especially with Nvidia graphics card, but my machine has an AMD. Does someone could help me please? How should proceed?  I don't have lots of experience with those kind of problems. By the way, Alt+F2 it's not working...


Given that mirrored Storage Spaces provide automatic corruption detection and repair, is space efficiency the only compelling advantage of parity over a mirror?   I am thinking that the poor write performance of parity justifies the relatively cheap cost of storage overhead incurred in a mirror.


I'm currently reading this document by the University of Texas in Austin about Predicate Logic, and got stuck on the following:   Note about nested quantifiers: For predicate P (x, y): ∀x∀yP (x, y) has the same meaning as ∀y∀xP (x, y). ∃x∃yP (x, y) has the same meaning as ∃y∃xP (x, y).  We can not interchange the position of ∀ and ∃ like this!  Example: U = set of married people. True or false? 1. ∀x∃y[x is married to y] 2. ∃y∀x[x is married to y]  I'm doubtful about the answer to this example. Also, some explanation about ordering of ∃ and ∀ operators would be appreciated.


How are these plastic rings used on my Shimano disk brake mount adapter?

I boughtt a Shimano SM-MA-R160 Disc Brake Mount Adaptor for my bike.  It came with these black plastic things in the lower right corner of the photo below. I have a bunch and don't know what are they used for:     What are those plastic thingies called? What are they used for? How are they applied? How important are they?


When running the --help switch, I got this.      andy7_~$ /usr/lib/libreoffice/program/swriter     javaldx: Could not find a Java Runtime Environment!     Please ensure that a JVM and the package libreoffice-java-common     is installed.   I did a search for jvm and java but Package manager has many picks with java in the name. What do I need?


UMVUE of $e^{-\lambda}$ from poisson distribution

Let $X_1,\ldots,X_n \sim$ Poisson$(\lambda)$. I wish to find UMVUE of $e^{-\lambda}$. Here $\overline{X}_n$ is complete and sufficient for $\lambda$ (hence for $e^{-\lambda}$??). Define $Y_i=1$ if $X_i=0,$ $Y_i=0$ otherwise. Clearly (I checked!) each $Y_i$ and hence $\overline{Y}_n$ is unbiased for $e^{-\lambda}$. Then I should be able to use the Lehmann Scheffe theorem to deduce the UMVUE. The estimator I get looks like $$\frac{1}{n} E\left\{\#X_i:X_i=0 \mid \sum_{i=1}^n X_i\right\}$$ whereas the correct answer is $$\left(\frac{n-1}{n}\right)^{\sum_{i=1}^n X_i}$$ I'd appreciate if anyone lets me know where I'm going wrong and guides me into the right path. Thank you.


Prove that for an arbitrary (possibly infinite) language, that for a finite L-structure $M$, if $M \equiv N$ then $ M \cong N$   I'm struggling to think of what to do, I presume the best thing is to keep it simple and assume the Language to only be relational.  I'd start by assuming we have a finite Language and taking $|M|$ = k = $|N|$ and as I've assumed the language to only be relational and finite take {$R_1,...,R_p$} to be the relation symbols. I'm guessing I need to show that there is some sentence $\sigma$ that is true in both $M$ and $N$? I have no idea what that sentence would be could someone help me out? Thanks.   Also how would I even begin to answer it in the infinite case?


I would like to install gcc compiler by this command apt install build-essential  and after pressing Yes, it asks me to insert some media.  Media change: please insert the disc labeled  'Ubuntu 18.04.4 LTS _Bionic Beaver_ - Release amd64 (20200203.1)' in the drive '/media/cdrom/' and press [Enter]  and this prompt repeats again and again  What's wrong?


How can I ask better questions despite being a noob to everything programming?

I've been noticing all through my SO "career" that my questions aren't always well received. They are either too vague or general or I seriously confuse terminology because well, frankly I don't know what I'm talking about. Being "self trained" or "internet trained" I find my education of anything programming to be very incomplete. Namely my terminology gets snarled up. It makes researching difficult which in turn leads to posting bad or vague and confusing questions. Probably a good example is in this post I made yesterday and edited today  where I gained a little more experience and was able to research for slightly better keywords and get what appears to be the exact answer to my question but better  So being new to everything programming, how can I learn to ask better questions?


I need to delete a "~" folder in my home directory.  I realize now that rm -R ~ is a bad choice.  Can I safely use rm -R "~"?


proof of $\sum_{n=1}^\infty n \cdot x^n= \frac{x}{(x-1)^2}$

I know that the Series $\sum_{n=1}^\infty n \cdot x^n $ converges to $\frac{x}{(x-1)^2}$ but I'm not sure how to show it. I'm pretty sure that has been asked before, but I wasn't able to find anything...


Creating js function for object that doesn't yet exist

I am creating a "to do list" javascript practice app. I have an input, and a "submit button". the submit button uses the text in the input.value. The submit button has an onclick that creates a new div with a nested h3 with the text from the input.value. The submit button also creates an "x button" and a "complete button" How can I create an onclick function for the "x button" which doesn't exist in the DOM until after I use the submit button? I want the "x button" to delete the entire div that was created with the submit button that includes the aforementioned x button itself, as well as the h3 and complete button that were created with the submit button.


MySQL - Exceeding VARCHAR length from SELECT statement

SELECT GROUP_CONCAT(DISTINCT(fullname) SEPARATOR ';')AS "FULLNAMES"   FROM Users;   I want to retrieve the fullnames of Users in a single row. However, the statement gives an incomplete result returning only the first 254 characters.  Is it possible to surpass this limitation?  Some might suggest to use the statement below instead and iterate through the result in my application but there's something that I would like to know.  SELECT DISTINCT fullname   FROM Users;


What is the available SQL Server Express database size?

SQL Server Express allows the maximum of 10GB/10240MB for a database size. I have a database which currently is ~8000 MB in size. The unallocated space is ~7000 MB. The question is: how many megabytes are available for growth/storing data on this database from that moment on? Is it ~2000MB or ~9000MB? What will happen if the database .mdf file reaches the maximum of 10240MB while the unallocated space is still around 7-8 000 MB? Will it prevent new records in the database from that moment on, or it will start using the unallocated space? Thanks!


One of those classic programming interview questions...  You are given two marbles, and told that they will break when dropped from some certain height (and presumably suffer no damage if dropped from below that height). You’re then taken to a 100 story building (presumably higher than the certain height), and asked to find the highest floor your can drop a marble from without breaking it as efficiently as possible.  Extra info   You must find the correct floor (not a possible range) The marbles are both guaranteed to break at the same floor Assume it takes zero time for you to change floors - only the number of marble drops counts Assume the correct floor is randomly distributed in the building


Allocating a temporary variable or compute the expression twice

I am trying to write a code as efficient as possible and I encountered the following situation:    int foo(int a, int b, int c)  {     return (a + b) % c;  }   All good! But what if I want to check if the result of the expression to be different of a constant lets say myConst. Lets say I can afford a temporary variable.   What method is the fastest of the following:  int foo(int a, int b, int c)  {     return (((a + b) % c) != myConst) ? (a + b) % c : myException;  }    or  int foo(int a, int b, int c)  {     int tmp = (a + b) % c     return (tmp != myConst) ? tmp : myException;  }   I can't decide. Where is the 'line' where recalculation is more expensive than allocating and deallocating a temporary variable or the other way around.


Java API to turn on debugging in a running JVM

Is there a programmatic way to turn on debugging in a running JVM instance? I am looking for an API that would make a running JVM, a debug server. The API would do the equivalent of   -Xdebug -Xrunjdwp:transport=dt_socket,address=<host:port>,server=y,suspend=n.


pgfplots - barplot with multiple bars on same coordinate, but labelled differently

I'm showing several data sets next to each other using multiple \addplot commands within a pgfplots axis environment. These are then further grouped into categories. The output of the graph per se is fine, however, I need each bar to be labelled separately - basically, I want the legend to be displayed directly underneath its corresponding element. I presume a picture will illustrate my problem more clearly:     I prepared an MWE:  \documentclass{minimal} \usepackage{pgfplots}  \begin{document}  \pgfplotstableread{ 0 35569 8842    134984   1 30428 4689    34077 2 32920 6207    73787    3 16462 7562    23496    4 12315 8572    16565    5 76572 19572   26030    }\dataset \begin{tikzpicture} \begin{axis}[ybar,         width=.9\textwidth,         ymin=0,         ymax=150000,                 ylabel={Y-Label},         xtick=data,         xticklabels = {             Category 1,             Category 2,             Category 3,             Category 4,             Category 5,             Category 6         },         major x tick style = {opacity=0},         minor x tick num = 1,         minor tick length=2ex,         ] \addplot[draw=black,fill=black!20] table[x index=0,y index=1] \dataset; %Data1 \addplot[draw=black,fill=black!40] table[x index=0,y index=2] \dataset; %Data2 \addplot[draw=black,fill=black!60] table[x index=0,y index=3] \dataset; %Data3 \legend{Data1,Data2,Data3} \end{axis}  \end{tikzpicture}  \end{document}


C++ what is the difference between class pointer to a new class vs pointer to a class object?

What is the difference between these two class initializers?   myClass myObject; myClass *myPointer1; myPointer1 = &myObject;  and  myClass *myPointer2 = new myClass;  If the first pointer is just a pointer to a class object, where does the second pointer point to?


Book recommendation for proving theorems

I love proving different things on mathematics, I mean, I love knowing where math theorems, methods and formulas come from. But most math books don't prove or show that kind of things. Do you know any book that could satisfy my wish? Obviously, there are lots of branches of mathematics, but I'm asking you to tell me, for example, "Oh, I know that X book proves all calculus theorems", "I've got a book called X that explains where all geometry formulas come from", etc.   Thank you


If $a^2+b^2+c^2=1$ then find the range of $ab+bc+ca$.   My attempt: We know  $$ 0\le(a + b+c)^2 $$ $$ 0\le a^2+b^2+c^2+2(ab+bc+ca) $$ $$ 0\le1 + 2(ab+bc+ca) $$ $$ -1/2\le ab+bc+ca $$ $$ range = [-1/2 ,\infty) $$ But the answer is $[-1/2 , 1]$. I would like to know how to proceed further.


How do I get a table like this in LaTeX?

I want to create a table just like this. How do I go about it? Do I use tables? A combination of tables and tikz maybe?


How can I stop Linux from changing Windows's clock?

I have a computer (HP-e010nr) that dual-boots Linux Mint 18.3 (Cinnamon, 64-bit) and Windows 8.1 (64-bit). Both are installed via BIOS compatibility mode (the Windows installer refused to use UEFI). My issue is:  When I start Linux, it sees that the system clock is not UTC, so it changes it to UTC (and then displays it 7 hours back to keep the right time). When I start Windows, it expects the system clock to be normal time (not UTC). It displays the clock as 7 hours ahead of my time zone, making timestamps wrong.  I can change the hardware clock to normal time after shutting down Linux, but this is very annoying to do. I would like them to both display the same time if I shut down Linux and booted Windows.  Is it possible to stop Linux from changing the hardware clock so that other operating systems (Windows and Android) will display the correct time?


If router is off for a few days, do you have an ip address as far as ISP is concerned?

I have an ISP which assigns IP addresses dynamically. If I go out and turn my router off I am always assigned a new one once I turn it back on. Does that mean that...  1) my previous IP goes elsewhere when my router is turned off?  2) i dont actually have an IP address if my router is off for a day or more?


Is there any program for Linux that has about the same functionality and usability as Microsoft OneNote? At the moment I am checking out Basket (for KDE), that seems to point to the right direction, but still lacks much of the functionality of OneNote and is very buggy unfortunately.  For those of you that don't know what OneNote is, here is the first paragraph from the :     Microsoft OneNote (formerly called   Microsoft Office OneNote) is a   computer program for free-form   information gathering and multi-user   collaboration. It can gather user's   notes (handwritten or typed),   drawings, and audio commentaries and   share them with other users of   Microsoft OneNote over the Internet.   The desktop version of OneNote is   available for the Microsoft Windows   platform.


Does measurement, quantum in particular, always increase the total entropy?

Measurement of a quantum observable (in an appropriate, old-fashioned sense) necessarily involves coupling to a system with a macroscopically large number of degrees of freedom. Entanglement with this "apparatus" takes care of the decoherence. It is often said (I can provide references upon request) that the remaining problem is the one of "selection", and this is the point where one invariably invokes something philosophically radical, like many-worlds interpretation.  In the above (pretty standard) context, I am trying to make sense of the following observation. Looking at the measuring system from a statistical mechanics point of view, it seems that triggering a particular macroscopic outcome requires spontaneous symmetry breaking via a (thermodynamically) irreversible transition of the "apparatus" from a metastable to a higher entropy final state. My attitude is that "statistical mechanics point of view" is not far from "decoherent large quantum system".  So, the question is:  Is it fair to say that statistical irreversibility ("the second law") and quantum measurement irreversibility (the "wave-function collapse") are necessarily linked? Can this link be made more concrete (e.g., traced in details in a particular model)? Can you give references to approaches to the measurement problem that explore this connection?


Hibernate - dealing with float values along with MS SQL Server

I am trying to save a float value using hibernate into MS SQL Server. the value is 2.4 and when it get saved to the database, it becomes like this.  2.40000009536743  Here is the column definition in my entity class for this field.  @Column(name = "fTotalChipWeight")     private float totalChipWeight;   Could anybody advise me why this is happening this way  This is how the database column is defined


Removing my proposed tag left dead ends in my profile pages. How can I tell what happened?

I am a bit confused about what happened to a  tag I proposed yesterday. Please, do not judge on the usefulness of the tag (off-topic. could possibly be another meta question)  In my profile page, when I go to my yesterdays  there is a  position, but it leads to Page is not Found which makes it hard for me to identify what it actually is. (I think it's the proposal of the tag)  Today, when I look at the  of my profile I see an   :   Unfortunately, it is not perfectly clear to me what an orphan wiki means based on  answer. I would appreciate if someone reworded that for me.  There are no results returned when I am searching for  tag on the  page  There is my  under my activity tab in my profile which seems to be approved, however it seems like an unfinished sentence   on what?  What happened to  tag? Did it get declined/removed?


I want to turn a rectangle with ports in the top and bottom into a shape I can use with a node. How can I do this?    \documentclass[tikz,14pt,border=10pt]{standalone} %%%< \usepackage{verbatim} %%%> \begin{comment} :Title: abc :Tags: def :Author: ghi :Slug: jkl \end{comment} \title{test_portbox} \usepackage{textcomp} \usetikzlibrary{shapes,arrows} \begin{document} \begin{tikzpicture}[auto, line width = 0.5, node distance=2cm, >=triangle 45]  \draw (0.2,0) -- (0,0) -- (0,1) -- (0.2,1); \draw (0.4,1) -- (1,1) -- (1,0) -- (0.4,0);  \draw [line width=0.1] (0.2,0) circle (0.025) -- (0.4,0) circle (0.025); \draw [line width=0.1] (0.2,1) circle (0.025) -- (0.4,1) circle (0.025);  \end{tikzpicture} \end{document}


$X$ and $X\times X$ has the same cardinal, if $X$ is inifinite.  How to show it?  give a suggestion. Do we have some easier method?


I was browsing the meta footer and I saw a strange white space underneath the footer.    Should it be there, and if yes, why?  EDIT: As you can see this happens on Chrome. I also tested in IE and Firefox and it has the same effect.


How to send text to a command and THEN read from terminal

I'd like to know if it's possible to send some to a command's stdin and then keep reading from the terminal.  The problem i'm trying to solve is executing some initialization code every time i open a Node.js REPL, so i have some functions available at the REPL from the start. Basically, to automate this:  $ node > require('./myutils') > ... continue using the REPL   I now i can use here string to send some text to the command's stdin:  $ node <<<"require('./myutils')"   That will execute my initialization code, but will also close the REPL immediately after that.  Maybe there's another solution for this particular problem with Node.js, but i'd look to know if there's a general way of mixing input from a string or file and then keep reading from the terminal.  Update:  work, but the Node.js REPL won't run in the interactive mode by default (this is expected, as we're not reading from a terminal). Luckily, there's an -i option to force the interactive mode in the Node.js terminal:  { echo "require('./myutils')" ; cat ; } | node -i


How to use a texture in real world scale?

How to apply texture on an object in real world scale? I mean can I control the texture scale mathematically like in 3DS Max? If I have the pattern which is 1000 by 1000 mm, I need to apply it on a model with this exact size to represent the product I design as defined as possible.


Why input type=file not working with $.ajax?

I have a <s:file> tag inside the form which generates a HTML <input type="file">. When I submit the form via form submission (e.g. submit button, etc.) everything works fine in the action method. However, when I change my code to:  $.ajax({     url: "actionClass!actionMethodA.action",     type: "POST",     error: function(XMLHttpRequest, textStatus, errorThrown) {                 alert('Error ' + textStatus);                 alert(errorThrown);                 alert(XMLHttpRequest.responseText);             },     data: $(form).serialize(),     success: function(data) {                 ...             } });   In the backend, the file field is always null.  The file field is defined in  the action class as follow (with setter and getter):  private File impFileUrl;   Is it because now the form is serialized so that the file field can no longer be set properly in the backend?


So I had a problem, sound was going through speakers and headphones - BOTH. Found a guide in this answer:   That I should put this code:  alias snd-card-0 snd-hda-intel options snd-hda-intel model=dell-m4-1 enable_msi=1   To the /etc/modprobe.d/alsa-base.conf file. I did it, and now NO SOUND AT ALL.  Both headphones and line in - does nothing  Sound settings tab shows up - Dummy output.    Any ideas?


How am I supposed to kill the frost troll?

So I've run into two frost trolls so far.  The first one I took advantage of bad pathing which I feel bad about because it ruined the game immersion.  The second one I used a full unrelenting shout and got a bunch of free shots in while it was unconscious, but then had to back off since it really didn't go down more than 1/4 of its life.  I finally took advantage of bad pathing to run past it to the end of the dungeon.  This feels really odd because I have taken down a handful of dragons, including once being attacked by two at the same time.  Is there any good strategy to kill a frost troll which won't make me feel like I'm glitching the game?


I use codeblock for compilation.  code:  int main(){ int l=pow(10,2); cout<<l; return 0; }   OUTPUT-99  int main(){ int l=pow(10,3); cout<<l; return 0; }   OUTPUT-1000


Evaluate $\int_0^{\infty} x^2\,e^{-x^2}\,dx$ if it is convergent.

evaluate $$\int_0^{\infty} x^2\,e^{-x^2}\,dx$$ if it is convergent. I cannot figure this out for the life of me. Please help!! thank you


How can I get my temporary quest follower to stop following me in Skyrim?

Me and my brony, Aela the huntress, went out and attempted to clear a certain cave near Whiterun, destroying the Silver Hand clan to restore honor to our werewolf kind. I was not prepared for the strength of the final adversary, Kelv the Skinner. After many failed attempts to end him, Aela and I fled the cave. Now, I cannot convince her that the quest is to be temporarily postponed, and she follows me, no matter where I go. Can someone suggest a way to remove her from my party? I have already deselected the quest.  This is the PS3 version of Skyrim. Ergo, I cannot go into the system console or whatever and change anything about the game.


Hide text from the navigation bar in the first frame

I hope you're doing great. When I using beamer, how can I set the first frame, with the respective navigation bar but without text (only with the rectangle located above).  Best regards


Keyboard shortcut to get focus webpage after selecting address bar

The keyboard shortcut to select address bar (in chrome) is Ctrl + L, ALT D, or F6. But what is the keyboard shortcut to un-select the url and get back to the webpage? If I hit tab, the focus cycles within suggested urls.


Is there a word in English meaning "see something incorrectly"?

For example, I saw someone just now. I thought he was Jack, but turned out he was not. Or, I saw something and recognized it as something else incorrectly.  Is there a word for such situations?  I know if I read something wrongly, I could say "I misread it".  and if I hear something wrongly, I could say "I misheard it".  But I cannot find the word "missee" in any dictionaries.  Is there something else people use?


What is the weather like in south of Tenerife in early December?

I'm looking for a sunny escape from cold European winter. Therefore I was thinking about the canarian islands, more specifically Tenerife. As there are direct flies from my nearest airport.  Because I didn't make it to the beach this year, I would like to be able to do that. And there comes my question. I found very different information on what the weather and temperatures will be like. Most say it will still be "bikini weather" during the day. But I also read that the sea will be rather cold (below 20). So at least for me not very inviting for a long swim in the sea.  So can anyone help me with personal experience? What will the situation be like in lat's say Costa Adeje or nearby area?  Edit Thanks for the links to historic weather data. I already checked those. I'm really more looking for personal experience as mentioned. Numbers alone can be misleading or not cover all microclimas. And I heard there can be big differences on Tenerife


Restrict node list in entity reference field based on node field

My "Article" nodes have a "domain" field that links to a taxonomy term. My "Article" nodes also have a repeatable "entity reference" field "more like this" that links to other "article" nodes.  How can i restrict the list in the "more like this" field to show only the nodes that have the same "taxonomy term" that the node i am currently editing ?  Thanks a lot !


Can I counterspell a Subtle spell without material components?

Counterspell   1 reaction, which you take when you see a creature within 60 feet of you casting a spell.   Can I Counterspell a creature that completely eliminates component requirement?     Subtle Spell   When you cast a spell, you can spend 1 sorcery point to cast it without any somatic or verbal components.   If the spell is subtle then can I see it’s being cast in order to counterspell it?


Why does my own dupe CV on my own question not immediately close it?

If I vote to close my own Q as dupe, it has no effect other than casting a dupe vote.   But if I then refresh the page, I see that note on top of it asking whether that other question solved my problem.   Clicking on "Yes" there finally lets the Community user close it.  An example where this happened on Ask Ubuntu is .  Why doesn't my first own dupe close vote immediately close my own question instead?


What am I missing? Flexbox doesn't center the container in this snippet here

I'm trying to center the container and I don't know why it doesnt work. html, body {   height: 100% }  .container {   min-height: 20em;   width: fit-content;   background-color: #ffffff;   display: flex;   flex-direction: row;   align-items: center;   justify-content: center; }


Choose: Six years (seems, seem) too much time to build a house.   I have this question while solving an exam in English, it appears to be "seems" but the plural noun phrase (six years) leading you to "seem".


They say that about 80% of the matter in the universe is  -- some unknown substance that has mass. But what is this matter expected or speculated to be composed of? For example might it exist as neutrinos or protons or atoms of hydrogen or something like it? Or might whole worlds exist out there made solely of dark matter -- worlds that might actually sustain life?


C# open cmd as admin via code and change font and background colors

Trying to change the cmd window colors. this does not work?               ProcessStartInfo p1 = new ProcessStartInfo();              p1.Verb = "runas";              p1.FileName = "cmd.exe";              p1.Arguments = "color 80";              Process.Start(p1);


My CPU and Dual GPU and Utilization monitoring tool

First of all I haven't enabled the overclocking anywhere yet, how can my cpu work at its Overclock frequency?(4.4 Ghz as you can see on the screenshot bellow!) and if that is the case why it's called overclocking since I can't manage the throttle, that's not gonna age the cpu faster since this is not its base frequency, and my cpu is literally clocking 4.4 right now??, just like a cpu with the base frequency of 4.4?  Second, I just started up the windows 10(Fresh Factory-Reset, Bare metal) with one PotPlayer and Micrsoft Word, with no game running, why 7.3 GB of my memory is already occupied.  Third, I have one Intel GPU and one NVIDIA Quadro T2000, Windows can use them at the same time? So if I run a GPU intense program, it will be multi threaded through the both GPU's pipelines?


Do i need visa to europe with usa reffugge travel doc

Do i need visa to travel to the united kingdom with USA refugee travel documents ?


Is it OK to crosspost Stack Overflow questions, now that the Portuguese SO is open?

Somehow related (but not exactly) to   Let's suppose I have a question in the following manner:     How do to x with y   Now, let's say a user is proficient with more than one language, in the current case, English and Portuguese (as of the time of writing, they are the public SO). Would it be wrong to crosspost on both SO and wait for anyone to answer?  Note that this is different than the linked question in the following way: we aren't purposely flooding a new SO with already asked questions by translation. Rather, we're allowing for good-written answers to appear, in different languages, at a natural pace.


Error while trying to install wine-stable 5.0.0

I'm new in the community. I have a problem while installing wine, it says:   "The following packages have unmet dependencies:  winehq-stable : Depends: wine-stable (= 5.0.0~bionic) E: Unable to correct problems, you have held broken packages."    I tried with aptitude to install all other packages that may be broken, but I don't know what to do now. My Gnome version is 3.28.2, I use Ubuntu 18.04 (Bionic) . If need more details are needed please let me know.


Appending a variable to different lines of a file in bash

So say I've got a file with the following text in it.  And the source file I'm reading is like this:  #0  abc 2016-08-06 01:12:57 AM  9.1%    779.9M of 1G    156.3M of 1G #1  abc 2016-08-06 02:33:47 AM  12.1%   339.9M of 1G    126.3M of 1G   The following is the script I'm using  #!/bin/bash  opFile="opfile.txt" sourceFile="TestOutput"      if [[ ! -e "$opFile" ]]     then     {         touch $opFile         count=0         grep "#" "$sourceFile" | while read -r line ; do         {             cpu=$(grep "#$count" "$sourceFile" | cut -f 4 | cut -d% -f1)             mem=$(grep "#$count" "$sourceFile" | cut -f 5 | cut -dM -f1)             disk=$(grep "#$count" "$sourceFile" | cut -f 6 | cut -dM -f1)             echo -e "$cpu\n$mem\n$disk" >> "$opFile"             ((count++))         }            done      }     else     {         count=0         lineCounter=0         grep "#" "$sourceFile" | while read -r line ; do         {             cpu=$(grep "#$count" "$sourceFile" | cut -f 4 | cut -d% -f1)             mem=$(grep "#$count" "$sourceFile" | cut -f 5 | cut -dM -f1)             disk=$(grep "#$count" "$sourceFile" | cut -f 6 | cut -dM -f1)             ((lineCounter++))             sed ""$lineCounter"s/$/,"$cpu"/" "$opFile" | tee "$opFile"             ((lineCounter++))             sed ""$lineCounter"s/$/,"$mem"/" "$opFile" | tee "$opFile"              ((lineCounter++))             sed ""$lineCounter"s/$/,"$disk"/" "$opFile" | tee "$opFile"              ((count++))          }         done     }     fi   Now, the script needs to be run multiple times on that $sourceFile since the numbers in that file would keep changing. So the first time the script runs, the output is so  9.1 779.9 156.3 12.1 339.9 126.3   And the second time it runs (assuming the values are the same in the source file), the output should look like.  9.1,9.1 779.9,779.9 156.3,156.3 12.1,12.1 339.9,339.9 126.3,126.3   Now, the sed line I've used is correct, I'm pretty sure, but I'm having issues when it comes to putting that in the file. I could've used the >> output redirecter but that's printing everything on a new line. Tee is working slightly unexpectedly, sometimes it'd doing the right thing, other times, my opfile.txt is empty. Any idea on how to put my sed output in the file correctly? And no, preferably, I wouldn't want anything displayed on the stdout.  Thanks!


Number of pairs of integers $(a,b)$ with $a^2+b^2=n$ for a constant $n$

Is there a more general formula for the number of pairs of nonnegative integers $(a,b)$ with $a^2+b^2=n$ for arbitrary $n$?


Difference in time while printing sorted and unsorted array

I have created a sample class which contains two integer array; one sorted and other unsorted. And I am printing contents of the array. Time taken to print sorted array is twice the time time required to print unsorted array.  Refer the code:  public class Demo {  public static void main(String[] args) {      int[] array1 = {1,2,3,4,5,6,7,8,9,10};     int[] array2 = {10,3,4,2,6,7,8,1,5,9};      long start = System.nanoTime();      for(int a:array1){         System.out.println(a);     }      System.out.println("Time required by sorted array\t"+(System.nanoTime() - start) / 1000000000.0);      start = System.nanoTime();     for(int a:array2){         System.out.println(a);     }      System.out.println("Time required by unsorted array\t"+(System.nanoTime() - start) / 1000000000.0); }  }   Output:   1 2 3 4 5 6 7 8 9 10 Time required by sorted array   3.89505E-4 10 3 4 2 6 7 8 1 5 9 Time required by unsorted array 1.37727E-4   Why is there difference in time while displaying the numbers. Also I read somewhere that sorted array process faster, here the case is different.


Hulk has extraordinary powers, well above that of a normal human being.   Can we say that Hulk is a mutant?


How Wordpress understands what do with the (all) key in the $wp_filter array?

In the isset( $wp_filter['all]), the all key will fire for all other hooks. i need to know how Wordpress understands what to do if the key all is used.. It should be defined somewhere which make Wordpress understands it.


Showing that a particular harmonic function is constant

Let $u$ be a real-valued harmonic function in the complex plane such that $$ u(z) \leq b + a \log{|z|} $$ whenever $|z| \geq 1$(for some constants $a > 0$ and $b$). Show that $u$ is constant. I know that harmonic functions satisfy: $$\frac{\partial^2 u}{\partial x^2} + \frac{\partial^2 u}{\partial y^2} = 0 $$ But, how do I use this to show that $u$ is constant?


I've got an image floated left, and I want to vertically align some text to the image so that the text sits in the middle of the image.  Any ideas how it's done? I have tried many solutions provided on this site, but none are working for me.  As shown below,  does not work.    /* Limiting outter width to illustrate the problem */  .cart-helper-outer {   width: 200px; } /* Makes helper items full width */  .cart-helper-inner {   width: 100%;   float: left; } /* Displays image left of text */  .cart-helper-inner img {   max-width: 50px;   float: left;   margin-right: 2.5%;   vertical-align: middle; /* this does not work*/ } .cart-helper-inner p {   vertical-align: middle; /* this also doesn't work*/ }

Secure checkout with bank grade encryption

Secure checkout with bank grade encryption

Secure checkout with bank grade encryption


I have difficulty of understanding p-value from An Introduction to Statistical Learning by Gareth James • Daniela Witten • Trevor Hastie Robert Tibshirani (2015) : 67  Consider simple linear regression equation $$Y= β_0+ β_1 X$$  Null hypothesis states Y doesn't relate to X, Mathematically $β_1\approx0$ To reject Null hypothesis, we should prove $β_1 >> 0$ After performing linear regression I calculated coefficient to be $\hat{β_{1}}$ .But since number of samples are limited, There is no confidence to reject null hypothesis.   So I calculate t-statistic as $$t_{statistic}=\frac{\hat{β_{1}} - 0}{SE(\hat{β_{1}})}$$ It is trivial to understand that higher t-statistic implies more confidence in $β_{1}$ since $β_{1}$ is larger than error in calculation of itself, hence we can reject Null hypothesis for high t-statistic values    From:  $$t=\frac{\hat{β_{1}} - {β_1}}{SE(\hat{β_{1}})}=\frac{Error\,in\,calculated\,β_{1}}{(Estimated\,Variance)/(\sqrt{n})}$$    Note here that ${β_1}$ & ${SE(\hat{β_{1}})}$ are random variables and vary with batch of samples observed. Let's denote t-distribution as $T(t,n)$ and ${t\,statistic}$ as $T_{st}$   Probability of observing  ${t_{obs}}\ge{t\,statistic}$ is p-value $${p}{-}{value} = \int_{|t|>|T_{st}|}T(t,n)$$ What is mathematical derivation for ${p}{-}{value}\approx 0 \implies β_1 >> 0$ is large ?    I have a quantitative explanation that t-statistic follows t-distribution, if we assume $H_{0}$ is true, and ${p}{-}{value}$ i.e. $\int_{|t|>|T_{st}|}T(t,n)$ denotes probability of getting a value of "t" $\ge T_{st}$ which being less implies hypothesis is false


How do you implement a good profanity filter?

Many of us need to deal with user input, search queries, and situations where the input text can potentially contain profanity or undesirable language. Oftentimes this needs to be filtered out.  Where can one find a good list of swear words in various languages and dialects?   Are there APIs available to sources that contain good lists? Or maybe an API that simply says "yes this is clean" or "no this is dirty" with some parameters?  What are some good methods for catching folks trying to trick the system, like a$$, azz, or a55?  Bonus points if you offer solutions for PHP. :)  Edit: Response to answers that say simply avoid the programmatic issue:  I think there is a place for this kind of filter when, for instance, a user can use public image search to find pictures that get added to a sensitive community pool. If they can search for "penis", then they will likely get many pictures of, yep. If we don't want pictures of that, then preventing the word as a search term is a good gatekeeper, though admittedly not a foolproof method. Getting the list of words in the first place is the real question.  So I'm really referring to a way to figure out of a single token is dirty or not and then simply disallow it. I'd not bother preventing a sentiment like the totally hilarious "long necked giraffe" reference. Nothing you can do there. :)


Best way to spread load on monitor clamp

I saw this monitor clamp crush a hollow Ikea desk:  To prevent this, the load of the clamp should be spread. But spread how? Say I had a 1.5mm thick sheet of steel.  If I placed it here, would the same thing have happened, but this time the crack would have run along the long side of the steel sheet? Does the fact the width of the steel doesn't go past the front of the clamp make a difference?    If I moved it forward slightly, I predict it would have prevented damage to the desk. But why? Isn't the load spread amongst the same amount of surface area compared to the above image?    Would it make a difference if the steel sheet was placed like this? I think the steel sheet would have a sort of lever effect as the centre of gravity is closer to the area covered by the steel sheet load spreader    Does the tightness of the clamp affect anything? eg loose clamp, exaggerated for effect, the two red dots are where the force is concentrated:   tight clamp, the red lines are where the force is spread:  Or would there still be a concentration of force at the red dots as the monitor moves the centre of gravity and adds a torque effect? This question is not the same as  ; that question asks how, this question is more specific as it asks why.


Does Common Lisp have a something like java's Set Interface/implementing classes?

I need something like , a collection of elements which contains no duplicates of any element. Does Common Lisp, specifically SBCL, have any thing like this?


In The Walking Dead, what are the "rules" of zombie "camouflage"?

I'm a little confused by this whole blending in with zombies business.  This much I do know:   Michone and Andrea are able to camouflage themselves for an entire winter with Michones two walkers.   Rick is able to "hide" during his fight with Shane at the prisoner drop-off site by rolling a walker on top of him.  I believe Darryl does something similar at the congested highway to save himself and T-Dawg.     The questions:  Is the camouflage literally based on a sense of smell?  Some sort of post death sixth sense?  I can't name the specific episode, but in Season one Rick and Glenn cover themselves with zombie guts to escape, and when it starts to rain, washing off some of the guts, the surrounding zombies immediately begin to take notice.  Why?  If two chained zombies can mask two adults within about a five foot radius, shouldn't that mass of zombies have been more then enough to provide cover?  By the same reasoning, as soon as the first couple zombies got close to you, shouldn't the rest of the zombies lose interest?  Is "disarming" or killing a zombie the only way to make it functional as camouflage?


I just realized that /usr/bin/poweroff and /usr/bin/shutdown are symbolic link to systemctl, but I don't know how systemctl is being run.  so is there any difference between /usr/bin/poweroff and /usr/bin/shutdown?    EDIT: when I call any of these two programs, systemctl is being executed but I don't know what command/parameter is passed to systemctl.  when I type systemctl --helpthere are two options that may come into play     halt                Shut down and halt the system poweroff             Shut down and power-off the system   but something tells me that both poweroff and shutdown are the same in here (I'm guessing)  I'm running Archlinux


Why use this->ObjectName instead of this.ObjectName in c++

Hello World, I have been wondering why in c++ we use the this->ObjectName instead of this.ObjectName when referring to an object in c++. This is a simple syntax using the this->ObjectName :        int x = 34;      void take(int x) {       this->x = x;      }   But in other programming languages like java, we use :        int x = 34;      void take(int x) {       this.x = x;      }   So what am asking is why does the this statement in c++ differ from the this statement in java


Locked post sign on duplicate says still accepting answers

Over , it's a duplicate, so it's not accepting answers, but this locked sign:  disagrees.  Seems like a bug that it wouldn't recognize a closed post.  Can we fix that? If this needs different tags, or is not correct in any way, please let me know.


Probabilty of a certain run in a 1000 coin flips

So a run of $x$ heads has the probability $0.5^x$.  Thefore a run of $9$ would be $0.5^9 = 0.001953125$.  But what is the chance of that run of $9$ occuring in $1000$ coinflips? Can anyone please explain how to work this out?


How can I **EASILY** install this Mac OS X on a bunch of Macs without downloading the whole thing every time?

I am a Linux guy, and I have to provide support for about 15 Mac users. I need to install this OSX 10.8.x and I got the license codes all sent to me. But I can't figure out how to get whatever file on mine, so I can re-use it. How do I do that?  Do I really have to go through this whole registration info where I have to enter a credit card and everything else about me before I can get access to anything?


I want to "annotate" a pdf with arrows and stuff drawn in tikz, but I don't understand how to put tikz draw commands inside the overpic put command.  Code:  \documentclass{standalone} \usepackage{tikx} \usepackage[percent]{overpic}  \begin{document} \begin{overpic}{filename_of_orig_pdf}  \put(0,0){Can easily put text}  \put(x,y){ \draw[] {}; }     %?  \end{overpic} \end{document}


Should I vote to close a duplicate question, even though it's much newer, and has more up to date answers?

I have seen this many times, a question is being asked because a previous, duplicate question was asked and answered a few years ago and has no longer relevant answers.  The  is to edit the old question, or add new answers to it, but it is not always happening.  I was wondering, should I still mark it as duplicate and vote to close it? Or just leave it as is?


Though we can achieve the same result when we put right table in left and use left outer join. Then what is the significance of Right Outer Join?


Instance values being overwritten by latest incoming value

I have two classes Test_1 and Test_2 where test_2 includes the method setValues. class Test_1():      def __init__(self):         self.dim = float         self.list = Test_2()       def init(self, dim, valuesT, valuesW):         self.dim = dim         self.list = [Test_2()] * dim           for i in range(self.dim):             self.list[i].setValues(mean[i], valuesT[i], valuesW[i])   class Test_2():      def __init__(self):          self.mean = float         self.T = float         self.W = float              def setValues(self, mean, T, W):           self.mean = mean         self.T = abs(mean - T)          self.W = abs(W - mean)   When I create an instance of Test_1 and call the init method of this class passing the params (3,[1,2,3],[3,4,5], [6,7,8]) I am expecting the creation of 3 instances of Test_2 class and for the T and W values to be initialised in the list objects. However this is not the case and the T and W values seem to be overwritten for all 3 Test_2 objects to the latest T and W values. The below code produces the values: 1 3 6 6 6 6     for i in range(self.dim):         self.list[i].setValues(mean[i], T[i], W[i])         print("List while in loop: ", self.list[i].mean)      for i in range(self.dim):         print("List after loop: ", self.list[i].mean)  Could anyone help shed some light on why this may be? I'm fairly new to OOP.


Center motor ebike costs more, is it worth it?

I am 90% sure that I will buy an e-bike. Today one of my friends who owns an ebike strongly suggested that I should buy one with center motor, because they are more efficient and battery life will be longer.   Where I live ebikes with  costs three times more than ebikes I found .   Will it worth to buy a center motor ebike even it is more expensive?


An inequality involving limit inferior and limit superior

I have the following assertion to be proved for $a_n > 0, \forall n \in \mathbb{N}$:  $$ \underset{n \rightarrow \infty}{\mathrm{lim \inf}} \  \frac{a_{n+1}}{a_n} \leq \underset{n \rightarrow \infty}{\mathrm{lim \inf}}\ a_n^{1/n} $$  I am totally stumped as $a_n$ can have arbitrary behavior. Any hints please?


Appending sequential characters to StringBuilder

I am trying to append sequential characters: A, B, ... AA, AB, ... to the beginning a a stringbuilder type.  The problem I am having is that it will append all ASCII characters and not double characters.  My code looks like this:  string prefix = null; System.Text.StringBuilder text = new System.Text.StringBuilder(); for (j = 0; j < genList.Count; j++) {     prefix = "." + Convert.ToChart(j + 65).ToString();     text.Append(prefix + genList[j]); }


Duplicate Close message sends wrong message to users

Similar to .  I was helping a user (through comments) with a question, and I believe a question was closed as a dupe for a wrong reason. Then, I read the message:    So, we already established there was a question, possibly even a very similar question, but we want to encourage the user to ask a new question? This seems backwards, and a great way to earn users the ability to either learn to ask, or to mess up and ask ANOTHER question that may get closed.  I propose that it changes to say to edit the question to include more details. For example, maybe it's a problem with Product A on Platform B, but the duplicate is for Product A ver 2 on Platform C? I believe it could help users make constructive edits to their content on their own, and hopefully reopen the questions not as a duplicate, if done correctly.


Is it wrong to refer to results as "nearly" or "somewhat" significant?

The general consensus on a similar question,  is that "highly significant" is a valid, though non-specific, way to describe the strength of an association that has a p-value far below your pre-set significance threshold. However, what about describing p-values that are slightly above your threshold? I have seen some papers use terms like "somewhat significant", "nearly significant", "approaching significance", and so on. I find these terms to be a little wishy-washy, in some cases a borderline disingenuous way to pull a meaningful result out of a study with negative results. Are these terms acceptable to describe results that "just miss" your p-value cutoff?


Singular or plural in these sentences . .

I've often written sentences like these:   The structure and linearity here is [are?]what is [are?] stifling creativity. Compare: The pencil and pen are in the room. [Where is seems wrong] The project is based on chapter information and book category, which is [are?] useless when guiding you toward the actual objectives. There is [are?] a table and chair in the room. Compare: A table and chair are in the room   Is the is appropriate in these sentences? Especially the first one; I don't quite get the rules at play here, so am only going by what sounds right.


What is exactly the "legal right to work in this location"?

I mostly ask this because I'm from Spain and I wouldn't mind working on the United States.  I have the legal right to work there ... provided a did get a Green Pass for which usually helps a lot having a job offer in the first place so... Does it refer just to something like I'm of age and I'm not crazy nor do I intent to kill the USA president?   Or should I uncheck the "legal right" checkbox? And if I do, would that mean that I won't be appearing on US employers searches?


How to remove remembered autocomplete items in Firefox and Chrome?

I love the way the browser remember the text I entered into a form field - especially when I'm a developer. It saves lots of my typing time.  Though, sometimes there are unwanted remembered items and need to be removed. I don't know how to do that in Firefox and Chrome. Please help!


Is there a way to search for community wiki 'questions'?

I tried a search, but I get answers also in the results. I'd like to search only questions.  I tried: wiki:1 question:1 (shot in the dark) but it didn't work, I still get answers in the results.  In contrast, perhaps a way to search only answers would be useful too  So I propose the question and answer search operator to combine


Question  Is there a way to check whether a macro is fully expandable (or rather "safe in an expansion-only context" )?    Consider this code:  \def\a{Just a string} \def\b{\a} \def\c{\def\unsafe} \def\d{\c}   How could I check which of the macros (a-d) are safe in an expansion-only context? By looking at them I know that a and b are whereas c and d are not but if I wanted to know the same for a macro I haven't written myself this could get quite useful.      Background  I am working on a way to detect whether some input is a valid number in PGF. For this I developed  which makes use of passing the input into \pgfmathfloatparsenumber. The problem I have run into is that said macro appears to somehow manages to expand the input until there is an error (if the input is in fact not safe in an expansion-only-context). I tried using protected, noexpand and similar but somehow PGF manages to circumvent those.    So the idea is to check whether the input is safe before actually passing it to PGF. The problem is: I don't know how I'd go about that...


Is there any possibility to autohide the Panel in GNOME session?  In picture below I selected the area what I mean.


What is the reason behind why energy must always be conserved, apart from observation?

I know that we see in experiments (physical and thought) that energy is always transformed into something else, but what propels our universe to behave this way? What is happening at small levels that only allows conservation as a possible outcome and not destruction of energy?    Update: Based on a given answer stating that energy is mass, I should probably then expand this question into "Why must mass must always be conserved?"


What was the purpose of the test in the room with uncomfortable chairs in Men in Black?

In the beginning of Men in Black, when Will Smith is in the room with the other candidates for the job, they're all sitting those egg-style chairs with a table in the middle. This is where they're required to take the test.   Rip Torn leaves the room so they can all take the test and the next 3 minutes or so show all of them struggling to take the test in those stupid chairs. Until Will Smith finally gets up and drags the table over to himself, disrupting everyone else in the room.  Was this a test for them all along to see who would take initiative and get the table? To see who had the most common sense and could handle themselves best in stupid situations maybe?


Show that if $Y$ is a subspace of $X$, and $A$ is a subset of $Y$, then the topology $A$ inherits as a subspace of $Y$ is the same as the topology it inherits as a subspace of $X$.  First some notational specifications: Let us define $\tau$ as the topology of $X$ $\tau_{Y}=\{U \cap Y; U \in \tau \}$; $\tau_{A}^Y=\{V \cap A; V \in \tau_{Y} \}$ and $\tau_{A}^X=\{U \cap A; U \in \tau \}$  Let us show that $\tau_{A}^Y=\tau_{A}^X$  $\subset$: Let $V \cap A$ be an element of $\tau_{A}^Y$ such that $V \in \tau_{Y}$  Then, there exists $U\in \tau$ such that $V=U\cap Y$  $V\cap A=(U\cap Y)\cap A=U\cap (Y\cap A)= U\cap A$  Hence: $V\cap A \in \tau_{A}^X$ and so: $\tau_{A}^Y \subset \tau_{A}^X$  $\supset$: Let $U \cap A \in \tau_{A}^X$  $U\in \tau \iff U \text{ open in } X$   But $U \cap Y$ open in $Y \iff U \cap Y \in \tau_{Y}$  Hence $(U \cap Y) \cap A \in \tau_{A}^Y$ since $U \cap Y \in \tau_{Y}$  Therefore $U \cap A \in \tau_{A}^Y$  Hence: $\tau_{A}^X \subset \tau_{A}^Y$  Therefore: $\tau_{A}^Y=\tau_{A}^X$


QGIS 2.2 Print Composer - pointer will not select or move items

I refer to the questions at  and   My question may be a duplicate, but the answer given in the first of those questions will not resolve the issue I am experiencing. If the CRS thing from the second one is a more likely cause, I would like a clear explanation.  I am using Windows 8.0 and the CRS of my map is EPSG 27700  It happens most often when I select my label, but it can be after selecting other items. Everything freezes on the layout - the selection pointer has no effect. I can add new items, but I can't move them or select anything else. I can select all or deselect all using the menu command, but still the pointer has no effect when clicked on the layout. I can lock and unlock using toolbar buttons, but not with a right click. I can use toolbar buttons to send selected items to back or front, but it makes no difference to the lack of pointer click functionality.  If I open a new print composer from my template, or if I close and re-open QGIS, the composer may work ok for a while, but then the same thing happens again. It was more intermittent, but today it is happening almost immediately every time.  I have disabled all my plug-ins, but it made no difference.


Why is this Targaryen not immune to fire?

We know that Jon Snow is the son of Rhaegar Targaryen and has Targaryen blood running in his veins. Also, we have earlier seen that he is not immune to fire, unlike his aunt Daenerys. Why is this so? Is he not a true dragon?


Server login attempts NOT blocked after configuring fail2ban

So, I installed (and configured) fail2ban on three Ubuntu VPS servers. I configured (imo) a maximum of 3 failed login attempts (via Putty as root) within 2 minutes. Then I restarted the fail2ban service (according to ).    But when I look at my auth.log files in /var/log/ I still see 4, 5 or more failed attempts from certain IP's. So obviously I did something wrong as the IP is not blocked after 3 failed attempts.   It might have to do something with iptables, but that's where it gets a bit "foggy" for me..   Not sure how to setup a max-three-failed-login-attempts rule..  Additional: I see that the login attempts mostly have different ports for every attempt. Does that influence the count to max-three?  Because I see a port being "poked" twice and then no more attempts. Then the IP tries a different port (again 2 times). (all bots of course)


Square and square root and negative numbers

Are they equal?      -5 = $\sqrt{(-5)^2}$


What is cause of spots in image taken with dusty Nikkor AF-S DX 18-200mm ED VR II?

Dust or pollen inside this lens is common problem so I finally removed the front element and cleaned it, but even after this procedure I have the very same specks in a video as before. So I guess it's the heavily polluted second element - but I'm not sure if I can clean it.  Someone mentioned that these elements are coated, but I can't find any documentation/evidence. Blower was not enough.  Can I clean it as normal front element lens?        EDIT: So it's the dirty sensor. I set F22 and made video with 18-200mm and 55-300mm and the spots are same.


Modify array keys of an associative array

I have this array   $the_posted = Array             (     0 => Array         (             0 => 1,             1 => 2,             2 => 3,             3 => 4,         ),      1 => Array         (             0 => 5,             1 => 6,             2 => 7,             3 => 8,         )  );   whose keys i need to modify.I trying  to modify the array keys like  $all_array_keys = array_keys($the_posted);   foreach ( array_keys($the_posted) as $k=>$v ) {   $all_array_keys[$k]= rand(); }    echo '<pre>';   print_r($all_array_keys);   echo "<hr/>";   print_r($the_posted);   echo '<pre>';   I get this result  Array (     [0] => 25642     [1] => 8731 )  Array (     [0] => Array         (             [0] => 1             [1] => 2             [2] => 3             [3] => 4         )      [1] => Array         (             [0] => 5             [1] => 6             [2] => 7             [3] => 8         )  )   The change in keys is not reflected in the final array.How do i make this work?.


I was trying to model a desk and came across a problem, I can't seem to solve. I wanted to create a simple bevel. I used Mesh > Edges > Bevel on a selected edge and got this result   Why is it not symmetrical? How can I make it symmetrical?  For reference, what I actually wanted:


How can I watch Netflix on 16.04 with either Chromium or FireFox?

I installed Ubuntu 16.04 on my laptop and want to watch Netflix on it. However, when I click on a show, it redirects me to their systems requirement page: "Netflix system requirements for HTML5 Player and Silverlight".  I have tried solutions for 14.04 and am able to view shows on my other faster 14.04 system.   Is there something new that needs to be configured for 16.04?  I am using a Lenovo Idea Pad Y570. It meets the minimum requirements for version 16.04.


I need to install the imsart package to submit my article to an IMS journal. I downloaded the zip file from the , but I do not know how to install this package. I want to install this package so I can use it in Scientific WorkPlace and Texmaker.


I need to show log $Fib_{n}$ is $\theta(n)$ by the Fibonacci numbers defined as   $$ F_n=F_{n-1}+F_{n-2}$$  for  $$ n \geq 2 $$ $ F_{0} = 0 $ and $ F_{1} = 1 $  I'm not sure how to approach this.   I can see it grows exponentially as I've shown a basecase for $F_{6}$.  Basecase for $F_{6}$:  $$ F_{2} = F_{1} + F_{0} = 1 + 0 $$ $$ F_{3} = F_{2} + F_{1} = 1 + 1 $$ $$ F_{4} = F_{3} + F_{2} = 2 + 1 $$ $$ F_{5} = F_{4} + F_{3} = 3 + 2 $$ $$ F_{6} = F_{5} + F_{4} = 5 + 3 $$  But how I prove it's true for log $Fib_{n}$ is $\theta(n)$ I don't know. Hope someone can help!


A friend and I are splitting a RTR Booster box, mostly with hope for some chase rares, but we also wanted to have some fun while opening.  What are some Draft modes that only require two people?


Is "even if..." followed by present or future tense?

Is it correct to say:     even if only James Bond will benefit from...   or      even if only James Bond benefits from...


How can you spawn ender dragon after you kill it?

I've killed the Ender Dragon, and I'd like to fight it again. How can you respawn the Ender dragon after you kill it?


In my project, I use easyui-layout, which has west and center region.  When i click easyui-linkbutton announcement, oat.php will return table content which will be included in cenDiv successfully.  Here is my js code:  function corpAnn() { var oaAnn="annIn";  $.ajax({         dataType:'html',         type:"POST",         url:"oat.php",         data: {oaAnn:oaAnn},         success:function(data)         {             $('#cenDiv').html(data);         }       }); }   Here is my html code:

  announcement
   Here is oat.php code:  echo '
'; echo '
'; ...... echo '
'; echo '
';   And then, I want to doubleclick table tr, which will call alert method.  But unfortunately,  it worked fail. Here is my js test code:  $(document).ready(function() {  $('#cenDiv').on("dblclick","#tbbs #bbs td",function(){     alert("thsTest"); }); });   I know when loading my main web page, tbbs and bbs id are not exit in DOM.So I should rebond them to cenDiv id.But I don't know how. Who can help me?


Powering down the display in XP with a command

Is there a command to power down the display in Windows XP? That is, a command that causes the video card to stop sending a signal to the monitor until input is received, much as power management does after a time.


How to autostart programs (Chrome, LibreOffice) with a system, but in background?

I guess I cannot do that with every program, but I expect that Chrome and LibreOffice can be "preloded" when the system starts. How to do that?  I have checked in Chrome settings Google Cloud Print and ~"after close stay in background as a service". It does not apply since when I close Chrome, there is none chrome-like process running in gnome-system-monitor. Chrome has been installed from Google website, not Software Center.  EDIT: Chromium installed via Software Center also do not start with a system or stay in the background when closed nor as a process or a service.


Is it true that water go down the drain counterclockwise in the northern hemisphere and clockwise in the southern

Many websites say that water drain in different directions in Northern, Southern hemispheres. Some people say that  Coriolis effect causes it.  Some people say that it's not true.


apt-get install linux-headers-`uname -r` Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package linux-headers-4.9.0-kali3-amd64 E: Couldn't find any package by glob 'linux-headers-4.9.0-kali3-amd64' E: Couldn't find any package by regex 'linux-headers-4.9.0-kali3-amd64'


I want to write a CV with LaTeX and I'm wondering if someone could help me and give the beginning code of this CV:    I will inspire myself from it.


Why can't I add comments on Stack Exchange The Workplace?

I noticed that, on SE The Workplace I can't leave any comment, not even on my own posts or answers to my own posts. I simply can't see the "add a comment" badge. I have 247 points and verified that I have the privilege of commenting everywhere.  What I have tried:   Logging out and back in. Did not work. Check other SE sites: on the other ones I can comment regoularly. Check SE The Workplace from another device: on my phone I can leave comments.   Does anyone have any idea Why I can't leave comments on SE The Workplace while on my PC?


How is Selenium RC different from Selenium Web driver and some good pointers for a naive beginner to learn to scripting please? Thanks!

I am a manual functional tester and I am keen on shifting my career from Manual testing to Automation testing using Selenium. What is the best way to begin with this goal of mine? Thanks!


Defining layer style for KML layer within OGR Virtual Format?

I have the following OGR virtual format data source, which includes a few GeoJSON files and one KML file:  <OGRVRTDataSource>   <OGRVRTUnionLayer name="union">      <GeometryType>wkbGeometryCollection</GeometryType>     <LayerSRS>EPSG:4326</LayerSRS>      <OGRVRTLayer name="AMDT_02_2014_Finland_FIR">       <SrcDataSource>AMDT_02_2014_Finland_FIR.kml</SrcDataSource>       <SrcSQL>SELECT *,'PEN(c:#FF00FF,w:10px)' AS OGR_STYLE FROM AMDT_02_2014_Finland_FIR</SrcSQL>     </OGRVRTLayer>      <OGRVRTLayer name="OGRGeoJSON">       <SrcDataSource>tsa2014.js</SrcDataSource>       <SrcSQL>SELECT *,'PEN(c:#00FFFF,w:10px)' AS OGR_STYLE FROM OGRGeoJSON</SrcSQL>     </OGRVRTLayer>      <OGRVRTLayer name="OGRGeoJSON">       <SrcDataSource>ctr2014.js</SrcDataSource>       <SrcSQL>SELECT *,'PEN(c:#FFFF00,w:5px)' AS OGR_STYLE FROM OGRGeoJSON</SrcSQL>     </OGRVRTLayer>    </OGRVRTUnionLayer> </OGRVRTDataSource>   Setting the layer style for the GeoJSON layers works fine when doing a ogr2ogr conversion to another format such as PDF. However, trying to set the KML layer style with <SrcSQL>SELECT *,'PEN(c:#FF00FF,w:10px)' AS OGR_STYLE FROM AMDT_02_2014_Finland_FIR</SrcSQL> seems to have no effect. Default black pen is used to draw the polygon outline:     Is there a way to change the style of a KML layer within OGR VRT file? At least the syntax above does not seem to work.  The KML file used in this question can be downloaded from .


Exercise requires to simplify this sum: $$\sum_{k=0}^{20} \binom{50}{k}\binom{50}{20-k}$$  Tried to figure this out with no success. I have only final answer, which is $\binom{100}{20}$.  Please help me figure out the logic behind this simplification. Thanks!


How is it possible the universe expanded faster than the speed of light during inflation?

In a documentary written in collaboration with Stephen Hawking, the narrator (supposedly Stephen Hawkings) says that by the time the cosmos was 10 minutes old, it had already expanded thousands of light years in diameter. How is it possible that matter was traveling faster than light?


Does car tire pressure change with weight of car load?

Does tire pressure measured by a meter on tire gauge change with load? (I am not interested in pressure produced by car tires onto the road).  Car spec usually says "inflate to 220kPa normal load, 300kPa full load". Does this mean the measured pressure should be 300kPa only after the car was loaded, or can one inflate the tires to the recommended 300kPa while empty and then load the car with 500kg without needing to re-measure the pressure?  There are basically both answers to be found when researching the non-physics forums on the internet:   One explanation says that the tire will compress under bigger load, making the volume inside the tire smaller, hence pressure higher. It also states this is the reason why the spec plate in the car has two values - you should simply expect to measure higher pressure on the tires while the car is loaded. There are also explanations stating that the air does not escape from the tire, hence the amount of air inside the tire is constant and the pressure measured on the tires is constant even if the car is loaded (and based on observations, tires normally compress when the car is loaded). This would mean one needs to put more air into the tires when the car is loaded to ensure higher pressure.   To a layman, both sound feasible.  Is one of the explanations simplifying based on normal load assumptions? (i.e. tire pressure does not change if car is loaded with at most 1000kg, but would change if there was an enormous load put on the car?)  Where is the truth?


I am looking for a specific word to describe a person with a narrow perspective, suggesting a lack of foresight/consideration of the broader implications of their decisions.  This would preferably be the noun-equivalent of "myopic," as in:  I am most concerned with the politician's "myopic-ness" and total disregard for the broader implications of his policy proposal.


16.04 install freezing with watchdog: BUG: soft lockup - CPU#6 stuck for 22s

I am trying to install Ubuntu 16.04 on a new Dell XPS 15, 16gb Ram, i7 7700 CPU, 512gb SSD.  Windows is already preinstalled which I want to keep for the odd admin task so I added a partition of 220gb for my main Ubuntu machine. I have tried installing using the same boot drive I used on my new PC about 2 weeks ago which worked fine on there but I am just getting numerous errors when trying to install on this new machine.     I also tried installing the latest elementary OS with similar issues.  As the console was mentioning CPU I downloaded and ran the intel processor test and everything came out fine. Windows is also running well, or as well as it does so hardware seems fine.  Any ideas on how to resolve this?  I have tried three different usb drives all with the same result and also multiple ports on the machine itself.


Let $v_1, \ldots, v_r$ be non-zero elements of a vector space such that $\langle v_i, v_j \rangle = 0$ if $i \neq j$. Show that they are independent

Found this question in "Introduction to Linear Algebra" by Serge Lang, it says  Let $V$ be a vector space with a positive definite scalar product. Let $v_1, \ldots, v_r$ be non-zero elements of $V$ which are mutually perpendicular meaning that $\langle v_i, v_j \rangle = 0$ if $i \neq j$. Show that $v_1, \ldots, v_r$ are linearly independent  This makes intuitive sense to me, however I don't see where to start. If this was dot product in $\mathbb R^n$ I think I could work it out by using the coordinates of each vector, but as given, this problems seems like too general for me to tackle. Any hints?


Half Bridge Gate Drive Transformer - Extra winding?

I've been experimenting on a lot of half-bridge-based PC PSU schematics. There's one thing I cannot understand:    As can be seen from above, there's an extra winding in series with the high side driving winding (marked with red ?) and one end of it goes directly to the primary of power transformer.  What is its purpose?  Thanks.


How to resolve a '"file" is damaged and can't be opened' problem on Catalina?

This error message continually pops up, "geohxjhmvzab" is damaged and can't be opened.  I have searched, via FINDER, for the file, but to no avail.  I have also attempted to delete the file via TERMINAL, using an xattr command, to no avail.


I'm new to LaTeX and I'm just starting to create my own little template. I'm putting comments everywhere to make it easier to remember what command does what.  I'd like to have a seperate file that does not contain those comments though. Is there any easy way I can delete all comments from a .tex file?  Thanks


When a file is deleted, its contents may still be left in the filesystem, unless explicitly overwritten with something else. The wipe command can securely erase files, but does not seem to allow erasing free disk space not used by any files.  What should I use to achieve this?


Treat tab characters in code blocks as 8 spaces

People have asked similar questions in the past:  is from September 2012  I haven't found a single post where someone used a tab character and intended for it to be anything other than 8 spaces.  On the other hand, I've seen numerous edits where people have to correct the indentation because of how tabs are handled.  Should tabs be treated as 8 spaces?


Simulteneity & Irrelevance of Frame Choice

Let’s assume I measure time t in my rest frame - thus in a moving frame I have t’ corrected according to the Lorentz factor.  I have a moving primed frame such that t’= 0.5t for example.  I measure 1 second in my rest frame, which is observed as 0.5 second in my primed frame.  If I now consider my primed frame to be the rest frame, and my previous rest frame to now be my “primed” frame, and measure 0.5 seconds in my now rest frame, I get 0.25 seconds in my now moving frame. How does that work out? Shouldn’t I get my whole 1 second back?  It is safe to assume I could consider any possible frame of reference, so what detail is it that I’m missing?  Edit*: I have 2 pairs of frames:  Rest1: Let time be t Motion1: moving observer relative to Rest1 such that t’=.5t  Rest2: chosen such that Rest2 is at same speed as Motion1. Let time be T Motion2: chosen such that Motion2 is at same speed as Rest1. T’ =  0.5T  If t = 1, then t’=0.5 Since Rest2 and Motion 1 are at the same speed, then T = t’ = 0.5 Therefore T’ = 0.5*0.5 = 0.25  Motion2 and Rest1 are at the same speed, thus T’ = t, 1=0.25!?


Use integration to prove that $$n! = \Theta\left(\sqrt{n}\cdot\left(\frac{n}{e}\right)^n\right)$$   I managed to prove that $n! \leq en(n/e)^n$, by applying $\ln$ to both sides and integrating on the function $\ln$. In a similar way, I showed that $n! \geq e(n/e)^n$.  I can't find a way to get a tighter bound. Does anyone have an idea?


Is it possible to accumulate a set of statistics that describes a large number of samples such that I can then produce a boxplot?

I must clarify immediately that I am a practicing software developer, not a statistician, and that my college stats class was a very long time ago…  That said, I would like to know if there is a method for accumulating a set of descriptive statistics that could then be used to produce a boxplot, that does not entail storing a bunch of individual samples?  What I am trying to do is produce a graphical summary of queue service times within a complex multi-queue process. I have in the past used a package called tnftools that allowed large samples to be accumulated and then post-processed into a nice graph of response times and outliers… But tnftools are not available for my current platform.  Ideally I would like to be able to accumulate a set of descriptive statistics "on the fly" as the process runs, and then extract the data for analysis on demand. But I cannot simply have the process accumulate samples as the memory / IO involved in doing so would have an unacceptable impact on the performance of the system.


Is my MOSFET-based bidirectional level shifter insane?

In a moment of cheapness, I decided not to order a 5v to 3.3v level shifter from Sparkfun, but instead to put it together myself.  The  used a  MOSFET, but since I enjoy surface-mount soldering about as much as root canal treatment, I decided to use a  that is through-hole mounted and easily available from my preferred supplier.  The results of this were sub-optimal.  When pulling the 5v line to ground, all was fine - the 3.3v side went to 0.07v.  But when pulling the 3.3v to ground, the 5v line showed around 4.14v (it was otherwise a touch above 5.1v).  On a closer reading of the datasheets involved, as well as the original Philips application note on the subject, I began to come to the conclusion that the gate threshold voltage was the problem.  By altering the schematic and tying the MOSFET's gate to 5v instead of 3.3v, both sides seem to work fine.  Pulling either side low causes the other side to go low.  I'm not, however, at all confident that this is actually a sane thing to do.  My understanding of the original schematic isn't deep enough to form a sensible opinion.  Will this modified schematic work, or are the current good results I'm seeing mere fluke or a precursor to something releasing magic smoke?


Is it possible to copy my accounts and put them on the computer version on Skyrim?

Recently, I have been wanting to download the PC version of Skyrim. I was wondering, "Since I have two Orcs around level 36, and two other people and I don't want to restart all over again, is there a way to migrate or take my accounts and put them on the PC version?". So...now I am here, asking this question.


Where did the "unavailable" meaning of "Out of Pocket" come from?

The phrase "out of pocket" is often used in my office to mean "unavailable".  I've found  to this on the internet as well, but no obvious clue to where this meaning comes from.    Where does this particular meaning come from?


What way is the best way to hash a password?

I'm working on a website that should be very safe for the users, so I need the hash the passwords. Usually I'm using the MD5, but I read that it doesn't safe anymore. So I tried PHPass, but then I read that it also has been cracked. So I tried password_hash() of PHP 5.5, but I use HostGator, and the PHP there is 5.4. Also I want to be able to add salt without knowing it (like time() * userid()), like in the password_hash().   The hash strength is very important to me because I want to be 100% sure that my users are safe. So is there a way that very safe and not something like SHA that will be hacked soon?


Why can't we have same return type as . instead as ->?

Why we can overload -> and not . operator? Both are member access operator and has same significance.  I have read some reference from     AND    but still my doubts remains the same why we can overload .operator while not ->?   Is it because -> operator implicitly gets the reference of the returning pointer and thus making the call as the chain calls  struct X {     int foo; };  struct Y {     X x;     X* operator->() { return &x; } };  struct Z {     Y y;     Y& operator->() { return y; } };  Z z; z->foo = 42;          // Works!     z->foo = 42; This call is converted to ((z.operator()).opeartor()).operator() and thus value of foo is set to 42.  If I take this point I still have two more points,  1) why can't .(dot) operator works this way?  2) What if -> operator do not returns the reference to the class Y? Will it be a compilation error in that case?


How do I convert multiple lists inside a list using Python?

I want to convert multiple lists inside a list? I am doing it with a loop, but each sub list item doesn't get a comma between it.  myList = [['a','b','c','d'],['a','b','c','d']] myString = '' for x in myList:     myString += ",".join(x) print myString   ouput:  a,b,c,da,b,c,d   desired output:  a,b,c,d,a,b,c,d


That's how I try to do it.  read -p "enter ip " ip  if [[ $ip =~ ^[1-255].[1-255].[1-255].[1-255]$ ]]; then echo "good"; fi   Only work if the input is 1.1.1.1


How do I find the thread diameter of my lens?

I have an older Olympus OM 50mm lens that I'd like to get a matte box for, as I'm going to use it for video on a 550D. However, I can't seem to figure out what the thread diameter is. There are no markings on the lens itself to indicate what diameter. How do I figure this out?    Here's the lens I have. It's the standard 50mm ƒ/1.8 kit lens that came with many Olympus OM lenses in the '80s


I want to be able to catch every exception of my program and show it in a MessageBox, rather than the program to just say "Has stopped working".  For some reason - everytime something fails in the software - the program says stopped working. I want to be able to show it in a MessageBox, like in Visual Studio. How is it possible?  C# WinForms.


How do I choose a point and shoot camera under $400?

I need a P&S camera for my family. They would probably use it for family functions,trips etc. I want a camera with flash for taking good night photos with a decent quality. They are not technically inclined and I dont want much manual features apart from the normal modes (potrait,sports,landscapes). Decent picture quality for normal conditions is the criteria I am looking for. If the camera looks little big, it is an added advantage.  I have looked at few models like Fujifilm Fine Pix F800 EXR, the Panasonic Lumix DMC series and a Nikon P510. But I am confused with all the options and the different reviews on different sites. My thinking is that for a point and shoot camera, it is better to consider brands other than Nikon and Canon since they may provide better value for money.   Can someone recommend some good resources for analysis and what kinds of cameras I should consider - a bridge camera, a basic point and shoot, or some other type?


Proof of one of the transpose matrix theorms

Given an $m\times n$-matrix $A$ and an $n\times p$-matrix $B$. Prove that $(AB)^T = B^TA^T$.   I cannot find any proof of it. Could someone explain it please?  I tried and ended up with $A_{ji}B_{ji}=B_{ji}A_{ji}$.


Should I cover up my tattoo when visiting the Middle East?

I stumbled upon  in Egypt, in which one user warns that Egyptians regard tattooed people as criminals or foreigners.  How big of a problem will tattoos be for a regular tourist? Obviously you should cover your ink when visiting a mosque or a fancy restaurant, but I'm thinking more in general.  Is this a general opinion of the people in the Middle-East or Arabian countries? Is it tied to religion (and therefore also in other muslim countries) or culture?  I will be travelling to Egypt soon, and I have a tattoo that is visible even in short sleeves. I am also considering a simple skull-and-bone tattoo, which will be covered in short sleeves, but not when I lose the shirt on the beach, when trekking or whatever.


what's a word for someone who accuses you of something just because they're doing it themselves?

What's it called when someone blames you or accuses you of doing something because they're doing it themselves? For example, when your boyfriend/girlfriend is cheating on you, so they assume you're also cheating on them. I remember finding a word for it, but I can't seem to find it anymore...


Can "childs" ever be the plural of "child", in standard English?

Is the word childs ever used instead of children for the plural of child? And was it ever a part of standard English vocabulary but later neglected?


Tried - sudo apt update  sudo apt-get install python3-setuptools  giving error - E: Package 'python3-setuptools' has no installation candidate  Tried - sudo apt update  sudo apt install python3-pip  giving error - E: Package 'python3-pip' has no installation candidate  When checked for universal repository - sudo add-apt-repository universe  'universe' distribution component is already enabled for all sources.  For any other command too, giving error as python3-packagename has no installation candidate. I checked the version of python, it is 3.8.2 . I installed 3.9 now and how to make it default. I want to try it so that whether it may works.


Different methods to run a non-nixos executable on Nixos

What are the different methods to run a non-nixos executable on NixOs? I'd like to see also the manual methods.


"Interested with the course" or "interested in the course"?

Interested in/with the course   Which preposition is correct? in or with, or both.


I am in search of a term that describes movement, or practice of motor skills, as a factor of laterality. Would "kinesiological" be appropriate? I'll leave my two previous questions down below; hopefully it can shed more light. Thank you so much!