Why I can favorite a question but not an answer?

This question is not a duplicate of  or  because non of answers provided for these two actually answers this question. I want to favourite (not: bookmark) an answer, that isn't the top one and isn't that good to deserve to be top one. But, still, it is enough important for me to favorite it. I can't! Why?  . Answer in important to me, but may not be same good to others. Plus, my single vote won't bring it to the top.  . Answer can be very deeply in the list, or on another page, and it's position will vary from time to time.  . I don't want to mess with my bookmarks for this single purpose and because I strictly ask about favoring not bookmarking an answer. So I'll be able to access from my profile, not from my bookmarks bar. I'm allowed to have such desire, right?   Once again, this question asks, what are the reasons behind not implementing such obvious feature so far. It does not asks (as linked ones), how to work-around this missing. And as a :  Questions are merely the sand that produces the pearl.  Since , then why the hell we can't favorite them? Why we're limited to questions only? EDIT: Too many people suggests here, that favorites works like bookmarks, and that is, why we don't need to favorite answers, but we can favorite questions. They don't. Not for me and not for others (probably). If any argument said here (like cluttering bookmarks bar with countless number of bookmarks) does not convince you, then let me put that this way: favorites are public, so I can express my point of interest to others; bookmarks are my own, private (and thus sucks!)


Linking to /?lastactivity breaks when that activity is on second or greater page

When viewing posts by recently active, the last action can generally be linked to directly by clicking the "answered/modified" link. For example, the "answered 5 hours ago" text circled here:    Clicking this takes you to the link https://meta.stackexchange.com/questions/312850/the-second-draft-of-our-code-of-conduct-is-available-for-feedback-and-review/?lastactivity  It seems, however, when that /?lastactivity (either answered or modified) occurs somewhere other than the first page of answers, linking directly to the post fails and, instead, links to the question itself. This makes finding the recent activity difficult, particularly when there are many pages of answers. Yes, I can sort the answers by active but not everyone realizes that's an option.  I've reproduced this on , so it's not an MSE-specific issue nor is it apparently related to the responsive layout. I've also seen this behavior on answers that were answered, edited, or deleted.    To reproduce:   Find a question on the Home or Questions/Active page with >30 answers. Click on the last activity link next to the username of the person who performed that action   Using PPCG questions with >60 answers that are newly answered is the most likely to consistently be a good choice as new answers to questions with many existing answers are unlikely to have surfaced above the latter page/s.  See that the end result is identical to loading the question link/does not take you to the answer.   I suppose that it's possible there isn't a way to fix this but, if there is, it'd be nice to have.


Can I Install packages or softwares to live Ubuntu USB Drive?

I am using a 160GB HDD installed Windows 7, and I want to use Ubuntu Linux temporary in my System, Can I install softwares in the Live USB permanent while using it.  Like Tor Browser I want it every time when I use my USB stick again and again.   Any Help is appreciated.


Cannot duplicate all ouput to a file with tar/pigz

I'm using in my script:  tar cfh - "$SRC_DIR" --exclude-from <(find $SRC_DIR -size +$EXCLUDE_MB_FILES) | pigz -9 --quiet --keep --recursive --rsyncable > $BACKUP_TARGER_DIR/$ARC_NAME | tee $LOG_FILE   But LOG_FILE is empty. Why?


Is this correct: "I'd have to have had..."

This sentence makes my head hurt a bit, and it doesn't seem right, but perhaps you guys could help me sort it out.     "If I would've gone to Canada, I'd have to have had some kind of winter gear."


Suppose $A$ is an $n\times n$ complex matrix. How to show the following two properties   If $\lambda$ is an eigenvalue of $A\bar{A}$, so is $\bar{\lambda}$. Here $\bar{A}$ means the entrywise conjugate of $A$. The algebraic multiplicity of negative eigenvalues (if any) of $A\bar{A}$ are even.


In Ubuntu 13.04 I used to use the ppa:upubuntu-com/tor64  PPA to install the 64-bit Tor Browser Bundle. However, in Ubuntu 13.10 it doesn't work anymore. How do I install the Tor Browser Bundle in Ubuntu?


Can I buy a PS4 game if I own the free version?

Say I have a PS4 subscription and a free monthly game. What happens if I decide to cancel my subscription, but decide to buy the previously free game (so I won't need the subscription to play it).   Can I buy a game outright without getting the 'you cannot buy this because you already own...' error?


Is there a certain size tube for my tyres?

When it comes to fixing bikes, i'm not to crash-hot. I can clean grime, oil the chain and put it back on if it falls off. However, when it comes to the inner tubes I usually rely on someone else to get me another tube and put it on for me (I can put them on, but in that sense I'm too lazy). So, today, when I went to pump up the tyres I found they had a puncture and I would prefer to change them as I haven't ridden this bike in a LONG time, only I'm not sure if there has to be a certain size tube. Help? Please? :)


How to install wlan driver mt7601u ? file(mt7601Usta.ko) is missing while doing it?  i am facing a problem while setting up wlan connection for my new mediatek wlan adapter .   unable to setup the connection , while making it was showing that file is missing .  when i replaced the file which is downloaded externally from online , it is prompting as a invalid file .  help me to go wireless


Test class not sure how to write for this code

I have written following apex class:  public with sharing class Persmissionset {     @AuraEnabled  public static PermissionPagerWrapper fetchPermission(Decimal pageNumber ,Integer recordToDisply) {       Integer pageSize = recordToDisply;       Integer offset = ((Integer)pageNumber - 1) * pageSize;      // create a instance of wrapper class.     PermissionPagerWrapper obj =  new PermissionPagerWrapper();     // set the pageSize,Page(Number), total records and accounts List(using OFFSET)            obj.pageSize = pageSize;         obj.page = (Integer) pageNumber;         obj.total = [SELECT count() FROM PermissionSetAssignment Where Assignee.isActive = True AND permissionSet.IsOwnedByProfile = FALSE];         obj.permissonAssignment = [SELECT PermissionSet.Name, PermissionSet.Id, PermissionSet.Label, Assignee.Name, Assignee.Id, Assignee.Profile.Name,Assignee.ProfileId,Assignee.UserRole.Name,Assignee.Profile.UserType,Assignee.Email FROM PermissionSetAssignment         Where Assignee.isActive = True AND permissionSet.IsOwnedByProfile = FALSE         ORDER BY Assignee.Name LIMIT :recordToDisply OFFSET :offset];     // return the wrapper class instance .         return obj;      }   // create a wrapper class with @AuraEnabled Properties      public class PermissionPagerWrapper {     @AuraEnabled public Integer pageSize {get;set;}     @AuraEnabled public Integer page {get;set;}     @AuraEnabled public Integer total {get;set;}     @AuraEnabled public List<PermissionSetAssignment> permissonAssignment {get;set;}    }   But here  I am stuck in writing test class for this object.  Can some one help here as of now I am writing this test class but its giving error for me:  @isTest public class PermissionsetTest {   static testMethod void PermissionTest()   {  List<> saList = Persmissionset.fetchPermission(10 ,100);    } }


We are told the universe is expanding at anything between 68 and 73km per second, per megaparsec (depending on the places you look) - so by association, the space between us and anything else out there is also expanding, right?    Can anyone tell me if there has been any indication that expansion is a potential variable for any orbital change in our solar system? As the universe expands, does, as a result, the space between atoms/molecules/planets then also expanding etc.? I've heard all sorts of stories about the expansion of the universe...   it is faster than previously thought.  it is increasing in speed.  recently, I came across a publication from Oxford University from Oct 2016 that suggests it is staying at a constant speed.      I'm now waiting for it to slow down.  has anyone on here worked for or experienced first hand the collecting of that data (or similar), and possibly explain why they think so many different conclusions are being drawn from this subject. as I think I'm right in saying that they analyse the light from collapsing stars and measure their brightness.   Could this mean that the universe is expanding at different rates?


Issue with "ureadahead" and "util-linux" packages

My system is encountering issues while processing packages ureadahead and util-linux:  root@sait32:/home/sait32/Downloads# sudo dpkg --configure -a dpkg: error processing package ureadahead (--configure):  package is in a very bad inconsistent state; you should  reinstall it before attempting configuration dpkg: error processing package util-linux (--configure):  package is in a very bad inconsistent state; you should  reinstall it before attempting configuration Errors were encountered while processing:  ureadahead  util-linux   Can anyone please help on how to resolve this?


number of nonnegative integer solutions of linear equation $ x + y + z = n$, where $x\le y\le z$

I know the answer for the cases where I can have all possible values which will be given by $(n+k-1)C(k-1)$ but I don't know how to reduce it to the given constraints.


The more general version of this theorem in Munkres' 'Topology' (p. 290 - 2nd edition) states that   Given a locally compact Hausdorff space $X$ and a metric space $(Y,d)$; a family $\mathcal F$ of continuous functions has compact closure in $\mathcal C (X,Y)$ (topology of compact convergence) if and only if it is equicontinuous under $d$ and the sets  $$ \mathcal F _a = \{f(a) | f \in \mathcal F\} \qquad a \in X$$  have compact closure in $Y$.  Now I do not see why the Hausdorff condition on $X$ should be necessary? Why include it then? Am I maybe even missing something here (and there are counterexamples)?  btw if you are looking up the proof: Hausdorffness is needed for the evaluation map $e: X \times \mathcal C(X,Y) \to Y, \, e(x,f) = f(x)$ to be continuous. But the only thing really used in the proof is the continuity of $e_a: \mathcal C(X,Y) \to Y, \, e_a(f) = f(a)$ for fixed $a \in X$.  Cheers, S.L.


how i can parse array of objects as one string to objects in javascript


Are feats explicitly Extraordinary by default?

In both Pathfinder and D&D 3.5e that it’s based on, abilities are often tagged as extraordinary (Ex), supernatural (Su), or spell-like (Sp). There are a few other categories (e.g. psi-like abilities, marked Ps), and some things that either go unlabeled or have their own category (e.g. spells).  Both games also have feats, special abilities that can be selected once every few levels by those who meet their requirements.  In 3.5, there is a lot of precedence suggesting that feats are extraordinary (Ex) unless the feat description and/or the description of its explicitly says otherwise. Book of Exalted Deeds suggests it by specifying that Exalted feats are supernatural, unlike other feats. Complete Champion does likewise with a number of its Domain feats. In fact, I could swear I remember reading an explicit statement to this effect.  In Pathfinder, things seem vaguer, and I cannot find any statement about the default category of feats (though, I also cannot find any such statement in 3.5e).  Does anyone know if there are any explicit statements in the published rules for these systems that feats are extraordinary unless otherwise specified? An acceptable answer must address both systems, and must either cite a quotation from an authoritative source or else indicate how sure we can be that there is no such default for each system.


I was reading about CPU fetch time, where I found that CPUs take much less time to access data from RAM as compared to accessing a hard disk, and that RAM is present for storing the information and data of executing program.  Then I wondered about what will happen when we only use a hard disk but no RAM?


Can $x^{n}-1$ be prime if $x$ is not a power of $2$ and $n$ is odd?

Are there any solutions to $x^{n}-1=p$ with p prime, integers $x,n>1$ and $x$ not a power of $2$?  $x$ must be even. $n$ is odd since if $n=2m$ then $p=x^{n}-1=(x^{m}+1)(x^{m}-1)$ hence $p=x^{m}+1$ and $1=x^{m}-1$, which has solution $p=3$ given by $x=2^{2}$.   This generalises; for any solution to $x^{n}-c^{2}=p$, $n$ must be odd. And for any solution to $x^{n}-c=p$, $x$ is odd iff $c$ is odd unless $p=2$ and, if $a$ divides $c$ and $p$ does not divide $c$ then $x$ divides $c$.


Restarts to install menu with usb in. Restarts to black screen and flashing underscore with usb out

So i'm trying to install Ubuntu 14.04 and I can install Ubuntu, but when it restarts with the USB in, it acts like Ubuntu wasn't installed. It goes to the install, try, ect menu. When I take out the USB, after my pc says press ESC to go to boot options, it turns to a black screen with a flashing underscore. I've tried 2 different USB installers now.


How to solve the following sum? $2^0{n\choose 0} + 2^2{n\choose 2} + 2^4{n\choose 4}+\cdots+2^n{n\choose n}$

I am aware that ${n\choose 0} + {n\choose 2} + {n\choose 4}+\cdots =2^{n-1}= {n\choose 1} + {n\choose 3} + {n\choose 5}+\cdots$ but that's pretty much all I know about binomial coefficients.. Thanks in advance!


Identify question upon reputation loss from removed user

Understanding , it'd be nice to know specifically where that reputation was lost from.  Reputation changes typically cite where reputation was gained or lost; however, it's difficult to reference the origin of where it was lost when a user is removed:        Already labeled as removed, a link to the question would indicate the source of the loss, as in:     -10     6 hours ago     removed     List component to bring up InputText boxes   Perhaps there's greater complexity here than I realize, such as the question itself being deleted; however, actions such as removing an upvote to a question or answer could be linked.


macOS partition disappered after installing windows 10 using bootcamp

I use a macbook pro 2015 with macOS High Sierra. I installed windows 10 using bootcamp, which resized the macOS partition and created a 80GB windows partition. The machine boots into windows just fine.  Unfortunately I can't go back to macOS because the macOS partition is not selectable as a boot source in bootcamp and "boot into X" boots into windows again. When I start from recovery (ctrl+R) I can see both partitions in diskutil. I tried to repair the macOS partiton but it had no effect.  How can i resurrect the macOS partion so I can choose which OS to start?  Update: I can start macOS by booting with option/alt pressed and chose the mac partition.  diskutil list output:  Capsicum:~$ diskutil list /dev/disk0 (internal, physical):    #:                       TYPE NAME                    SIZE       IDENTIFIER    0:      GUID_partition_scheme                        *251.0 GB   disk0    1:                        EFI EFI                     209.7 MB   disk0s1    2:                 Apple_APFS Container disk1         170.0 GB   disk0s2    3:       Microsoft Basic Data BOOTCAMP                80.3 GB    disk0s3    4:           Windows Recovery                         503.3 MB   disk0s4  /dev/disk1 (synthesized):    #:                       TYPE NAME                    SIZE       IDENTIFIER    0:      APFS Container Scheme -                      +170.0 GB   disk1                                  Physical Store disk0s2    1:                APFS Volume Macintosh HD            101.3 GB   disk1s1    2:                APFS Volume Preboot                 20.2 MB    disk1s2    3:                APFS Volume Recovery                506.6 MB   disk1s3    4:                APFS Volume VM                      2.1 GB     disk1s4  /dev/disk2 (external, physical):    #:                       TYPE NAME                    SIZE       IDENTIFIER    0:     FDisk_partition_scheme                        *2.0 TB     disk2    1:                  Apple_HFS Passport                2.0 TB     disk2s1   thanks a lot for any clarification what is wrong!


I use tilda as my terminal on Ubunut 14.10. The trouble I have is that I want to have the tab bar, since the titles in it are actually useful for navigation, but having username@computer:~/some/folder is irritating. So I looked around, and yes, I can change bash's title so that it doesn't display the username and computer.  But that only partially solves the problem, because even if I only have the pwd as the title, it grows really fast. And I don't need the whole path, so I was wondering if there is a way to set the maximum size of the title. So that if I'm in   /home/username/Downloads/some_unzipped_folder/subfolder/   The title is displayed as   /home/usern...folder/subfolder/   depending on how much width I set, so that I get some useful information from the title, but not have my tab bar in tilda fill up quickly.


We let a>0 and b>0 and  we have $\sum_{n=0}^{\infty}b^n-a^n$. We have to find all values a,b>0 where $\sum_{n=0}^{\infty}b^n-a^n$ is convergent. I think I can use that $$\sum_{n=0}^{\infty} b_n < \infty , \sum_{n=0}^{\infty} a_n < \infty \implies \sum_{n=0}^{\infty} (b_n-a_n) < \infty. $$. And I think $\sum_{n=0}^{\infty}b^n$ and $\sum_{n=0}^{\infty}a^n$ is convergent if a<1 and b<1? It will make sense. But how can I show it?


How to merge one dimensional array and two dimensional array in php

I have two array one is two dimensional and second is one dimensional and want to merge in a two dimensional array.  For Example :  # array1 Array (     [0] => Array         (             [id] => 598                   )      [1] => Array         (             [id] => 599                 ) ) # array2 Array (            [id] => 66     )  #resultant array Array (     [0] => Array         (             [id] => 598         )     [1] => Array         (             [id] => 599         )     [2] => Array         (             [id] => 66                  ) )   In above example array1 and array2 are two input array and want to result as resultant array.  I have tried array_merge php function but it is not working.   How to do that?


What do you call a person who does not go to both the extremes of the argument but remains in the middle ground?

The kind of person who does not believe in the extreme sides and always weighs the pros and cons and comes to the conclusion that everything should be in moderation


creating a diagonal matrix with a variable amount of parameters

I'm currently working on writing something in latex that requires many usages of diagonal matrices of form   $\begin{bmatrix*}     \lambda_1 & 0 & 0\\     0 & \lambda_2 & 0\\     0 & 0 & \lambda_3\\  \end{bmatrix*}$   with a variable number of parameters \lambda.  Previously, I've found a script that helped me create vectors with multiple parameters and therefore save me from rewriting the matrix for them:  \newcommand{\vect}[1]{% \begin{bmatrix} #1\checknextarg} \newcommand{\checknextarg}{\@ifnextchar\bgroup{\gobblenextarg}{ \end{bmatrix}}} \newcommand{\gobblenextarg}[1]{ \\ #1\@ifnextchar\bgroup{\gobblenextarg}{ \end{bmatrix}}}   While this script works for vectors, I can't think of a generalized way to make something similar to this for diagonal matrices. Finding a script like that will save me a ton of time. I've tries using lualatex for this but I'm inexperienced with it and this doesn't help with trying to have a variable amount of parameters and a corresponding amount of 0s. What I hope for is for the example above, I would simply be able to do something like $\diagmat{\lambda_1}{\lambda_2}{\lambda_3}$ for any amount of parameters, similar to what I can do with \vect. While I'm not sure if this is possible, anything that can save me time and space in writing these matrices would be appreciated.


'Search on Yammer' link in search center refiners

I have a heavily branded site I'm working on and can't find where the "Search on Yammer" link is being populated from. It appears within the search refiner/filter web part in the left column but none of the display templates reference this.   I'd like to be able to customize the link, placement on the page, etc. without resorting to jQuery to move elements around the page.     And the markup coming through looks like this. The refiners themselves come through a series of display templates but the Yammer link is nowhere that I can see in any of them.

                     Search on Yammer

             ... refiners populated through display templates ...


How to mount two separate folder locations to one?

I am trying to connect two folders from two different locations to one folder from which radio software plays music.  This is what I have done so far:   In /etc/fstab I have put the following two lines:  /usr/local/centovacast/var/vhosts/adminaw/var/spool/media   /mnt/mounted-drive/awmusic_songs/   none   bind /usr/local/centovacast/var/vhosts/adminaw/var/spool/media   /home/centos/awmusic_songs_1/   none   bind  Then I have run the following two commands:  mount --bind /mnt/mounted-drive/awmusic_songs/ /usr/local/centovacast/var/vhosts/adminaw/var/spool/media mount --bind /home/centos/awmusic_songs_1/ /usr/local/centovacast/var/vhosts/adminaw/var/spool/media    So basically, the radio software reads music from /usr/local/centovacast/var/vhosts/adminaw/var/spool/media, and the songs are in the folders awmusic_songs and awmusic_songs_1.  After I have done what I have described above I only see files (songs) from the second folder (awmusic_songs_1).  Is it possible what I am trying to achieve? If so, could someone please help me?


Ways to evaluate $\int \sec \theta \, \mathrm d \theta$

The standard approach for showing $\int \sec \theta \, \mathrm d \theta = \ln|\sec \theta + \tan \theta| + C$ is to multiply by $\dfrac{\sec \theta + \tan \theta}{\sec \theta + \tan \theta}$ and then do a substitution with $u = \sec \theta + \tan \theta$. I like the fact that this trick leads to a fast and clean derivation, but I also find it unsatisfying: It's not very intuitive, nor does it seem to have applicability to any integration problem other than $\int \csc \theta \,\mathrm d \theta$.  Does anyone know of another way to evaluate $\int \sec \theta \, \mathrm d \theta$?


School in South Korea removed asbestos over the past few weeks. Now I am all paranoid.   Is this asbestos? Found these dime-sized chunks by my desk.          Higher resolution images are available here:    There should be 4 pics. If not clear enough let me know.


Dominated convergence theorem and uniformly convergence

I try to solve the following task:  Let $(\Omega,\mathfrak{A},\mu)$ be a measurable space and $\mu(\Omega)<\infty$. Let $(f_n)_{n\geq1}$ be a sequence of integrable measurable functions $f_n:\Omega \rightarrow [-\infty,\infty]$ converging uniformly on $\Omega$ to a function $f$. Prove that $$\int f d\mu = \lim\limits_{n\rightarrow \infty} \int f_n d\mu$$.  What I thought: uniformly convergence of $f_n \rightarrow f$ means that $f$ is continuous and therefore measurable. Now I thought that I could use the dominated convergence theorem to show the equality.  uniformly convergence means $\lim\limits_{n\rightarrow \infty} \sup \{|f_n-f(x)|:x\in \Omega\}=0$ so I think I can define a function $s(x):=\sup \{|f_n-f(x)|:x\in \Omega\}=0$ which dominates all the $f_n$ and apply the theorem. But I'm not sure, if this is the correct way.


I learned the following  $$ e^{ik2\pi}=1 $$  and I was wondering whether or not $k$ has to be an integer.    Thought 1: Since $e^{ik2\pi}=\cos(2k\pi)+i\sin(2k\pi)=1$, equating the real and imaginary parts we conclude that $k$ is an integer.  Thought 2: Since $e^{i2\pi}=1$, if we raise both sides to the power $k$ then we have $e^{ik2\pi}=1^k=1$ for any $k$. So $k$ does not have to be an integer.  I am more keen on Thought 1 but I would like to know what is wrong in Thought 2?


Is it incorrect to say that a Poisson distribution has a PDF?

Is it incorrect to say that a Poisson (or any discrete) distribution has a probability density function? I thought that a discrete distribution has a PMF and not a PDF.


$\int_{0}^{\infty}\frac{\sin^{2n+1}(x)}{x} \mathrm {d}x$ Evaluate Integral

Here is a fun integral I am trying to evaluate:  $$\int_{0}^{\infty}\frac{\sin^{2n+1}(x)}{x} \ dx=\frac{\pi \binom{2n}{n}}{2^{2n+1}}.$$  I thought about integrating by parts $2n$ times and then using the binomial theorem for $\sin(x)$, that is, using $\dfrac{e^{ix}-e^{-ix}}{2i}$ form in the binomial series.  But, I am having a rough time getting it set up correctly. Then, again, there is probably a better approach.   $$\frac{1}{(2n)!}\int_{0}^{\infty}\frac{1}{(2i)^{2n}}\sum_{k=0}^{n}(-1)^{2n+1-k}\binom{2n}{k}\frac{d^{2n}}{dx^{2n}}(e^{i(2k-2n-1)x})\frac{dx}{x^{1-2n}}$$  or something like that. I doubt if that is anywhere close, but is my initial idea of using the binomial series for sin valid or is there a better way?.  Thanks everyone.


Is there any term used for multiple hat tricks?

If a bowler takes more than three sequential wickets (say six wickets) in one over, would this be called as two hat-tricks or does this feat, however unlikely, has a different name?


I recently awarded with curious badge.  I get a notification like:    But when I checked my badges list, it is not there.     Is that a bug ? Can someone explain little bit about the criteria for achieving Curious, Inquisitive and Socratic badges ?


I know the definition of formal power series, power series and polynomials. But what does the adjective "formal" mean? In , does it mean "9. Of or relating to linguistic or logical form as opposed to function or meaning" or maybe another one in the link?   Or does "formal" have some mathematical meaning which is other than usual dictionary meaning?


I working in some project. I need get all classes with styles of any html element Example Element: <a href="#" class="btn btn-transparent-white font-weight-bold py-3 px-6 mr-2">     Agregar Medicamento </a>  Code JS var classes = e.target.className.split(' ');  console.log(classes);  Result: ["btn", "btn-transparent-white", "font-weight-bold", "py-3", "px-6", "mr-2"] With my code I can get styles of classes .btn transition: color 0.15s ease 0s, background-color 0.15s ease 0s, border-color 0.15s ease 0s, box-shadow 0.15s ease 0s;  .font-weight-bold font-weight: 500 !important;  .py-3 padding-bottom: 0.75rem !important;  .px-6 padding-left: 1.5rem !important;  .btn-transparent-white undefined  But I have a problem with combined styles for example .btn.btn-white-transparent Any idea how I can to search any coincidences of element? Edited: Thanks for you anwers but I can search single classes , my problem is when I want to search .btn-white-transparent. this is a combined style, I want to seach .btn-white-transparent and the anwer will be .btn.btn-white-transparent { color:#FFF}


Color difference between 2 objects in Object Mode/Solid View

Blender 2.79 Two objects with identical material settings and no texture. Viewed in Object Mode/Solid View the one on the left has a dark, bluish tint. The two look identical in other views and render with identical colors. But why the different colors in Solid View?  A minor but nagging and annoying nuisance. Much thanks from a newbie.


How to search for character from their personalities?

I have seen some anime and forgot some characters but remember some background information and the role played how to search for that?


After upgrading to Ubuntu 20.04, I have noticed any shortcut involving both Shift and Ctrl does not work if I Shift before Ctrl. In other words, Shift+Ctrl+T does not work but Ctrl+Shift+T works. This is true whether I use Chrome, Firefox, VS code or any other software. Needless to say, this is frustrating and I never experienced such issue before 20.04. Is this intended or have I messed up something?


Unplugged USB stick while formatting - now not recognized any more

I was formatting my USB memory stick using Ubuntu and chose "Override existing data".   I accidentally knocked the memory stick out of the USB port. When I put it back into my Ubuntu computer it was not visible in the file manager (Nautilus), and it does not appear in my unity dock.  I have already tried rebooting the computer with the memory stick inserted. But no effect.  What can I do to bring my memory stick back to life?


My approach is to solve this by induction.   Base case: $n=1$  $1^3 = 1^2 = 1$  Inductive Step: Suppose that  $1^3+2^3+...+n^3 = (1+2+...+n)^2$  holds for all positive integers $n$. We use that to show that  $1^3+2^3+...+n^3 + (n+1)^3 = (1+2+...+n+(n+1))^2$   $1^3+2^3+...+n^3 + (n+1)^3 = (1+2+...+n)^2 + (n+1)^3$  And here is where I can no longer proceed. I know there must be some trick/computation that I am not seeing that will make this proof easier. Help? Thanks!!


Suppose i have this hook_theme() in my module, choosing a template inside the module:        /**  * Implements hook_theme().  */  function module_theme($existing, $type, $theme, $path) {    return array(      'module-output' => array(        'template'  => 'output-template',        'variables' => array(),    ),  }   If i put the same output-template.tpl.php inside my active theme, Drupal picks up the module's template.  Is there a way to make Drupal understand that if a template with the same filename exists somewhere in the theme, to pick the theme's template and not the module's (like an override)?


If a group isomorphism is an involution with only a trivial fixed point, then the group is abelian

I've been struggling with the following problem. I don't really know how to tackle this, but I suspect that it is not hard at all.  Let $G$ be a group and $f\colon G\to G$ an isomorphism such that $f$ is an involution ($f^2=1_G$) and $e$ is the only fixed point of $f$ (that is, $f(x)=x\implies x=e$)  I must prove that $G$ is abelian.  How should I proceed here ?  The problem gives a hint: show that every element of $G$ can be written as $x f(x)^{-1}$. I suspect that then one can use some result like "$G$ is abelian $\iff x\mapsto x^{-1}$ is a group morphism  ", but I haven't tried yet because I don't see why the hint holds.  Any help is appreciated, thanks in advance!


Most of us will know that tapping "build number" a few times in "about device" gives us access to developer settings.  Is there a way to reverse this, and hide developer settings from the menu without doing a factory reset?


Where can I find source code for the Java data structures?

Not sure if this has been asked before, did some digging.  I'm trying to prepare for a few interviews, and I was just curious to see if how Java implements its data structures (arraylist, map), etc is public.


In Kleppner & Kolenkow's  (Amazon link), the general gyroscope motion including  was derived using the approximation condition $\Omega T \ll 1$ where $\Omega$ is the precession angular velocity and $T$ is the period of nutation.  How does one describe the gyroscopic motion if the the condition for the approximation is not satisfied? How does one describe the general gyroscopic motion if    the angular momentum of precession is not negligible and  if the gyroscope spins very slowly around its axis, $\omega$ is low?   In general I want to find the formula for most general gyroscope motion. If I let $\omega$ go to zero then I should get the special case of a pendulum.


After doing chmod 400 on /usr the sudo command is not working

I changed the permission of the /usr to 400 and now I am not able to use sudo. How do I revert this and fix it?


Clickable footnotes/anchors should be a thing

Essentially, a link that can be made to reference another point in the same post, and clicking on that point leads the other way around.   However, you can only reference your own post, and not anywhere else on the page, and you will be notified if the anchors break before you submit an edit, so that you can fix them.


Proving an inequality involving factorials: $(\frac{n}{2})^n \ge n! \geq (\frac{n}{3})^n$

For $n \geq  6$, where $n$ is a natural number, prove that $(\frac{n}{2})^n \ge n! \geq (\frac{n}{3})^n$.  I tried using induction but could not do it.


I'm currently looking to buy a lab power supply. But there's something I wonder.   We can adjust the voltage and the current.  Let's say I have a circuit requiring 9V and draining 1A.  What if I setup my power supply to 9V 2A ? I think the circuit will only use 1A from the two available and the power supply will warm for nothing but the circuit will not be damaged. Can you confirm this ?


$f(x) = x^5-x^4+x^2-x$ on the interval $(-\infty,\infty)$  The teacher told us that we would have to use Newton's method to solve this problem but I am not sure what to do after taking the derivative.


Calculate $E(Y)$ and $Var(Y)$ given the random variable which is exponentially distributed

The random variable $X$ is exponentially distributed with parameter $\lambda = \dfrac{1}{2}$. Also, define $Y = -2X + 1$. Calculate $E(Y)$ and $Var(Y)$.  So we have   $$f_X(x) = \dfrac{1}{2} e^{-\dfrac{1}{2}x} $$  if $x\ge0$ and $0$ otherwise.  But how to calculate $E(Y)$ and $Var(Y)$ ?


When to use lambda, when to use Proc.new?

In Ruby 1.8, there are subtle differences between proc/lambda on the one hand, and Proc.new on the other.    What are those differences? Can you give guidelines on how to decide which one to choose? In Ruby 1.9, proc and lambda are different. What's the deal?


Why does the MXtoolbox SPF record checker not like my SPF record?

I have a shared hosting server and have been spilling my brains out trying to find a SPF record that is globally accepted by other hosts.  Let's take the domain gimsid.ro. Which can send mail to any domain, except one of our clients, which denies meessages because of incorrect SPF record.  Now, when I check with the Kitterman tool (at kitterman.com) it says that it passes all the tests.  When I check with MXtoolbox () is says that it's not valid.  I always try to use a SPF record like this:  example.com -- v=spf1 a mx ip4:12.34.567.89 mx:example.com ~all   where 12.34.567.89 is the IP I have assigned to that domain.  Am I doing something wrong ? Is there a "globally accepted" SPF record?


Prove that $A=B$ considering: $(A \cap C = B \cap C) \land (A \cup C = B \cup C)$

So this is the thing I've got to prove: $ (A \cap C = B \cap C ) \land ( A \cup C = B \cup C ) \Leftrightarrow A = B $  I can understand this intuitively but the formal proof is taking me some time. So far, I've got this:   $ (A \cap C \subset B \cap C ) \land (B \cap C \subset A \cap C ) \land ( A \cup C \subset B \cup C ) \land ( B \cup C \subset A \cup C ) \Leftrightarrow (A \subset B) \land (B \subset A) $  $ (\forall x) (x \in A \land x \in C \Leftrightarrow x \in B \land x \in C ) \land (\forall x) (x \in A \lor x \in C \Leftrightarrow x \in B \lor x \in C ) \Leftrightarrow (\forall x)(x \in A \Leftrightarrow x \in B) $  But I feel like going nowhere. I assume this has something to do with the transitive property, but I'm not sure how to apply it here.


I've basically re-written the terminal output instead of appending a series of edits to this question:  root@doge:/etc/cron.d#  root@doge:/etc/cron.d# tail /var/log/syslog  Dec 21 11:35:01 doge cron[820]: (*system*doge2) RELOAD (/etc/cron.d/doge2) Dec 21 11:35:01 doge cron[820]: Error: bad username; while reading /etc/cron.d/doge2 Dec 21 11:35:01 doge cron[820]: (*system*doge2) ERROR (Syntax error, this crontab file will be ignored) Dec 21 11:38:01 doge cron[820]: Error: bad command; while reading /etc/cron.d/doge3 Dec 21 11:38:01 doge cron[820]: (*system*doge3) ERROR (Syntax error, this crontab file will be ignored) Dec 21 11:56:01 doge cron[820]: Error: bad command; while reading /etc/cron.d/doge4 Dec 21 11:56:01 doge cron[820]: (*system*doge4) ERROR (Syntax error, this crontab file will be ignored) Dec 21 11:56:01 doge cron[820]: (*system*doge) RELOAD (/etc/cron.d/doge) Dec 21 11:56:01 doge cron[820]: Error: bad command; while reading /etc/cron.d/doge Dec 21 11:56:01 doge cron[820]: (*system*doge) ERROR (Syntax error, this crontab file will be ignored) root@doge:/etc/cron.d#  root@doge:/etc/cron.d# cat doge * * * * * /home/digger/webxass root@doge:/etc/cron.d#  root@doge:/etc/cron.d# cat doge2 * * * * * /home/digger/cpuminer/minerd -o stratum+tcp://doge.pool.webxass.de:3333 -O <user>.<worker>:<worker_password>  root@doge:/etc/cron.d#  root@doge:/etc/cron.d# cat doge4 * * * * * /home/digger/webxass root@doge:/etc/cron.d#  root@doge:/etc/cron.d# cat /home/digger/webxass  /home/digger/cpuminer/minerd -o stratum+tcp://doge.pool.webxass.de:3333 -O <user>.<worker>:<worker_password> root@doge:/etc/cron.d#  root@doge:/etc/cron.d#  root@doge:/etc/cron.d# /home/digger/cpuminer/minerd -o stratum+tcp://doge.pool.webxass.de:3333 -O <user>.<worker>:<worker_password> [2013-12-21 11:57:09] 1 miner threads started, using 'scrypt' algorithm. [2013-12-21 11:57:09] Starting Stratum on stratum+tcp://doge.pool.webxass.de:3333 [2013-12-21 11:57:09] Stratum detected new block [2013-12-21 11:57:11] thread 0: 4104 hashes, 6.24 khash/s [2013-12-21 11:57:43] Stratum detected new block [2013-12-21 11:57:43] thread 0: 211512 hashes, 6.46 khash/s [2013-12-21 11:58:43] thread 0: 387384 hashes, 6.47 khash/s [2013-12-21 11:58:48] Stratum detected new block [2013-12-21 11:58:48] thread 0: 32964 hashes, 6.47 khash/s ^C root@doge:/etc/cron.d#  root@doge:/etc/cron.d#  root@doge:/etc/cron.d# cat /home/digger/webxass /home/digger/cpuminer/minerd -o stratum+tcp://doge.pool.webxass.de:3333 -O <user>.<worker>:<worker_password> root@doge:/etc/cron.d#  root@doge:/etc/cron.d# su digger digger@doge:/etc/cron.d$  digger@doge:/etc/cron.d$ /home/digger/webxass  [2013-12-21 11:59:51] 1 miner threads started, using 'scrypt' algorithm. [2013-12-21 11:59:51] Starting Stratum on stratum+tcp://doge.pool.webxass.de:3333 [2013-12-21 11:59:51] Stratum detected new block ^Cdigger@doge:/etc/cron.d$    There's some sort of syntax error, but I don't know what it is.    I really don't understand the "bad username" error, digger is a valid user.  Which username is bad?  The digger username in the system?


On finding enough rationals (countable) to fill the uncountable number of intervals between the irrationals.

Given the irrationals are an uncountable infinity, (on, say, (0,1),) the intervals between the irrationals which partition the interval (0,1) must also be an uncountable infinity. However, on each interval between any two irrationals, we know that there lies at least a countable infinity of rationals.  Since there are an uncountable number of intervals, each with at least a countable infinity of rationals on them, how can there only be only a countable infinity of rationals?


I use pixel inspector in Arcgis  to find cell values. this is very helpful tool in arcgis. I wanted to know if there is such a tool in Qgis which can help me to find the cell values(Except the identify tool).


If time stops at the speed of light, how do photons vibrate in waves

I understand photons travel at light speed because they have no mass therefore they travel at the fastest possible speed, and at the speed of light time stops. If time is frozen at light speed how do photons vibrate/osculate/have wavelengths? Are photons not effected by time dilation, or is the wave frequency just a symbolic representation of how closely packed together the electric and magnetic fields are to each other?


Determine the degree of the extension $\mathbb{Q}(\sqrt{3 + 2\sqrt{2}})$.

The following is from a set of exercises and solutions.     Determine the degree of the extension $\mathbb{Q}(\sqrt{3 + 2\sqrt{2}})$ over $\mathbb Q$.   The solution says that the degree is $2$ since $\mathbb{Q}(\sqrt{2}) = \mathbb{Q}(\sqrt{3 + 2\sqrt{2}})$. I understand that the LHS is a subset of the RHS since $$  \sqrt{2} = \frac{(\sqrt{3 + 2\sqrt{2}})^2 - 3}{2}. $$  How can the RHS be a subset of the LHS?  In other words, how can $\sqrt{3 + 2\sqrt{2}}$ be in $\mathbb{Q}(\sqrt{2})$?   The author of the solution mentioned that $(1 + \sqrt{2})^2 = 3 + 2\sqrt{2}$ but I do not see how this helps.


A closed ball in a metric space is closed

Prove that any closed ball in a metric space is closed.   (Note that this is not a duplicate as this is a proof verification question and have a different proof, in my opinion, as compared to other proofs on this site)  My Attempted Proof:   Let $(X, d)$ be a metric space. Pick a closed ball $\Phi = \overline{B(x, r)} = \{y \in X \ | \ d(x, y) \leq r\}$. Note that at this moment in time $\overline{B(x, r)}$ is just a notation, we don't know if $\Phi$ is actually closed.  We now show that $\Phi$ is closed. To do this we show that $X \setminus \Phi$ is open. Observe that $X \setminus \Phi = \{y \in X \ | \ d(x, y) > r\}$. Pick $y \in X \setminus \Phi$. For this $y$ we have $d(x, y) > r$ which implies that $d(x, y) = r + \epsilon$ for some $\epsilon > 0$.   We claim that $B(y, \epsilon) \subseteq X \setminus \Phi$. To prove this claim, pick $z \in B(y, \epsilon)$. We now show that $z \in X \setminus \Phi$ by showing that $d(x, z) > r$. To that end observe that the triangle inequality gives us   \begin{align*}    & d(x, y) \leq d(x, z) + d(z, y) \\    & \implies \epsilon + r \leq d(x, z) + d(y, z) \\   & \implies \epsilon + r < d(x, z) + \epsilon \ \ \ \ \ \  \ \ \  \text{since $d(y, z) < \epsilon$} \\   & \implies r < d(x, z)   \end{align*}  as desired. Hence $z \in X \setminus \Phi$ and we have $B(y, \epsilon) \subseteq X \setminus \Phi$, and since $y$ was arbitrary we have that $X \setminus \Phi$ is an open set in $(X, d)$ and thus $\Phi$ is a closed set. $\square$    Is this a rigorous and satisfactory proof? Can it be improved in any way?


How to make a python code wait in blender?

I want blender to execute the part of my code, then wait for about 30 sec and execute the rest code. Is it possible? I want something like setTimeout in js if not, then how do I execute one script, and then another one by one via bash or python script?


delete duplication in a table and retain one

The main table is Table2 and I want to delete duplication RollID in Table1 but retaining 1 like the example below 6456 (Note: Primary Keys Table ID's are auto-incremental)  Table 1 (child table)  Table1_ID   RollID  1          6456   2          6456   3          6459    Table2 (Parent)  Table2_ID    RollID  1            6456   2            6459    How can I attain this scenario.. Your helping hand is highly appreciated...


Determine all the connected subsets of $\mathbb{Z}.$?  I thinks $\mathbb{N} $ will  be the all connected subset of $\mathbb{Z}.$  I'm right or wrong


I use Manual Focus to take pictures. I find picture to be of high quality(clarity) when i see the picture in the camera screen. But if i import the picture to my PC it becomes blurry and not that great in details. I have tried with L, RAW+L, L (Day and Night). Still the image when viewed in bigger screen looks blurry. I use Canon 700D (18-55 IS II and 55-250 IS II, AP:3.5 - 5.8) to take pictures. I am new to photography. Seeking some inputs from peers over here with regard to take better quality pictures.  Sample Picture:


phpMyAdmin - How to save mp3 files in database?

I am programming a website where I need to store mp3 files in a database. I am using phpMyAdmin and mySQL for my database and am programming the website using html/php/css/javascript.   After doing some research, I have found that a good method for doing this is to not to store the actual mp3 file in the database, but to store the path to the file and to store the mp3 file on the "filesystem".   I am new to web development, so what do people mean by "filesystem" and how would I save/retrieve an mp3 file to the "filesystem"?


So I'm still having trouble with this hair, but now I've run into another problem.  I didn't have any particular texture for the shapes on Blender and after watching a tutorial instead of just winging it and googling things, I turned it to red and turned on AO.  I originally had three pieces. The middle, and then the side in which I copied and mirrored. Then I joined them all, and it looked kind of clunky but I didn't see this weirdness until I put on the red texture thing.   Also please ignore the ear I know it's off, I'm trying to fix it but it's not on my priority list rn       when i take the matcap off


Say I've read html input into a string and then do:      content = content.replaceAll("<[^>]*[^\\s>][^>]*>", "");   Right now, this removes all html tags except those that look like:      <>   and      < (any amount of white space) >   but I'd also like to include tags that contain non-printable characters to that list of exceptions. Is there anyway I can modify the replaceAll regular experssion to accomplish that?  If so, how?  Thanks for any input/suggestions.


Bringing laptop without battery to the US

I own a laptop but without the battery (since I never used it, I gave it away). Since it is required to have a charged battery on some flights to the US, I was wondering how to bring my laptop to the US. Who should I contact to get an exemption?


How can I debug white screen when running install script?

I'm doing a fresh install of drupal7 on Ubuntu following .  When I get to the point of  (by pointing the browser at localhost/drupal7/install.php) it just gives a blank screen.  Most questions/help about the Drupal blank screen relate to site setup but as this is a new install, I haven't created any sites yet so am unable to figure out what to do.  Does anyone know how to debug or move past this issue?


I've created a class called Human that works properly, it takes 2 arguments, age and name, to create a human.  To create a Human with command line arguments, I want to write      java Filename -H "Anna" 25   And it should create a Human with thatname="Anna", and thatage=25, where 25 is an int.  The code I've written is creating a list called Argument, and iterating through it to find -H. I need to do this because I'm going to be using this to create different classes later. I just need help with the syntax on the lines where I've written thename=, and theage=, because I don't know how to get the next item in list, and next-next item in list.  public static void main(String[] args) {     ArrayList<String> Argument = new ArrayList<String>();             for (String item: args) {         Argument.add(item);              }      for (String item2: Argument) {         if (item2 == "-H") {             thatname = Argument.get(item2+1)             thatage = Argument.get(item2+2)             Human person = new Human(thatname,thatage);             System.out.println(person);         }


What is the difference between GARCH and ARMA?

I am confused. I don't understand the difference a ARMA and a GARCH process.. to me there are the same no ?  Here is the (G)ARCH(p, q) process  $$\sigma_t^2 =      \underbrace{     \underbrace{      \alpha_0       + \sum_{i=1}^q \alpha_ir_{t-i}^2}     _{ARCH}        + \sum_{i=1}^p\beta_i\sigma_{t-i}^2}     _{GARCH}$$  And here is the ARMA($p, q$):  $$ X_t = c + \varepsilon_t +  \sum_{i=1}^p \varphi_i X_{t-i} + \sum_{i=1}^q \theta_i \varepsilon_{t-i}.\,$$  Is the ARMA simply an extension of the GARCH, GARCH being used only for returns and with the assumption $r = \sigma\varepsilon$ where $\varepsilon$ follows a strong white process?


Mac iBook G4 crashed, how to make bootable Ubuntu for Mac

I have a Mac iBook G4, which is not booting at all and it requires 'OS X Recovery CD', which i do not have. So I wanted to install Ubuntu on, which I already use on another system.   A step by step guide, for burning the .iso image, or a bootable USB version guide for Ubuntu 13.10 for my iBook is highly appreciated.


Indirect Speech: they said that that change.... is correct?

I want to transform this sentence     "This change is good" - Teachers   to indirect speech:     The teachers said that that change was good.   Is this sentences correct? Can I use double that?


Prove by Contradiction: if $4\mid a^2 + b^2$, then $a$ and $b$ are not both odd

Prove by Contradiction     Suppose $a, b \in Z$. If $4|(a^2 + b^2)$, then $a$ and $b$ are not both odd.   So the contradiction: Assume $4|(a^2 + b^2)$, where $a$ and $b$ are both odd.  Then $a=2k+1$, $b=2l +1$  And then I substitute it into the equation and the result is something like this? $4|4(k^2 + k +l^2 + l) + 2$  What do I do next to prove this?


I am kind of new to blender and I was working on a player model. I ran into a problem where I dont have faces on the arm pit. I dont know how to fill them in... I am really sorry if this is a dumb question.


If $ \operatorname{Tr}(M^k) = \operatorname{Tr}(N^k)\;\forall 1\leq k \leq n$, then how do we show the $M$ and $N$ have the same eigenvalues?

Let $M,N$ be $n \times n$ square matrices over an algebraically closed field with the properties that the trace of both matrices coincides along with all powers of the matrix. More specifically, suppose that $\mathrm{Tr}(M^k) = \mathrm{Tr}(N^k)$ for all $1\leq k \leq n$. The following questions about eigenvalues is then natural and I was thinking it would be an application of Cayley-Hamilton but I am having trouble writing out a proof.  How do we show that $M$ and $N$ have the same eigenvalues?  Added (because this question is now target of many duplicates, it should state its hypotheses properly). Assume that all the mentioned values of $k$ are nonzero in the field considered; in other words either the field is of characteristic $0$, or else its prime characteristic $p$ satisfies $p>n$.


How to check when a process stopped running?

I'm trying to figure out when a command I entered stopped executing, for example  sudo apt-get update   I want information like:   started execution at : 12:00 finished execution at : 12:15


prove that if $1 \le m \le n$ then $\left(1+\frac1n\right)^m < 1+\frac mn + \left(\frac mn\right)^2$

We know that $\dfrac1n>0$, $\dfrac1n<\dfrac mn<1$, $\left(\dfrac1n+1\right)^m < \left(\dfrac mn+1\right)^m$, so we have to prove that $\left(\dfrac mn+1\right)^m<\dfrac mn+1+\left(\dfrac mn\right)^2$.  I tried using Newton's binomial expression of $\left(\dfrac mn+1\right)^m$ and calculating the difference, but I didn't get there.


Careers tag search should only search tags

This URL specifies a tag search for Go jobs ("tag/go"):    However most of the results aren't tagged "go." (Tags are indicated by blue rectangles.)  Instead, results include jobs that merely refer to the keyword in the body of the post. A tag search should only display careers that are tagged with the search term.  Note that this is true of any term, not just "go," which is admittedly more generic. Searches for "ruby" or "python," for example, reveal the same issue--results that aren't tagged with "ruby" or "python."  A tag search should only search tags, exactly as implied by the URL.


How to write two functions, one on top of the other


List all directories that do NOT have a file with a given file name inside

How would I go into listing all directories that do not have a file with a given file name inside? e.g. given this tree  /   /a      README      file001      file002   /b      README      file001   /c      file003   I want to list the directories that do not have a file named README, in this case it would be directory /c. How would I do that? I can't think of any syntax using e.g. find.


That might be a silly question, but I'm staring at this code for a while and can't think of what's wrong. On compiling:  #include <string> #include <map>  template <typename T> struct my_string_map {     typedef std::map<std::string, T> type; }; template <typename T> bool add_to_string_map(my_string_map<T>::type map,         std::string str, T x) {     if (map.find(str) != map.end())          return false;     map[str] = x;     return true; }   I get:  foo.cpp:8: error: template declaration of ‘bool add_to_string_map’ foo.cpp:8: error: expected ‘)’ before ‘map’ foo.cpp:8: error: expected primary-expression before ‘str’ foo.cpp:8: error: expected primary-expression before ‘x’   (Definition of my_string_map class was taken from another thread of this forum)  When i specialize what template type I'm using, like in   bool add_to_string_int_map(my_string_map<int>::type map,         std::string str, int x) {     if (map.find(str) != map.end())          return false;     map[str] = x;     return true; }   everything works fine. Why it's not working and/or how to get it working?  Thanks in advance for your help


Redirect console output to textbox in separate program

I'm developing an Windows Forms application that requires me to call a separate program to perform a task.  The program is a console application and I need to redirect standard output from the console to a TextBox in my program.    I have no problem executing the program from my application, but I don't know how to redirect the output to my application.  I need to capture output while the program is running using events.    The console program isn't meant to stop running until my application stops and the text changes constantly at random intervals.  What I'm attempting to do is simply hook output from the console to trigger an event handler which can then be used to update the TextBox.  I am using C# to code the program and using the .NET framework for development.  The original application is not a .NET program.  EDIT: Here's example code of what I'm trying to do.  In my final app, I'll replace Console.WriteLine with code to update the TextBox.  I tried to set a breakpoint in my event handler, and it isn't even reached.      void Method()     {         var p = new Process();         var path = @"C:\ConsoleApp.exe";          p.StartInfo.FileName = path;         p.StartInfo.UseShellExecute = false;         p.OutputDataReceived += p_OutputDataReceived;          p.Start();     }      static void p_OutputDataReceived(object sender, DataReceivedEventArgs e)     {         Console.WriteLine(">>> {0}", e.Data);     }


Macbook Pro Retina 13,3" tingling/buzzing sensation

Okay, so YESTERDAY i bought my (super very wow expensive) Macbook Pro Retina 13,3". Huge investment for me. Yesterday night i tried charging i for the first time, and it started tingling against the palms of my hands whenever i like moved it across the under-keyboard area. I've read a lot about it, and i've read that it's normal, and that i have to use a three plug charger - the problem is that in Denmark we dont use three plug chargers, so i really dont know what to do! I just can't believe that i've saved so many money for so long, and that I experience problems after less than 12 hours.. ugh. Hope you can help me.


$G_1$ is graph on the set of vertices $\{1,2,3,4,5,6,7,8\}$, $G_1$ vertice chromatic number is 5.  $G_2$ is graph on the set of vertices $\{7,8,9,10,11,12,13,14,15,17,18,19,20\}$, $G_2$ vertice chromatic number is 7.  we know $G_1$ and $G_2$ have an edge between vertice 7 and vertice 8. (we already used 2 differnt colors on them both).  $G$ is graph on the set of vertices $\{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20\}$, that it's set of edges is the union of the edges set of $G_1$ with the edges set of $G_2$.  the vertice chromatic number of $G$ is: 5 / 7 / 12 / we can't know without further information  prove the answer.  As I understand, no vertice of $G_1$ can be connected to a vertice of $G_2$, except vertices 7 and 8, if we use 7 different colors on $G_2$, with vertice 7 and vertice 8 counted as 2 of them, and we use 5 colors on $G_1$ (with vertice 7 and vertice 8, counted as the same colors we used to color $G_2$ ) $G$ must have a vertice chromatic number of 7.  too simple in my opinion, I'm already waiting for my mistake.


Subsubsequence converges $\implies$ sequence converges

Prove that if $\left\{ x_n \right\}$ is an infinite sequence of real numbers, $x \in \mathbb{R}$, and every subsequence $\left\{ x_{n_k} \right\}$ has a subsequence $\left\{ x_{n_{k_j}} \right\}$ with $x_{n_{k_j}} \rightarrow x$, then $x_n \rightarrow x$.   I know that if every subsequence of a sequence converges to the same number, then the sequence converges to that same number. But I don't know if the same can be applied to subsubsequences. So for this problem, can I safely state that because $x_{n_{k_j}} \rightarrow x$, it is also true that $x_{n_k} \rightarrow x$? If this is true, then does that mean every subsequence $\left\{ x_{n_k} \right\}$ also converges to $x$?


I was trying to load pages changing the last value of the url. It seems to work only with the last number (j=19). I don't undestand why it seems to skip the other pages.  <!DOCTYPE html> <html> <head> <script> function newIP(n) {     window.location.replace("@@@@@:"+n)  } </script> </head> <body>  <script> var j; for (j=0; j<20; j++) {     window.setInterval(newIP(j), 1000); } </script> </body> </html>


I'm trying to make a hangman game, but I'm getting hung up on things like arrays

import java.util.Scanner; import java.util.ArrayList;  public class hangman {      public static void ttt(String inputWord) {         int wordLength = inputWord.length();         String blanks = "";         for (int i = 0; i < wordLength; i++) {             blanks = blanks.concat("_ ");         }         // System.out.print(wordLength);         System.out.println(blanks);         int points = 0;         int counter = 0;         ArrayList<String> usedChars = new ArrayList<String>();         while (points < wordLength) {             Scanner reader = new Scanner(System.in);             System.out.println("Guess: ");             String guess = reader.next();             // int checker = 0;             // for(int k = 0; k < usedChars.size(); k++) {             // if(usedChars.get(k) != guess) {             // checker = checker + 1;             // }             // else {}             // }             // if(checker == usedChars.size()) {             for (int i = 0; i < wordLength; i++) {                 if (guess == inputWord.substring(i, i + 1)) {                     points = points + 1;                     usedChars.add(guess);                     System.out.println("hit"); // this is me trying to see if                                                // this part is working                 } else {                 }              }             System.out.println("Used letters: " + usedChars);             // }             // else {             // System.out.print("Sorry, that letter has already been used");             // }             counter = counter + 1;             if (counter == 5) {                 points = wordLength;             }          }          System.out.println("Game over");     }      public static void main(String[] args) {         ttt("to");      }  }   Don't worry about the commented out code, that's just me going over the top trying to prevent duplicate guesses, but it's more important that I get the rest of the code to work first.  Anyway, the only part of my code that seems to be working is the counter part. You can try it yourself, but it seems like all it does it take 5 guesses (5 lives, kind of random) and print game over.  edit: in hindsight i need to revisit that counter part, because it should only increase for incorrect guesses  The first thing I noticed was that my array isn't working correctly. It's not .add()'ing like I ask it to add my guesses. (Source: )  Then, the more serious problem of the code not even being able to record correct guesses :/  I'm starting to code in my school's java class and decided to try this on my own for fun, any help would be greatly appreciated! :P


Basic job control: stop a job, add a job onto the stack, and `fg`

Job control is probably my favorite thing about Linux. I find myself, often, starting a computationally demanding process that basically renders a computer unusable for up to days at a time, and being thankful that there is always CTRL-Z and fg, in case I need to use that particular computer during that particular time period.  Sometimes, however, I want to insert a job onto the job stack. I've never figured out how to do that.  I'm using bash.   It would probably look something like:  $ ./reallybigjob ^Z [1]+  Stopped                 reallybigjob $ (stuff I don't know) && ./otherbigjob $ fg


Can a gerund be used to start a question title?

For the sake of using less characters in a title I often change a question like:     How do I learn to ride a bike?   to:     Learning to ride a bike?   I know these two constructs are not identical in meaning but the intention is to use one or other as a title summarizing a Stack Exchange question about a problem encountered when learning to ride a bike.   Are both grammatically correct i.e. can a question begin with a gerund?


Smart way to Integrate $\int \dfrac{dx}{1+x^4}$

I know abt that straightforward lengthy way.  anyone knows a smarter way


Why did the Doctor think he was going to die in "The Time of the Doctor" even though he saw Capaldi in "The Day of the Doctor"?

The 13th Doctor, Capaldi, showed up in "The Day of the Doctor" when the Doctors froze Gallifrey.   So, if the 12th Doctor saw him back then, how come he thought he was the last Doctor at the episode "The Time of the Doctor"? Could he have just forgotten?


I've been wondering whether light has mass. Yet given the wave-particle duality of light, the statement seems to be affirmative. With that, how to calculate it?


I got myself an irritating Javascript virus

so I got a javascipt virus in my Laptop:  effects:   *can't open regedit.exe and resource monitor, they just show for maybe 0.5     seconds and exit(they just blink), the same thing happens when I try to     install Anti-Virus Programs, I tried to download AVAST and AVG but they just     blink, and about malwarebytes, when I try to open it it doesn't show anything     but sometimes a window appears and gives me two options either to look online     for solution(which doesn't help me at all) and to exit the program.    please take a look at the pics. Here, in the first picture is the task manager, the one with the "Microsoft Windows Based Script Host" are the javascript executables(in the next picture):    in the PIC2 is the file location of the said virus I suspect in the task manager(with a hidden attribute of course):    and I tried to right click>>edit on the "gcfaucx.js" file on pic2 and I think I met the source code but unfortunately it's too many words and I don't know if it's legit to post it here, and if you have any question please do ask, I'll need it,


Since photons move at $c$, do they experience time or distance?  If they don't, doesn't this explain action at a distance?  From the point of view of the photons, there is no time, so the action at a distance must happen instantly.  It only seems weird from our point of view.


if no expanded-name, how to get file type(image/audio or video) by java?  I want to write a function like this:  String getFileType(String filePath){    // TODO:...    return type; }


two column document so in the first i have text and in the second pictures

I want to make a two column document such as in the first column there is text and in the second column pictures with examples for the text. How can i do that?


Parameterize line to correspond to t values

Parameterize the line through P=(−3,−1) and Q=(0,7) so that the points P and Q correspond to the parameter values t=13 and 16.  I have found the direction vector <3,8> and then have plugged in to find the following:  r=<-3,-1> +t<3,8>  x=3t-3 y=8t-1  I am lost as to the next steps to scale this appropriately to come up with the correct equation.


Now that the close/flag reasons have been changed, we can directly flag a question for migration to a different site on the StackExchange network.  However, there's only 5 options, with an important one missing:  , the site for software development at a more conceptual level.  Was this an intentional omission?  I often see questions on here that would do better over there, like this one just now:    (I'd flagged it as "Needs  moderator attention", then explained that Programmers.SE would be a better fit.  Then I realized I should ask here.)


Solving a pair of quadratic equations for two unknowns efficiently

I have a pair of quadratic equations in the form  $ax^2 + bx + cy^2 + dy + e = 0$  $fx^2 + gx + hy^2 + ky + l = 0$  and there should be a solution in the range $-2 \leq x,y \leq 2$ which I need to find programmatically.  I can eliminate one variable by squaring to get a quartic equation which I could solve numerically and substitute back, but I'm not sure about numeric stability and spurious roots.  Is there a better way of solving this?  Edit: This question  has answers with comments "In order to solve this degree 4 equation you need either some luck, or some patience " and "How would one programatically find the lines that constitute a degenerate conic?". That does not seem to demonstrate a better/simpler solution.


In thermodynamics, how does the triple point occur?

A triple point is where a matter coexist in its three physical states . But how is it possible and what happens at the microscopic scale?


Really awful 1970s movie about mercury dumped in a lake that caused monsters to attack

Sometime in the 1970s (I think) I saw a really awful film set in a small town by a lake. The film opened with some people camping out in the woods. One of them was zipped up in a sleeping bag. Something (as yet unidentified) moved in between the sleeping camper and the camera, and we heard a "crunch." When the creature moved off, we saw that it had bitten the head off the camper, causing a fountain of blood to spout of of the neck. Far from being shocking or gory, it was so badly done as to be laughable.  The main story was that these huge and nasty mutated creatures were coming out of the lake and eating people. A local industrial company was under suspicion for poisoning the lake, but repeated water tests showed it to be clean.  In the end, someone had the idea of testing the water at the bottom of the lake, which revealed it to be heavily poisoned with mercury. As mercury is much heavier than water, it had sunk, so the previous tests (done from a small row boat) had missed it as they only sampled the water at the surface.  They got it all sorted out eventually, and the bad guys ended up in prison.  After the credits had rolled, and you thought it was all over, another monster reared up in front of the camera and roared. I think we were supposed to go "Oh no, it's not all over!" However, the few people stupid enough not to have left by now laughed at the ridiculous sight and left, shaking their heads wondering why they had bothered!  I have a morbid fascination to see it again. Anyone have any idea what it was called?


is $\mathbb{Z}[\sqrt{-11}]$ factorial / UFD?

I am trying to figure out whether $\mathbb{Z}[\sqrt{-11}]$ is a unique factorization domain. A hint provided is to "Consider for example the irreducibility of 2 and the primality of the ideal (2)".  I assume that we will have to use the fact that in UFD's, irreducible elements generate (nonzero) prime ideals, and that the converse holds too.  So I first want to check whether 2 is irreducible and I set : $2=(a+b\sqrt{-11})(c+d\sqrt{-11})=(ac-11bd)+(ad+bc)\sqrt{-11}$ which implies that: $2=ac-11bd$ and $0=ad+bc$.   From there, I don't exactly see how to proceed in a smarter way than just trying out numbers for a,b,c and d.  Then I want to check whether the ideal generated by 2 is prime: An element in $(2)$ is of the form $2(x+y\sqrt{-11})$. Let two elements in our ring be such that their product is in $(2)$. We want to show that at least one of these elements must be in $(2)$ for the ideal to be prime.  $(p+q\sqrt{-11})(r+s\sqrt{-11})=2(x+y\sqrt{-11})$ implies that : $pr-11sq=2x \:\text{and}\: ps+qr=2y$.  Again, I don't see how to proceed from there. I'd be grateful for some insight on this!


How do I edit name and logo for boot menu of Windows 10 EFI drive?

I have a new Windows 10 EFi formatted drive, and I am wondering what is the proper way to customize the boot menu logo and the name? For example, changing the orange drive logo to a picture, or changing the boot menu name "EFI Boot" to "My Drive".  My Mac is running macOS Catalina.


There is no way to delete an answer that you have posted. I find it all too easy to accidentally post an answer instead of a comment, (maybe some better posting differentiation is needed?) and it's not possible to delete the mistakenly created answer ater copying the content to a comment.  On the web I don't need to "vote" to delete my own answers. This has nothing to do with allowing voting on deletion, but the direct (and immediate) deletion of my own answers to questions which doesn't require any voting of any form at all. I just press "delete" and it's deleted.


New possible bug in biblatex-chicago: how to make new error message go away

Ever since updating all packages on TeX Live Utility (on Mac OS) yesterday, including biblatex-chicago, I have been getting this non-critical error message/warning every time I run xelatex on a file using biblatex-chicago: Runaway argument? { /usr/local/texlive/2020/texmf-dist/tex/latex/biblatex-chicago/chicago-notes.cbx :6629: Paragraph ended before \blx@defformat@i was complete. <to be read again>                     \par  l.6629 \DeclareFieldFormat{annotation}{\par                                            \nobreak \vskip \bibitemsep #1} ?  /usr/local/texlive/2020/texmf-dist/tex/latex/biblatex-chicago/chicago-notes.cbx :6629: You can't use `macro parameter character #' in vertical mode. l.6629 ...ation}{\par\nobreak \vskip \bibitemsep #                                                   1} ?   /usr/local/texlive/2020/texmf-dist/tex/latex/biblatex-chicago/chicago-notes.cbx :6629: LaTeX Error: Missing \begin{document}.  Is this due to a bug? And if so, is there some way to fix it?


I am using the book class for my thesis. However, the default alignment is very strange as shown in the following sample.    As it shows, extra space was added between lines so that the content is filled over the whole page. What I need is to fill the page normally wihout the extra space?


Wireless LAN not working on Lenovo Ideapad 330

I have installed Ubuntu 18.04 in Lenovo Ideapad 330. After installation Wireless LAN adapter is not working. Output of lspci -knn | grep -i Net -A2:  03:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8821CE 802.11ac PCIe Wireless Network Adapter [10ec:c821] Subsystem: Lenovo RTL8821CE 802.11ac PCIe Wireless Network Adapter [17aa:c024]


Is there a way to install Ubuntu 14.04 LTS without the software, just command line? (desktop version, not server)  Thank you.


Relating torque and time rate of change of angular moment when an object isn't rotating about its center of mass

My book "Fundamentals of Physics" by Halliday, Resnick, Walker says:  The net external torque acting on a system of particles is equal to the time rate of change of the system's total angular momentum  Then it says:  Caution: Torques and the system's angular momentum must be measured relative to the same origin. If the center of mass of system is not accelerating relative to an inertial frame, that origin can be any point. However if it is accelerating then it (center of mass) must be the origin. For example, consider a wheel as the system of particles. If it is rotating about an axis that is fixed relative to the ground, then the origin for applying the formula (net external torque acting on a system =time rate of change of the system's total angular momentum) can be any point that is stationary relative to the ground. However, if it is rotating about an axis that is accelerating (such as when the wheel rolls down a ramp), then the origin can be only its center of mass  My question: Suppose a uniform circular disk is rotating about an axis Q that is x meters away from center of mass. It is also accelerating (linear as well as rotational) just like that wheel rolling down the ramp given in example. Can't we apply this formula about axis Q? According to the text given in book "when the system is accelerating then center of mass must be the origin". Here in my question The center of mass is rotating, so how can we use it as origin?


How can I extract Chinese symbols from text

I am unable to post Chinese text symbols here but basically I just want to remove all the lines that do not contain at least one Chinese symbol.    How can I extract that so it looks like


How to input different classes and put it to the common array in Java?

I have a task: Create abstract class Product, then create two inheritant abstract classes MilkProduct and MeatProduct and their inheritants (Milk, Meat, Kefir, Sausage) and output them in descending order by their codes.  public abstract class Product { protected String name; protected int code;  public Product() {} public Product(String name, int code) {     this.name = name;     this.code = code; }  public abstract void input(); public String toString() {     return "{Name : " + name             + ";" + "Code: "             + code + "}"; }  public String getName() {     return name; }  public void setName(String name) {     this.name = name; }  public int getCode() {     return code; }  public void setCode(int code) {     this.code = code; } }   import java.util.Arrays; import java.util.Scanner; public class Program { public static void main(String[] args) {     Product[] arr = new Product[10];     Scanner in = new Scanner(System.in);      for (int i=0;i<arr.length;i++) {         arr[i].input();         if (arr[i].name == "Milk") {             arr[i] = new Milk(arr[i].name, arr[i].code);         }         else if (arr[i].name == "Kolbasa") {             arr[i] = new Kolbasa(arr[i].name, arr[i].code);         }         else if (arr[i].name == "Meat") {             arr[i] = new Meat(arr[i].name, arr[i].code);         }         else if (arr[i].name == "Kefir") {             arr[i] = new Kefir(arr[i].name, arr[i].code);         }     }      Arrays.sort(arr);     for (Product e: arr) {         e.toString();     } } }   and i got an error      Exception in thread "main" java.lang.NullPointerException     at   HWvirtual.Program.main(Program.java:11)


if $\operatorname{Dim}(A)=0$, then every prime ideal is maximal

Given a ring $A$, By the chain of prime ideals of $A$, we mean a sequence of prime ideals of $A$ such that $P_0 \subsetneq P_1 \dots \subsetneq P_{n-1}\subsetneq P_n$. Further this chain has a length $n$.  Define the dimension of a ring $A$ by $\operatorname{Dim}(A)$ to the supremum the lengths of all chains of prime ideals of $A$.     Show that if $\operatorname{Dim}(A)=0$ then every prime ideal is maximal.   Attempt: Suppose that there exists a prime ideal $X$ which is not maximal, then there exists an ideal $Y\subsetneq A$ properly containing $X$. Now my aim is to show that there exist a sequence of prime ideals $P_0 \subsetneq P_1 \dots \subsetneq P_{n-1}\subsetneq P_n$ with $n \geq 1$. I am getting $Y$ as an ideal. I am not getting any prime ideal after that. How should I proceed from here?  Also I cannot use $0=\{0\}$ since $0$ is not a prime ideal.


When I start any Qt app, I get this message in the terminal, and the Qt app doesn't use the same theme as my Gtk apps:  QGtkStyle was unable to detect the current GTK+ theme.   How do I make QGtkStyle detect my current GTK+ theme?  It seems that LXDE is using a settings daemon, and there is no gtkrc-2.0 file in my home folder.


Changing keys appearing on the final pdf

My current state is        and I would like to change this appearance of cites with a single number to three characters juxtaposed with two numbers, each of which denotes authors and years of a paper, as follows:        I wonder how to do this, and any comment would be appreciated!


Prove that $2c^3+1$ is never a perfect cube for $c \in \mathbb{N}^*$

I am working on proving that the equation:  \begin{align} a^2-b^3 = 1 \end{align}  where $a$ and $b$ are positive integers has only one solution $(a,b) = (3,2)$.  The equation can be rewritten:  \begin{align} (a-1)(a+1) = b^3. \end{align} When $b$ is odd, for any prime factor $p$ of $b$, we have that $p$ divides $(a-1)(a+1)$. But $a-1$ and $a+1$ are coprime when $b$ is odd, hence $p$ divides either $a-1$ or $a+1$ but not both. It follows that both $a-1$ and $a+1$ must be perfect cubes. Since there are no pair of perfect cubes with difference 2, it follows that $b$ must be even.   In this case let $b = 2n$ and for ease of reading, let $a = m+1$. The equation can be rewritten: \begin{align} m(m+2) = 8n^3. \end{align} This implies that $m$ is even, i.e. $m=2k$. The equation becomes: \begin{align} k(k+1) = 2n^3. \end{align} Depending on wether $k$ or $k+1$ is even, we have: \begin{align} q(2q+1) = n^3 \end{align} when $k=2q$, and  \begin{align} (q+1)(2q+1) = n^3 \end{align} when $k=2q+1$.   When $k = 2q$, since $\text{gcd}(q,2q+1) = 1$, we have that $q$ and $2q+1$ must be perfect cubes using the same reasoning as above. I would like to conclude by proving that there is no positive integer $c$ such that $2c^3+1$ is a perfect cube, hence the question in the title.


I have 3 databases on Azure's cloud, all with domains names such as xxxxxxxx.database.windows.net.  Would it be a bad idea to create domain name aliases for all 3, things such as:  database.domain.com  staging.database.domain.com  test.database.domain.com  The only issue I could come up with was that there could be a security risk involved, easily guessable domain names for the databases, but I'm not sure if that's even a risk with Azure SQL databases?


Why am I getting shocked by a water heater?

Background:  I live in Metro Manila, Philippines where the electric distribution company, Meralco, delivers split-phase power to residential buildings. Our old (1980s) Meralco service drop consists only of 2 conductors, both phase conductors, and no neutral conductor. Phase-to-phase voltage is 240V, while phase-to-ground (measured with the help of an existing ground rod) is 120V.  We recently started the construction of a new house and wired it according to the Philippine Electrical Code (PEC). Based on my research, the PEC is very similar to the NEC. That said, the new house uses three-prong receptacles: 2 for the phases and one for ground. The grounding conductor is connected to a ground rod.  Since Meralco still hasn't energized the new house, it is temporarily connected to the old two-wire service drop, leaving the grounding conductor connected to the ground rod only (i.e. no connection to the load-side neutral yet).  Problem:  The heater in question is a Panasonic Shower Heater DH-3JL2P (rated at 3.5 kW). Its terminals are labeled Line (L), Neutral (N), and Ground (G). When I tested this heater initially, I had no idea that Meralco's supply is split-phase, not single phase. So I just operated it under the assumption that the line and neutral conductors are connected correctly at the receptacle (which actually doesn't matter now knowing that the supply is split-phase, i.e. both are line conductors, there's no neutral conductor).  Upon testing, the heater functioned properly as far as heating the water is concerned. However, I felt a significant electric shock when I touched the shower head where the heated water was coming from.  What could cause this shock to happen? I have a couple of ideas on why this happened, but can't really say for sure:   Grounding conductor is disconnected to the load-size neutral (of the transformer). Heater is expecting a single-phase supply, not split-phase.   I can post a picture of the heater internals later.


Assistant professor vs lecturer in the UK

I have been looking at various graduate programs in the UK, and noticed a lot of people under the title "lecturer" taking incoming PhD students. I've completed some graduate studies on a master's level in the United States. Would doing a PhD under the supervision of a "lecturer" be different than doing one under the supervision of a professor? I read online that in the UK, "lecturer" is analogous with "assistant professor". Can someone explain this to me?


How many significant figures should one give in stating an experimental uncertainty?

How many significant figures should one give in stating a experimental uncertainty? For this purpose I found three rules:      Experimental uncertainties should be always stated to 1 significant figure.   For example: $3.45 \pm 0.015$ should be $3.45 \pm 0.02$ [].    The number of significant figures in the experimental uncertainty is limited to one or (if the uncertainty starts with a one, e.g., ± 0.15) to two significant figures.   For example:  $3.45 \pm 0.015$ should be $3.45 \pm 0.015$ [].    One significant figure should be used to report the uncertainty or occasionally two, especially if the second figure is a five.   For example: $3.45 \pm 0.035$ should be $3.45 \pm 0.035$ [].


Delete a folder that does not match a pattern

I have two folders, one that I know the name of, and one that I don't: ~/foobar-as9df7 # I know the name of this one ~/foobar-7fq92h # I don't know the name of that one  How can I delete the folder that starts with foobar- and is NOT ~/foobar-as9df7, and that I don't know the name of? Said differently, I want to rm -rf ~/foobar-as9df7 except that I don't know it's called foobar-as9df7, I only know its name starts with foobar- and it's not foobar-as9df7. I've tried doing: find foobar-* ! -name "foobar-as9df7"  -exec rm -rf {} \;  which works but strangely this triggers a message saying: find: ‘foobar-7fq92h’: No such file or directory  -- EDIT the output of this command: find ~/ -type d -name 'foobar-*' ! -name 'foobar-as9df7' -exec echo .rm -r {} +  is as follows: .rm -r /home/ubuntu/foobar-7fq92h


What is the permutation of word "MISSISSIPPI"?

What is the total no. of permutations of the letters of the word MISSISSIPPI in which no four "I"s come together?   My try-:  $7!/4!\times 2! \times 8!/4!$  But not getting the right answer.  Please help


A group of even order must contain an odd number of elements of order 2.

I tried it using proof by contradiction:  Suppose that there are even number of elements of order $2$. Call them $x_1, ..., x_{2m}$, where $x_1,...,x_{2m} \neq e$. Then, consider the set $G=G \setminus \{e,x_1,...,x_n\}$. The size of $G'$ is odd since the size of $G$ is even.  Elements in G' does not have itself as an inverse, since $x^2=e \iff x=x^{-1}$.  Also, note that each elements in G' has a different inverses. (Suppose $a\neq b$, $\ a,b \in G'$, and $\exists c \in G'$ such that $ac=bc=e$. Then, $a=b=c^{-1}$ which is a contradiction.)  This shows that $|G'| =$ even which is a contradiction.    This seems complicated for no reason. Is this correct? and how do I make my proof neater?


How to stop smoke simulation from rising?

I have a smoke simulation. How do I get it to not float up?


If processes inherit the parent's environment, why do we need export?

I read  that the purpose of export in a shell is to make the variable available to sub-processes started from the shell.  However, I have also read  and  that "Processes inherit their environment from their parent (the process which started them)."  If this is the case, why do we need export? What am  I missing?  Are shell variables not part of the environment by default? What is the difference?


This is the log:     Caused by: java.lang.NullPointerException: Attempt to invoke interface   method 'void   com.google.android.youtube.player.YouTubePlayer.cueVideo(java.lang.String)'   on a null object reference   I don't know why it has this error?  public class StudyActivity extends YouTubeBaseActivity implements YouTubePlayer.OnInitializedListener {  YouTubePlayerView youTubePlayerView; YouTubePlayer player;  @Override protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_study);      youTubePlayerView.initialize(KEY.YOUTUBE_API_KEY,this);     player.cueVideo("GyrH6xiFiT0");  } @Override public void onInitializationSuccess(YouTubePlayer.Provider provider, YouTubePlayer youTubePlayer, boolean b) {     player = youTubePlayer; }  @Override public void onInitializationFailure(YouTubePlayer.Provider provider, YouTubeInitializationResult youTubeInitializationResult) {     Toast.makeText(this, "Error!", Toast.LENGTH_SHORT).show(); } }


If water is flowing from a larger subsection $A_1$ of a pipe into a smaller subsection $A_2$ (say, the radius halves), then Bernoulli's principle says that the pressure $P_{A_1} > P_{A_2}$, and $v_{A_1} < v_{A_2}$.  I understand why the velocity would be greater, but why is the pressure at $A_2$ less than at $A_1$? Thinking about it without considering Bernoulli's equation, I'd imagine that the pressure at $A_2$ should be greater due to the smaller area, but this isn't the case. Why not? Physically, what's happening so that the pressure decreases?


Beautiful Soup 4 not working with Python 3.4.0

I am using Ubuntu 14.04 64 bit Operating System .   I installed Beautiful Soup 4 using this command :  sudo apt-get install python-bs4   With Python 2.7.6 , I had no difficulty importing the bs4 module. But when I used Python 3.4.0 it showed me this error.  >>>import bs4 Traceback (most recent call last):   File "<stdin>", line 1, in <module> ImportError: No module named 'bs4'   I also tried to install it using pip.  sudo pip install beautifulsoup4   But again it didn't worked with Python 3.4.0.  Right now I have uninstalled pip and also uninstalled Beautiful Soup 4   sudo apt-get remove python-bs4 sudo apt-get remove python-pip   What should I do next to properly install Beautiful Soup 4 for both  Python 2.7.6 and Python 3.4.0 ??


Date module text between start and end date

I'm wondering if it's possible to change the "to"-text between a start date and an end date.  I'm only using years, for instance I want to change the following line: "1925 to 1928" To this line "1925 - 1928".  I'm using drupal views, and this specific information is presented in a grid system.  Where can I change this?


How to find the length of a character array in c which contains multiple characters of asci 0 value

I have a character pointer of hex values like as follows. a= {0x01, 0x02, 0x00, 0x03, 0x04, 0x05, 0x00}; I have to find the length of the above array. But strlen gives 2 and sizeof gives 4(char pointer size). How can I find the length? I receive the character array from a socket.


Why `sudo apt-get install XXXX` sometimes request confirmation, others not?

Just for curiosity, sometimes while installing software throught apt-get install software_name the terminal prompt me for a confirmation "type Yes or No", but not allways.  I dont mean the sudo password prompt, but the message "Will be downloaded and configrated XXX Kb, continue?" (or something similar)  Why?


I have one blender save file that is basically just a render scene where I bake renders of models so they all have the same lighting and orientation. Naturally i accumulate a lot of textures over time and wanted to know if there is an easy was to instantly remove all unused textures at once.  I know i can delete all materials with one click, but the textures stay behind. I also know how i can delete textures one by one, but that takes too long.  Is there even a way to effectively delete all textures that are not used at once? I'd even be happy if i could delete all textures, even if they were used.


Prove that $\prod\limits_{n= 2}^{\infty} \frac{n^{3}+ 1}{n^{3}- 1}= \frac{3}{2}$, which is a beautiful value!

Prove that $\prod\limits_{n= 2}^{\infty} \dfrac{n^{3}+ 1}{n^{3}- 1}= \dfrac{3}{2}$, which is a beautiful value ! A solution due to a p u as follow $$\begin{align} \prod\limits_{n= 2}^{\infty} \frac{n^{3}+ 1}{n^{3}- 1} & = \prod\limits_{n= 2}^{\infty}\frac{(n+ 1)(n+ \omega )(n+ \omega^{2})}{(n- 1)(n- \omega )(n- \omega^{2})}\\   & = \prod\limits_{n= 2}^{\infty} \frac{(n+ 1)(n- 1- \omega)(n- 1- \omega^{2})}{(n- 1)(n- \omega )(n- \omega^{2})}\,(\!1+ \omega+ \omega^{2}= 0\,used\!)\\   & = \lim_{n\rightarrow \infty} \frac{n(n+ 1)(1- \omega)(1- \omega^{2})}{1\cdot 2(n- \omega)(n- \omega^{2})}\\   & = \lim_{n\rightarrow \infty} \frac{3(1+ \frac{1}{n})}{2(1- \frac{\omega}{n})(1- \frac{\omega^{2}}{n})}\,\left (\!(1- \omega)(1- \omega^{2})= 1+ 1+ 1= 3\,used\!\right )\\   & = \frac{3}{2} \end{align}$$ I have a solution, and I'm looking forward to seeing a nicer one(s), thanks for your interests a lot !


How to reference static member variables from a struct within another class

I'm trying to define some static constant strings in C++ and reference them from different files.  Here's how I have the information set up this far:  structClass.h  namespace test {      typedef struct customstructure{           static const std::string stringA;       } customstructure; }   structClass.cpp  namespace test {      static const std::string customstructure::stringA = "This is String A"; }   Now I'm wondering how I would call this in a third file?  execute.cpp  void printStringA(){     printf("stringA is: %s", test::customstructure::stringA.c_str()); }   gives me a compile error that says:  undefined reference to 'test::customstructure::stringA'


Print resolution when Photoshop shows pixels per inch not dpi

I am about to send some sketches which I have scanned and and tidied up in Photoshop.  My scans were 300dpi at the scanner.  I've checked by docs and they all say 300 pixels per inch.  Here's an example:    I tend to work for web, so don't do print stuff.    Am I on the right track?  Are the files big enough for print?  Please excuse my novice-ness.  Thanks.


Is there a general term for minimum, median, maximum, mean, quartiles, etc

I'm looking to be able to say something more brief than "this tool collects the minimum, median, mean, maximum, and quartiles" of a distribution.


How to mask out features outside of the Coverage Layer for Atlas plugin?

Using the Atlas plugin for qGIS how do I set the coverage so that it will only highlight the feature(s) I want but still show the surrounding features as grayed out areas?  This would have been easy if I don't need to work with several thousand features.  I am not asking just how to mask neighboring features. I am asking how to to make Atlas dynamically mask neighboring features of the POI.  The idea is similar to this map .


I have multiple hostnames resolving to a single machine, e.g.:   build.mydomain.com www.mydomain.com jira.mydomain.com mydomain.com   Is it possible to setup apache in order to redirect requests to each different hostname?  e.g:   build.mydomain.com -> build.mydomain.com:8111, www.mydomain.com -> www.mydomain.com:8080 mydomain.com -> www.mydomain.com:8080   The DNS records are setup to all point to the same machine, i just want to redirect to the right port given the hostname.  Cheers,  Edit:  Machine is debian w/ Apache2  Edit2:  <VirtualHost *:80>     ServerName www.mydomain.com     ServerAlias mydomain.com     redirect 301 / http://www.mydomain.com:8080/ </VirtualHost>  <VirtualHost *:80>     ServerName build.mydomain.com     redirect 301 / http://build.mydomain.com:8111/ </VirtualHost>


Running "sudo apt-get update" returns connection errors

After installing Ubuntu 18.04 from the Windows store I open Bash and want to run sudo apt-get update, but this returns the following errors:  Err:1 http://security.ubuntu.com/ubuntu bionic-security InRelease   Connection failed [IP: 91.189.91.26 80] Err:2 http://archive.ubuntu.com/ubuntu bionic InRelease   Connection failed [IP: 91.189.88.162 80] Err:3 http://archive.ubuntu.com/ubuntu bionic-updates InRelease   Connection failed [IP: 91.189.88.161 80] Err:4 http://archive.ubuntu.com/ubuntu bionic-backports InRelease   Connection failed [IP: 91.189.88.162 80] Reading package lists... Done W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/bionic/InRelease  Connection failed [IP: 91.189.88.162 80] W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/bionic-updates/InRelease  Connection failed [IP: 91.189.88.161 80] W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/bionic-backports/InRelease  Connection failed [IP: 91.189.88.162 80] W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/bionic-security/InRelease  Connection failed [IP: 91.189.91.26 80] W: Some index files failed to download. They have been ignored, or old ones used instead.   When I open 91.189.91.26 in a browser, it shows the site without a problem.  Previously this worked without any problem, but I did a clean reinstall of Windows and now it doesn't work anymore. It seems some firewall or proxy issue, but I tried with the firewall disabled and I got the same result.  Any idea why this is happening? Maybe it is a 18.04 issue? If so, is it possible to return to 16.04 on Windows 10? Becasue I don't see a uninstall option.


A "fast" way for computing $\sum\limits_{n=1}^{100} n\times 2^n $

How to compute 'z', where $\displaystyle z = \sum_{n=1}^{100} n\times 2^n$ ?   The answer is of the form $99 \times 2^{101} + 2$, I need a fast approach as this problem is supposed to be solved under a minute.


How to simplify the understanding behind Hypothesis Testing?

Quote recently, I have trying to understand this confusing idea of Hypothesis testing. Although I am pretty much clear with the way it works, that is:  Choosing a test statistic Then choosing a Null Hypothesis (H0) & an alternative hypothesis (H1) Finding out the P-Value If the p-value is greater than the significance level (assuming 0.05 for this question), then accepting H0, otherwise rejecting it  But I am still highly confused with the last step. Let me throw some light on my confusion with 2 examples. The 1st example is to check whether a coin is biased towards heads or not. So, we design an experiment in which we flip the coin 5 times, and the number of heads we obtain is the test-statistic and the coin is unbiased is our Null Hypothesis. Now, let's say we flip the coin 5 times, and we obtain 5 heads. So, P(5 heads | The coin is unbiased) = 1/32 ~ 0.03 (< 0.05), and hence we reject H0. The intuition behind it is pretty simple as well since the probability of obtaining 5 heads in 5 tosses, from an unbiased coin is very less, hence we concluded that the coin is biased. Now, comes the 2nd example, which puts me into great confusion. In this example, we need to determine if the heights of students from 2 different classes C1 & C2 follow the same distribution or not. So, we choose the test statistic (X) as the difference between the means of the heights u1 & u2, and we choose the null hypothesis as there being no difference in the means. Now, let's say that we performed an experiment and found out X to be 10cm. Now, we try to determine the p-value, that is P(X >= 10cm | H0), and let's say we obtain it to be 0.01 (< 0.05), and hence we reject the null hypothesis. Now, here is my doubt, if the p-value mentioned above is very less, then shouldn't it mean that there is no difference in the heights of students of C1 and C2? In simple words, if the p-value is 0.01, then shouldn't it mean that it is very less probable that the difference in the means of C1 and C2 is big, i.e. no difference in the heights of C1 and C2 (exactly the same as our Null Hypothesis), but it happens to be completely opposite? P.S. - This is my first question on any discussion forums, so let me know if I am missing some information that I need to add. Thanks in advance :)


How to define a const class-member function that is inheriting without duplicated-code?

Im trying to define a class which (its minimal version) would look like this: class Base{     int i; public:     Base(int i_): i(i_){}     int& at(size_t index) {return i;}     const int& at(size_t index) const {return i;} };  (Yes. It has an index because the class that i really want to create always need it, so lest imagine that it is necessary) And i want to inherit class like this: class SonClass : public Base{ public:     SonClass(int i): Base(i){}     int& at(size_t index){         do_something_more();         return Base::at(index);     }     const int& at(size_t index) const {         do_something_more();         return Base::at(index);     } };  It seems like the versions of the at function are both the same. Is anyways to avoid this? Or any better way to do it? It seems basic, but i have like 5 functions that are all the same because of this.


Could I make a persistent Ubuntu USB drive from Debian?

A lot of online tutorials say that I need to use mkusb on ubuntu to make a persistent ubuntu usb. Could I use mkusb on debian to make a persistent ubuntu usb?


Difference Between Permutations Divisible by 9?

Given a permutation, for example:  1234 1243  .  . 4321  Can anybody explain why the differences between numbers are always (no proof, but for all simple permutations) divisible by 9?


How can I launch a GameObject at a target if I am given everything except for its launch angle?

I am trying to launch an object at a target, given its position, its target position, the launch speed, and the gravity.  I am following this formula from :  $$ \theta = arctan \bigg( \frac{v^2 \pm \sqrt{v^4-g(gx^2 + 2yv^2)}}{gx} \bigg) $$  I have simplified the code to the best of my ability, but I still cannot consistently hit the target.  I am only considering the taller trajectory, of the two available from the +- choice in the formula.  Does anyone know what I am doing wrong?  using UnityEngine;  public class Launcher : MonoBehaviour {     public float speed = 10.0f;      void Start()     {         Launch(GameObject.Find("Target").transform);     }      public void Launch(Transform target)     {         float angle = GetAngle(transform.position, target.position, speed, -Physics2D.gravity.y);         var forceToAdd = new Vector2(Mathf.Cos(angle), Mathf.Sin(angle)) * speed;         GetComponent<Rigidbody2D>().AddForce(forceToAdd, ForceMode2D.Impulse);     }      private float GetAngle(Vector2 origin, Vector2 destination, float speed, float gravity)     {         float angle = 0.0f;          //Labeling variables to match formula         float x = Mathf.Abs(destination.x - origin.x);         float y = Mathf.Abs(destination.y - origin.y);         float v = speed;         float g = gravity;          //Formula seen above         float valueToBeSquareRooted = Mathf.Pow(v, 4) - g * (g * Mathf.Pow(x, 2) + 2 * y * Mathf.Pow(v, 2));         if (valueToBeSquareRooted >= 0)         {             angle = Mathf.Atan((Mathf.Pow(v, 2) + Mathf.Sqrt(valueToBeSquareRooted)) / g * x);         }         else         {             //Destination is out of range         }          return angle;     } }