Prove that the kernel of a homomorphism is a principal ideal. (Artin, Exercise 9.13)

I have been having trouble with an exercise in my abstract algebra course. It is as follows:     Let $f: \mathbb{C}[x,y] \rightarrow \mathbb{C}[t]$ be a homomorphism that is the identity on $\mathbb{C}$ and sends $x$ to $x(t)$ and $y$ to $y(t)$ such that $x(t)$ and $y(t)$ are not both constant. Prove that the kernel of $f$ is a principal ideal.


Can Thunder Gauntlets meet the material component requirement of Booming Blade and Green Flame Blade?

This is very related to this question:  This is to talk about the new rules introduced in TCoE with respect to Booming Blade and Green Flame Blade now needing "a melee weapon worth at least 1 sp" as the material cost (whereas before TCoE I believe it only needed a melee weapon) Specifically, when taking the Armorer subclass for an Artificer can you use the cantrips Booming Blade and Green Flame Blade with the Thunder Gauntlets provided by the Guardian Armor Model? This is intended to talk about whether or not properties of the "base armor" used for the Arcane Armor be transferred over to the extended parts of it (gauntlets, boots, helmet).  There is a thread that talks about the magical properties of the "base armor" and . So the way I see it there are 2 interpretations:  Properties of the base armor transfer over - Therefore your Thunder Gauntlets will have an associated cost related to your base armor and be able to use the cantrips Booming Blade and Green Flame Blade. However when using magical armor for your Arcane Armor you will not be able to infuse the "extremities" because the magical property was also transferred over.  Properties of the base armor are not transferred over - From a game mechanics perspective Thunder Gauntlets are considered separate items from the Arcane Armor and since no such item exists in the PHB the cost is undefined therefore unsuitable for the cantrips Booming Blade and Green Flame Blade. This does mean that while using magical armor as the Arcane armor the magical properties are not transferred over and the extremities are considered mundane objects with respect to infusions.   All in all, which interpretation is correct or is there another interpretation?


Issue after updating Facebook and Facebook gets update automatically

I have Realme Pro 2 (ColorOS 6 and Android 9). I updated Facebook from Play Store.  After update, the new version is Facebook 260  And the issue is:    Even I don’t this see option:   Then, I uninstalled and reinstalled Facebook and issue not resolved.  I downloaded previous version (250) and installed.  It’s okay and easy to use. Facebook 250 is working fine and I don’t want to update it. Auto-update is also OFF from Play Store. However, it gets updated automatically.  Pls let me know,  how to resolve issue with new version or how to stop it to get updates automatically?  Thank is advance.  Regards FewL


Better latex output, instead of being wrapped on Terminal?

Latex output is being wrapped, even if there is space on Terminal:    While if I list the files ls command output seems normal (as expected):    I checked  and tried export max_print_line=1000 but that gives:    Although export max_print_line=120 is better then nothing.  Why is so? How do I get LaTex to use all space available nicely? By nicely I mean, can it break line after close of parentheses?  Sorry 1: If this is not a LaTex issue (perhaps I should ask on stackoverflow or askdifferent?).  Sorry 2 : Because I changed question a bit, I think is not a duplicate now.


How do I add folder to GitHub? IT keeps saying On branch main nothing to commit, working tree clean

How do I add stuff? It doesn't work sorry I'm new to GitHub. I did git commit -m "HERE" but it still says the same?


If I graduated from a university (named X for example) in 2014 and my average (or GPA) was the highest among all students who graduated that year from the same major (let's call it Y). So I want to say in my CV that my rank was the first. How to say that in a proffesional way?  What I'm currently using:     Graduated from X with a B.Sc degree in Y with an average of 90% (class rank: 1)


Does the temperature of a body depend on the frame of reference?


How to navigate to standard Add Products dialog from a lightning component?

If you click Add Products or Edit Products on a quote record, a modal pops up. Is it possible to invoke this modal from a lightning component?


Does using a draconic sorcerer's Draconic Presence break concentration for a spell?

The feature  states  As an action, you can spend 5 sorcery points to draw on this power and exude an aura of awe or fear (your choice) to a distance of 60 feet. For 1 minute or until you lose your concentration (as if you were casting a concentration spell), each hostile creature that starts its turn in this aura must succeed on a Wisdom saving throw or be charmed (if you chose awe) or frightened (if you chose fear) until the aura ends.  Which would obviously mean that casting a spell after using Draconic Presence would break concentration. However, the rules for spell concentration states  Casting another spell that requires concentration. You lose concentration on a spell if you cast another spell that requires concentration. You can't concentrate on two spells at once.  But if you were to cast a concentration spell and use Draconic Presence, would the Spell effect end? Draconic Presence isn't a spell and it isn't even magical. It states the condition to losing Draconic Presence's concentration but it doesn't change that only concentration spells break a creature's concentration on another spell (that isn't damage). Is this correct or am I missing something?


"Closed as Duplicate" text is misleading when the duplicate is from the same user

was recently closed on Stack Overflow as a duplicate of another question.  That original question did not have any answers.  However, the close reason clearly states:     This question has been asked before and already has an answer. If those answers do not fully address your question, please .   First off, there are no answers, so the non-existant answer couldn't address the question.    Secondly, this makes it sound like if your question is closed as a duplicate, you should ask a new question.  That's not at all what we want, right?  I don't remember the text being like that before, but I could be wrong.


I have installed httpd 2.2.15 on CentOS 6.5 (minimal installation with no cPanel) with modsecurity 2.8. When I am starting httpd I am getting this error:  Starting httpd: Syntax error on line 23  of /etc/httpd/conf.d/modsecurity.conf:  ModSecurity: Found another rule with the same id   The line 23 is:  "id:'200000',phase:1,t:none,t:lowercase,pass,nolog,ctl:requestBodyProcessor=XML"


How to find all my edited questions/answers which are in pending approval(Queue)?

I have edited someone's question in stackoverflow.com. As I don't have enough reputation to edit a question/answer with out approval, my edit has been in queue for waiting approval. I closed that tab at that time but now I want to check whether my edit has been in queue or not. How can I check that?  I know in my profile page I have an optioned called '-- Posts Edited' but I'm sure it will show only when my edit has been approved.     But I want to check what are all the questions I have edited are in QUEUE Is it possible?  Note: This question might looks like a duplicate of  but my requirement is to see all the question which were declined or in Queue.    Here I can see only the approved edits/rejected edits. But I want to see edits in Queue just like approved edits :)


How can we reason about "if P then Q" or "P only if Q" statements in propositional logic?

When you have a propositional sentence of the form P ⊃ Q  — which we might read as "if P, then Q" — how can you tell when it is true, or false, based on the truth-values of P and Q in classical logic? When is this different from Q ⊃ P? And what is the connection to 'necessary' conditions, or sufficient conditions?  Also: does P ⊃ Q mean that P causes Q?


Finite ring zero divisor/multiplicative inverse

This is probably a pretty basic question but I'm an applied math guy trying to understand these basics: If a nonzero element of a finite ring does not have a multiplicative inverse, must that element be a zero divisor?    I've tried proving this to myself to no avail, and searches have only turned up some deep pure math stuff (as far as I'm concerned, anyways).  Thanks in advance!


What does change mean in weekly leagues summary?

I see my status below from     Now I can understand what others terms mean here like week rank, total reputation and week reputation. But what does change mean here?


Proof: $\mathrm{adj}(\mathrm{adj}(A)) = (\mathrm{det}(A))^{n-2} \cdot A$ for $A \in \mathbb{R}^{n\times n}$

I had my exam of linear algebra today and one of the questions was this one.  Given $ A \in \mathbb{R}^{n \times n}$, prove that:  $$\mathrm{adj}(\mathrm{adj}(A)) = (\mathrm{det}(A))^{n-2} \cdot A.$$  Of course I was not able to prove this identity, otherwise I wouldn't post it here. But I'm still curious how one can prove this identity.  Could someone point me in the right direction?


What word means what many people think 'ironic' means?

'Ironic' is often used to mean an unusual coincidence rather than its true meaning which is closer to sarcastic. That being said, is there a word that would be a good replacement for what many people seem to think it means?


I was wondering how can I alter this code to redirect me to any hyperlink.   function myDayClickHandler(eventObj) {     // Get the Date of the day that was clicked from the event object     var date = eventObj.data.calDayDate;     // store date in our global js variable for access later     clickDate = date.getFullYear() + "-" + (date.getMonth() + 1) + "-" + date.getDate();     // open our add event dialog     $('#add-event-form').dialog('open'); };   PS: I need the date and click date variable.   Thanks


I have a web-to-lead html form (generated form standard Salesforce functionality) and a duplicate rule.   I want to display a success and error message that whether lead is created or not after clicking on submit.


preg_match: between string and first non-alpha numeric character

I'm trying to extract text between a given string and first non-alpha numeric character. The code below works but it's using the  tag instead of \W.   $my_string = 'Auth code: 02452A
'; preg_match("~Auth code:(.*)
~",$my_string, $m); print_r($m); // shouldn't this work, too? preg_match("~Auth code:(.*)\W~",$my_string, $m);


Passport validity is less than 6 month on departure date

I plan to travel to India on Jan 30, 2021, with a green card valid until Dec 18, 2029, and an Indian Passport valid until April 4, 2021. Will there be an issue with my passport to travel to India? I shall be returning to the USA on June 30, 2021, with a renewed passport and valid green card. Will there be an issue with my travel or passport?


Unity question: When attaching my custom camera script camera shakes when player starts to move fast

Here is my player code.  Rigidbody rb;  Vector3 currMovement; public float jumpSpeed = 10; public float moveSpeed = 10; public float rotSpeed = 180;  float distToGround;  public float smoothTimePos = 0.25f; float currPos; float targetPos; float posVel;  public float smoothTimeRot = 0.25f; float currRot; float targetRot; float rotVel;  void Start() {     rb = GetComponent<Rigidbody>();     distToGround = GetComponent<Collider>().bounds.extents.y; }  bool isGrounded() { return Physics.Raycast(transform.position, Vector3.down, distToGround + 0.1f); }  void Update() {     targetRot = Input.GetAxisRaw("Horizontal") * rotSpeed * Time.smoothDeltaTime;     targetPos = Input.GetAxisRaw("Vertical") * moveSpeed; }  void FixedUpdate() {     Move(); }  void Move() {     if (isGrounded())     {         if (Input.GetButtonDown("Jump"))             rb.velocity += Vector3.up * jumpSpeed;     }      // Rotation smoothing.     if (targetRot > 360)         targetRot -= 360;     if (targetRot < 0)         targetRot += 360;     currRot = Mathf.SmoothDampAngle(currRot, targetRot, ref rotVel, smoothTimeRot);      transform.eulerAngles += new Vector3(0, currRot, 0);      // Movement smoothing.     currPos = Mathf.SmoothDamp(currPos, targetPos, ref posVel, smoothTimePos);     currMovement = new Vector3(0, 0, currPos);     currMovement = transform.rotation * currMovement;      rb.position += currMovement * Time.smoothDeltaTime; }   I have a Rigidbody attached to my player. I think the problem is with my camera script. Here is my camera script.  public Rigidbody player; Quaternion targetLook; Vector3 targetMove, targetMoveRaycast, targetMoveUse; public float smoothLook = 8, smoothMove = 0.25f; public float distFromPlayer = 5, heightFromPlayer = 3; Vector3 moveVel;  void LateUpdate() {     CameraMove(); }  void CameraMove() {     targetMove = player.position + (player.rotation * new Vector3(0, heightFromPlayer, -distFromPlayer));      RaycastHit hit;     if (Physics.Raycast(player.position, targetMove - player.position, out hit, Vector3.Distance(player.position, transform.position)))     {         targetMoveRaycast = hit.point;         targetMoveUse = targetMoveRaycast;     }     else     {         targetMoveUse = targetMove;     }      transform.position = Vector3.SmoothDamp(transform.position, targetMoveUse, ref moveVel, smoothMove);      targetLook = Quaternion.LookRotation(player.position - transform.position);     transform.rotation = Quaternion.Slerp(transform.rotation, targetLook, smoothLook * Time.smoothDeltaTime); }   The player is not an parent of my camera. When I parent the player to my camera the shake stops. But I want a custom smooth camera movement with my custom scirpt, so I can't make the player a parent of the camera.


How many devices should I connect to WiFi router for repeated transfer of data(IoT)

I have 10,000 machines (to make jute-bags), and each machine needs to send data to a remote server every 2 seconds. The data consists of machine id, machine state(on, off, error, needs human intervention, etc) and various other information collected from different sensors. I have successfully integrated the ESP8266 WiFi module with the machine. It collects all necessary data, and transmits it to the router, which then uses the internet to send that data to my remote server. As a demonstration to the factory management, I successfully sent data of 10 machines(through 1 single router) , every 2 seconds. But now, I have to do the same task for 10,000 machines. I have absolutely no idea as to how much bandwidth I need and how many machines I can connect to a single router? If my question seems incomplete, please feel free to ask me more questions. Thanks in Advance!


How to find out which application or service uses virtualization (AMD-V or VT-x) in Windows?

I am trying to run a virtual machine in VirtualBox, but it gives me the following error:  VBoxManage.exe: error: AMD-V is being used by another hypervisor. (VERR_SVM_IN_USE). VBoxManage.exe: error: VirtualBox can't enable the AMD-V extension. Please close all other virtualization programs. (VERR_SVM_IN_USE)  Is is possible to find out which program or service exactly has taken control of virtualization, so that I can uninstall it?


Kodi Failed Installation on Ubuntu 16.04

When I'm trying to install Kodi, I get:  root@xKaganovich:/home/kaganovich# apt-get install kodi Reading package lists... Done Building dependency tree        Reading state information... Done The following packages were automatically installed and are no longer required:   fonts-roboto fonts-roboto-hinted kodi-data libcec-platform1v5 libcec3   libfstrcmp0 libhdhomerun2 libjs-iscroll libsdl2-2.0-0 libsndio6.1 Use 'sudo apt autoremove' to remove them. Suggested packages:   kodi-pvr-mythtv kodi-pvr-vuplus kodi-pvr-vdr-vnsi kodi-pvr-njoy   kodi-pvr-nextpvr kodi-pvr-mediaportal-tvserver kodi-pvr-tvheadend-hts   kodi-pvr-dvbviewer kodi-pvr-argustv kodi-pvr-iptvsimple   kodi-audioencoder-vorbis kodi-audioencoder-flac kodi-audioencoder-lame The following NEW packages will be installed:   kodi 0 upgraded, 1 newly installed, 0 to remove and 1 not upgraded. Need to get 0 B/20.0 MB of archives. After this operation, 37.1 MB of additional disk space will be used. (Reading database ... 264739 files and directories currently installed.) Preparing to unpack .../kodi_2%3a17.6+git20171114.2125-final-0xenial_all.deb ... Unpacking kodi (2:17.6+git20171114.2125-final-0xenial) ... dpkg: error processing archive /var/cache/apt/archives/kodi_2%3a17.6+git20171114.2125-final-0xenial_all.deb (--unpack):  trying to overwrite '/usr/share/kodi/media/icon32x32.png', which is also in package kodi-data 15.2+dfsg1-3ubuntu1.1 dpkg-deb: error: subprocess paste was killed by signal (Broken pipe) Processing triggers for man-db (2.7.5-1) ... Processing triggers for menu (2.1.47ubuntu1.16.04.1) ... Errors were encountered while processing:  /var/cache/apt/archives/kodi_2%3a17.6+git20171114.2125-final-0xenial_all.deb E: Sub-process /usr/bin/dpkg returned an error code (1)   How can i fix this problem?


Vertical spacing suddenly changes as I am writing a document

This has happened a few times and I don't know how to diagnose the issue. Below is the code which is as simple as I can get to reproduce the problem.  The vertical spaces between a lot of the lines is far too large suddenly. Removing something like the title or the description environment suddenly fixes it. I cannot target the problem.  \documentclass{amsart} \usepackage{amsthm} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{amssymb}  \newenvironment{problem}[2][Problem]{\begin{trivlist} \item[\hskip \labelsep {\bfseries #1}\hskip \labelsep {\bfseries #2.}]}{\end{trivlist}}  \title{title} \author{author}  \begin{document} \maketitle  \begin{problem}{2.32}     Suppose that $\mu(X)<\infty$. If $f$ and $g$ are complex-valued measurable functions on $X$, define:         \[\rho(f,g) := \int\frac{|f-g|}{1+|f-g|}\,d\mu.\]     Show that $\rho$ is a metric on the space of measurable functions if we identify functions which are equal $\mu$-a.e.. Moreover, $f_n\to f$ with respect to $\rho$ if and only if $f_n\to f$ in measure. \end{problem} \begin{proof}     First we need to show that $\rho(f,g)<\infty$ and that if $f$ and $f'$ are equal $\mu$-a.e., then $\rho(f,g) = \rho(f',g)$. Note that the integrand of $\rho$ is bounded above by 1 and $X$ is of finite measure, thus $\rho(f,g)$ is finite for any $f$ and $g$ (being bounded above by the integral of $\chi_X$). Then note:     \[|f-g| = |f-g| + |f'-f| \geqq |f-g+f'-f| = |f'-g|, \text{ $\mu$-a.e.},\]     and similarly, we can get the opposite inequality by swapping roles of $f$ and $f'$. Thus $|f-g| = |f'-g|$, $\mu$-a.e. and then the well-definedness of $\rho$ follows as the integrands of $\rho(f,g)$ and $\rho(f',g)$ are $\mu$-a.e. equal.  Now to prove that it is a metric:     \begin{description}         \item[Indiscernibility] Note that if $f=g$ $\mu$-a.e., then clearly $|f-g| = 0$ $\mu$-a.e., and hence $\rho(f,g)$ is the integral of a $\mu$-a.e. zero function---hence it is zero. On the other hand, if $\rho(f,g) = 0$, then we know that the integrand (being in $L^+$) is zero, $\mu$-a.e.. Thus $|f-g|$ is zero, $\mu$-a.e. and thus $f=g$ $\mu$-a.e.. Hence:             \[\rho(f,g) = 0 \iff f = g, \mu\text{-a.e.}.\]         \item[Symmetry] Note that $|\cdot-\cdot|$ is symmetric, and thus $\rho$ inherits this symmetry as the integrand is symmetric in $f$ and $g$. It also might be worth mentioning that the integrand is positive, so $\rho\geqq 0$.         \item[$\blacktriangle$-inequality] Note\footnote{Meanwhile also noting that $0\leqq x<y\implies \frac{x}{1+x} < \frac{y}{1+y}$. To deduce this, just take its derivative to note it is increasing.}:             \begin{align*}             \rho(f,h)             &= \int\frac{|f-h|}{1+|f-h|}\,d\mu\\             &= \int\frac{|f-g+g-h|}{1 + |f-g+g-h|}\,d\mu\\             &\leqq \int\frac{|f-g| + |g-h|}{1 + |f-g| + |g-h|}\,d\mu\\             &= \int\frac{|f-g|}{1 + |f-g| + |g-h|}\,d\mu + \int\frac{|g-h|}{1+ |f-g| + |g-h|}\,d\mu\\             &\leqq \int\frac{|f-g|}{1 + |f-g|}\,d\mu + \int\frac{|g-h|}{1+ |f-g|}\,d\mu\\             &= \rho(f,g) + \rho(g,h).             \end{align*}     \end{description} \end{proof} \end{document}   A comparison of before and after commenting out the \maketitle:   Maybe it has something to do with page breaks...?


There is my code which adds class 'nav-pills' to element with class 'nav-tabs' when window width is lower than 768px.  $(window).on('resize', function () { $('.nav-tabs').toggleClass('nav-pills', $(window).width() < 768); });   I want to alert something when user click link inside DOM element with these 2 classes (nav-tabs and nav-pills). But nothing happend.  $(".nav-tabs.nav-pills a").click(function(){     alert('test'); });   jQuery toggleClass works fine and add 'nav-pills' to 'nav-tabs' element (I checked it in chrome inspector), but alert wont work.   Anyone can help me?


Unable to boot into Windows after installing Ubuntu, how to fix?

I installed Windows on my computer, followed by an installation of Ubuntu. However, now I'm unable to boot into my Windows install.  What can I do to fix this?


Why does  require approval (and gives me 2 reps) while  didn't? Is the retag privilege gone?


What is the default location for rsync uploads?

I uploaded a local text file omitting the remote location and can't find the file (Ubuntu 16.04).  rsync -chavzP dump.sql user@ip-address   It's not in my home directory or anywhere else that I can tell:  find / -name dump.sql -print   I can re-upload with a remote location, but would like to at least find and remove that 6GB dump that I'm not using.


Insert statement performance in SQL Server

I have the below Insert statement query as part of an stored procedure that is taking some time to be complete (20-30) minutes, when normally in another server with same hardware specifications takes 1-2 minutes  Query:  INSERT INTO [DBO].[cond]     (        [LAST_NAME]      , [FIRST_NAME]      , [MIDDLE_NAME]      , [BUSINESS_NAME]      , [TIN]      , [date_of_birth]      , [OCCUPATION]      , [CTR_TRANSACTION_FK]      , [CREATED]      , [CREATED_BY]      , [LAST_MODIFIED]      , [LAST_MODIFIED_BY]      , [CTR_FK]      , [CUSTOMER_FK]      , [cust_type_FK]      , [gender]      , [naics_code]      , [name_suffix]      , [alternate_name]      , [extra_type]      , [ID_ISSUING_COUNTRY_FK]      , [id_issuing_state]      , [ID_TYPE]      , [ID_NUMBER]      , [FLEX_1]      , [FLEX_2]      , [FLEX_3]      , [FLEX_4]      , [ID_TYPE_OTHER_DESCRIPTION]      , [person_involved_source]      , [person_involved_date]      , [DEPOSITOR]     )     OUTPUT    [INSERTED].[ID]      , [INSERTED].[customer_FK]      , [INSERTED].[CTR_TRANSACTION_FK]      , [INSERTED].[CASHTX_CUSTOMER_FK]        INTO [#COND_INSERTED]     SELECT    [cust].[last_name]      , [cust].[first_name]      , [cust].[middle_name]      , [cust].[COMPANY_NAME]      , [foi].[identification_number]      , [cust].[birth_incorporation_date]      , [cust].[occupation]      , NTRX.[CTR_TRX_ID]      , @FilingDateTime      , @Filer      , @FilingDateTime      , @Filer      , NTRX.[CTR_ID]      , [cust].[id]      , [cust].[customer_type_FK]      , [cust].[GENDER]      , [cust].[NAICS_CODE]      , [cust].[SUFFIX]      , NULL      , CASE        WHEN [cashmap].[cb_type] = 'C'        THEN 'Conductor'        WHEN [cashmap].[cb_type] = 'O'        THEN 'Common Carrier'        ELSE ''    END      , [ctry1].[id]      , [cust].[id_issuing_state]      , [cust].[id_type]      , [cust].[id_number]      , [cashmap].[FLEX_1]      , [cashmap].[FLEX_2]      , [cashmap].[FLEX_3]      , [cashmap].[FLEX_4]      , [cust].[ID_TYPE_OTHER_DESCRIPTION]      , 1      , [cust].[LAST_MODIFIED]      , [cashmap].[DEPOSITOR]     FROM  [DBO].[cashcust] AS [cashmap]       INNER JOIN [DBO].cust AS [cust] ON [cashmap].[CUSTOMER_FK] = [cust].[id]       LEFT JOIN [DBO].custf AS [foi] ON [foi].[customer_FK] = [cust].[id]       LEFT JOIN [DBO].country AS [ctry1] ON [cust].[id_issuing_country] = [ctry1].[fincen_code]       INNER JOIN [DBO].trans AS [TXN] ON [txn].[UNIQUE_TRANS_ID] = [cashmap].[transaction_id]                AND txn.INSTITUTION_FK=cashmap.INSTITUTION_FK       LEFT JOIN [DBO].custacc AS [custmap] ON [txn].[account_FK] = [custmap].[account_FK]                 AND [custmap].[mapping_type] = 1                 AND [custmap].[IS_ACCOUNT_HOLDER] = 1                 AND [cashmap].[customer_FK] = [custmap].[customer_FK]       JOIN [#TMP_INSERTED] AS NTRX ON NTRX.TRX_ID=[txn].[id]     WHERE  [cashmap].[conductor_bene] = 'C'       AND @SourceConBenFromTellerFile = 0       AND ISNULL([cashmap].[has_error], 0) = 0;   Execution Plan: I noticed that the heaviest operator is the Clustered Index Insert.    Note: First set of inserted row was: 4810       Second set of inserted row was: 4886       Third set of inserted row was: 62  So not sure why is taking that time to insert them.      Important Server Info: MaxDOP = 4. Cost Treshold of Parallelism = 5  Top Waittypes:   Page life expectancy  =                                                                                60  Also I noticed some implicit conversion warnings in some of the insert statements:    Full Execution Plan: Part 1:   Part 2:   Part 3:   Memory Clercks for Blocking:


How to ask a question about a person's order among her /his siblings?

In most of the indian languages ,there is a WH question word used to ask about  a person's order among ones siblings . That is if she/he is the first , second or third child of ones parents. How to inquire about the same in English.Can we say?  How manieth child of your parents are you? or situation like as below  What is the order of Donald Trump among the presidents of USA?


linear combination and univariate normal

Show that $(X_1,X_2)$ has a bivariate normal distribution with means $\mu_1, \mu_2$, variances $\sigma _1^2 $ and $\sigma _2^2$, and correlation coefficient $\rho $ if and only if every linear combination $t_1X_1+t_2X_2$ has a univariate normal distribution with mean $t_1\mu_1+t_2\mu_2$, and variances  $t_1^2\sigma _1^2+t_2^2\sigma _2^2+2t_1t_2\rho \sigma_{12}$ where $t_1, t_2$ are non zero constants  My work:  Joint mgf of $X_1 $and $X_2=e^{[t_1\mu_1+t_2\mu_2+\frac{1}{2}(t_1^2\sigma _1^2+t_2^2\sigma _2^2+2\rho \sigma_1 \sigma_1t_1t_2 )]} $  I am confused here to find the proper grouping to get the forward result.  For the backward result, I know I have to find the m.g.f. of $t_1X + t_2Y$, for any $t_1 $and $t_2$ real,and plug in the $E(t_1X + t_2Y)$ and $Var(t_1X + t_2Y)$.  I am struggling to get the correct backward result.  Second part:   Let $Y_i=X_i/\sigma_i, i=1,2$ Show that $Var(Y_1-Y_2)=2(1-\rho)$  I have found, $Var(Y_1)=\sigma_1, Var(Y_2)=\sigma_2$ since $X_1/\sigma_1=\sigma _1$  How can I prove that $Var(Y_1-Y_2)=2(1-\rho)$? Thank you so much for your help!


How to resize a screenshot image on a Mac so that it is "regular size" when posted on the Internet?

Short question: why if I do screenshot on a Mac and crop it, and see it using Preview, it is a good size but when posted to Internet, such as StackOverflow, its width and height always double? I can resize 50% width and height but the image is not as clear (not retina). So how can I use that image and not have it show up twice the width and height?)    I sometimes take a screenshot on a Mac (OS X Mavericks), by CMD-Shift 4, and resize it to 50% width and height in Preview.  But when posted on the Internet (for example, on an online forum or on ibb.co or imgur.com) , it is double size again. I tried 50% and then resolution changed from 144 to 72 for the original image, and the same: it is still double size.  I had to do a 25% and also 72, in order that it is the proper size.  It is really weird. Why 25% and not 50%, and how does the 144 or 72 matter? (or does it?)


Listings: text highlighting based on prefix

How can I apply different styles to keywords depending on their prefix?  Here is some sample code:  (-2,0,0) (2,1,1) op-registerbox !box1 ;box1 /Blue op-setproperties   I'd like to typeset   words starting with ! and ; in color red, words starting with / in color green, words starting with cp- in bold.   So far, this is what I've got:  \lstdefinelanguage{XX} { basicstyle=\small\sffamily\fontseries{c}, emphstyle=\underbar, keywordsprefix=[2]{/}, alsoletter={/}, keywordstyle=\textbf, keywordstyle=[2]\color{green}, morekeywords={op,registerbox, ...}, morestring=[b][\color{green}]", columns=flexible, escapechar=\%, numbersep=6pt, numberstyle=\scriptsize }   I'm aware that only one keywordsprefix can be defined at the moment: specifying more than one class of prefix (keywordsprefix=[2]{/}) is currently not supported. I'd like to avoid having to list all the words that match my description into morekeywords. Is that possible? How?


Why can we pick the divergence of the vector potential?

I'm aware that the vector and scalar potential in E&M can be modified using a function $\lambda(t)$ in the following way:  $$\mathbf{A}' = \mathbf{A} + \nabla\lambda,\;\; \textrm{ and } \;\;\Phi' = \Phi - \frac{\partial\lambda}{\partial t}.$$  However, I'm confused when Griffiths claims that we can merely choose $\nabla\cdot\mathbf{A} = 0$ as in the Coulomb gauge, or $\nabla\cdot\mathbf{A} = -\mu_0\epsilon_0\dfrac{\partial \Phi}{\partial t}$ as in the Lorenz gauge. How is it that we know that such choices for $\nabla\cdot\mathbf{A}$ are valid? What are we allowed to choose for $\nabla\cdot\mathbf{A}$ and why?  Edit: This question  doesn't explain why there's always a solution to $\nabla^2 \lambda = -\nabla \cdot \mathbf{A}$.


My wife is a naturalised UK citizen from Gambia. Her brother is 17 and in Italy with a Permesso di Soggiorno.   Would he need a visa or would he be able to join us in the UK immediately?   If he arrived in the UK with the residence permit and a Gambian passport and evidence that they are brother and sister would he be allowed in?   Would he be allowed to board an aircraft in Italy without a visa stamp in his passport?   We are trying to do it quickly before he turns 18 in July.


$$ \sum_{b=1}^{n} \left\lfloor\frac{n}{b} \right\rfloor $$   I can't figure out how to convert this into a closed form.  Edit: I often come across summations I'm unable to solve. Is there some resource from which I can learn/practice solving complex summations. I hate asking numerous small questions of the same type repeatedly so if you could give some advice, I would be really grateful.


What's the Maclaurin Series of $f(x)=\frac{1}{(1-x)^2}$?

This function seemed to be pretty much straight forward, but my solution is incorrect. I have two questions: 1. Where did I make a mistake? 2. I learned that there are shortcuts for finding a series (substitution / multiplication / division / differentiation / integration of both sides). Is there something that I can apply here?  $$f(x)=\frac{1}{(1-x)^2}  \qquad  f(0)=1$$ $$f'(x)=\frac{2}{(1-x)^3}  \qquad  f'(0)=2$$  $$f''(x)=\frac{6}{(1-x)^4}  \qquad  f''(0)=6$$  $$f'''(x)=\frac{24}{(1-x)^5}  \qquad  f'''(0)=24$$  $$f''''(x)=\frac{120}{(1-x)^6}  \qquad  f''''(0)=120$$ The series is then $$1+\frac{2x}{2!}+\frac{6x^2}{3!}+\frac{24x^3}{4!}+\frac{120x^4}{5!}$$ and when simplified is  $$1+x+x^2+x^3+x^4$$ But the correct answer is  $$1+2x+3x^2+4x^3+5x^4 $$


How do you customize Excel 2010 keyboard shortcuts?  This article from microsoft.com provides instructions for "Microsoft Office 2010" but seems only apply to Word, not Excel.   In Microsoft Office 2010:  Click the File tab to open Backstage view, and then click Options.  Click Customize Ribbon and then, next to the Keyboard Shortcuts heading, click Customize. You can enter the new key combination here.    Here's the dialog it points to shown in Word:  But here's the same dialog shown in Excel:  Notice it looks almost exactly the same but no "Keyboard Shortcuts: Customize.." button. So how do you customize the keyboard shortcuts in Excel?


Prove: if $|z|=1$ than $\frac{z+1}{z-1}$ is an imaginary number    I have tried to look at $$\frac{z+1}{z-1}=\frac{z+1}{z-1}\cdot \overline{\frac{z-1}{\overline{z-1}}}=\frac{z+1}{z-1}\cdot \frac{\overline{z}-1}{\overline{z}-1}$$  But did not get far


Multiple one to many relationships in series

I am making a DB for storing reports that have following fields:  Ad_system, Ad_Campaing, Ad_Group, Keyword, Date, Impressions, Clicks, Conversions   Logic is that, Ad_system can have multiple Ad_Campaings, Ad_Campaing can have multiple Ad_Groups and Ad_Groups can have multiple Keywords, and for every Keyword there is a report. Should It be like this? Because it kind of makes sense to me, but it doesn't look correct. Primary key can also be:  ad.system.name for first table  ad.system.name ad.campaing.name for second table  ad.system.name ad.campaing.name ad.group.name for third table  ad.system.name ad.campaing.name ad.group.name keyword for fourth table  They will always be unique, but then Report will always have all DB columns in it, so it's kind of redundant.  Is the approach that I have in the diagram below correct? Or is a better one what I just described? If I am not mistaken both should satisfy 3rd NF.


I am using MacBook Pro 13 .current OS X El Capitan

How to upgrade the current OS X El Capitan (10.11.6)to “ high Sierra” As the current os ( X El Capitan) is very old not supporting few features. Anandarao n


so far all bounties I have been awarded I have gotten after the grace period, is this just coincidence?

I have recently won a few bounties on stackoverflow. (I knew I would get them because the awarders told me in the comment they would give them to me or had flagged the answer as right) I eventually was awarded the bounty but I actually could not see it until after the grace period was over.   this lead me to thinking, at first, that the awarders had forgotten to click the +50 button bellow my answer. still I ended up getting the bounties despite caducation afterwards !?!?  so my question is: what is going on? Is it that I was awarded the bounties on time but I will always see them only after the grace period has passed? did my awarders just forget? or did they award the bounty close to the deadline but stackoverflow uses some distributed DB system that only syncs every so many hours?  I am usually pretty eager to anwser questions with bounties and I put quite a bit of effort into them (cause Im a victim of gamification and incentives XD, long live capitalism) but I wouldn't want to be unnecessarily pushy on awarders if its not on them.


How to calculate $\int\limits_{-\infty}^\infty\frac{e^{ix}}{x}dx$

I need to calculate    $$I_0=\int_{-\infty}^\infty\frac{e^{ix}}{x}dx=\lim_{R\rightarrow\infty}\int_{-R}^R\frac{e^{ix}}{x}dx=\lim_{R\rightarrow 0}(\lim_{\varepsilon\rightarrow 0}(\int_{-R}^\varepsilon\frac{e^{ix}}{x}dx+\int_{-\varepsilon}^R\frac{e^{ix}}{x}dx))=\lim_{R\rightarrow 0}(\lim_{\varepsilon\rightarrow 0}I(R,\varepsilon))$$   I have tried to close the contour of the complex integral on the complex plain. Let $C$ be the semicircle with radius R above the real axis and $\gamma$ be the semicircle under the real axis with radius $\varepsilon$, both centered at $O$. Let $L$ be the closed contour contained $C,[-R,-\varepsilon],\gamma,[\varepsilon,R]$. Denote the $+$ direction by the $+$ direction of $L$. Then we have:  $$\int_{L^+}\frac{e^{iz}}{z}dz=I(R,\varepsilon)+\int_{C^+}\frac{e^{iz}}{z}dz+\int_{\gamma^+}\frac{e^{iz}}{z}dz$$  By Cauchy Integral Formula we have $\int_{L^+}\frac{e^{iz}}{z}dz=2\pi i$ so  $$I(R,\varepsilon)=2\pi i-\int_{C^+}\frac{e^{iz}}{z}dz-\int_{\gamma^+}\frac{e^{iz}}{z}dz$$  Take $\varepsilon\rightarrow 0$ we have:  $$I(R,0)=\pi i-\int_{C^+}\frac{e^{iz}}{z}dz=\pi i-\int_0^{\pi}\frac{e^{iRe^{i\phi}}}{Re^{i\phi}}iRe^{i\phi}d\phi$$  $$=\pi i-i\int_0^\pi\exp(iR(\cos\phi+i\sin\phi))d\phi=\pi i-i\int_0^\pi e^{iR\cos\phi}e^{-R\sin\phi}d\phi$$  Now I must take the limit $R\rightarrow\infty$. I evaluate:  $$\left|\int_0^\pi e^{iR\cos\phi}e^{-R\sin\phi}d\phi\right|\le\int_0^\pi e^{-R\sin\phi}d\phi$$  Is there anything wrong in my argument so far? How can I proceed further?  EDIT1: Looking at it for quite long I think I can write  $$\int_0^\pi e^{-R\sin\phi}d\phi=2\int_0^{\pi/2} e^{-R\sin\phi}d\phi\le 2\int_0^{\pi/2} e^{-R\frac{\phi}{2}}d\phi=\frac{4}{R}(1-e^{-R\frac{\pi}{4}})\le\frac{4}{R}$$  So in the end take $R\rightarrow\infty$ we get $I_0=i\pi$. Is it true?


At the airport in-person check-in time when the flight is delayed

If a flight is delayed, and they announce in advance the delay, is the check-in time also delayed?   Say, at 13h, the flight, that was scheduled for 16h, has an estimated departure for 16h30. If in-person at the airport check-in time was 15h20, is check-in time 15h50 now?   Edit:   Somehow this  answers my question.


Characteristic function of $Y=X_1X_2$, where $X_1$ and $X_2$ are standard normal

Let $X_1$ and $X_2$ be real-valued independent random variables with a standard normal distribution. Let $ Y = X_1X_2$. Find the characteristic function of Y.  Attempt:  $\phi_{Y}(t)$ = $\frac{1}{\sqrt{2\pi}}\int_{-\infty}^{\infty} exp(it(x_1x_2))exp(-1/2(x_1x_2)^2)dx_1dx_2$  I know that the standard normal characteristic function is:  $\phi_{X_1}(t)$ = $exp(\frac{-t^2}{2})$ and likewise for $X_2$  However, I'm not sure what the resulting product is. I realize that I can use a Jacobian, but I'd like to keep it simple and see if there is a way to derive the characteristic function with something easier.


We are given an  infinite nested radical as follows  $$\sqrt{1+\sqrt{2+\sqrt{3+\cdots}}},$$  which can be proven that it is convergent, namely, is equal to a real constant.  For this purpose, we consider applying the monotone convergence principle. Since its monotone property is obvious, what we need is to show it is bounded above.  First, we claim      $${\frac{n}{2^{2^{n-1}}}\leq 1(\forall n)}$$   $Proof~~~~$ It's easy to show $2^{n-1}\geq n.$ For $n=1,2$, it holds trivially. For $n \geq 3$, by Newton's binominal theorem, we have $$2^n=(1+1)^n=\binom n0+\binom n1+\cdots+\binom n{n-1}+\binom nn\geq 1+n+n+1\geq 2n.$$ Thus $2^{n-1}\geq n$. Furthur, $2^{2^{n-1}}\geq 2^n \geq 2^{n-1}\geq n,$ which implies ${\dfrac{n}{2^{2^{n-1}}}\leq 1(\forall n)}$.  Next, we claim     $${ \sqrt{1+\sqrt{1+\sqrt{1+\cdots}}}<\infty}.$$   This is a well-known result. In fact, substituting $1$ among here for any $a>0$, it's also true. For the recursion $x_1=\sqrt{a},x_n=\sqrt{a+x_{n-1}}(n\geq2)$, we can show that $a_n\leq a$, just by mathematical induction.  Now, go back to the present problem. Notice that  \begin{align*} \sqrt{1+\sqrt{2+\sqrt{3+\cdots}}}&=\sqrt{2}\cdot\sqrt{\frac1 {2}+\sqrt{\frac2{2^2}+\sqrt{\frac3{2^4}+\cdots}}}\\ &\leq\sqrt{2}\cdot\sqrt{1+\sqrt{1+\sqrt{1+\cdots}}}\\ &<\infty, \end{align*}  which is desired.  But, my question is that, can we evaluate it? In another word, can the limit be expressed as an elementary closed form?


Prove if given L|M and gcd(M, D) = 1, then gdc (D, L) = 1 is true

I want to prove if given $L|M$ and $gcd(M, D) = 1,$ then $gdc (D, L) = 1$ is true (As stated in the title) This seems very easy, yet I am having trouble on where to really start? I feel like Bezout's Identity should be used here, however I don't know how to really apply it. Any suggestions, or beginning steps would be gladly appreciated


In the chat, we often use backticks highlight code inside of sentences, exactly like how we do it here.  Unfortunately, it's located peculiarly close to the esc key, which has a nasty effect of clearing the chat input.  Outside of making a userscript, would it be alright to disable that effect so that I (and probably a bunch of others) don't throw my computer out the window when I lose a larger post to a misplaced keystroke?  Note: command+z (OSX) does not undo the delete.


Is there a word for happiness made possible by a tragic situation?

I frequently find myself needing a word to express happiness that acknowledges a tragic or unfortunate circumstance underpinning that happiness. Preferably the word could have both adjective and verb forms. For example, "Gregory [verb-ed | felt adjective about] the balmy February day, suspecting it was yet another consequence of catastrophic and irreversible climate change."  "Bittersweet" is close, but not precisely right. It implies ambivalence rather than genuine gladness. "Schadenfreude" is also in the neighborhood, but I don't want to imply that the tragic part of the situation is what causes the pleasure. (Also, I recognize that the word may not quite exist in English, and I don't know if this is forbidden for this forum, but I'd welcome a loan word or phrase if there's a better one.)


Difference between "has + verbed" and "had + verbed"

This is something which came up in my .   As far as I know "had + verb" is done (started & finished) in the past. What's about "has + verb"? Can anyone please explain me the difference?


How to set default options for mounted file systems?

I would like all FAT volumes to be mounted with the option uni_xlate enabled.  How can I configure mount or udisks2 to use that option while mounting the volume?


Why do most flags get closed quickly, but some linger?

I'm fairly new to contributing, but I've been trying to flag questions that are obviously off-topic when I see them.  Most of my flags get responded to almost immediately, but it seems like some linger for a long time, and I'm just kind of curious why.  Example:   It's clearly off topic, I voted it as off-topic, but it's still active almost a month after my flag.  It's not a big deal, I'm just curious why.  Thanks!


Find out which process is locking a file or folder in Windows

How can I find out which process is locking a file or folder in Windows?  For instance, when trying to delete a folder, Windows reports this:     The action can't be completed because the folder is open in another program   Happens the same with a file, but how do I find out what program or application is currently using it and preventing me from deleting the file or folder?


Prove if $f:[a,b] \rightarrow \mathbb{R}$ is integrable, then so is $|f|$ and $\left|\int_{a}^{b}f(x)dx\right| \leq \int_{a}^{b}|f(x)|dx$

Prove that if $f:[a,b] \rightarrow \mathbb{R}$ is integrable, then so is $|f|$ and $\left|\int_{a}^{b}f(x)dx\right| \leq \int_{a}^{b}|f(x)|dx$   I already proved that |f| is integrable, but how do I show that $|\int_{a}^{b}f(x)dx| \leq \int_{a}^{b}|f(x)|dx$   ?


Can anyone help me with this question:  I know i asked a similar question not a while ago but i'm not able to understand how its possible. If anyone could give me a lot of examples instead of an answer.  I need to find the regular expression for this language: L=all words that have 00 or 11 but not both.  Thank you!


Since I'm not a native speaker, I've encountered the two examples that makes me confused..  Here are the examples:   "I still dream of THEM wolves, THOSE endless prairies." "First of THEM true loves singing on the shoulders."   Please, could anyone explain me why THEM/THOSE were put at all, is it because of the emphasizing?  In the first sample the both nouns are in the plural form, then why in the first one is THEM and in the second THOSE? And in the second sample why is there THEM, if the sentence might have been worked without it?


what happens if both try and finally returns boolean in a method

I have a class- public class Check {  public static void main(String[] args) {     System.out.println(new Check().isRight()); }   public boolean isRight(){     try{         return true;     }finally{         return false;     } }   The method isRight has return true and false in finally clause , and finally it returns me false as finally clause will surely be called, so whats actually happening the data inside try.  I need to know the logical reason behind the output , I read but couldn;t understand properly.


Upgrading to 14.04 didn't update my kernel

I've updated my Ubuntu version from 13.10 to 14.04 last week using the update-manager.  However, my kernel version did not update:  $ uname -r 3.11.0-12-generic $ lsb_release -a No LSB modules are available. Distributor ID:  Ubuntu Description:     Ubuntu 14.04 LTS Release:         14.04 Codename:        trusty   This makes virtualbox and any other thing that needs updated linux-headers to not work (The old 3.11 linux-headers are not present in the repo).  I know  but I want to use the default kernel that came with trusty (I think it's 3.13.0-24), so that I know everything is supported.  How can I update my kernel to the correct version?


How do I remove Windows 7 from my dual boot system with Ubuntu?

Hello can someone give me short tutorial how to:   Remove Windows 7 from my dual boot system (Ubuntu/Windows7) Let me use free space as new partition for data (so I don't need to extend Ubuntu itself here) Remove windows 7 option from boot screen   Update:  Thanks to Lekensteyn answer I successfully deleted windows. Now I created new partition (formatted to ext4), but I can not use it. I cannot copy files there, only as root.  Also when booting, Ubuntu complains it didn't find /windows partition (of course it didn't, I removed it). I feel like I should update some tables or what, any ideas?


New generation of Save icon that is not a "disk"?

Currently, the save icon in almost all applications represents a 3.5-inch disk from the 20th century. An example from Microsoft Office 2010 is shown below:    As we move towards more advanced technology, this "disk" save icon now seems obsolete. Kids born in 21st century might not even know what a disk is.  Is there any good alternative save icon out there that can replace this "disk" save icon in applications? Or, probably we can design a new save icon here and make it a standard? Ideally, the icon should not represent any hardware, because it will become obsolete again as technology evolves.  Very IMPORTANT Note:   This question is NOT to discuss whether we should change the "disk" save icon or not. I know the icon is still perfectly OK and friendly to the end users. There are questions on   and  that discuss this.   I just want to look for good "save" icon that does not look like a disk (or hardware). Just take this question as a brainstorming or a design challenge. :)  At least one save icon image per answer please.


Tangent half angle subsititution (Integration Query)

How would you go about solving something like $$\int \frac{1}{4+5\cos{t}}~dt$$  I am aware that you would use a substitution involving the half angle of tan but I am unsure on how to apply it.  Many thanks


Picking out items from a python list which have specific indexes

I'm sure there's a nice way to do this in Python, but I'm pretty new to the language, so forgive me if this is an easy one!  I have a list, and I'd like to pick out certain values from that list. The values I want to pick out are the ones whose indexes in the list are specified in another list.  For example:  indexes = [2, 4, 5] main_list = [0, 1, 9, 3, 2, 6, 1, 9, 8]   the output would be:  [9, 2, 6]   (i.e., the elements with indexes 2, 4 and 5 from main_list).  I have a feeling this should be doable using something like list comprehensions, but I can't figure it out (in particular, I can't figure out how to access the index of an item when using a list comprehension).


What is the exposure triangle? How do the "sides" affect my photographs?


Images as planes appears always in front

I am using the images as planes addon and when I add an image it always appears on top no matter how I rotate, I don't know if this is intentional but it didn't use to be like that. I am using 2.90.1 Here are some images explaining. Image A and B are centered in 0,0,0 and they are intersectin in the middle and are perpendicular, yet B appears on top always since I added it after A. I add a screenshot with the bug, and a screenshot of how it should look. And no, it is not a matter of the visibility in the viewport display, it is not x-ray, "in front" is not selected. So I solve it by deleteing the material and adding it again, which doesn't make sense. Any clues? How it looks  How it should look


What is the difference between "might be" and "would be"?

To me both might and would appear to have similar meaning. E.g. consider the following sentences:.         I think taking some rest after work would be good.     I think taking some rest after work might be good.      The only difference I see is that would sounds more assuring than might. That is, in #1 speaker is more inclined to accept the fact that having some rest will be good, but in #2 speaker isn't sure about it. In #2 it is like 50/50, it can be good and it cannot be.     So, what is the difference between would and might?


How does the I2OSP primitive in RSA work?

I'm trying to figure out how to convert a message to a message representative (non-negative integer) in RSA. I think I understand how the OS2IP primitive (converting from message to integer). It involves finding the sum of all the integer representations of each byte multiplied by 256 to the power of the length of the message minus the index for the byte. However, I don't understand how the opposite process works. PKCS#1 says to write the message representative x in its    xLen-digit unique representation in base 256. I'm not very good with the actual mathematical processes here, so I'm not sure how the integer is supposed to be separated into the separate bytes multiplied by powers of 256.


string = "ABCDEFGH"   Can anyone explain why in string[start:end:stride]  the start always starts from 0 while end starts with 1.  For example string[0:3:1] outputs the result as "ABC". As you can see I said end = 3 so shouldn't the string[0:3:1] be "ABCD" because computer read 0 first?  And one more thing why: I don't get a result for  string[0:8:-1]. Shouldn't it be "HGFEDCBA"? I don't know if it is wrong syntax or not but I can print the result of string[::-1].


Find the degree of the extension of $\sqrt{3+2\sqrt{2}}$ over $\mathbb{Q}$.

I have done the following work:  Let $\alpha = \sqrt{3+2\sqrt{2}}$. Square both sides, so $\alpha^2 = 3+2\sqrt{2}$.  Then $(\alpha^2 - 3)^2 = (2\sqrt{2})^2$. Simplify, we can get $\alpha^4-6\alpha^2+1=0$. This means that $\alpha$ is a root of the monic polynomial $p(x)=x^4-6x^2+1 \in \mathbb{Q}[x]$. Then this means $\alpha$ is algebraic over $\mathbb{Q}$.  Now, if $p(x)$ is irreducible over $\mathbb{Q}$, then the degree of the extension field $\mathbb{Q}(\sqrt{3+2\sqrt{2}})$ is equal to the degree of $p(x)$, which is 4. However, $p(x)$ is reducible over $\mathbb{Q}$ since \begin{align*} p(x)&=x^4-6x^2+1\\ &=(x^4-2x^2+1)-4x^2\\  &= (x^2-1)^2-4x^2\\ &=(x^2-2x-1)(x^2+2x-1) \end{align*} I saw another post saying that this means the degree of the extension field is 2. I don't understand this at all. Could someone help me with this? Thanks a lot.


Why HashMap is overriding existing string key value

String abc = "abc"; String abc2 = new String("abc"); System.out.println(abc == abc2); //false Map<String, Integer> map = new HashMap<String, Integer>(); map.put(abc, 2); System.out.println("map.get(abc)" + map.get("abc")); //2 map.put(abc2, 1234); System.out.println("map.get(abc)" + map.get("abc")); //1234   If abc and abc2 are not equal then why Hashmap is overriding values?


How can I set the keyboard and language in Android, and how can I add more languages to the device?


Views indicator inaccurate, shows one views on question with two close votes

Two close votes and only one person has viewed the question?    How did this happen?


Need to know if transit visa is required to change the flight in US

Hi I am travelling from india to canada I have a vaild canada visa  The flight which i booked layover in newyork for 5hrs  Should I take a transit visa ?


How does the Cleric's Blessings of Knowledge feature interact with the rules for gaining proficiency when already proficient in a skill?

Scenario:  I am a level 1 Half-Elf Monk, using a combination of my Monk starting skill proficiencies and Skill Versatility racial features to start with proficiency in Arcana, History, Religion, and Nature.   Upon hitting character level 2, I decide that with where I am in the plot at the time, it would make sense to multiclass into Cleric (and I have the proper prerequisites to do so)- this multiclass is not a preplanned decision made at character creation time.  I pick the Knowledge domain, which lets me pick two skills from Arcana, History, Nature, or Religion to become proficient in as part of the Blessings of Knowledge feature. My proficiency bonus is doubled for any ability check I make that uses either of the chosen skills I became proficient in.   By RAW, what skills can I ultimately gain proficiency in, and what skills get the doubled proficiency benefit of Blessings of Knowledge?  The rules for gaining proficiency in the same skill or tool from more than one source are as follows, according to PHB p.125:     If a character would gain the same proficiency from two different sources, he or she can choose a different proficiency of the same kind (skill or tool) instead.   I can see a few different ways to rule this depending on one's interpretation:   The above citation only applies to gaining proficiencies from backgrounds as it's in the "Backgrounds" section, despite the general language of "two different sources". As a result, I gain no proficiencies. I can still choose two of the listed skills to gain doubled proficiency bonuses. The above citation applies. As a result, I still have to choose two out of Arcana, History, Nature, or Religion, but when that choice goes to give me proficiency in a skill I already have, I can then choose any other skill to gain proficiency in. Then, either:   The chosen skills out of Arcana, History, Nature, or Religion get the doubled proficiency bonus. The 'final' skills I newly gain proficiency in do not. Only the 'final' skills I newly gain proficiency in get the doubled proficiency bonus.    Are any of the above interpretations correct?


Choose to not show specific advertisements

I spend a fair amount of time at work on SO, whether it's trying to find questions I can answer, asking my own, or searching for other topics that can help me.  I have a concern with the advertisements for careers.stackoverflow being on my webpage constantly. Because people walk by my desk and I don't want them to think I'm on a job search site. No one's said anything about it and it doesn't make me use the site less, I'd just would prefer it to not show, lest co-workers start getting suspicious.    I have no problem with advertising; obviously it makes SO money. So I don't want to use an adblocker. I know this is similar to  but the difference here is that the careers ad is an internal ad and not one that is being paid for by an outside source.  Can a feature be added to disable specific internal ads or generally reduce internal ads in place of more outside ads?   Edit And then I realized I have no idea of the business practices of the SE network and whether or not there is money changing hands between sites, but I'll assume the simple case that they are all the same


Checking if a file contains number that the user has entered (java)

I have a .txt file in here "C:\failass.txt". It contains the following info:  AA051245445454552117989 LT647044001231465456 LT517044077788877777 LT227044077788877777 CC051245445454552117989   I have found a code which scans if the user input matches the info contained in the file:  package ibanas;  import java.util.Scanner; import java.io.File; import java.io.FileNotFoundException; import java.io.IOException; import java.util.Scanner;  public class ReadFromFile {  public static void main(String[] args) throws IOException {     Scanner myScanner = new Scanner(System.in);     System.out.println("What number would you like to check for?");     String number = myScanner.nextLine();     if(isFound(number)){         System.out.println("The number "+number+ " is there");     }else{         System.out.println("The number "+number+ " doesn't exist");     } }  public static boolean isFound(String number) {      Scanner sc = new   Scanner(ReadFromFile.class.getResourceAsStream("C:\failass.txt"));     String word="";     while (sc.hasNextLine()) {         word = sc.next();          if (word.equals(number.trim())) {              return true;         }     }     return false; } }   But when i enter (for example) this line AA051245445454552117989 it gives me the following error:  What number would you like to check for? AA051245445454552117989 Exception in thread "main" java.lang.NullPointerException at java.io.Reader.<init>(Unknown Source) at java.io.InputStreamReader.<init>(Unknown Source) at java.util.Scanner.<init>(Unknown Source) at ibanas.ReadFromFile.isFound(ReadFromFile.java:24) at ibanas.ReadFromFile.main(ReadFromFile.java:15)   Thanks for any advice :)


How do I install Unity Desktop Environment in Budgie?

I'm currently running the Budgie desktop and would like to try the Unity desktop. How do I install it and change to it?


I live in London and I have been issued a Schengen multiple entry Visa from The Italian Consulate from 18 Aug to 1 Oct. My Holiday to Italy is from 18Aug to 23 Aug. Thereafter I will return to London.   In september I want to visit other countries in Schengen Area like France, Switzerland etc. But this time I will not be going to Italy. Will this be a problem with Port of Entry?


Variables non-significant in univariate analysis but significant in multivariate analysis?

I am running Cox regressions on a data set and I have encountered a situation where two of the variables are non-significant in univariate analysis but become significant in the following multivariate analysis. To exemplify the situation, I am investigating variables A, B and C, which are all continuous variables. For A and B, higher values are expected to increase the hazard ratio. For C, lower values are expected to increase the hazard ratio. In univariate analysis, regressions are performed individually for A, B and C with none of them being significant. However, in the following multivariate analysis, when A, B and C are all included in the model together, A and C suddenly becomes significant? I am not quite sure on how to interpret this and I would be very interested in learning the reasons how this can happen—both generally and in the above example? I have tried to look it up and the explanations range from suppression to the data being sampled poorly, so any input on how to approach this would be very welcome.


SQL Server Pivot Multiple Column and Value

I have a sample table attendance look like this :  PERIOD  EMPL_NMBR   EMPL_NAME           DRPT     DAYX    [IN ]    [OUT] 201603  00001       John                QA       01      08:00    17:00 201603  00001       John                QA       02      08:00    17:00 201603  00001       John                QA       03      201603  00001       John                QA       04      08:00    17:00 201603  00001       Susan               SALES    01      08:00    17:00 201603  00001       Susan               SALES    02      201603  00001       Susan               SALES    03      08:00    17:00 201603  00001       Susan               SALES    04        I'd like to display the data from that table like this:  PERIOD     EMPL_NMBR     EMPL_NAME      1           2            3             4                                    [IN]  [OUT]  [IN]  [OUT]  [IN]  [OUT]   [IN]  [OUT] 201603     00001         John     08:00  17:00  08:00  17:00  -      -     08:00  17:00 201603     00002         Susan    08:00  17:00   -      -    08:00  17:00    -      -   I can successfully pivot it using a single column and single value dynamically, but I get confused when I try to pivot multiple columns and values dynamically.  Can anyone help me?


I'm having problems with texturing a model in cycles (blender 2.72b). I downloaded the model and it comes with 3 tga files per section. see image below for the hair for example  I render in cycles. I search the forums, but i still can't get the transparency right. How do I set this up with nodes?  Many thanks in advance!


how to put some characters between others to make price value userfriendly?

I have a string like price:  string price= "5000000";   but i want to know, how can i change it (in c#) to something like this:  "5,000,000"   because it's very better and user friendly.


I noticed this now a few times and it slowly begins to be anoying.  My way of handling deathclaw attacks went to be just let them go through room by room untill they are dead, since rearranging the infrastructure of sending my strongest dwellers with them is... fiddly.  But as the title says:  Sometimes after revieving the victims of an Deathclaw attack they appear to lay down work on random occassion and just go into coffe break. Since I noticed this I'm observing this behavior and wasn't able to catch them doing so. But it appears to happen in direct connection with the event of dying. But the change in working state appears to happen while the app itself is closed (can't confirm this so far.)  This is actually anoying since they appear to start working again but on i.e. the next day I have to find them again and reassign them to their jobs. but if there are some times 5 dwellers just idling arround its hard to figure out what the job was for each of them.  Is this issue known? Is it even an issue or just the result of a feature I'm not aware of/missunderstanding?  Or is it just because Dwellers demand some special leave after dying?


Extremely slow display of JPEGs and other images in 15.10

[This question has been marked as a duplicate (relating to graphics drivers) but it is not. I have . The problem is triggered by suspending and resuming VMware Workstation.]  Since upgrading to Kubuntu 15.10 (from 14.04 LTS), some programs that display JPEG and PNG files are taking a very long time to run. For example, a 1.5 MB JPEG, which used to display instantly, now takes over 10 seconds to appear on screen. A 2 MB file takes over 20 seconds.  This is on a very fast computer (12 cores, SSD, 32 GB RAM).  Affected programs include:   display (from Imagemagick 6.8.9-9) eog (GNOME Image Viewer 3.16.3) geeqie (version 1.2)   Unaffected programs include:   The Gimp   Chrome (if I type "chrome IMG_3123.JPG")   Example file:  $ ls -l IMG_3123.JPG -rw-r--r-- 1 smith users 1562373 Sep 12 07:14 IMG_3123.JPG   When I run:  $ display IMG_3123.JPG   it takes 10 seconds to show the image.  Under Kubuntu 14.04, it took less than 1 second.  Note: If I reboot, the problem goes away.  Then it returns sometime later.  I am also seeing  like Chrome. It makes me wonder if this problem could be related to graphics drivers? Or some common library?  My graphics information is:  $ sudo lshw -class display   *-display                       description: VGA compatible controller        product: GK107 [GeForce GT 640]        vendor: NVIDIA Corporation        physical id: 0        bus info: pci@0000:01:00.0        version: a1        width: 64 bits        clock: 33MHz        capabilities: pm msi pciexpress vga_controller bus_master cap_list rom        configuration: driver=nouveau latency=0        resources: irq:46 memory:fa000000-faffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:e000(size=128) memory:fb000000-fb07ffff   So I am running the nouveau driver, but I am pretty sure I was running nouveau in Kubuntu 14.04 as well.  Update:  I tried  and rebooting. I saw a new error on boot:  Kubuntu 15.10 . . . . EDAC sbridge: ECC is disabled. Aborting. EDAC sbridge: Couldn't find mci handler   When the reboot completed, I could not log in using the graphical login screen. I'd enter my password and immediately be returned to the login screen. Error in /var/log/syslog said:  Nov 23 15:35:04 myhost systemd[1]: Started Session c4 of user smith. Nov 23 15:35:04 myhost console-kit-daemon[2945]: (process:10614): GLib-CRITICAL **: g_slice_set_config: assertion 'sys_page_size == 0' failed Nov 23 15:35:04 myhost gdm[2819]: GdmDisplay: display lasted 0.044295 seconds Nov 23 15:35:04 myhost console-kit-daemon[2945]: (process:10623): GLib-CRITICAL **: g_slice_set_config: assertion 'sys_page_size == 0' failed Nov 23 15:35:04 myhost console-kit-daemon[2945]: GLib-CRITICAL: Source ID 121 was not found when attempting to remove it Nov 23 15:35:08 myhost gnome-session[3177]: GLib-GObject-CRITICAL: g_object_unref: assertion 'G_IS_OBJECT (object)' failed Nov 23 15:35:09 myhost gnome-session[3177]: gnome-session[3177]: GLib-GObject-CRITICAL: g_object_unref: assertion 'G_IS_OBJECT (object)' failed   So I  and rebooted, and the system went back to normal.  I tried installing other versions of the nvidia drivers but the same problem occured, so I still have no solution.  Update 2:  OK, this is weird. The problem happened again, with JPEGs taking 20 seconds to open. I closed VMware Workstation (12.0.1), which is running a couple of Windows VMs as guests, and the problem instantly stopped. It's not memory-related, because I had 28GB RAM free even before closing VMware.


I used to have 2TB of iCloud storage then for several months of not paying, I was downgraded to 5GB free storage.  What happens to the data I previously had?  Will it get deleted?


How does the Hellfire Warlock's hellfire blast function?

I'm trying to properly understand the      Hellfire Blast (Sp): Whenever you use your eldritch blast ability, you can change your eldritch blast into a hellfire blast. A hellfire blast deals your normal eldritch blast damage plus an extra 2d6 points of damage per class level. If your blast hits multiple targets (for example, the eldritch chain or eldritch cone blast shape invocations), each target takes the extra damage. This damage is not fire damage. Hellfire burns hotter than any normal fire, as described in the sidebar on page 119.      Each time you use this ability, you take 1 point of Constitution damage. Because the diabolical forces behind the power of hellfire demand part of your essence in exchange for this granted power, if you do not have a Constitution score or are somehow immune to Constitution damage, you cannot use this ability.   1. Is all the damage from a hellfire blast considered hellfire or only the extra damage?      Eldritch Essence Invocations      Some of a warlock's invocations, such as frightful blast, modify the damage or other effects of the warlock's eldritch blast. These are called eldritch essence invocations. Unless noted otherwise, eldritch blasts modified by eldritch essence invocations deal damage normally in addition to imparting the effects described in the invocation description.      A warlock can apply only one eldritch essence invocation to a single eldritch blast, choosing from any of the eldritch essence invocations that he knows. When a warlock applies an eldritch essence invocation to his eldritch blast, the spell level equivalent of the modified blast is equal to the spell-level of the eldritch blast or of the eldritch essence invocation, whichever is higher. If a warlock targets a creature with an eldritch essence blast that has immunity to the invocation's effect, it still takes the damage from the blast normally (provided it isn't also immune to the eldritch blast).      A warlock can apply an eldritch essence invocation and a blast shape invocation (see below) to the same blast. When a warlock uses both kinds of invocations to alter an eldritch blast, the spell level equivalent is equal to the spell level of the eldritch blast, the level of the eldritch essence invocation, or the level of the blast shape invocation, whichever is higher. (Complete Arcane, pp. 8-9)   -     Vitriolic Blast      This eldritch essence invocation allows you to change your eldritch blast into a vitriolic blast. A vitriolic blast deals acid damage, and it is formed from conjured acid, making it different from other eldritch essences because it ignores spell resistance. Creatures struck by a vitriolic blast automatically take an extra 2d6 points of acid damage on following rounds. This acid damage persists for 1 round per five class levels you have. For example, a 15th-level warlock deals 2d6 points of acid damage per round for 3 rounds after the initial vitriolic blast attack. (Complete Arcane, p. 136)   2. Can a hellfire blast also be a vitriolic blast? If it can, is it hellfire or acid? If it's hellfire does it still ignore spell resistance and do an extra 2d6 points of damage on following rounds"?  Here is an  It ends on post #36.


How to check whether a given $W(x,p)$ represents a Wigner function of a physical state?

For simplicity let us consider one-dimensional quantum-mechanical systems only. Given any state $\rho\in\mathcal{B}(\mathcal{H})$ and its Wigner function $W_\rho(x,p)$, there are several properties it always satisfies,   it is real-valued and bounded in absolute value by $2/\hbar$ from above, its marginals are well-behaved probability distributions, its overlap $\int W_\rho(x,p) W_\sigma(x,p) \mathrm{d}x\mathrm{d}p$ with the Wigner function of any other state $\sigma$ is nonnegative.   Given an arbitrary function $W(x,p)$, we can reconstruct a state $\rho$ it corresponds to iff all of these conditions are met using the Weyl transform. If some properties are not satisfied, the resulting operator will be unphysical—non-Hermitian, unnormalized or non-positive. The question is how to check the conditions prior to the calculation.  The first two are usually fairly easy to check but the latter involves going through all states of the system. Even if we restrict ourselves to pure states, this still iterates over all rays in an infinite-dimensional linear vector space and is as such usually done finding a proof tailored to the specific case. Is there a simpler (algorithmic) condition which can replace the third bullet above and implies its validity?


Which is correct in this example? Who or whom? (example upon which my friends and two professional editors could not come to an agreement)

I know this question has been posed many times already, but I've had several people (some even professional editors) who cannot decide on the correct form in this sentence.     Three men, one demon, one minority—on a quest to kill the guy who/whom   Domino’s parents love more than him.   Please tell me which is correct. Who or whom?  I myself am unsure (regardless of other answers) in this situation, because a few people and both my developmental and copy editor have differing opinions, so I have no idea which one is right, since both have their own opinions and arguments for this. One editor says "who" is correct here because the person in question is the subject in this sentence (although I'm not sure whether they are right or wrong about that), but the other editor said I need to follow the "he/him" rule. Thus, I don't know which rule to follow.


If you have a few meetings with a professor to discuss a paper, but they do not do any actual writing, is this sufficient to justify authorship?

Earlier this year I started writing my first article with a former professor of mine. The article is almost done, but until now he hasn't written a single sentence or provided any data. It has been all my work.  We have met about 10 times where each meeting lasted about 90 minutes to discuss the progress of the article, and I have to recognize that during these meetings his advice shaped some of my ideas , especially regarding the research question. I know he has spent his time in this work, but I don't think that qualifies as authorship on the article, and I'm not sure what to do about this. I appreciate any advice you can give me on how to act on this issue.  So in general:  If a professor meets with you a few times to assist you in writing a paper but does not do any actual writing, is this sufficient to justify him being an author?


How to show render-stamp for arbitrary values?

Is it possible to take arbitrary properties and display them in the render stamp as some other software do.   (Click the image for larger version)


How to type half Hindi character with Hindi (Bolnagri) layout?

I'm using Hindi (Bolnagri) layout to type in Hindi. I'm typing in Hindi for first time.  My problem is, I want to type स्वाद. How do I type that half स?    EDIT 1:  How to type औ with this layout?    EDIT 2:  How to type र्श as in आदर्श?


I will turn the AC on vs i am going to turn the AC on

I am reviewing tenses right now: there are some really good worksheets online. It is often confusing to know what tense you have to apply, especially while talking. Anyhow, what's confusing me now is the really subtle difference between "will" and "going to".     A: I can't hear the television!   B: I (turn) will turn it up so you can hear it.      Ted: It is so hot in here!   Sarah: I (turn) will turn the air-conditioning on.   Both times "will" future is used, but i wonder why not " going to "? Because from my understanding is, that "going to" is used when you plan to do sth, and "will" for a prediction or an assumption.  Isn't it sure that you turn it on, same as in "I am going to college after i graduate "?  Also, could you say ... turn on the aircon or does it have to be.... turn the aircon on? Where do prepositions that come with a verb go?


Prove that there are two subsets of any cardinality-10 subsets of $\{1,2\dots,106\}$ that sum to the same number

Let  $$S_X = \sum_{x\in X}x$$  and  $$Z = \{1,2,3,...,106\}$$  Prove that, for all subsets $A$ of $Z$ of cardinality $10$, there exist distinct subsets $B,C$ of $A$ such that $S_B=S_C$. Then prove that there exist disjoint subsets $B$ and $C$ of $A$ with that property.  (I have no idea why the problem decided to choose that set instead of, say, $\mathbf N\backslash\{0\}$, but it makes me think it might start failing for larger numbers.)


Change RDP Port of Windows 2012 R2 server running in amazon AWS

How do I change the RDP port number of Windows 2012 R2 server running in Amazon AWS? I could change the port number by going here:  HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\TerminalServer\WinStations\RDP-Tcp\PortNumber   but then could not RDP into server even after changing the inbound rules of security group.


Coherence of waves - phase difference constant OR frequency the same?

Wikipedia states,  "In physics, two wave sources are perfectly coherent if their frequency and waveform are identical and their phase difference is constant"  In an A Level Physics Marking Scheme, students are often asked to define coherence. The mark is scored for saying coherence is when the waves 'have a constant / fixed phase difference' We ignore and give no marks for a comment that says 'the frequency / wavelength is the same'. In my head, the frequency of two waves is the same if and only if there is a constant phase difference between the waves. So does anyone have an idea why the mark scheme classes 'the frequency is the same' as insufficient?


Update Manager bug: Encountered a section with no Package: header

I tried to do an update to my system (12.04 LTA 64bit, on ACER aspire V5) got this:     Could not initialize the package information      An unresolvable problem occurred while initializing the package information.      Please report this bug against the 'update-manager' package and include the following error message:  E:Encountered a section with no Package: header, E:Problem with MergeList /var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_precise-security_main_binary-i386_Packages, E:The package lists or status file could not be parsed or opened.    Now What?


I have just upgraded to 2.8 and upon opening up a project I was working on in the old version I find that only the object I last had active is shown.  Alt H is not revealing other objects event though they are in the outliner. In fact according the to the outliner, all the objects should be shown, but aren't  I am sure there is some small trick here. Can someone please help this noob out  super thanks


Unable to find videos cache for youtube videos in chrome

I have watched a video on youtube, I didn't close the browser window and it is buffered. I can watch that video anytime, without connecting to internet, as it is completely buffered. But I am not able to find the local cache for it, I checked the default folder of cache for my browser(chrome), which is: %AppData% Local\Google\Chrome\User Data\Default\Cache, but videos is not there. However it must be there somewhere in my local system as I am able to watch it again and again without connecting to internet. I used to get those previously, but something happen either it is saving in some other folder or what.  does anyone has any idea?


The MAC size is reduced to 80 bits in  , which says "forging of MAC values cannot be done off-line: in TLS, a single failed MAC guess will cause the immediate termination of the TLS session."  Question 1 (main question): So can I reduce MAC size to something even smaller, say 32 bits?  Question 2: The truncated_hmac extension does not effect AEAD. Can I reduce the tag's size in AEAD, e.g. GCM or CHACHA-POLY?


Why do some characters call the Machine "she"?

On Person of Interest, most people on Team Machine refer to it as "she". To me, that's sort of clear for Root, not so clear for Finch and even less clear for others. Why do they do that?  P.S. I don't recall perfectly, but Samaritan is mostly called "it" and not "he". But should it be a "he" in contrast to the Machine?


Tool for quickly backup and restore a table

Is there a tool for quickly backup and restore a table's data, preferably to a csv file?  It would be best if I could do it using batch. Run a .cmd file and data is backed up into a file with datetime name. And anytime needed I can just run another .cmd file to restore a file into the table.


Prove that $r_1s_1, r_2s_2, ..., r_{p-1}s_{p-1}$ is not a reduced residue system modulo p.

If $r_1, ... r_{p-1}$ and $s_1, ... s_{p-1}$ are two reduced residue systems modulo an odd prime p, prove that $r_1s_1, r_2s_2, ..., r_{p-1}s_{p-1}$ is not a reduced residue system modulo p.  don't know where to start, any help appreciated!


Coefficient estimates from $(X'X)^{-1}, X'y$ and $\widehat{u'}\widehat{u}$

How can one calculate the standard scores of the coefficient estimates given $(X'X)^{-1}, X'y$ and $\widehat{u'}\widehat{u}$. Where $(X'X)^{-1}$ is a $n \times n$ matrix, $X'y$  is a $n \times 1$ matrix, and $\widehat{u'}\widehat{u}$ is a scalar.


UEFI: Installing Ubuntu along with Windows 10

I want Ubuntu to run as second OS on my Laptop which has Windows 10 preinstalled. I had a Kubuntu version running but unfortunately Windows 10 was installed with UEFI while I installed the Kubuntu in lagacy BIOS.  That worked but it was quite anoying to switch operating systems (also Kubuntu had huge problems with my touchpad). So I installed Ubuntu in UEFI mode on the partitions the Kubuntu was once installed on. I expected my laptop to let my choose between Windows and Ubuntu the next time I restart but Windows starts automatically.   The installation was without errors and Windows quickstart is disabled. What can I do to make the Windows Bootmanager recognize Ubuntu?  I have an Acer Aspire V5-591G-54PC


i3wm: How to move windows between monitors?

In a multiple monitor set-up with i3, how do you move windows between monitors using keybindings?


Accessing Nested Lists that are part of an object (class)

Okay so the code below is example code i have made to illustrate my problem, i'm new to python, I'm using 2.7 and i have searched quite a lot with no success. The code all works except for one issue.  My problem is the object (Test) attribute Nested_list's that is printed at the end shows that the for loop that adds +1 to the first item in each list instead adds +1 to the first item in all 3 lists. i know the method i'm using would work on a normal list but for objects it's not quite right.  class Test(object):      def __init__(self):         self.nested_lists = [[0]*10]*3  object_holder = [[]]*30  for x in xrange(0, 30):     object_holder[x] = Test()  for objects in xrange(0, 30):     for lists in xrange(0, 3):         for items in xrange(0, 10):             object_holder[objects].nested_lists[lists][items] += 1  object_holder[1].nested_lists[0][8] += 5 object_holder[1].nested_lists[2][5] += 12  print object_holder[1].nested_lists print object_holder[1].nested_lists[0] print object_holder[1].nested_lists[0][8] print object_holder[1].nested_lists[2][5]  print object_holder[2].nested_lists print object_holder[2].nested_lists[0] print object_holder[2].nested_lists[0][8] print object_holder[2].nested_lists[2][5]   result  [[3, 3, 3, 3, 3, 15, 3, 3, 8, 3], [3, 3, 3, 3, 3, 15, 3, 3, 8, 3], [3, 3, 3, 3, 3, 15, 3, 3, 8, 3]]  [3, 3, 3, 3, 3, 15, 3, 3, 8, 3]  8 15  [[3, 3, 3, 3, 3, 3, 3, 3, 3, 3], [3, 3, 3, 3, 3, 3, 3, 3, 3, 3], [3, 3, 3, 3, 3, 3, 3, 3, 3, 3]]  [3, 3, 3, 3, 3, 3, 3, 3, 3, 3]  3 3   why is this? When it seems I can use print to target individual list's and items?? I have looked at getattr and setattr but i cant find anything on targeting nested lists with this method.   This shows when I try to target a specific item that it is possible, but for some reason which list I target is not definable? The result I was expecting would be every item equalling 1, except the individual items I added 5 and 12 to. Any help would be greatly appreciated


Is Innate Spellcasting counterspellable?

On p.85 of Xanathar’s Guide to Everything, there’s a section clarifying that you need to perceive a spell being cast (by either a verbal, somatic or material component) in order to counterspell it.  It then goes on saying this :     If the need for a spell’s components has been removed by a special ability, such as the sorcerer’s Subtle Spell feature or the Innate Spellcasting trait possessed by many creatures, the casting of the spell is imperceptible.   The thing is that many monsters’ Innate spellcasting specify that only material components are discarded (not verbal or somatic). So I am not sure whether you can actually counterspell innate spellcasting when the stat block only mentions removing material components.  There seems to be  supporting that such spells could be counterspelled (although it is confusing a bit).  It basically comes down to whether the above quote’s “many creatures” refers to all creatures with innate spellcasting, or only those that forgo all spell components to innanely cast. So, which is it ?


Command + C does not always work from the first try in Microsoft Word (Office 2011)

I have no idea why COMMAND + C doesn't always register from the first time. I sometimes try to copy something off Word, but I have to press COMMAND + C more than once for it to register, otherwise COMMAND + C just prints what was copied in clipboard before. This becomes very irritating.  However I realised that if I press COMMAND then pause for a second, THEN press C, the command always registers.  EDIT  I noticed that when I select any text in word, it takes about a second for the Cut and Copy buttons to be highlighted (otherwise they're greyed out). And THIS has direct effect on this problem. Only when they are not greyed out anymore can I copy and paste using keyboard shortcuts correctly.  What is happening ?


Biblatex (biber) sortlocale=se sorting Å as F

I can't get the swedish character Å to sort correctly. (It should be A-ZÅÄÖ), I have attached code that should display the issue: Edit: I am using sharelatex.com, and would prefer if it was solvable within that ecosystem.  \documentclass{article} \usepackage[utf8]{inputenc} \usepackage[backend=biber,style=authoryear,maxbibnames=99,maxcitenames=3,sorting = nyt,sortlocale=se]{biblatex} \addbibresource{references.bib} \begin{document} \section{Introduction} Hello \parencite{Ahlstrom} \parencite{gillham2008} \parencite{eupopulation} \printbibliography  \end{document}   References.bib:  @online{eupopulation,     author = "{Eurostat}",     title = "Population structure and ageing",     date = "2018-01-12",     addendum ="(Hämtad 2018-02-04)"  } @incollection{Ahlstrom,     author = "Pär Åhlström",     title = "Human Relations: Elton Mayo \& the Hawthorne Investigations",     booktitle = "Industriell Verksamhetsutveckling",     publisher = "Göteborg: Chalmers tekniska högskola",     editor = "Magnus Persson",     year = "2016",     keywords  = "hawthorne",     pages = "71-74", } @book{gillham2008,     author = "Bill Gillham",     title = "Forskningsintervjun: Tekniker och genomförande",     translator = "Emily Jamison Gromark",     shorttitle = "Forskningsintervjun",     publisher = "Studentlitteratur",     year = "2004",     keywords = "Forskningsintervjun",     ISBN = "978-91-44-04012-7" }


I have the following in my httpd.conf file  NameVirtualHost *:80  <IfModule mod_vhost_alias.c>   <VirtualHost *:80>     ServerAlias *     UseCanonicalName Off     LogFormat "%V %h %l %u %t \"%r\" %s %b" vcommon     CustomLog /var/log/httpd/access_log vcommon     VirtualDocumentRoot /web-data/vhosts/%0/httpdocs     VirtualScriptAlias  /web-data/vhosts/%0/httpdocs   </VirtualHost> </IfModule>   This works great for dynamic hosting. However, I can't figure out how to make https requests work the same way. What do I need to add to this so that https and http for the same domain request get sent to the same folder?


Can I delete a file from being shown in the 'recents' area of the Files iOS app?

I am trying to remove some files out of the 'recents' view of the files iOS app without actually deleting the file.   My 'recents' list is currently too long, for this view to be of any help for me at this point. Ideally, I can curate individual items that aren't relevant and keep the rest of the list, but if needed - can I just purge all recents and start cleanly?


Can anyone explain to me the advantages of defining an anonymous function and assigning to a variable, contrary to defining by function name. Ie.  var add = function(a, b) { return a+b}; var result = add(1, 2);   Contrary to  function add(a, b) { return a+b }; var result = add(1, 2);   BTW I'm new to javascript but done a lot of C-style coding.  Best regards Ben


Hard sci-fi story: man escapes telepathic creatures by imagining himself in a fire

A ship crashes on a planet. A man survives.  Short version, all the species (no intelligent species) have developed Telepathy.  He is hunted and finally comes to the conclusion that he is being hunted telepathically.  After some time, he gets the idea that the animals are like all animals and fear fire.  So he focuses very intently on there being one heck of a big fire with him at the center of it and everything runs away.  He is then picked up by a rescue ship and they would have sworn he was in the middle of a fire.


Should you perform feature scaling/mean normalization when predicting with a model?

Should you also perform feature scaling/mean normalization when predicting with a model, that was trained and tested on with feature scaling/mean normalization?


I am setting up my VPS with Ubuntu 20.04 installed, that I am using to host my personal website. I am editing /etc/apache2/apache2.conf to allow Apache to access my website directory (according to ), by adding: <Directory /path/to/website/directory/>         Options Indexes FollowSymLinks         AllowOverride None         Require all granted </Directory>  After this edit, Apache won't restart and I get the following error message when executing service apache2 reload: Job for apache2.service failed. See "systemctl status apache2.service" and "journalctl -xe" for details.  journalctl -xe indicates: Mar 29 07:54:18 vps-b3576e37 sudo[41093]: pam_unix(sudo:auth): Couldn't open /etc/securetty: No such file or directory  I have tried adding a /etc/securetty file with the contents given in , and I have tried copying the example file cp /usr/share/doc/util-linux/examples/securetty /etc/securetty, but the error remains. If I remove my website's directory in /etc/apache2/apache2.conf, Apache is able to restart. I did not have this issue on my previous Ubuntu 18.04 VPS. Is there something wrong with the /etc/securetty file which I created? Or is there a better fix?


I would like to know how to round off numbers in an array

I cannot find any pattern rounding off doubles in an array. I am trying to make a program that will input a double like grades,money etc., and round it off in a whole number.


I have following list:  cnames = [" green ", " blue ", " yellow ", " gray ", " pink ", " orange ", "purple ", " red ", "brown "]   How do I get 6 random and unique indexes representing a number between 0    and      len(cnames)     from that list?


Disk intermittently goes to 100% actviity - system pauses

Windows 8.1 system.   Sometimes the disk suddenly go 100% highest active time for 1 or 2 seconds, and at the same time CPU usage goes down.   During these period, screen processing does not work any more. Processing returns to normal when high disk activity goes down.  How can I fix it?


Is having 3 whole eggs at breakfast harmful?

Last couple of day I have been having 3 whole eggs scrambled with around 2 tea spoon soybean oil in breakfast. Some friends of mine told me having 3 whole eggs is harmful for my health. I understand that it may increase my cholesterol. But in my opinion, eggs are fulled with protein and other important nutrients ( and easy to cook :P ). Do eggs raise cholesterol levels?


Add data from a REGION FeatureCollection to my polygons FeatureCollection

I have generated a FeatureCollection of polygons and calculated the centroid and added it. I now want to pull in some data from FAO/GAUL/2015/level2 dataset with fields such as ADM2_CODE etc. This can be just the centroid.  How do I get data out of one FeatureCollection and add it to mine?  var fromList = ee.FeatureCollection("FAO/GAUL/2015/level2");  var filter = ee.Filter.inList('ADM2_NAME', ['Gwent']); var filteredArea = fromList.filter(filter);  Map.setCenter(1.1, 51.5, 8); Map.addLayer(filteredArea, {}, 'Regions');  var gfc2018= ee.Image('UMD/hansen/global_forest_change_2018_v1_6').clip(filteredArea);  var lossImage = gfc2018.select(['lossyear']).gte(7); var lossBand = lossImage.and(gfc2018.select(['lossyear']).lte(20)); var zones = lossBand.updateMask(lossBand.neq(0));  // Add the loss layer in red. Map.addLayer(lossImage.updateMask(lossBand),             {palette: ['FF0000']}, 'Loss 2007 onwards');  var area_threshold = 300; // about 30 hectares?  // Define whole county as a region var geom = filteredArea.geometry();  // Convert the zones of the forest loss areas to vectors. var vectors = zones.addBands(zones).reduceToVectors({   geometry: geom,   crs: lossBand.projection(),   scale: 30,   geometryType: 'polygon',   eightConnected: true,   labelProperty: 'zone',   reducer: ee.Reducer.count() }).filterMetadata("count","greater_than", area_threshold);  // Make a display image for the vectors, add it to the map. var display = ee.Image(0).updateMask(0).paint(vectors, '000000', 1); Map.addLayer(display, {palette: '000000'}, 'vectors');  var SRTM = ee.Image("USGS/SRTMGL1_003"); // exampleelevation image  var slope = ee.Terrain.slope(SRTM);  // add min, max and mean elevation of each geometry var reducers = ee.Reducer.median()                 .combine(ee.Reducer.min(), 'Elevation', true)                 .combine(ee.Reducer.max(), 'Elevation', true)                 .combine(ee.Reducer.mean(), 'Elevation', true);  vectors = SRTM.reduceRegions(vectors, reducers, 30);  // This function computes the feature's geometry area and adds it as a property. var addCentroid = function(feature) {   return feature.set({CentralPoint: feature.geometry().centroid(10)}); };  // Map the area getting function over the FeatureCollection. var CPAdded = vectors.map(addCentroid);  // Get Admin Districts var AreaName = filteredArea.aggregate_first("ADM2_CODE")  // How can I add the ADM2_CODE or any of the fields to my featurecollection? It can be just for the central point which I have calculated?  // Export the FeatureCollection to a CSV file. Export.table.toDrive({   collection: CPAdded,   description: 'ForestPlus',   fileFormat: 'CSV' });


How to change the size of Modal in Lightning

How can I update the size of the modal to fit only the size of the text inside it.  This is what it currently looks like,   This is the my code for this     <aura:attribute name="recordId" type="Id"/> <aura:attribute name="message" type="String" default=""/>  <aura:handler event="aura:waiting" action="{!c.waiting}"/> <aura:handler event="aura:doneWaiting" action="{!c.doneWaiting}"/> <aura:handler name="init" value="{!this}" action="{!c.doInit}"/>  <aura:attribute name="isOpen" type="boolean" default="True"/>  <aura:if isTrue="{!v.isOpen}">

Submit

                     <form id="form">

                                          Sending...

                                     <ui:outputText value="{!v.message}"/>

                     </form>

                      <lightning:button variant="neutral"                                label="Close"                               onclick="{! c.closeModel }"                               title="Close"                               />

 </aura:if>      Since I used force:lightningQuickActionWithoutHeader to remove the header and created my own, I used modal to replicate the feel of using force:lightningQuickAction but I can't seem to fit the content to the modal.  I need your help guys, Thanks


Diferrence between Uxterm, Xterm and terminal?

Is there a difference in authority between the Xterm and the Ubuntu terminal? I'm a beginner to Ubuntu and I'm worried if I used the Xterm that I somehow have root privileges and I can harm the PC?


I'd like to create a custom scope that searches and returns results from an online source for personal use.  Is this possible? And if so, how?


Can someone clearly explain the tasks of each pin in a plug. Is there a difference between one phase and three phase plugs? Does the electricity enters our home from line connection and goes back to the generator from neutral connection? The third one is connected to ground to protect us but is it really necessary because some plugs only have two pins.


High-side switch 24V 6mA control by Arduino

I would like to ask for best solution for my issue.  I need high side switch for 24VDC 6mA (it is enable signal for a device). This device I want to control by Arduino (input 5 V 20mA).  What is the best solutions for this low current?  I tried to use Sziklai pair, but PNP transistor is still open. I don't know how to calculate resistors between NPN and PNP :-(. Do I have to use a sziklai pair or is there something else?         – Schematic created using   Thank you so much  Lukas


Let $a,b,c$ be non-zero integers . Let $(x,y)$ denote the gcd and $[x,y]$ denote the lcm of two non-zero integers . Then is it true that $ (a,[b,c])=[(a,b),(a,c)]$ ?


Calculating a composite index in PCA using several principal components

I have a question I was hoping this group could help answer or provide more insight on.   I'm looking to construct an overall composite index for counties. Really a simplified version of the County Health Rankings    I have 49 county-level health outcome variables such as prevalences of smoking, various cancers, obesity, I have U.S. Census commute, fruit veggie intake, and I have SES poverty/education, and population density data.  I've completed descriptive stats, looked at correlations, conducted principal components analysis using PROC FACTOR in SAS, completed rotation, and have decided upon three PC Factors to include in my analysis that explain about 74% of the variance. Roughly, the factors can be thought of as cancer prevalences, all over disease prevalences(smoking, obesity,physical activity), and SES factors.    My question is as follows: how do I combine these all into one index? Or how do I make separate indices for each? I realize the factors are all uncorrelated but they are all pertinent factors into rating the healthscape of a county which is what I'm trying to index.   In past threads such as this   which references this publication  (pg. 19), the strategy was frowned upon in the comments by @amoeba and @ttnphns. Can anyone elaborate?


A few days ago I started studying classical mechanics and today I'm stuck with the integral formula for work. I didn't take the formula for granted and i tried to understand it, however, the presence of both dt and ds didn't allow me to grasp it deeply  $W=\int m\frac{d\mathbf{v}}{dt}\cdot d\mathbf{s}$  So I tried to elaborate this formula, and I get:  $dW=mvdv$  This means that the infinitesimal work is simply the dv of a body with momentum mv, and is very intuitive.  Why in books the work formula is always presented as $W=\int \mathbf {F}\cdot d\mathbf{s}$ ? Wouldn't be better to explain first of all the momentum and then the fact that an infinitesimal change of energy is $dW=mvdv$ ?


Possible Duplicate:      I need a way to know the name of calling methods in C#.  For instance:    private void doSomething() { // I need to know who is calling me? (method1 or method2).  // do something pursuant to who is calling you? }   private void method1() {  doSomething(); }  private void method2() {  doSomething(); }


"One-size-smaller than the accompanying font size" command

I want to make a subtitle for a chapter, having \Large as the chapter's title font size; so I'd write it as  \documentclass{book} \begin{document} \tableofcontents \chapter{Title \\ {\large Subtitle}} \end{document}   This would make the subtitle's font size look good where the title is, but look horrific in the toc. So I'm asking, is there any kind of command or workaround so that will decrease subtitle's font size by one size, in both occasions? From \Large to \large in the chapter and from \normalsize to \small in the toc.   Thanks in advance


I am currently exploring the training of Neural Networks. I have some toy data and I've trained a NN with 2 hidden layers on it and I get 99 % accuracy on the test set. But the problem is that if I add an additional layer, my training set accuracy drops drastically to around 56 %. Thus I wanted to ask If anybody might know why that might be? Is it likely that I've coded something wrong (however I had no problem going from 1 -> 2 hidden layers), or it could be that if I try to train the a simple set on a very complex model (at least for the set), it could give me such erroneous results.  Thank you very much.


Starting from the nth term to the end of list python

Hello I was wondering how you could do the following in python Suppose we have these lists ["Apples","Pears","Oranges","Grapes"] ["Apples","Pears","Oranges","Grapes","Strawberries"] ["Apples","Pears","Oranges","Pumpkins","Cherries","Lemons"]  And I wanted to extract to extract the 4th element and beyond. So... ["Grapes"] ["Grapes","Strawberries"] ["Pumpkins","Cherries","Lemons"]  The lists will all have more than 3 elements. How would I do this?


I'm looking for custom code to remove fields on user profile like you see in the pictures :  I would also like to replace Gravatar images with simple photos from the media library: