This is from .bashrc file: # If this is an xterm set the title to user@host:dir case &quot;$TERM&quot; in xterm*|rxvt*)     PS1=&quot;\[\e]0;${debian_chroot:+($debian_chroot)}\u@\h: \w\a\]$PS1&quot;     ;; *)     ;; esac  I was wondering what does \[\e]0;${debian_chroot:+($debian_chroot)}\u@\h: \w\a\] do? I know \[...\] are non-printing characters, but what does this actually do?
The default PS1 variable on my machine (Kubuntu 13.10) is this:  \[\e]0;\u@\h: \w\a\]${debian_chroot:+($debian_chroot)}\u@\h:\w\$   I'm looking for a reference for how the $PS1 variable works that, at a minimum, allows me to understand the above PS1 variable.
Simple request, really.  Can we add a detection for the     Please avoid extended discussions in   comments. Would you like to   automatically move this discussion to   chat?   prompt, so that if one of the users in the "extended discussion" has under 20 rep it doesn't appear?  I think a lot of the users this apply to will have low rep and it may take some back and forth to get good info out of them.  New suggestion: how about if a sufficiently high-rep user is clicking on the link, the low-rep user gets a field promotion sufficient to chat? Low-rep users are particularly prone to post questions to lead in this direction of needing to move to chat. Event binding on dynamically created elements? I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off.  This happens on page ready and works just fine.  The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound.  I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option. How to find real world Selenium projects Where can I find sample or real Selenium projects. All the material I can find on github and on internet are basic, and never intermediate or advanced.  How does a real Selenium project look in real life? How can I find sample code? Calculating determinant with different numbers on diagonal and x everywhere else I'm having troubles solving the following determinant:  $$\left|   \begin{array}{cccc}     a_1 &amp; x &amp; \ldots &amp; x \\    x &amp; a_2 &amp; \ldots &amp; \vdots \\     \vdots &amp; \ldots &amp; \ddots &amp; x \\     x &amp; \ldots &amp; x &amp; a_n \\   \end{array} \right|$$  I have tried coming up with recurrent formula, but there's always one lingering row and column. I also tried finding values of x for which determinant is 0, hoping I could get a nice polynomial solution, with no luck.  By subtracting first row from every other I get somewhat nicer result, but there's still that one row/column which I can't solve. If all other columns are added to the first one and then I subtract the first row, then the column doesn't depend on x anymore, but I haven't found 1..n much more useful. Overriding the final destination of the OAuth2.0 flow from a custom OAuth2.0 Auth provider Background:  I have created a custom Auth. Provider in Salesforce to reach out to an authorization server that isn't on the default list of Provider Types. I used  as a good starting point to extend the Auth.AuthProviderPluginClass. Once appropriately added to my org, it then became an option on the list of Provider Types. I was able to create an Auth. Provider using that new provider type and it works to initiate the OAuth2.0 flow. I am appropriately able to get the access token and refresh token from the authorization server.  The Problem:  As it currently stands, we will have users click on a button that will send them to the provided "OAuth-Only Initialization URL" link that was generated when I created the actual Auth. Provider record. The trick is that when the OAuth2.0 flow is completed, the user is redirected back to the Salesforce Setup Home page, and I don't see a good way in the documentation to override the final destination to be something else (like a success page or something).  Question:  Does anyone know of a way to override the final destination of the OAuth2.0 flow from a custom OAuth2.0 Auth provider?    UPDATE: I tried using the startUrl (and also tried retUrl for good measure) as query params, but doing so didn't change the behavior after the OAuth2.0 flow finished.  Meaning, both of the following URLs gave me the same final destination as not having any query params at all:  https://&lt;scratch org random url&gt;.my.salesforce.com/services/auth/oauth/MyCustomAuthProvider?retUrl=lightning%2Fpage%2Fhome   https://&lt;scratch org random url&gt;.my.salesforce.com/services/auth/oauth/MyCustomAuthProvider?startUrl=lightning%2Fpage%2Fhome     Another Update: This WORKED:  https:/&lt;scratch org random url&gt;.my.salesforce.com/services/auth/oauth/MyCustomAuthProvider?startURL=%2Flightning%2Fn%2FCustomPage   Apparently, it was important to add the leading /, (of course, url encoded to be %2F) and %2Flightning%2Fpage%2Fhome gets interpreted as the setup home and sends you there.    (Parallel posted to Salesforce Dev Forum: ) Are both expressions correct? If yes, do they have different meanings? It seems to me that I came across both of them in books, but I'm not sure. How to disable Mac OS X's autocorrect but still show spelling suggestions? I welcome popup spelling suggestions, but I dislike the OS replacing text as I type without any real confirmation from me.   I'm aware both behaviors can be enabled/disabled together as one option in System Prefs &gt; Keyboard &gt; Text, but would anyone know a way to disable the autocorrect while leaving the tooltip-style suggestions intact…perhaps via the Terminal? Thank you.   Mac OS X 9.4 (Mavericks) This might be a stupid question, but I just don't get it. In Hamiltonian mechanics when examining conditions for a $(\boldsymbol{q},\boldsymbol{p})\rightarrow(\boldsymbol{Q},\boldsymbol{P})$ transformation to be canonical one starts with $$ \dot{q}_ip^i-H(\boldsymbol{q},\boldsymbol{p},t)= \dot{Q}_iP^i-\bar{H}(\boldsymbol{Q},\boldsymbol{P},t)+\frac{d}{dt}W(\boldsymbol{q},\boldsymbol{Q},t)$$ where $\bar{H}$ is the transformed Hamiltonian, and $W$ is the generating function (now a function of $\boldsymbol{q}$ and $\boldsymbol{Q}$). This term shouldn't break Hamilton's principle, since $$ \delta\int_{t_1}^{t_2} dt\frac{d}{dt}W(\boldsymbol{q},\boldsymbol{Q},t)=\delta W(\boldsymbol{q},\boldsymbol{Q},t)|_{t_2}-\delta W(\boldsymbol{q},\boldsymbol{Q},t)|_{t_1}=0-0=0 .$$ But I don't see why the variation of $W$ should disappear at the endpoints (say at $t_1$). Expanding leads to: $$ \delta W(\boldsymbol{q},\boldsymbol{Q},t)|_{t_1}=\left(\frac{\partial W}{\partial q_i}\right)_{t_1}\underbrace{\delta q_i(t_1)}_{=0}+ \left(\frac{\partial W}{\partial Q_i}\right)_{t_1}\delta Q_i(t_1)=\left(\frac{\partial W}{\partial Q_i}\right)_{t_1}\delta Q_i(t_1).$$ $\boldsymbol{Q}$ is itself a function of $\boldsymbol{q}$ and $\boldsymbol{p}$, so $$ \delta Q_i(t_1)=\left(\frac{\partial Q_i}{\partial q_k}\right)_{t_1}\underbrace{\delta q_k(t_1)}_{=0}+\left(\frac{\partial Q_i}{\partial p_k}\right)_{t_1}\delta p_k(t_1)=\left(\frac{\partial Q_i}{\partial p_k}\right)_{t_1}\delta p_k(t_1). $$ It seems as if we also needed the variation of $\boldsymbol{p}$ to vanish at the endpoints, and I don't get this because (at least in cartesian coordinates) $\boldsymbol{p}=m\dot{\boldsymbol{q}}$ and the velocity can be different along the original and the varied orbitals even at the endpoints (they can point in totally different directions), so in general $\delta \dot{\boldsymbol{q}}(t_1)\neq 0$. What am I doing wrong? Can someone help me with this, please? How do I reset all progress in the game "just shapes and beats"? The game  has a very unique intro that I would like to show my friend again for the first time. I'm not sure how to reset all my progress on this game to achieve this though. Any thoughts? QM without complex numbers I am trying to understand how complex numbers made their way into QM. Can we have a theory of the same physics without complex numbers? If so, is the theory using complex numbers easier? Is (or will be) there any sort of light linking in Cycles, or a method to get a light to affect only certain objects that doesn't involve compositing two or more different render layers? Sort of what 3Dstudio does with the Include/Exclude methods. Whenever I try to do a fluid simulation, the fluid domain remains visible.  I have tried:ctrl+a-scale, turn on/off visibility for render/viewport  Here's a video demonstrating my problem:   Here's the blend file in case I have messed up some settings:   Thank you for any help! Is static HTML the fastest? Light is clearly affected by gravity, just think about a black hole, but light supposedly has no mass and gravity only affects objects with mass.  On the other hand, if light does have mass then doesn't mass become infinitely larger the closer to the speed of light an object travels. So this would result in light have an infinite mass which is impossible.  Any explanations? How do I unlock all the other ships in the hangar? If $A$ and $B$ are nonempty sets, prove that $A \times B = B \times A$ if and only if $A = B$.   Proving the first direction of this is easy. That is, if $A = B$ then it is obvious that $A^2 = A^2$. I am wondering how to prove the other direction now. Maybe proving it by contradiction will be easier than directly. Proof by induction that $2 + 4 + 6 + \cdots + 2n = n(n+1)$ After upgrading from Ubuntu 13.04 server, the www pages won't display themselves.     Error 403 Forbidden You don't have permission to access / on this server.   I've changed access control saves from apache2.2 to apache2.4, but that didn't work. What else could I do? Adding Grids in Project Manager of QGIS I am using QGIS 3.12. I am new to QGIS after having worked with ArcGIS Desktop for a while. I am having issues with adding a grid to my project. I am using CRS ESPG:3587 WGS 84 / Pseudo-Mercator and noticed that the grid is showing the wrong coordinates and have included the parameters I have set for the grids. How to compute $\lim\limits_{n\rightarrow \infty} \{(2+\sqrt{3})^{n}\}$, where $\{x\}$ is the fractional part of $x$? I've stumbled upon the following problem:  $$\lim_{n\rightarrow \infty} \{(2+\sqrt{3})^{n}\}$$  where "{}" notates the fractional part.  I've never studied this kind of problem, there exists any reference that I could read about this type of problem?