So I recently installed the kde packages, running the command apt install kde-full for installing the kde desktop environment, after test it a while I realize I didn't want it anymore so I remove the packages like this apt remove kde-full, but I notice that some packages and applications remains and weren't completely removed.  I am on Debian 8 distribution. I recently turned to the linux world so any help will be appreciated.  [Edit]  I also tried tasksel --list-task:  u desktop   Debian desktop environment u gnome-desktop GNOME u xfce-desktop  Xfce u kde-desktop   KDE u cinnamon-desktop  Cinnamon u mate-desktop  MATE u lxde-desktop  LXDE u web-server    web server u print-server  print server u ssh-server    SSH server i laptop    laptop   Some packges listing with synaptic-package-manager:    aptitude why kde-base-artwork output:  aptitude why kde-base-artwork i   kdeartwork         Depends kscreensaver (&gt;= 4:4.14.2-1)       i A kscreensaver       Depends kde-workspace-bin                  i A kde-workspace-bin  Depends kde-workspace-data (= 4:4.11.13-2) i A kde-workspace-data Depends kde-base-artwork
I just did my first install of any Linux OS, and I accidentally selected "Desktop GUI" in the install, but I want to build everything myself. Is there any way by which I can remove the GUI environment without re-installing OS?
How to prove that if $a\equiv b \pmod{kn}$ then $a^k\equiv b^k \pmod{k^2n}$ I have a brand new 32GB flash drive that was bought from Hong Kong but manufactured in China.  When I plug it in, it's detected, and when I examine the properties of the drive the size is reported to be 31.2 GB.  Windows forces me to format it but I have not manged to actually do that.  I then I browsed the internet and a forum told me to change the letter to L. After I did that I searched many programs that can help me format it, but when I checked it back, it is 4MB now.  Any idea what's happening with my drive? Why am I seeing two JPG files instead of RAW + JPG with a Canon 1100D? Fast Pixel Search in Java Why is boiling water loud, then quiet? Water in my electric kettle makes the most noise sixty to ninety seconds before the water comes to a full boil. I have been fooled many times by the noisy kettle, only to discover that the water was not yet hot enough for tea. The kettle is only at a full boil after the noise has subsided.    I have noticed the same phenomenon with many other kettles, including conventional kettles on kitchen ranges; it is not a peculiarity of this electric kettle.  Why does the boiling become quieter as the water reaches full boil? A current I flows through a solenoid (with n turns). Self inductance is $L$. If the magnetic flux is $\phi$, I am taught that $-n\phi=LI$  I dont understand the part with $n$, why do we have multiply by $n$? $\phi$ itself represents the whole magnetic flux there, if $\phi$ implied the flux only occurred by one coil, then it would be correct.   Moreover, flux change by a coil ($n$ turns) in $dt$ time is $d\phi$, so the induced electromagnetic force is   $$dE=n \cdot \frac{d\phi}{dt}$$   Why do we multiply by $n$ here? If $\phi$ means the whole flux, then why multiply? I wanted to discuss my intuition of why we formulate the concept of continuity in terms of pre-image of open set is open instead of images for example if we consider $f(x) = c$ where $c$ is some constant, then that should be continuous, but if we formulated continuity in terms of images it won't be continuous. Is the reason we do it that way, because pre-images will always guarantee that function in the domain can only have $1$ value? It seems to me that we could change all the current spin values of particles by multiplying them by two. Then we could describe Bosons as even spin particles and Fermions as odd spin particles. Is there some consequence or reason why we can't simply change 1/2 as the smallest unit of spin into 1?  It just seems prettier this way. In fact, there's almost an interesting relation to even and odd functions in that if you switch any two bosons around the wave function stays the same while if you switch any two fermions around the wave function becomes negative. Find $\,\lim_{x\to 1}\frac{\sqrt[n]{x}-1}{\sqrt[m]{x}-1}$ About fullscreen scrolling webpages There are recently many websites using full screen scrolling pages since Apple launched their own with the iPhone 5C. (website not available anymore, but a reproduction can be found )  Some other examples are:            Is there any study about this practice from the UX point of view? More than about the scroll highjacking, about the use of full screen content?  It seems to me that it's an easy way to present information to the user when used properly and in a simple way, just like a good Power Point presentation. A way to show the user the most important things in a beautiful and smart way.  I see many developers complaining nowadays about this kind of sites, mainly because of the scrolling highjack, but it seems to me users in general, as well as clients, like them.  Any thoughts about this? Launch an app from within another (iPhone) Is it possible to launch any arbitrary iPhone application from within another app?, For example in my application if I want the user to push a button and launch right into the Phone app (close the current app, open the Phone app).  would this be possible? I know this can be done for making phone calls with the tel URL link, but I want to instead just have the Phone app launch without dialing any specific number. Show that the function $g(x) = x^2 \sin(\frac{1}{x}) ,(g(0) = 0)$ is everywhere differentiable and that $g′(0) = 0$ Show that the function $g(x) = x^2 \sin\left(\frac{1}{x}\right) ,(g(0) = 0)$ is everywhere differentiable and that $g′(0) = 0$. I am a computer scientist, and one of my professors today used the symbol $\propto$. I tried to search that using google, but it returns no results, and I do not even know its name.  So, I would like to ask, what does the operator $\propto$ mean? What is its name, and how is it used? How many levels are there for Steam Trading Card badges? With the new Steam Trading Cards, I decided to craft the badge for CS:GO. I got this:    I then noticed that this is only a level 1 badge, and there was a level 2 badge to get. So I crafted it too:    Now it says there's a level 3 badge to get next. How many levels are there in total? Custom DataTable using Vanilla Datables in LWC I'm trying to build a custom datable because I want the functionality to sort, search and paginate and also add action buttons in each row. Initially, my VF page was using  but we have now decided to rebuild that page in LWC.  I found a similar  but it hasn't really worked for me.  I then found  (Javascript) and  (ES2018) I have tried to implement Vanilla Datatables but I keep running into issues such as:      TypeError: Cannot read property 'length' of undefined   The above error is thrown because the library is unable to find the body of the table.   My point is that I feel this library won't work because it's using document, window and so on.   I was wondering if there is a way I could convert this library to something that is more suited to LWC basically have it "export" the modules. Since I'm not a JS expert I'm unable to put the pieces together.   Just for some context, I'll post my code here:  &lt;template&gt;     &lt;table class="sobject-table slds-table slds-table_cell-buffer slds-table_bordered"&gt;         &lt;thead&gt;             &lt;tr class="slds-line-height_reset"&gt;                 &lt;template for:each={fieldSetData} for:item="field"&gt;                     &lt;th key={field.apiName} title={field.fieldLabel} class="" data-scope="col"&gt;                         &lt;div class="slds-truncate" title={field.fieldLabel}&gt;{field.fieldLabel}&lt;/div&gt;                     &lt;/th&gt;                 &lt;/template&gt;             &lt;/tr&gt;         &lt;/thead&gt;         &lt;tbody&gt;             &lt;template for:each={records} for:item="row"&gt;                 &lt;tr key={row} class="slds-hint-parent"&gt;                     &lt;template for:each={row} for:item="data"&gt;                         &lt;td key={data.id} data-label="Name" data-scope="row"&gt;{data.value}&lt;/td&gt;                     &lt;/template&gt;                 &lt;/tr&gt;             &lt;/template&gt;         &lt;/tbody&gt;     &lt;/table&gt; &lt;/template&gt;   import {LightningElement, api, wire} from 'lwc'; import {processRecords} from 'c/recordGenerator'; import getFieldSetData from '@salesforce/apex/FieldSetData.getFieldSetData'; import getSobjectRecords from '@salesforce/apex/DeomoCTRL.getRecords'; import VanillaDatatable from '@salesforce/resourceUrl/VanillaDatatable'; import {loadScript, loadStyle} from 'lightning/platformResourceLoader';  export default class ManageSelectedIndicators extends LightningElement {     @api recordId;     records;     fieldSetData;     @wire(         getFieldSetData,         {objectName: 'SOBJECTName', fieldSet: 'FIELSETName'}     ) wiredFieldSetData({error, data}) {         console.log('wired called in Child')         if (data) {             this.fieldSetData = data;             this.getData();         }     }       constructor() {         super();         console.log('Constructor called in Child');     }      connectedCallback() {         console.log('Connected callback');     }      renderedCallback() {         console.log('Rendered callback');         Promise.all([              loadScript(this, VanillaDatatable + '/VanillaDataTables/src/vanilla-dataTables.js')          ]).then(() =&gt; {              const table = new DataTable(                  document.getElementsByClassName('.sobject-table'),                  //Also tried this.template.querySelector('.sobject-table'),                  {searchable: true, sortable : true}              );          })          .catch(error =&gt; {             console.log(error);          });     }      getData() {         getSobjectRecords ({             sobjectId: this.recordId         })         .then(response =&gt; {             this.records= processRecords(response, this.fieldSetData);         })         .catch((error) =&gt; {             console.log(error);         });     }  }   Edit: I have also tried lwc:dom="manual" that didn't seem to work either.  Is there any other way I could achieve these functionalities? Or do I have to write custom code to achieve this? Does the following series have a closed-form expression:  $$\sum_{k=0}^{\infty} \frac{z^k}{(k!)^2}$$  I know that it must converge because:  $$\sum_{k=0}^{\infty} \frac{z^k}{k!} = e^z$$  and the $(k!)^2$ denominator obviously increases more quickly than the $k!$ denominator.  This problem came up in computing the probability of a draw in a football match with each team's goal scoring modeled as a Poisson process.  Thanks,  John $n^2 + 3n +5$ is not divisible by $121$ Question:  Show that $n^2 + 3n + 5$ is not divisible by $121$, where $n$ is an integer. Ridge & LASSO norms This post follows this one:   Here is my question:  As far as I know, ridge regularization uses a $\ell_2$-norm (euclidean distance). But why do we use the square of this norm ? (a direct application of $\ell_2$ would result with the square root of the sum of beta squared).  As a comparison, we don't do this for the LASSO, which uses a $\ell_1$-norm to regularize. But here it's the "real" $\ell_1$ norm (just sum of the square of the beta absolute values, and not square of this sum).  Can someone help me to clarify? Explaining to an 8-year-old why nothing can travel faster than light I've found some code that could add a modifier but none can set parameters like Octree.