I'm having a very odd problem where the keys F, V and ⌫ (backspace) stop working for no apparent reason!  Then the problem seems to fix itself some time later, to reappear afterwards.  What's causing this and how to avoid it? It's getting really annoying. And I don't understand why only those 3 keys fail to work, the rest of the keyboard works just fine.  I don't think it's really a hardware issue. I'm on High Sierra 10.13.2. I use Karabiner-Elements to program some keys and at first I thought it could be the culprit (even though I have used it for a long time with no issues), but the problem persists even after quitting that app.

This is an attempt to write a canonical QA for this issue, as per the Meta post:   I expect it to be periodically edited with the goal of becoming a comprehensive information resource.  I have a MacBook Pro that has a key(Shift, Return,   Command, P, etc.) that doesn’t respond when pressed or is stuck in the down position.    It's possible that my favorite beverage was spilled (or some other liquid damage).  It's also possible that I have no idea what happened.  It was working yesterday and suddenly today it's no longer working.  Is there any way to bypass or remap the key?  Can I  have the system ignore it completely?  (This question can also apply to external USB keyboards or the Bluetooth keyboards)


I have an issue with solutions I've encountered to showing that sequence $\{s_n\}$ converges where $s_{n+1} = \sqrt{2 + \sqrt{s_n}}$  The question states: If $s_1 = \sqrt{2}$ and $s_{n+1} = \sqrt{2 + \sqrt{s_n}}$ for $n \in \mathbb{N}$ prove that $\{s_n\}$ converges and that $s_n < 2$ for $n \in \mathbb{N}$  In particular I have issue with the way this and another solution I saw went about getting the answer. The start of the solution is as follows:    If it specifically says I have to show $s_n < 2$ how are they allowed to all of a sudden use this "unknown fact" in establishing that the sequence is bounded? I get that it is a good way to then be able to apply the monotone convergence theorem, but it explicitly says to show this. I don't see how this constitutes making the proof sound.

Let $a_n$ be the sequence in $\mathbb{R}$ given by:  $$ a_1 = \sqrt{2}, \; \; a_{n+1} =\sqrt{2+ \sqrt{a_n} }. $$  Show that this sequence converges and find the limit.  I have already proven that this sequence is increasing and bounded by $2$, so the limit exists. Now, when I'm trying to find the limit, say  $L$, I get that $L$ satisfies the equation: $$L^2 -2 - \sqrt{L}=0, $$ but I don't actually know how to solve this equation, so I would like to know if there is an  easier way to find the limit, and in case I must solve the last equation, how can I solve it?  Thanks in advance!


need to find timezone from time zone Offset. example: localTimestamp":"2019-08-26T16:09:45.5003126+05:30.Need to find the time zone like "timezone": "America/Los_Angeles", Any Api i can use?

Does the .Net DateTime contain information about time zone where it was created?   I have a library parsing DateTime from a format that has "+zz" at the end, and while it parses correctly and adjusts a local time, I need to get what the specific time zone was from the DateTime object.   Is this possible at all? All I can see is DateTime.Kind, which specifies if time is local or UTC.


I need a backup software for Ubuntu 14.04 that has a GUI that can backup my entire system to an external hard drive or network drive. Any recommendations?

This question exists because it has historical significance, but it is not considered a good, on-topic question for this site, so please do not use it as evidence that you can ask similar questions here.  While you are encouraged to help maintain its answers, please understand that "big list" questions are not generally allowed on Ask Ubuntu and will be closed per the .   Backup is incredibly important. Obviously there's no best backup tool, but a comparison of the options would be very interesting.   Graphical Interface? Command line? Incremental backups? Automatic backups? Install method: In standard repositories? PPA?


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

How do you write (and run) a correct micro-benchmark in Java?  I'm looking for some code samples and comments illustrating various things to think about.  Example: Should the benchmark measure time/iteration or iterations/time, and why?  Related:


What's the easiest way to install a list of packages with latest version?  Using apt-cache policy or Ubuntu software center, package xxxx only has version 1.1 In Pypi (), the latest version is 1.5. I do not fancy installing from the download file (.tar.gz). Why isn't the latest version reflected in the Ubuntu software center?

Why are packages in the official Ubuntu repositories older than the latest (upstream) versions from Debian Sid, PPAs, the authors, etc.?


Is the set $I \times I \subset \mathbb{R}^2$, where $I = \mathbb{R}\setminus \mathbb{Q}$ path connected? It seems like it could be. Consider the path $\gamma : (0,1) \to \mathbb{R} \times \mathbb{R} $ given by $\gamma(t) = \left(t, (1 - t^3)^{\frac{1}{3}}\right)$. Fermat's last theorem guarantees $\gamma((0,1)) \subset I \times I$. Thus, $\gamma$ is a path of non-zero length contained in $I \times I$. Perhaps paths like $\gamma$ could be glued together to connect any two points of $I \times I$? Edit As has been pointed out below, it is not the case that $\gamma((0,1)) \subset I \times I$. Clearly $\gamma(q) \in \mathbb{Q} \times \mathbb{R}$ when $q \in \mathbb{Q}$. Fermat's theorem only guarantees that $\gamma((0,1)) \subset \mathbb{R} \times I$. I had in mind the arc given implicitly by the equation $x^3 + y^3 = 1$ for $x,y \in (0,1)$. While this arc will be a subset of $I \times I$, it is in fact totally disconnected.

Let $A$ be a countable subset of $\mathbb{R}^2$. Show that $\mathbb{R}^2-A$ is path connected.  These are my steps:   Let $x$ and $y$ be arbitrary points of $R^2$ Let $f^r:[0,1] \to \mathbb{R}^2$ be given by $f^r(t)=(1-t^r)x+t^ry$ for $r \in\mathbb{R}$.  Show that $f^r$ is a continuous path between $x$ and $y$ and that non of them intersect. Show that $f^r$ is bijective with $\mathbb{R}$ through $F(f^r)=r$ and conclude that there are uncountable non intersecting paths. Assume for the sake of contradiction that $A$ intersects all of the paths $f^r$ and deduce that $A$ must be uncountable (since it must intersect every $f^r$ at a different point).  Contradiction! ($A$ is countable) Hence there exist a paths $f^r$ for some $r \in\mathbb{R}$ which doesn't intersect $A$. $\mathbb{R}^2-A$ is path-connected.     Is this proof sound?


I reread Tim Gowers protest against Elsevier as well as other writings from well-known professors that indicate they still protest.    I'm also aware of the boycott.  Has this protest actually changed Elsevier's business practices?

Starting around 2012, Timothy Gowers had  about the practices of Elsevier. Very roughly speaking, he argued that Elsevier made research articles expensive to access and profited heavily from the volunteer work of peer reviewers. Sympathetic individuals established a website called "", which hosts the electronic signatures of over 15,000 academics who have agreed to boycott Elsevier to some degree.  Things are relatively quiet now compared to the flurry of activity that followed Gowers' series of posts. The most recent information I can find is  from the editorial board of Elsevier's "Journal of Number Theory", which was posted to Gowers' blog in May of 2013. In it, Martin writes (emphasis mine):     As far as I can tell, Elsevier’s responses to our concerns ended up being limited to a slight easing off of support for legislation limiting access to our research, together with a nominal reduction in individual journal prices. Regarding the latter, however, Elsevier’s “bundling” practice remains in place, making individual journals’ prices essentially irrelevant. Their (aggressively defended) lack of pricing transparency from one institution to another also speaks volumes, in my mind, to the limits of their desire to seriously address our pricing concerns.   My feeling is that not much has changed in the past two years, particularly since I would expect to hear an update from Gowers if any major victories had been won.   Can anyone provide more up-to-date information about Elsevier's pricing, bundling, and access practices?


How to place parallel text on two pages? Lorem ipsum... and Sed saqittis... are original texts (paragraphs). Maecenas... and Aliquam... are translated texts (paragraphs). I read about reledmac and reledpar, but I can't put the title (\huge{\textbf{Title}} works, but there's not a section anyway) and also there's no way to leave blank line between paragraphs. (\pstart[\vline] doesn't work). Is there some way to create kind of this document?

I want to typeset a bilingual text in parallel on facing pages using LuaLaTeX. The existing solutions to automate this task have proven unsatisfactory as they don't allow for footnotes (parallel), don't allow for different font sizes of the two parallel texts (), or generally provide a poor result of aligned text chunks (eledpar).  As the text is not too long, I really came to consider breaking the pages myself. For this to do, I have to solve the following problem(s):  Consider two facing pages with ending paragraphs of different length. The following paragraphs should then begin at the same vertical position such that the beginnings of these following paragraphs face each other. For this to accomplish on has   to determine the position of the end of the longer paragraph on its page to have the means to let the next parallel paragraphs both begin at the identified position.   Is this something which is doable? Are there mechanisms provided by (Lua)LaTeX to determine positions on a page and to begin typesetting at a specific position on a page?  EDIT: The following example illustrates the task. Here the latin paragraph starting with "O tempora, o mores" (third chunk of text in the code) should begin at the facing position of the beginning of the paragraph "Shame on the age..." (fifth chunk).  \documentclass[a6paper]{scrbook} \usepackage{fontspec} \usepackage[latin,english]{babel} \begin{document} \mbox{}\pagebreak  \noindent\selectlanguage{latin}{\large quo usque tandem abutere, Catilina, patientia nostra? quam diu etiam furor iste tuus nos eludet? quem ad finem sese effrenata iactabit audacia? nihilne te nocturnum praesidium Palati, nihil urbis vigiliae, nihil timor populi, nihil concursus bonorum omnium, nihil hic munitissimus habendi senatus locus, nihil horum ora voltusque moverunt? patere tua consilia non sentis, constrictam iam horum omnium scientia teneri coniurationem tuam non vides? quid proxima, quid superiore nocte egeris, ubi fueris, quos convocaveris, quid consili ceperis quem nostrum ignorare arbitraris?\par\newpage}  \noindent\selectlanguage{english}When, O Catiline, do you mean to cease abusing our patience? How long is that madness of yours still to mock us? When is there to be an end of that unbridled audacity of yours, swaggering about as it does now?  Do not the nightly guards placed on the Palatine Hill — do not the watches posted throughout the city — does not the alarm of the people, and the union of all good men — does not the precaution taken of assembling the senate in this most defensible place — do not the looks and countenances of this venerable body here present, have any effect upon you? Do you not feel that your plans are detected? Do you not see that your conspiracy is already arrested and rendered powerless by the knowledge which every one here possesses of it? What is there that you did last night, what the night before — where is it that you were — who was there that you summoned to meet you — what design was there which was adopted by you, with{\parfillskip0pt\relax\par}  \noindent\selectlanguage{latin}{\large O tempora, o mores!\par\newpage}  \noindent\selectlanguage{english}which you think that any one of us is unacquainted?  Shame on the age and on its principles! \end{document}


I am new to subject static electricity and I really got confused by some questions?   if the electrons in insulators are tightly bound to the nucleus why when rubbing two insulators electron jump from one to another?  in conducting wires when an electron jump from one atom to another they repel each other and form an electrical current but why when electron transfer from one insulator to another the the electrons from the second insulator doesn't repel the electron transferred from first insulator?

It is always told as a fact without explaining the reason. Why do two objects get charged by rubbing? Why one object get negative charge and other get positive ?


Trying to identify a short story. I recall it was quite short, shorter than a novella. I read it within the last few years, but my impression is that it's from the second half of the twentieth century, maybe the sixties. I can't recall if I read it online, in an anthology, or collection. Set in America, a middle-aged man stumbles on a team (maybe like dwarves or gnomes) whose job it is to set up the world for the next day by removing all the previous day's "stuff", like street furniture? (I know that makes no sense). He disrupts this process and somehow prevents progressing to the next day. I also remember the story was quite lighthearted with the team behaving in a very grumpy way like interrupted workmen. I thought the title was something like "What happened to Tuesday" or similar. For some reason, I thought it was by Keith Laumer, but a search doesn't reveal anything. The trope was similar to "The Tunnel Under the World" by Pohl, and "The Adjustment Team" by Dick, in that reality was constantly changed and controlled by an organisation of some kind.

Does anyone know a SF TV short story in which there were blue men who helped "stage" our world- at least the parts we saw, on a minute by minute basis.  So, at each minute, everyone would be in the "world" that was built for that minute, then they would go on to the next "minute world".  The blue men were in the future minutes building most of reality, but only the parts that would be looked at at that minute (to save work, I think - why build something that will not every be "used")  And they were in the past tearing down all the previously lived minutes.  It was kind of a behind the scenes look at why when you set your keys down and come back to them, they aren't there. Then you look again a few minutes later and they are there. The reason in the show was that the blue men building that minute forgot to include your keys, but the next group got it right.  Years later, my wife and I still refer back to that show, so I would like to find out what it was and see if I can find a copy somewhere.  .


I am working on a ML problem to predict house prices and Zip Code is one feature which will be useful. I am also trying to use Random Forest Regressor to predict the log of the price.  However, should I use One Hot Encoding or Label Encoder for Zip Code? Because I have about 2000 Zip Codes in my dataset and performing One Hot Encoding will expand the columns significantly.

I have been building models with categorical data for a while now and when in this situation I basically default to using scikit-learn's LabelEncoder function to transform this data prior to building a model.  I understand the difference between OHE, LabelEncoder and DictVectorizor in terms of what they are doing to the data, but what is not clear to me is when you might choose to employ one technique over another.    Are there certain algorithms or situations in which one has advantages/disadvantages with respect to the others?


Very much related:   An answer on the linked post leads to suggest that Alchemist's Fire burns as long as it is not actively extinguished by somebody.  However, a comment on the same answer indicated that Alchemist's Fire doesn't release light, because light isn't mentioned with the description of the item.  I'm looking for any RAW material that indicates whether or not Alchemist's Fire produces light, and how long it can burn for on an inflammable object.    If there is no such material, then I am even willing to accept information from prior versions that cover this same information.  If there is no information on Alchemist's Fire itself, then a RAI answer can be acceptable if it includes the process with how Alchemist's Fire is made (to draw a conclusion about what kind of light/duration could be expected).  Alchemist's Fire in 5e, per :     This sticky, adhesive fluid ignites when exposed to air. As an action, you can throw this flask up to 20 feet, shattering it on impact. [...] The target takes 1d4 fire damage at the start of each of its turns. A creature can end this damage by using its action to make a DC 10 Dexterity check to extinguish the flames.

Looked and looked, can't find the answer anywhere (maybe I'm blind):  How long does Alchemist's Fire burn for?  In the item description within , it says:     On a hit, the target takes 1d4 fire damage at the start of each of its turns. A creature can end this damage by using its action to make a DC 10 Dexterity check to extinguish the flames.   Yet no mention of the burn rate.  One round after a hit?  2?  A minute?  Continuous until extinguished?


As I am browsing the resources online, I encounter as least three ways to detect overdispersion after fitting a Poisson regression model.  1) A regression approach proposed by Cameron and Trivedi, 1990  2) The Lagrange Multiplier test  3) A third test proposed by Greene found below     I found literature references to 1) and 2), but am having a hard time finding anything related to 3). Since every test has it own assumptions and limitations, would anyone shine some light on what passing/failing each test entails?

I have count data (demand/offer analysis with counting number of customers, depending on - possibly - many factors). I tried a linear regression with normal errors, but my QQ-plot is not really good. I tried a log transformation of the answer: once again, bad QQ-plot.  So now, I'm trying a regression with Poisson Errors. With a model with all significant variables, I get:  Null deviance: 12593.2  on 53  degrees of freedom Residual deviance:  1161.3  on 37  degrees of freedom AIC: 1573.7  Number of Fisher Scoring iterations: 5   Residual deviance is larger than residual degrees of freedom: I have overdispersion.  How can I know if I need to use quasipoisson? What's the goal of quasipoisson in this case? I read this advise in "The R Book" by Crawley, but I don't see the point nor a large improvement in my case.


Let $G$ be a finite group. If, for each positive integer $m$, the number of solutions of the equation $x^m = e$ in $G$, where $e$ is the identity element, is at most $m$, then can we conclude that $G$ is cyclic?

Let $G$ be a finite group. For each positive integer $m$, if $x^{m}=e$ has at most $m$ solutions in $G$, $G$ is cyclic.   What I have thought is that $n=\sum_{d\mid n}\phi(d)$ can be used to solve this and showing that $|G|$ order element in $G$ exists is enough.


about a year ago, I removed a little too many apps from my Computer with Remove-AppxPackage. Since then my Windows Store is missing.  I know I could reinstall the Windows Store by using this command:  Get-AppXPackage *WindowsStore* -AllUsers | Foreach {    Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml" }   The thing is, It doesn't even find the package at all, so Get-AppxPackage *Store* -AllUsers returns nothing at all.  How can I get my Windows Store back, without reinstalling / updating my OS? (by reinstall I mean a completely new blank installation, by updating an update to a newer version like 1809)  My OS is Windows 10 Version 10.0.14393.0  Note: I also tried the usual stuff like:   sfc /scannow dism /online /cleanup-image /RestoreHealth   but that also did not work. Any help is appreciated!

I had remove the Microsoft Store application. Yes, totally remove the app. Do not ask how and what for. :)  Is there a convenient way to set it up again or restore it? Anything except "system restore"...  Upd. I used  to remove everything. And it works so good that nothing can be found again. :) or :(.  [Get-AppxPackage Microsoft.WindowsStore] returns nothing.  Search for [Microsoft.WindowsStore] returns only:   C:\Documents and Settings\All Users\Microsoft\Windows\AppRepository\Packages\Microsoft.WindowsStore_2015.7.1.0_neutral_split.scale-200_8wekyb3d8bbwe [Folder is empty] C:\Documents and Settings\All Users\Microsoft\Windows\RetailDemo\OfflineContent\Microsoft\Content\en-gb\AppData\Microsoft.WindowsStore_8wekyb3d8bbwe [Folder contains only 3 jpg] C:\Documents and Settings\All Users\Microsoft\Windows\RetailDemo\OfflineContent\Microsoft\Content\Neutral\AppData\Microsoft.WindowsStore_8wekyb3d8bbwe [Folder contains only 3 jpg] C:\Documents and Settings\All Users\Microsoft\Windows\AppRepository\Microsoft.WindowsStore_2015.7.1.0_neutral_split.scale-200_8wekyb3d8bbwe.xml C:\Documents and Settings\All Users\Microsoft\Windows\AppRepository\Microsoft.WindowsStore_2015.701.14.0_neutral_~_8wekyb3d8bbwe.xml


According to , it is possible to add "destinations" to a PDF file that can be used to navigate directly to certain places in the document when opening it:     Open a PDF file to a set destination      A destination is the end point of a link represented by text in the   Destinations tab. Destinations enable you to set navigation paths   across a collection of Adobe PDF documents. Linking to a destination   is recommended when linking across documents because, unlike a link to   a page, a link to a destination is not affected by the addition or   deletion of pages within the target document.      To set a Destination in Acrobat 7.0 (Professional or Standard):         Set the Zoom and page location to the way you want it on the screen.   Select View > Navigation Tabs > Destinations to open the Destinations tab.   Select Options > New Destination from the Destinations tab.   Give the Destination a name.   Create an HTML link that points to this destination by adding #[destination name] to the end of the links URL.         For example, this HTML tag opens a destination named "glossary" in a   PDF file named myfile.pdf:      <A HREF="http://www.example.com/myfile.pdf#glossary">   Using pdflatex and hyperref, is there a way to place these "destinations" in the PDF output file? Is it possible to automatically add \labels as destinations?

According to the Evince help, one can open a PDF at the location of a "named destination":  SYNTAX        evince [--help]  [--page-label=PAGE |  --page-index=NUM‐        BER | --named-dest=DEST] [--fullscreen] [--presentation]        [--preview] [--find=STRING] [filename(s)...] ...        -n, --named-dest=DEST               Open the document on the specified named destina‐               tion.   In Acrobat (acroread) the corresponding command is ()  acroread /a "nameddest=pos2" hyperref.pdf   How can I generate such named destinations in a PDF from LaTeX?  In the past, (mainly for Acrobat) I used the zref-savepos package to open the document at a desired location (set at compilation). This doesn't seem to work well with Evince.  The question is not so much about Evince but what is that Evince calls "named destination" and how to produce them.  Below it is a series of attempts I made. When running Evince I get the following messages:  $ evince hyperref.pdf -n pos3 #or pos2 failed to look up pos3 failed to look up pos3   MWE  \documentclass[]{article} \usepackage{hyperref} \hypersetup{pdfstartview=FitBH \hypercalcbp{\zposy{pos2}sp}} %open at pos2 (works only in Acrobat) \usepackage{bookmark} \usepackage{zref-savepos} \begin{document}  \zsavepos{pos1}  Bla  \zsavepos{pos2}  Ble  \belowpdfbookmark{Pos3}{pos3}  Bli  \end{document}


Assuming either $|z|=1$ or $|w|=1$ , prove that  |$\frac{z-w}{1-\bar zw}$| $=1$  When assuming that only $|z|=1$, we can easily deduce that $|{z-w}|=|{1-\bar zw}|$  But it's more complicated when we take the case where only $|w|=1$   Any hints please ?

Let's suppose that $|z|<1$ and $|w|=1$. Show that the modulus of $\displaystyle \frac{z-w}{1-\bar{z}w}$ is always $1$. Some hint.


How are folks finding players these days? I'm looking for Warhammer Fantasy Roleplay 4th edition enthusiasts. (It was very recently released.) I'm also finding that remote play is more realistic than being able to sit down at a table with others.

I'd really like to learn how to play pen-and-paper RPGs.  I know that it takes a few players to actually sit down and play, but I'm not at all sure where to find more gamers.  How do I find existing groups to join? Or, are there any resources online that may help me find existing RPG groups or players?


When writing a letter, or other form of written work, what is the appropriate way to put emphasis on a word or phrase?  When would one use bold?  When would one use italics?  When would one use an underline?  Do they all mean the same, and their usage is simply a matter of preference?  Edit  I would like to know the definition for each of the above, and why you would use one over the other, specifically in writing a letter or other such document.  For example:  This question is not a duplicate.  This question is not a duplicate.  This question is not a duplicate. (I can't use the HTML tag for underline in HTML 5...)

Let’s say I have many lists of this kind on a page:   Click on the Foo button. Tick the Bar box. Click on the Save button.   How should I emphasize Foo, Bar, and Save?   Bold?   Click on the Foo button. Tick the Bar box. Click on the Save button.  Italic?   Click on the Foo button. Tick the Bar box. Click on the Save button.  Quotes?   Click on the “Foo” button. Tick the “Bar” box. Click on the “Save” button.    NOTE: I want the lists to be read as easy as possible.


I have a document, one in particular, that tends to be edited by a lot of contributors with varying versions of Office. This document when opened in Excel 2007 does not open into an MDI window with the full set of controls, but is instead in a fixed size window. How can this be resolved?  See screenshot, ignore the blacked out content:

I have a lot of Excel sheets for all sorts of things - but none has ever acted up like this one here:    This used to be a totally normal Excel 2007 sheet which I was able to resize, maximize etc. - but not anymore. The MDI child window is fixed, both in position and size. I cannot move it around, more can I maximize it to use the full size of the screen anymore. I cannot double-click on it's title bar to maximize it either :-(  What happened? What can I do to "undo" whatever I did to it.  Any ideas? I tried to share / undo sharing, I tried to protect / unprotect the sheet - nothing seems to work...


I have a Mac Server 3.1.2, w/ system 10.9.4 that is not being used as DNS Server. Windows Server 2012 is DNS & DHCP server. On the Mac, Terminal cannot ping hostname of mac, however, it does identify itself with it's hostname so I'm concluding this mismatch is the cause of my issues.  Anyone have a suggestion?

I've got a handleful of macs (all with unique names) and on occasion it prompt a notice about saying another computer on the network as this name and adds a (2) or (3) to my mac.    How can I set the host name from the command line?


In general density is mass/volume. Also it's used for something like population density, which is population/unit area. What is significance of word density in PDF?

On the , there is this line:      $p(\mathrm{height}|\mathrm{male}) = 1.5789$ (A probability distribution over 1 is OK. It is the area under the bell curve that is equal to 1.)    How can a value $>1$ be OK? I thought all probability values were expressed in the range $0 \leq p \leq 1$. Furthermore, given that it is possible to have such a value, how is that value obtained in the example shown on the page?


Prove: $\sqrt{2}+\sqrt[3]{5}$ is irrational    I have tried to look at $1+\sqrt{2}+\sqrt[3]{5}$ but I can see how to continue

How can I prove that the sum  $\sqrt 2+\sqrt[3] 3$  is an irrational number ??


How to compute integral $\int_{-\infty}^\infty e^{-\frac{1}{2}x^2}dx$? I try to change it to polar coordinates but I have only one variable.   Thanks in advance!

Consider the following Gaussian Integral $$I = \int_{-\infty}^{\infty} e^{-x^2} \ dx$$  The usual trick to calculate this is to consider $$I^2 = \left(\int_{-\infty}^{\infty} e^{-x^2} \ dx \right) \left(\int_{-\infty}^{\infty} e^{-y^{2}} \ dy \right)$$  and convert to polar coordinates. We get $\sqrt{\pi}$ as the answer.   Is it possible to get the same answer by considering $I^{3}, I^{4}, \dots, I^{n}$?


Receiving e-mails, I end up with "complete from strings" such as this one:  $test = '=?UTF-8?Q?Test=C3=B6p?= <no-reply@Testöp.tld>';   How do I get rid of the "=?UTF-8?" nonsense? Obviously I don't mean to just string-replace it, but to convert it properly to an actual UTF-8 string. It's supposed to be something like:  $test = 'Testöp <no-reply@Testöp.tld>';   I don't know why I get this in the first place, but I bet there is a simple function to do it somewhere in PHP.  Note: It's not utf8_decode()! That one does nothing to that string!

I have the string which that encoded in .  How do I decode this in php?  Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Vestibulum felis = pede, vestibulum et, ullamcorper in, ultrices eget, metus. Suspendisse in n= ulla. Sed justo. Donec dapibus auctor neque. Pellentesque faucibus ante nec=  metus. Vivamus feugiat, velit rhoncus semper suscipit, libero augue venena= tis leo, nec ornare nulla elit eget diam. Nullam sollicitudin.


How can I use command line tools like ls, grep from python.

How do you call an external command (as if I'd typed it at the Unix shell or Windows command prompt) from within a Python script?


The tutorial says the intersection point for L1 and L2 regularization gives the minimum loss - But why the intersection gives the minimum loss? I cannot interpret the graph clearly.

I have been reading many articles on LASSO regression, and everyone claims that LASSO address multicollinearity showing contour plots of cost function touching the corner of the diamond(x1+x2). In the first place, I didn't understand how does this phenomenon translate to addressing multicollinearity when there are many groups of correlated variables in the data.  Verbatim from one of the research paper: "• If there are grouped variables (highly correlated between each other) LASSO tends to select one variable from each group ignoring the others".


How can I show the existence of a injection $\phi:\{x|x \subset \omega \} \rightarrow \{f|f:\omega \rightarrow \omega$ is bijective$\} $?

I guess it is too difficult a question to ask about the cardinality of $S_{\mathbb{N}}$ so I would like to ask whether it is countable or not.  I tried to prove it is uncountable somewhat mimicking the Cantor's diagonal argument but failed.


Amateur photographer looking to get serious.  Own a Canon T2i at the moment with two kit lenses, 50mm f/1.8 and just bought a Tamron AF 18-270mm f/3.5-6.3 Di II VC LD Aspherical IF Macro Zoom Lens.    My question is:  Should I be more concerned with purchasing lenses or upgrading the camera to a 60D/70D?

I read somewhere on this site itself that you should spend more on your lenses and less on your camera bodies.  Is it a myth or a fact that mostly it is the lenses which make your photographs not the camera bodies? If it is true, then on what basis?


Why a bigger drop of water splits into many tiny droplets while falling from a height?    $$OR$$      Why the cohesive force becomes weak when water is allowed to fall freely?

Why is it that raindrops don't collide and 'stick together' on their descent to Earth, arriving in streams rather than separate drops?


I'm doing this with VMs. I'm using virtualbox and I made the mistake of creating a server with a dynamic disk. I then proceeded to create another virtual disk, a fixed one, into which I cloned the server OS. This because sda1 would not grow in size as it's supposed to in a dynamic disk, instead creating an extended partition and some other.  Having the server on a fixed disk did not help as sda1 remained the same size, only the extended partition got bigger.  So, I added that disk to a desktop version VM I had so I could comfortably use gparted and make the partition bigger manually.  Now, the extended partition and the other one (sda5) I don't remember the filesystem of, had these key symbols, and even running gparted with root privileges wouldn't let me delete or change those in any way.  So I turned to fdisk. I was able to easily delete sda2 and sda5, and then use gparted to make sda1 bigger. I left 1Mb at the end.  The problem I'm having now comes in here. The server will still say it doesn't have enough space to do this or that, even though it does.  server@ubuntu:~$ df -h Filesystem      Size  Used Avail Use% Mounted on udev            2.5G     0  2.5G   0% /dev tmpfs           508M  7.3M  501M   2% /run /dev/sda1       2.8G  2.7G     0 100% / tmpfs           2.5G     0  2.5G   0% /dev/shm tmpfs           5.0M     0  5.0M   0% /run/lock tmpfs           2.5G     0  2.5G   0% /sys/fs/cgroup /dev/sdb1        15G   47M   14G   1% /home/server/sxtngig tmpfs           508M     0  508M   0% /run/user/1000 server@ubuntu:~$ lsblk NAME   MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT sda      8:0    0    8G  0 disk └─sda1   8:1    0    8G  0 part / sdb      8:16   0   15G  0 disk └─sdb1   8:17   0   15G  0 part /home/server/sxtngig sr0     11:0    1 1024M  0 rom   As you can see, it has 8Gb but df can't see it. Is there a way I can make the server refresh the disk space? Maybe something in a file I need to change?

I rent a VPS that uses a SSD of 10GB (Debian 7) and I upgraded yesterday to their "second tier" plan that uses a 20GB disk. However, the "one-click-upgrade" process didn't work as I expected and what they did was to move my data to a bigger drive without actually extending the partitions. So now I have 10GB of unallocated space.  I do run around 5 websites on this VPS with mail accounts and all that jazz and I'm very scared to mess up anything so I called their support and they offered to do the job for me for 80 EUR that I find unacceptable since I thought it was included when doing the upgrade. Their older offers from last year used to be just a one click job but the excuse is that "SSD's are different, so it's up to the user".  Anyway, how can I actually do that without screwing things up and is it possible to do that on a "live" system?  I know a couple of commands so here it goes what I could find:  root@vpsxxxxxx:~# df -h Filesystem      Size  Used Avail Use% Mounted on rootfs          9.9G  7.6G  1.8G  81% / udev             10M     0   10M   0% /dev tmpfs           388M  200K  388M   1% /run /dev/vda1       9.9G  7.6G  1.8G  81% / tmpfs           5.0M     0  5.0M   0% /run/lock tmpfs           775M     0  775M   0% /run/shm /dev/vda1       9.9G  7.6G  1.8G  81% /var/www/clients/client2/web2/log /dev/vda1       9.9G  7.6G  1.8G  81% /var/www/clients/client1/web3/log /dev/vda1       9.9G  7.6G  1.8G  81% /var/www/clients/client3/web5/log /dev/vda1       9.9G  7.6G  1.8G  81% /var/www/clients/client5/web7/log /dev/vda1       9.9G  7.6G  1.8G  81% /var/www/clients/client4/web6/log  root@vpsxxxxxx:~# fdisk -l  Disk /dev/vda: 21.5 GB, 21474836480 bytes 4 heads, 32 sectors/track, 327680 cylinders, total 41943040 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000     Device Boot      Start         End      Blocks   Id  System /dev/vda1   *        2048    41943039    20970496   83  Linux  root@vpsxxxxxx:~# sfdisk -l  Disk /dev/vda: 41610 cylinders, 16 heads, 63 sectors/track Warning: The partition table looks like it was made   for C/H/S=*/4/32 (instead of 41610/16/63). For this listing I'll assume that geometry. Units = cylinders of 65536 bytes, blocks of 1024 bytes, counting from 0     Device Boot Start     End   #cyls    #blocks   Id  System /dev/vda1   *     16  327679  327664   20970496   83  Linux /dev/vda2          0       -       0          0    0  Empty /dev/vda3          0       -       0          0    0  Empty /dev/vda4          0       -       0          0    0  Empty


I am Filipina and I'm in Switzerland right now together with my sponsored, and my 30 days Schengen visa for housemaid will going to expire on Aug 25 '2014, Can I extend my visa till 31 of Aug 2014 from Switzerland? Where I can go to process my visa?

I am currently working in Switzerland on work permit and my parents obtained a Schengen Visa for travel which has a validity of 90 days. In the visa, the duration of stay is mentioned to be 55 days  - this is same as the original itinerary of the travel.    Now that they are in Switzerland for last 40 days - I wish to extend their stay for couple of more weeks which would result in their duration of day as 75 days (which is more than 55 days but well within 90 days of validity).  Could anyone please suggest if I would need a formal approval process from local canton or national immigration office?


I want to write to first line of an existing text file which has plenty of lines in it. I just wanted to add one line at the starting of the file.

What is the easiest way to add a text to the beginning of another text file in Command Line (Windows)?


I read this at least twenty years ago, but have no idea how old the book/story was.  Set in some indeterminate point in the future, typical have & have nots style.  The youth battle each other using various weapons but guns are banned for not being 'sporting' (not sure if all projectile weapons treated the same).  The protagonist uses nunchucks and is a loner.  Somehow he gets involved with some science group who are investigating weird growths somewhere.  He gets injured during this but has something in his pores that 'crawl' out and heals wounds but somebody doesn't understand them and keeps picking them off.  The only thing I recall is that he actually has a shotgun shell embedded in one end of the nunchucks so this could be used as gun if necessary.

Not everyone was a citizen though, there was a significant underclass who had no shares.  One character was a celebrity in some sort of combat game who was followed by camera drones & used drugs to suppress puberty so he waa an eternal 'child', I have the impression that medical science allowed virtual immortality short of accidents.  One character (may have been the same one) had had a 'previous life' & had committed personality suicide by some form of mind wipe bequeathing his worldly possessions to the new personality that would eventually develop in his old body.  I think the motive for this 'suicide' was essentially boredom, he'd lived a long time.  The mind wipe in question was pretty extensive & all encompassing, he had to be cared for & educated from scratch as if a newborn baby in an adult body, nappies & all (but I'm pretty sure this was purely backstory in the book I read).  He also had miniature nano organisms (or bots?) like miniature worms or millipedes that complimented his immune system & aided healing, they were self replicating, pretty sure they were some sort of bioengineered organism tailored to his DNA rather than bots  but not 100% on that.  There was an organism spanning a large area on the planet that absorbed (or consumed) anything that wandered into it but saved the DNA of anything it had previously absorbed & might randomly reproduce any animal plant or individual it had previously absorbed fully formed.  One of the characters fell into this but got pulled out before the full effects took hold, as a result he grew leaves from his head & his immune system was then constantly battling with the 'infection'.  When did I read this? probably some time in the 80's in the UK.  When was it written? I haven't a clue, sorry.  It was a paperback, probably something I had out of a library, because I never get rid of anything I've bought myself so I'd still have it & be able to dig it out if it wasn't a library loan.  I have lots of fragments of world background & 'colour' that seem to have stuck in my mind there, but a complete lack of any story arc to go with them.


Chaos is not a random process, although it may look like one. If I am given a set of observations, is it possible to determine if the observations are generated by a random process or if they are generated by a chaotic process? What properties or characteristics of the observations can be used to make that determination if it is possible?

Are there any simple experimental or statistical tests to check whether a dynamical system is deterministic?


First of all please forgive my lack of experience in illustrator, I've just started out and am therefore a complete novice in design.  I've just created my logo, saved and exported it as an SVG. It appears how I want it in Illustrator with just colour fills and no strokes, but in the browser a light stroke colour is being applied to each path. I used the live paint bucket tool to fill in the different shapes with different shades. Anyone know what I've done wrong here?

I converted a raster image to vector in Illustrator CS6 using Image Trace then the Expand option, though when I save as an svg the image looks embossed. I suspect it's due to the layer background being white and the paths not lining up, but I'm unsure how to fix it or prove that theory without manually having to adjust every path.   This is how it looks in Illustrator before I export it:    The image looks like this when saved/exported with art optimized option:


I can't find the rendered image result. The render work perfectly but when I reopen the file there is only a blank grey screen. This has not happended before.Please help.

Is it possible to render an image and have blender remember it, so that next time I open the file the render result will not be blank?  I am not talking about saving to an external file.  Specifically I would like to render an image, close blender, and come back later and be able to do some compositing on the render without having to waste a half an hour rendering it again (my GPU drivers are messed up so I have to use the CPU).  Currently the render result is blank when ever I open a file.


Say an electron begin moving with velocity V back and forth very quick or at the speed of light, could it interact with its own previous pre existing electromagnetic field?

I read this in my textbook: A charged particle or object is not affected by its own electric field.  Since I find this completely unintuitive and my mind is yelling "wrong! wrong! how could a particle even distinguish between its own field and the external fields?" I would really like to hear an explanation about why this is true, if it is.  (A corollary question that comes to my mind after thinking about this is... What about gravity and mass considering the analogous situation? And the other two forces?)


I was working on Colab and I had to make csv to 2d array. But I had never used python before (I was C user) so I'm not skilled at python list. real = [1, 2] copy = [[0] * 2] * 4  print(copy)  for j in range(1):     for i in range(2):         copy[i][j] = real[i]         print(copy)  I expected [[0, 0], [0, 0], [0, 0], [0, 0]] [[1, 0], [0, 0], [0, 0], [0, 0]] [[1, 0], [2, 0], [0, 0], [0, 0]]  but it works like this [[0, 0], [0, 0], [0, 0], [0, 0]] [[1, 0], [1, 0], [1, 0], [1, 0]] [[2, 0], [2, 0], [2, 0], [2, 0]]  Please help me...

I needed to create a list of lists in Python, so I typed the following: my_list = [[1] * 4] * 3  The list looked like this: [[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]    Then I changed one of the innermost values: my_list[0][0] = 5  Now my list looks like this: [[5, 1, 1, 1], [5, 1, 1, 1], [5, 1, 1, 1]]    which is not what I wanted or expected. Can someone please explain what's going on, and how to get around it?


Hello i have a problem with new update in ubuntu can someone help me  i have this error   ~$ sudo apt-get update Hit:1 http://si.archive.ubuntu.com/ubuntu bionic InRelease Hit:2 http://si.archive.ubuntu.com/ubuntu bionic-updates InRelease              Hit:3 http://si.archive.ubuntu.com/ubuntu bionic-backports InRelease            Get:4 http://security.ubuntu.com/ubuntu bionic-security InRelease [83,2 kB]     Get:5 https://dl.winehq.org/wine-builds/ubuntu bionic InRelease [4689 B]        Err:5 https://dl.winehq.org/wine-builds/ubuntu bionic InRelease                   The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 818A435C5FCBF54A Reading package lists... Done W: GPG error: https://dl.winehq.org/wine-builds/ubuntu bionic InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 818A435C5FCBF54A E: The repository 'https://dl.winehq.org/wine-builds/ubuntu bionic InRelease' is not signed. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.

I added some extra repositories with the Software Sources program. But when I reload the package database, I get an error like the following:     W: GPG error:  trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 8BAF9A6F   I know I can fix it using apt-key in a terminal, according to the official Ubuntu documentation. But I would have liked to do it graphically. Is there a way to do this without using a terminal?


A $ 2.0 kg $ block is being pulled across a frictionless table by a rope with negligible mass at an angle $ \theta=60° $ (from positive direction of $ x $ axis, we have taken horizontal surface of table as $ x $ axis) The tension in the rope is $ 12N $ and causes the box to slide across the table to the right with an acceleration of $ 3.0 m/s² $ But the direction of net force is along the rope. The direction of acceleration isn't. Why is that? There is a net vertical force and that force is vertical component of tension force. The gravitational force is balanced by the normal force (the magnitude of normal force and gravitational force are always same). Why is the acceleration only along horizontal component of tension force. It should be along the the net tension force (along the rope)

A $ 2.0 kg $ box of cucumber extract is being pulled across a frictionless table by a rope at an angle $ \theta=60° $ (from positive direction of $ x $ axis, we have taken horizontal surface of table as $ x $ axis) The tension in the rope is $ 12N $ and causes the box to slide across the table to the right with an acceleration of $ 3.0 m/s² $ But the direction of net force is along the rope. The direction of acceleration isn't. Why is that?


I need to know the computational complexity of the public key encryption (e.g. Paillier), please.  (i.e.Paillier in his paper mentions that the computational complexity of most of public key encryptions is $O(n^3)$, but is not clear to me why)

I want to calculate the time complexity of two encryption and decryption algorithms.  The first one (RSA-like) has the encryption  $$ C := M^e \bmod N $$ and decryption  $$ M_P := C^d \bmod N. $$  Assuming $n = \log N$, $m = \log e$ and $k = \log d$, I think they have time complexities $O(n^2 · m)$ and $O(n^2 · k)$, respectively.  Are these two complexities same?  I also have another pair of algorithms, with  $$ C := M · k \bmod N $$ and  $$ M_P := C · k^{-1} \bmod N.$$  How does the calculation of the modular inverse $k^{-1} \bmod N$ contribute to the time complexity?


I have had my 70d for about 2 months. I had the wifi function set up and it was working fine. This past weekend it asked for me to re-enter my password. I have no idea why I used as my password. How do I go about retrieving of resetting it?  Thanks!

When I go to the WiFi Settings in Camera (Canon 70D) all I see is:  Connection:   Exit Confirm Set Error Details (greyed out)   I can't recall the password or find any way to reset it. Some I found () say the Camera should say Infrastructure mode. Inside the Confirm Settings I can see on page 3 it shows:     Connect'n method: Camera access point mode   But again I see no way to change this.  On my Smartphone EOS Remote app there's a Connection Guide with completely different menus from what I'm seeing on the Camera.  Any idea how I can reset the WiFi Name and Password on the Canon 70D?


I created 12 partitions from July 2017 through July 2018 and didn't leave an empty partition at the end. Hence, am having a hard time adding new partitions using the split function. I even tried switching the oldest partition to a staging table but "split range" is taking a very long time to execute. The goal of this project was to reuse the old partitions by archiving oldest partition to another table but I am not able to use the switch function as it's taking a very long time.  Please advise so I can fix this issue. Here are the scripts:  CREATE PARTITION FUNCTION APITPartFunc AS RANGE LEFT FOR VALUES (     '2018-01-31T00:00:00'     ,N'2018-02-28T00:00:00'     ,N'2018-03-31T00:00:00'     ,N'2018-04-30T00:00:00'     ,N'2018-05-31T00:00:00'     ,N'2018-06-30T00:00:00'     ,N'2018-07-31T00:00:00'     ,N'2018-08-31T00:00:00'     ,N'2018-09-30T00:00:00'     ,N'2018-10-31T00:00:00'     ,N'2018-11-30T00:00:00'     ,N'2018-12-31T00:00:00'     )  CREATE PARTITION SCHEME [APITScheme] AS PARTITION [APITPartFunc] TO (     [ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     )      CREATE TABLE [dbo].[test] (     [id] [bigint] IDENTITY(1, 1) NOT NULL     ,[user_id] [uniqueidentifier] NOT NULL     ,[client_id] [smallint] NOT NULL     ,[api_tracking_type_id] [smallint] NOT NULL     ,[dt] [datetime] NOT NULL     ,[event_data] VARCHAR NULL     ,[entity_id] VARCHAR NULL     ) ON [APITPartScheme] (dt) GO  ALTER TABLE [dbo].[test] ADD CONSTRAINT [PK_test_id_dt] PRIMARY KEY CLUSTERED (     [id] ASC     ,[dt]     )     WITH (             PAD_INDEX = OFF             ,STATISTICS_NORECOMPUTE = OFF             ,IGNORE_DUP_KEY = OFF             ,ALLOW_ROW_LOCKS = ON             ,ALLOW_PAGE_LOCKS = ON             ) ON APITPartScheme  --I was trying to add an empty partition by  ALTER TABLE test switch PARTITION 13 TO teststaging PARTITION 13  ALTER PARTITION scheme apitpartscheme NEXT used apitpart13  ALTER PARTITION FUNCTION apitpartfunction () spit range ('2018-08-04')  ALTER TABLE teststaging switch PARTITION 13 TO test PARTITION 13 --this would be after split works but the above script took forever so I stopped it.

I have a SQL Server table that contains over 20 billion rows, with 13 billion rows in the last partition.  The table is currently partitioned 6 ways by a "Time" field:  2011 2012 2013 2014 2015 2016/2017/2018   The 2016/2017/2018 partition needs to be split into their own partitions so there is a 2016, 2017, 2018 partition.    How can this be done and in the process avoiding a massive log file growth? The database is in Simple Recovery and currently each partition is in a separate file group on its own set of disks.   CREATE TABLE [dbo].[Log](        [RefNo] [nchar](7) NOT NULL,        [DevID] [nvarchar](7) NOT NULL,        [Time] [datetime] NOT NULL,        [summary] [float] NULL,        [staging] [float] NULL,        [position] [float] NULL,  CONSTRAINT [PK_Log] PRIMARY KEY CLUSTERED  (        [RefNo] ASC,        [DevID] ASC,        [Time] ASC  )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = ON, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, FILLFACTOR = 96)  )


#include <iostream> using namespace std;  int main() {     long long a = 3400000000000000000;     float b = 3400000000000000000;     double c = 3400000015362424832;      if (a == b && b == c && c != a) {         cout << "true" << '\n';     } else {         cout << "false" << '\n';     }     return 0; }   i don't know why that if-condition is true.... According to Syllogism, this condition is false. i think the reason is C++ operator principle... but i cant search this problem...

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


Let $\{f_n\}$ be a sequence of integrable functions on $E$ for which $f_n$ converges to $f$ a.e. on $E$, and $f$ is integrable over $E$. Show that if $\lim_{n\rightarrow\infty}\int_E|f_n|=\int_E|f|$ then $\int_E|f-f_n|\rightarrow 0$.  So I feel like this should be really obvious, but I'm having a hard time proving it. I'd appreciate some advice! The details are what get me!

I'm reading Real Analysis by Royden 4th Edition.  The entire problem statement is:  Let $\{f_n\}_{n=1}^\infty$ be a sequence of integrable functions on $E$ for which $f_n\to f$ pointwise a.e. on $E$ and $f$ is integrable over $E$. Show that $\int_E |f_n-f|\to0 \iff \lim\limits_{n\to\infty}\int_E|f_n|=\int_E|f|.$  My attempt at the proof is:  $(\Longrightarrow)$ Suppose $\int_E|f_n-f|\to0$ and let $\varepsilon>0$ be given. Then there exists an $N>0$ such that if $n\geq N$ then $|\int_E|f_n-f||<\varepsilon.$ Consider $$|\int_E|f_n|-\int_E|f||=|\int_E(|f_n|-|f|)|\leq|\int_E|f_n-f||<\varepsilon.$$ Thus, $\int_E|f_n|\to\int_E|f|.$   $(\Longleftarrow)$ Suppose now that $\int_E|f_n|\to\int_E|f|.$ Let $h_n=|f_n-f|$ and $g_n=|f_n|+|f|$. Then $h_n\to0$ pointwise a.e. on $E$ and $g_n\to2|f|$ pointwise a.e. on $E$. Moreover, since each $f_n$ and $f$ are integrable $\int_E g_n=\int_E|f_n|+|f|\to2\int_E|f|.$ Thus, by the General Lebesgue Dominated Convergence Theorem, $\int_E|f_n-f|\to\int_E0=0.$  I'm pretty sure I got this one down, but I was wondering if it was okay for $g_n$ to depend on $f$ or $f_n$ or does it need to be independent of them?  Thanks for any help or feedback!


I'm aware of the concept of overfitting in Machine Learning. The main advice for dealing with it, usually is regularization.   Is there other practical advice to avoid overfitting?

I'm training a neural network and the training loss decreases, but the validation loss doesn't, or it decreases much less than what I would expect, based on references or experiments with very similar architectures and data. How can I fix this?    As for question        to which this question is inspired, the question is intentionally left general so that other questions about how to reduce the generalization error of a neural network down to a level which has been proved to be attainable, can be closed as duplicates of this one.  See also dedicated thread on Meta:


The given graph is connected but not necessarily bipartite. Please describe the complete approach with useful links , I read stuff related to augmenting paths but could not comprehend well. An O(VE) approach will be good for me . Though i would prefer O(V^2) approach (if it is known)

Given a graph $G$, we need to find the cardinality of the largest set of vertices so that each of them are present in every maximum matching possible.   Is there a solution beside the obvious remove each vertex and find the maximum matching to see it reduces?


I have problem with getting p value from my mixed model, library(lme4)  DWR<-lmer(DWRm2~Growth.stage+Se.application+Growth.stage:Se.application+(1|Block),data=Sub1) summary(DWR)   before I used this model and I got p value with summary my model but now I can't get it, I have just t value

I use lme4 in R to fit the mixed model  lmer(value~status+(1|experiment)))   where value is continuous, status and experiment are factors, and I get  Linear mixed model fit by REML  Formula: value ~ status + (1 | experiment)    AIC   BIC logLik deviance REMLdev  29.1 46.98 -9.548    5.911    19.1 Random effects:  Groups     Name        Variance Std.Dev.  experiment (Intercept) 0.065526 0.25598   Residual               0.053029 0.23028  Number of obs: 264, groups: experiment, 10  Fixed effects:             Estimate Std. Error t value (Intercept)  2.78004    0.08448   32.91 statusD      0.20493    0.03389    6.05 statusR      0.88690    0.03583   24.76  Correlation of Fixed Effects:         (Intr) statsD statusD -0.204        statusR -0.193  0.476   How can I know that the effect of status is significant? R reports only $t$-values and not $p$-values.


I'm trying to move a folder into another folder in terminal, but when I enter this line:  mv South_America /North_America   South_America just completely disappears. It didn't move into the North_America folder? or go into my trash.   How do I move a folder?

I am a novice user and I am trying to install Oracle Java. The process calls for me to access /usr/local/java, but here is the problem. I get as far as /usr/local, then this is the message I get:  leonard@leonard-MT6452:/usr/local$ dir bin  etc  games  include  java  lib  man  sbin  share  src  leonard@leonard-MT6452:/usr/local$ cd /java/ bash: cd: /java/: No such file or directory  leonard@leonard-MT6452:/usr/local$ rm -r ~/java rm: cannot remove ‘/home/leonard/java’: No such file or directory   Help?


Ok, here's the idea. This isn't really connected to what is usually referred to as 'quantum teleportation', but assuming that all particles can tunnel to a different location given the right circumstances, shouldn't it be possible that entities made of particles may also be able to do the same thing.  This is partly inspired by the deja vu scene in the Matrix, where Neo sees the cat appear at the doorway twice; I was thinking that the cat could have 'tunnelled' back to its original position in this way.  I know that, if there's any probability of this occurring at all it'd be minute, and I'd also like to know what - if any - role the exclusion principle plays in this. Would the particles need to be of the same energy, or would that not matter? Also, what would need to be the coherence/decoherence of the 'system' tunnelling to a new location.   I'd also be interested in trying to tease out any connections with relativity. The idea being that while tunnelling may be possible, in a wormhole-like fashion, because of it's mass-energy (that of a cat), it'd only be able to tunnel a short distance (more than likely), a few feet say.

Could any form of matter teleportation every really happen?  If so, what form would it take? Some science-fiction talks about literally sending the atoms from one location to another; others talk of creating a duplicate and destroying the original.  Question originally added .  Update: there are a couple of comments asking me to specify what I mean by teleportation. I'm talking about stuff of Star Trek - taking an object or person and transporting them almost instantly across great distances (thousands of KMs) by:   breaking them up at the atomic (or smaller) level transporting those atomic components (or the information, "recipe" to recreate) and (re-)assembling at the new location.


Using an exam class, Is there a way to keep questions on one page.  Particularly with multiple choice questions, is there a way to keep a page break from occurring in the middle of the question?

I'd like to prevent page breaks between a question and its answer choices in the Exam class. There's a good solution to the problem of how to prevent page breaks within the answer choices , but that question did not address how to prevent breaks between the question and the answers.


Misc Situation:  -Server login is obtained by hacker, hacker places malicious brute force file in /hacked/bruteforce/  -Server password is then changed, hacker can still run script by navigating to their file on the server which will run upon their request (I am assuming?)  Question:  Would a combination of changing the server login password as well as adding a password protected .htaccess file to / stop the hacker in their tracks? Or can an .htaccess still be avoided in terms of rerunning the hacker's script?  I am very new to server security but am eager to learn anything and everything anyone can tell me! I highly appreciate any and all advice. Any recommended knowledge resources would also be fully utilised!  OUR SITUATION:  Here is the information provided to us by our host.  your Server/Customer with the IP: * has attacked one of our servers/partners. The attackers used the method/service: bruteforcelogin on: Sat, 14 Nov 2015 -exact time provided here-. The time listed is from the server-time of the Blocklist-user who submitted the report. The attack was reported to the Blocklist.de-System on: Sun, 15 Nov 2015 -exact time provided here-  Here is some more:  Lines containing IP-ip here-: NOT SORTED (from many different Machines)! DESTINATION-IP: -ip info here-  DESTINATION-IPs: -ip info here-  -ip here- - - [14/Nov/2015:-exact time provided here-] "POST wp-login.php HTTP/1.1" 200 4366 "referer-domain.tld" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0"  -ip here- - - [14/Nov/2015:-exact time provided here-] "POST /wp-login.php .... truncated .... 0"POST wp-login.php HTTP/1.1" 200 4366 "referer-domain.tld" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0"  -ip here- - - [14/Nov/2015:-exact time provided here-] "POST wp-login.php HTTP/1.1" 200 5117 "referer-domain.tld" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0"  Regards, Jay.

This is a  about Server Security - Responding to Breach Events (Hacking)   See Also:                  Canonical Version I suspect that one or more of my servers is compromised by a hacker, virus, or other mechanism:   What are my first steps? When I arrive on site should I disconnect the server, preserve "evidence", are there other initial considerations? How do I go about getting services back online? How do I prevent the same thing from happening immediately again? Are there best practices or methodologies for learning from this incident? If I wanted to put a Incident Response Plan together, where would I start? Should this be part of my Disaster Recovery or Business Continuity Planning?   Original Version       2011.01.02 - I'm on my way into work at 9.30 p.m. on a Sunday because our server has been compromised somehow and was resulting in a    attack on our provider. The servers access to the Internet   has been shut down which means over 5-600 of our clients sites are now   down. Now this could be an FTP hack, or some weakness in code   somewhere. I'm not sure till I get there.      How can I track this down quickly? We're in for a whole lot of   litigation if I don't get the server back up ASAP. Any help is   appreciated. We are running Open SUSE 11.0.            2011.01.03 - Thanks to everyone for your help. Luckily I WASN'T the only person responsible for this server, just the nearest. We managed   to resolve this problem, although it may not apply to many others in a   different situation. I'll detail what we did.      We unplugged the server from the net. It was performing (attempting to   perform) a Denial Of Service attack on another server in Indonesia,   and the guilty party was also based there.      We firstly tried to identify where on the server this was coming from,   considering we have over 500 sites on the server, we expected to be   moonlighting for some time. However, with SSH access still, we ran a   command to find all files edited or created in the time the attacks   started. Luckily, the offending file was created over the winter   holidays which meant that not many other files were created on the   server at that time.      We were then able to identify the offending file which was inside the   uploaded images folder within a  website.      After a short cigarette break we concluded that, due to the files   location, it must have been uploaded via a file upload facility that   was inadequetly secured. After some googling, we found that there was   a security vulnerability that allowed files to be uploaded, within the   ZenCart admin panel, for a picture for a record company. (The section   that it never really even used), posting this form just uploaded any   file, it did not check the extension of the file, and didn't even   check to see if the user was logged in.      This meant that any files could be uploaded, including a PHP file for   the attack. We secured the vulnerability with ZenCart on the infected   site, and removed the offending files.      The job was done, and I was home for 2 a.m.            The Moral   - Always apply security patches for ZenCart, or any other CMS system for that matter. As when security updates are released, the whole   world is made aware of the vulnerability.   - Always do backups, and backup your backups.   - Employ or arrange for someone that will be there in times like these. To prevent anyone from relying on a panicy post on Server   Fault.


I'm trying to upgrade Ubuntu 13.04 to 13.10.  I have executed the terminal command :  sudo apt-get dist-upgrade  I've got the following error :  dpkg: error processing /var/cache/apt/archives/linux-image-3.8.0-35-generic_3.8.0-35.52~precise1_amd64.deb (--unpack): trying to overwrite '/lib/modules/3.8.0-35-generic/kernel/mm/hwpoison-inject.ko', which is also in package linux-image-extra-3.8.0-35-generic 3.8.0-35.50 dpkg-deb: error: subprocess paste was killed by signal (Broken pipe) Examining /etc/kernel/postrm.d . run-parts: executing /etc/kernel/postrm.d/initramfs-tools 3.8.0-35-generic /boot/vmlinuz-3.8.0-35-generic run-parts: executing /etc/kernel/postrm.d/zz-update-grub 3.8.0-35-generic /boot/vmlinuz-3.8.0-35-generic Errors were encountered while processing: /var/cache/apt/archives/linux-image-3.8.0-35-generic_3.8.0-35.52~precise1_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)

What are the different ways I can use to upgrade Ubuntu from one release to another?


I need to install lxde (only vanilla one)  in Ubuntu 14.04 64bit system. It has no internet access so I have to download lxde and install it offline. How do I do it. Since typing  sudo apt-get install lxde wouldn't work.

I have a friend who has got a computer that is not connected to the Internet. Is there any way to install software offline easily?


I am very lost in this, can anyone explain this to me please?   Let $U = \{1,2,3,4,5,6,7,8,9,10,11,12\}$, and $f$ be a function from $U$ into $U$. Finally, let $F : P(U) → P(U)$ be the function defined by $F(X) = \{f(x)\> |\> x \in X\}$ For instance, if $f(x) = 13 − x$, and $X = \{1,3,4,7\}$, then $F(X) = \{f(1),f(3),f(4),f(7)\} = \{12, 10, 9, 6\}$.  a. Prove that for every two subsets $A$, $B$ of $U$, we have $F(A ∩ B) \subseteq F(A) ∩ F(B)$.  b. Give an example that shows that $F(A- B)$ is not necessarily a subset of $F(A)- F(B)$.

Let $U = \{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12\}$, and $f$ be a function from $U$ into $U$.   Finally, let $F : P(U) \to P(U)$ be the function defined by  $$F(X) = \{f(x) | x \in X\}$$  For instance, if $f(x) = 13 − x$, and $X = ${1, 3, 4, 7}, then $$F(X) = \{f(1), f(3), f(4), f(7)\} = \{12, 10, 9, 6\}$$  Show that $F(A−B)$ is not necessarily a subset of $F(A)−F(B)$.    I am having trouble showing an example. Let's say:  $A = \{1,3\} , B = \{2,3\}$  $F(A) = \{f(1),f(2)\} = \{12,11\}$  $F(B) =\{f(2),f(3)\} = \{11,10\}$  Now, $F(A-B) = \{12,10\}$  $F(A)-F(B) = \{12\}$.  Hence, $\{12,10\} \nsubseteq \{12\}$ <-- hmm..  By definition if $A \nsubseteq B$, there exist an $x \in A$ such that $x \notin B$. From my example, we have $x=10 \in A $ but $\notin B$. Is that sufficient?     I'm confused between the difference of $F(A-B)$ and $F(A)-F(B)$.


To create window holes I used the boolean modifier. It works well 90% of the time, but every now and then it creates these lines in the surface of the solid, visible even though I turn off the wireframe view mode. I tried dissolve Edge, but in edit mode those oblique lines are not seen if I select the boolean solid to subtract.

So, I'm working on a control station that has buttons. It is a one-mesh creation, that means, I don't want to create buttons and things like that separated from the main mesh, but as you can see, I have problems. I would like to make the highlighted parts to be one with the main part around them. I've tried everything, and I have this problem on multiple creations. Any idea?  Update: I've added another example of the problem. I want them to be one face, instead of two. (2nd picture)


If $z_1,z_2,z_3,z_4 \in \mathbb{C}$ satisfy $z_1 + z_2 + z_3 + z_4  =  0$ and $|z_1|^2 + |z_2|^2 + |z_3|^2 + |z_4|^2 = 1$, then the least value of $|z_1 - z_2|^2 + |z_1 - z_4|^2 + |z_2 - z_3|^2 + |z_3 -  z_4|^2$ is $2$.   I solved this by taking two of the values to be $\frac{1}{2}$ and other two as $-\frac{1}{2}$. But I couldn't prove this in an efficient manner.


note to future users who come across this question  this question has been tagged as a possible duplicate of          That question is about the whole process of having the OS apt-get update and apt-get upgrade packages automatically - not the popup manager window. However this question is a duplicate of this:      It turns out the update manager popup cannot be managed through apt's configuration files, it acts as an independent daemon and needs to be managed separately.    Every morning when I log into my install of Ubuntu 16.04.1 I get this:    I don't want this box to appear, as I would rather handle the updating process manually.    I have the following configuration:  file: /etc/apt/conf.d/10periodic  APT::Periodic::Update-Package-Lists "0"; APT::Periodic::Download-Upgradeable-Packages "0"; APT::Periodic::AutocleanInterval "0"; // Try and turn off autoupating APT::Periodic::Enable "0";   file: /etc/apt/conf.d/20auto-upgrades  APT::Periodic::Update-Package-Lists "0"; APT::Periodic::Unattended-Upgrade "0";   My attempt to discover what is responsible for firing the automatic update system  man apt.conf states:     PERIODIC AND ARCHIVES OPTIONS          APT::Periodic and APT::Archives groups of options configure behavior of          apt periodic updates, which is done by the /etc/cron.daily/apt script.          See the top of this script for the brief documentation of these          options.   It looks like this has been replaced by /etc/cron.daily/apt-compat which mixes times abit so everyones Ubuntu doesn't try update at once then it calls:  /usr/lib/apt/apt.systemd.daily   /usr/lib/apt/apt.systemd.daily is a shell script that starts with a comment:     This file understands the following apt configuration variables:    Values here are the default.    Create /etc/apt/apt.conf.d/10periodic file to set your preference.   so following this advice I entered this      // Try and turn off autoupating     APT::Periodic::Enable "0";   into /etc/apt/apt.conf.d/10periodic as you can see from my config listing above. yet I am still getting the notification...  Possible solutions I can think of   the comment // Try and turn off autoupating may be causing a parse error of the config file, causing apt to ignore the entire file?  unlinking or commenting out /etc/cron.daily/apt-compat ?   How can I disable the update notifier box?

I want to be sure if automatic updates are enabled on Ubuntu 12.04 server.   How exactly can I check this?   And how can I disable automatic updates if it's enabled?


I would like to search for a file with GUI. I have 2 files :  /world/europe/georgia_and-its_capital-tbilisi.info /world/north_americas/usa/georgia_state_capital.info ;   A search for:  find /world -name "*gia*capit*"   -- brings up the two files.  How to conduct this search with Nautilus' search or any alternate suggestion? I use Ubuntu 12.04 LTS.  And Applications | Search is not available on it.

On the command line I regularly use locate, or more often a locate x | grep y pattern to find a file I know exists but can't find!  I'd like something that did this quickly in the GUI. Can't find it if it's there.  Here's my confusion   In the applications/overview I can see Search and Indexing. This seems to be a configuration tool. But if this is a server, I can't find a client. In applications I find Nepomuk File Indexing -- I think this is a KDE thing? Ditto, no client? I've installed tracker. This is a strange mix of powerful and unreliable/limited. e.g. it doesn't find files like locate does (returns no results where locate returns 96 results), but is will unpack every tag I've added to my photos! And you can't limit by folder for a quick search within a folder. The old Gnome 2 Search for files... thing is not in the Accessories menu anymore.   I feel that this is basic/core-level functionality and I can't help feeling I'm missing something obvious.


Where could I find the exe/process/dll that handles this colored tray icon of Bluetooth tray icon.    I am very customized person, so I want to customize it, break it open and replace those resources with my redesigned ones to make that Bluetooth icon in line with that other Windows 10 tray icons. Where I could find it? Thanks

Where could I find the exe/process/dll that handles this pesky . I am very customized person, so I want to customize it, break it open and replace those resources with my redesigned ones to make that Bluetooth icon in line with that other Windows 10 tray icons Tell me where I could find it? Thanks


everyone. I am new to ubuntu. I was just wondering what is the diffrence between sudo apt-get update and sudo apt-get upgrade

I am wondering what sudo apt-get update does?  What does it update?


In my Microcontroller there exist UART ports. But I have not understood well how they can be used. Can I use them for TTL or RS232 communication? And would it be also possible for me to use them to receive DVP signal from CMOS image sensor like OV7670?   Thank you

I'm taking an EdX class in embedded systems and I'm having a little trouble fully grasping what a UART is.  The UART has been used as a means to an end, so it hasn't been described well yet.  A UART seems to be a communication system centered around a hardware component (also referred to as the UART?).  Presumably they are controlled by standardized code libraries?  We've been provided with some functions that control the UART, but it is not clear whether this is part of a standard library or written by the educators:  UART_Init();    // initialize UART for printing   It is not yet clear to me whether UARTs are standard on all microcontrollers, or specific to the device we're using.  It seems that UARTs have a wide range of I/O capabilities, but what they are, and how widely they are used, is not clear to me.  A beginner-level explanation that can briefly describe and connect any/all of these threads together would rock:   UART hardware UART software interface UART's place in the wider electronics world  overview of usage & capability of UART


I've read that too many reflections can cause these artifacts, but I couldn't find a solution to remove them. My sampling was set to 512.

I often use Cycles' built in Glass BSDF shader to achieve realistic refraction effects, but in many cases, it seems that Cycles' glass caustics creates an unfortunately large number of fireflies (pixels that are abnormally bright relative to their surroundings). In some models of mine, even when I render for 3000 or more samples/pixel, my final image is still covered in fireflies. While I can improve this in many cases by increasing the total amount of light available in the scene, this loses a lot of the potency of the refractive effects I'm looking for, especially in scenes with low light levels.  So my question is, how can I reduce the amount of fireflies while using Cycles' caustics without sacrificing the quality of the refractive effects?  Note: I am aware that Cycles' caustics will perform much better once Cycles has full support for bidirectional path-tracing, but it looks unlikely that that will become , unfortunately.


The new top nav-bar helped me navigate to the fancy  again, but the example question caught my eye.  The example shows that the question was answered a year before it was asked.    Minor issue, I know.  But could we fix this, please?

Are the questions in the about page taken from real posts? If not, who designs them?  Particularly, why does this specific answer have a date from before the question was asked?


Example: You use Quicken Spell to cast a leveled spell or cantrip as a Bonus Action, you then use your Action to cast a cantrip along with using Transmute Spell to change the cantrip's damage type. Is this an ok thing to do? LMBC:You're using two meta-magic options on two different spells in one turn.

Can you cast one cantrip, modifying it with "Twinned Spell" (Fire Bolt) to target 2 creatures, and then cast another cantrip as a Bonus Action (Fire Bolt), using "Quickened Spell" to target one of the previous creatures or another creature?


I'm open to pitching in with the code.  The seams between chat and main are bothersome to me.

Being able to join chat rooms from the Android app would be a plus! It would truly make us connected on the go, instead of having to sit down at our desks and open a browser window. This will allow more users to fully utilize the chat system and join events no matter where they are.


Within the Star Wars timeline, we first see Chewbacca in Episode III: The Revenge of the Sith. In it he appears as a full grown adult and seems to have a high status within his community. Then, of course, he appears in the "middle 3" episodes, where he pretty much looks the same.  Now he has appeared in Episode VII: The Force Awakens, still looking as if he hasn't aged. That is a period of over 50 years. How long do Wookiees live, and how do they change as they age?  Canon answers preferred, if possible.

At lunch, my coworkers and I were discussing The Force Awakens, and started questioning Chewbacca's age.  A quick check of  and it says he is possibly about 230 years old as of Episode VII.  Following the  link on that page, Wookieepedia claims that they live to be 400 years old.  Do we know from canon what the average life expectancy of a Wookiee is?


How do you calculate the infinite sum $\sum_{i=1}^{\infty} \frac{\sin(i)}{i}$? According to Wolfram Alpha, the value of the sum is $\frac{\pi - 1}{2}$, but it does not tell me the method by which it gets this result.

Inspired by  (and far more straightforward, I am guessing), Mathematica tells us that $$\sum_{k=1}^{\infty}\dfrac{{\sin(k)}}{k}$$ converges to $\dfrac{\pi-1}{2}$.   Presumably, this can be derived from the similarity of the Leibniz expansion of $\pi$ $$4\sum_{k=1}^{\infty}\dfrac{(-1)^{k+1}}{2k-1}$$to the expansion of $\sin(x)$ as $$\sum_{k=0}^{\infty}\dfrac{(-1)^k}{(2k+1)!}x^{2k+1},$$ but I can't see how...  Could someone please explain how $\dfrac{\pi-1}{2}$ is arrived at?


I have just installed ubuntu 14.04 and when I reboot and remove the media I get the   Gave up waiting for root device. Common problems: -Boot args (cat /proc/cmdline)  -check rootdelay= (did the system wait long enough?)  -Check root= (did the system wait for the right device?) -Missing modules (cat /proc/modules; ls /dev) ALERT ! /Dev/disk/by-uuid/e9399244-24c6-46bd-9786-051806f0f93f does not exist. Dropping to a shell  BusyBox v1.21.1 (Ubuntu 1:1.21.0-1ubuntu1) built-in shell (ash) enter 'help' for a list of built-in commands.  (initramfs)  $ ls -l /dev/disk/by-uuid lrwxrwxrwx 1 10 E411-5D60 -> ../../sda1   lrwxrwxrwx 1 10 e9399244-24c6-46bd-9786-051806f0f93f -> ../../sdb1 lrwxrwxrwx 1 10 df7a3fc6-d2dc-4c85-a445-8bbc02ff7c84 -> ../../sdb5   and I tried the solution found here:  twice...I still get the busybox shell...what can I do from here?

I am using Ubuntu 14.04.  I ran in terminal sudo apt-get update. Then I rebooted the system. And now I see:   ALERT! /dev/disk/by-uuid/xxxxxxxxx does not exist. Dropping to a shell initramfs:_   I can't boot up LIVE Ubuntu from USB flash drive. Yes, I double checked BIOS setup and the USB flash drive is OK and runs on another machine. Right now I am going to buy a  DVD and burn a Live DVD from another laptop.  sudo blkid gives me:   /dev/loop0: TYPE="squashfs"   /dev/sda1: UUID="xxxx" TYPE="ext4"    /dev/sr0: LABEL="Ubuntu 14.04.1 LTS i386" TYPE="iso960"      /etc/fstab has the same UUID="xxxx" and there is a line with:   errors=remount-ro 0      I tried using boot-repair but I still can't log in to Ubuntu.  I don't want to reinstall Ubuntu, because I have a lot of data there.  Do you have any advice how this can be solved?


I recently uninstalled MS Office 2010 on PlayOnLinux and then reinstalled it. However I found that the previous icon is still in the menu as it is shown here:    The same problem also happens with Powerpoint and excel. If I click the previous one, PlayOnLinux will tell me that this app is crashed, however I cound't find these apps inside the PlayOnLinux either.  Any idea?

I installed  (for Windows) using wine but turns out LAN Messenger is also available for linux as well. So..   I uninstalled LAN Messenger from wine. I also removed wine. deleted the .wine directory. after that sudo apt-get autoremove and sudo apt-get autoclean. then I installed LAN Messenger using dpkg -i pkgname.deb and it installed successfully.   The problem is that now I get this in dash:   Any Help is highly appreciated.  [NOTE] I am using ubuntu 12.10


When I was reading the book Because of Winn-Dixie, on page 89 I found a paragraph as follows:     "Oh, lay off her," Dunlap said to Stevie. Then he turned to me. "He don't mean it," he said.   Can anybody tell me why the writer uses "don't" instead of "doesn't"?

I'd like to know how the sentence "That don't impress me much" sounds to a native English speaker.  The phrase is the title of a song by Shania Twain, and to my eyes it contains a clear error. It is obviously intended, and I want to know what was the effect that the author wanted to obtain.  Other examples that come to mind:   “She's got a ticket to ride, but she don't care” — The Beatles “My love don't cost a thing” — Jennifer Lopez “It don't matter” — Akon “She don't care about me” — heard in the Lost series “It Don't Mean a Thing” — a jazz album title “The Sun Don't Lie” — another album title


I want to draw the roots of z^5=1-i.  I am totally novice to latex and really have no idea about drawing. Thanks for helping!

I would like to have the unit circle, centered at the origin, on the Cartesian plane drawn.  The origin is to be marked with a dot and labeled "O" and five dots are to be drawn on the circle, one on the x-axis, and the others at k(2\pi/5) radians from the positive x-axis for each integer 1 \leq k < 5, and they are to be labeled "w_{k}".  Arrows are to be drawn from the origin to each w_{k}, too. One angle is to be drawn and labeled - the one from the positive x-axis to the ray through w_{1}.  I have included some of the code.  It starts with the following commands.  \tikzset{mydot/.style={fill,circle,inner sep=1.5pt}}   Is there a manual that explains each of these commands?  I guess that this is instructing LaTeX how to make the dots indicating the coordinates each time "\mydot" is in the code.  \documentclass{amsart} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsthm} \usepackage{newlfont} \usepackage{mathtools} \usepackage{tikz}  \tikzset{ mydot/.style={   fill,   circle,   inner sep=1.5pt   } }  \begin{document}  \begin{tikzpicture}[>=latex]   % the coordinates of the vertices \coordinate (O) at (0,0); \coordinate (w_{1}) at (\cos(2\pi/5), \sin(2\pi/5));  % the axes \draw[help lines,->] (-1.5,0) -- (1.5,0); \draw[help lines,->] (0,-1.5) -- (0,1.5);  % labelling the vertices \node[mydot,label={below:$O$}] at (O) {}; \node[mydot,label={right:$w_{1} = \bigl(\cos(2\pi/5), \sin(2\pi/5)\bigr)$}] at (w_{1}) {};   % the arcs for the angle \begin{scope}[gray] \draw[->]   (1,0) +(0:0.5cm) arc [radius=1cm,start angle=0,end angle=2\pi/5] node[midway,right] {$2\pi/5$}; \end{scope}  \end{tikzpicture} \end{document}


How  many ways are there to arrange the letters $A$, $A$, $B$, $B$ around a circle? My first go with was is to arrange $4$ objects around a circle with gets us $(4-1)!$ but we have to take care of the inner arrangements of $A$, $A$ and $B$, $B$ which leaves us with $$\frac 6 {2! \cdot 2!}  $$  but that's obviously wrong. I have tried other methods too but they fail to generalize. By counting by hand for both the $2A$'s and $B$'s case and the $3A$'s and $3B$'s case we get the answers $2$ and $4$ respectively (hopefully I didn't make any mistakes counting)   what's wrong with my argument? what's the right method for solving this? how can this be generalized?

what is the total number of distinct arrangements of $n$ oranges and $n$ apples around a round table? I have no idea how to go about.


I'm writing a booklet and I'm facing a problem with the back page. Printing the resulting PDF of the LaTeX project as a booklet often result in a unwanted layout. I mean... to have the back cover in the last booklet page the total number of pages in the book should be divisble by 4. Up to now I'm solving this placing blank pages to match the correct number, I would like to avoid this in a more programmatic way or using some features of LaTeX itself. Up to now I'm using this document class:  \documentclass[dvipsnames,a5paper,twoside,openright,italian,12pt]{memoir}   I'm printing this on A4 paper and folding.  The backpage is defined through this command:  \newcommand{\myback}{%     \cleartoleftpage%     \thispagestyle{empty}%     \begin{center}%         \begin{vplace}[0.7]%             \def\svgwidth{60mm}%             \input{logo_red.pdf_tex}%             %\includegraphics[width = 60mm]{logo_red.png}%         \end{vplace}         \vfill%         {\color{red} \huge \textcopyright~\thedate}%     \end{center} }   and refers to another custom command:  \newcommand*\cleartoleftpage{%     \clearpage     \ifodd\value{page}\hbox{}\newpage\fi }   that works fine on books since it forces backpage to be on an even page.  How can I modify such condition to fit my current needs?  BTW I'm not using the booklet package (but as long as I can see there are not specific functions to create a back cover in the last page).

I postprocess my PDF produced from my LaTeX-document through pdfbook and want to have the last page appear on the back cover. Thus, I need to have as many pages inserted before the last page so it gets onto a page number divisible by 4.  I looked to  question but    that seems complicated, and I do not want to add additional packages if I can do without them.   Therefore my idea would be to add blank pages before the last page, until it becomes 3 modulo 4.  Pseudocode:   regular document text if {current-page} % 4 != 3: \newpage if {current-page} % 4 != 3: \newpage if {current-page} % 4 != 3: \newpage content of last page   Is that feasible? How to code this in LaTeX?


I had been using wsl2 on the Windows Insider preview for a while, but was getting fed up with programs I needed to work breaking due to it being a dev build. As a result I decided to switch to a dual boot system so I could use a stable Windows version for the programs I need which are Windows exclusive and Ubuntu for my other requirements. After getting Ubuntu installed, I am unable to connect to ethernet or Wi-Fi. After running sudo lshw -C network and ls /sys/class/net I get the following results(typed due to inability to post imgs, formatting may be weird as a result): *-network UNCLAIMED            description: Ethernet controller      product: RTL8125 2.5GbE Controller      vendor: Realtek Semiconductor Co., Ltd.      physical id: 0      bus info: pci@0000:07:00.0      version: 05      width: 64 bits      clock: 33MHz      capabilities: pm msi pciexpress msix vpd cap_list      configuration: latency=0      resources: ioport:f000(size=256) memory:fc510000-fc513fff  lo In case it's relevant, while setting up the installation I only explicitly set the / and /home partitions as recommended by the guide I was following. Given I have no way of updating or upgrading the system due to the lack of connection I'm totally lost as to how to proceed.

So I did a fresh install of Ubuntu 20.04 on a computer with the new RTL8125B Realtek network card and I cannot get the network to work. I was very suprised since this is supposed to be the new feature of the 5.4 kernel (I have 5.4.0-26-generic installed). Does anyone have any idea on how to get it working? Thank you. $ lspci -knn | grep Eth -A3 06:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8125 2.5GbE Controller [10ec:8125] (rev 04) Subsystem: ASUSTeK Computer Inc. RTL8125 2.5GbE Controller [1043:87d7] Kernel modules: r8169 07:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/570X/580/580X/590] [1002:67df] (rev e7)  $ dmesg | grep -i r8169 [    0.911236] r8169 0000:06:00.0: unknown chip XID 641


Please, consider the following code:  public static void main(String[] args) {     String value="abc";     value="";     if(value==""){         System.out.println("blank "+value);     } }   I do not understand why if(value=="") is returning as false.

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


Font size in content areas is too small to be comfy for me. Please make it customisable.   Functional areas are ok because I don't have to actually read them to know what's there.

Can you add a setting for choosing font size in iPhone mobile app?   It's hard to read questions.


So given a deBroglie wavelength 1.8nm and the equations E=hf and E=1/2mv^2  you can get v = 2h/m*(1.8*10^-9)  but this is 2 times the expected value. Wherever I look online people use the momentum p instead to calculate the speed v. But I don't understand why the working above using those two equations gives you an incorrect answer. Obviously I must be missing something here, I was thinking that perhaps more of the energy is stored in the neutron and isn't actually stored as kinetic energy.  Any help is appreciated.

I am studying quantum physics and there is something I don't understand:   I know that for any particle $E=hf$ (Einstein relation) and  $v=\lambda f$ ($v$ is the speed of the particle). I also know that the kinetic energy is $E_k=\frac{mv^2}{2}$.    Solving those 3 equations for $\lambda$:  $$h\frac{v}{\lambda}=\frac{mv^2}{2},$$ I finally find $$\lambda=\frac{2h}{mv}=\frac{2h}{p},$$ which is not consistent with the De Broglie relation $$\lambda=\frac{h}{p}.$$ Where am I wrong in my development?


In a few weeks I will be using train 305 to go from Mongolia to Irkutsk. This train leaves on a Tuesday and arrives at Irkutsk on Wednesday. According to Russian Railways, this train arrives the border point at Naushki at 23:55, still Tuesday, and stays there a couple of hours.   The thing is, my visa is valid from Wednesday. I know that technically if I really arrive at 23:55 my visa will not yet be valid, but by the time the guards take my passport it would probably be Wednesday already.  Maybe a better question would be if guards will stamp the visa with the Tuesday date or Wednesday, since it will in fact be Wednesday. But only people that have traveled on that particular train will know.  Anyone that has traveled on that train or in a similar situation could tell me what chances I have to be taken off the train?  EDIT: This is the timetable from Russian Railways. Times until Sukhbaatar are local. From Naushki times are Moscow time (add 5h for local).

A friend of mine is taking the Train from Finland to Russia. She has now paid and sent the Tourist visa application, with the requested validity being from 3 to 16 August.  Now she's considering entering the evening before, so I would like to ask the following:  The Train she wants to take arrives at Vyborg (first Russian station) on 2 August at 22:22, then St Petersburg at 23:27. The Russian border guards board the train at Vyborg and do the checks while the Train is travelling between the stations, so sometime between 22:30-23:00  If the visa validity starts on 3 August, and she is checked at 22:30-23:00 the evening before, what would happen? Are they very strict about the starting date if it's within 1-1.5 hours, and how bad would the consequences be?  Although they do the check while travelling between Vyborg and St Petersburg, could they simply wait until arrival in St Petersburg, then hold her in custody for 30 minutes and then stamp her in?


What is the smartest way, before selling a mobile phone, to be sure that no one will be able to access my data?  In my case we are talking about an LG G4.

I have two phones, the  and , both using Android 2.1, and I intend to sell them in the near future.  Before selling (just like before selling a HDD), I want to wipe all the personal DATA from the phones.   Question: Does a "factory reset" (from the Android phones "menu") surely wipe all the personal data? Or will there be something left to use? (ex.: contact list, Gmail password, etc.?)


Which sentence is grammatically correct?   I don't know why did I write it I don't know why I did write it

If the original question is "What time is it?" and I want to communicate it to another person, are these Embedded Questions OK?        I don't know what time is it.       or        I didn't know what time was it. (if communicated later)


What different between [[0] * n for i in range(n)] and [[0] * n] * n]  I have this code:  def matrix_decomposition(a):     n = len(a)     b = [[0] * n for i in range(n)]     c = [[0] * n for i in range(n)]     for j in range(0, n):         b[j][0] = a[j][0]         c[0][j] = a[0][j]/b[0][0]     for i in range(1, n):         for j in range(1, i+1):             b[i][j] = a[i][j] - sum(b[i][k]*c[k][j] for k in range(0, i))         for j in range(i, n):             c[i][j] = (a[i][j] - sum(b[i][k]*c[k][j] for k in range(0, i))) / b[i][i]     return b, c   and if I replace [[0] * n for i in range(n)] on [[0] * n] * n I get this error:     Traceback (most recent call last): File   "C:/Users/Noctus/PycharmProjects/lab3/matrix.py", line 46, in    [7, 22, 70, 149] File   "C:/Users/Noctus/PycharmProjects/lab3/matrix.py", line 27, in   matrix_decomposition c[i][j] = (a[i][j] - sum(b[i][k]*c[k][j] for k in   range(0, i))) / b[i][i] ZeroDivisionError: float division by zero   in 46 line I have:  b, c = matrix_decomposition([         [1, 2, 3, 4],         [2, 7, 21, 26],         [4, 13, 43, 88],         [7, 22, 70, 149] ])

I needed to create a list of lists in Python, so I typed the following: my_list = [[1] * 4] * 3  The list looked like this: [[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]    Then I changed one of the innermost values: my_list[0][0] = 5  Now my list looks like this: [[5, 1, 1, 1], [5, 1, 1, 1], [5, 1, 1, 1]]    which is not what I wanted or expected. Can someone please explain what's going on, and how to get around it?


Working for my client, Google has indexed for some time the index page of my website example.com. If a search is done for "example company" however, Google returns no results. If the search is done for "example", or "example company", or example company 314 (part of the business address), Google returns the index page in search results.   I have also noticed examples identical to mine are returned in searches as the first listing.  My code to text ratio is 38%. My maximum number of keyword repetitions in the body text is 5. My description text contains 4 identical keywords, fences. The title text is good. The site is mobile friendly across the website (I used Bootstrap). Page speed is great for desktop about 90+ and mobile about 75+, per google page speed. GTMetrix gives me a 97 and 91 Yslow. The site is optimized as much as it can be and be functional. I can find no place where I am spamming keywords. I Have no doorway redirects or any other prohibited practice. I have a good sitemap.xml file, my robots.txt isn't blocking anything.   Basically, I can't find anything wrong.  Oh, and a P.S., Bing, Yahoo, plus all the other engines bring up the index page with a standard search using the company name.  P.P.S., My domain was purchased from Google domains, I have a Google+ business page, and Google Analytics. Oddly, Google Analytics claims the index page is at position 9.4. Unbelievable.

I have a website setup through WordPress on a custom domain that I control. It is registered in the Google Webmaster Tools, and pages will show up on Google, but not in the order I'd like.  I am working with others in the organization to include links on their websites to this main one to try to help. I have the Yoast SEO plugin installed, and many pages show the green circle, indicating great SEO on the pages. I even have the sitemap loaded to Google.  When I search for the company directly, it's not even on the front page. If I search for the company with no spaces in its name, then it shows up near the bottom of the first page. What can I do to increase its recognition based on its initials, or at least the company name spelled out properly with spaces?