Note: this is an alternative proposal to      The manner in which comments are moved to chat on "noisy" websites is   incredibly disruptive.  It goes something like this:         Several comments are moved to chat by a moderator and linked to the chat room.   More comments are written under the post.   Moderator returns and deletes all of the new comments, leaving a new comment "Comments cannot be moved to chat twice.  Any further   comments will be deleted."         The workflow for moving comments to chat is very haphazard.  You never   know when the "would you like to move this conversation to chat" link   will appear, and when it does, it doesn't actually move the   comments, nor does it "move" all of them.  This is also true of   moderator chat conversions.      The policy of deleting further comments because they can't be moved   into the chatroom is just terrible in so many ways.   Several mods have expressed an interest in retaining better control over this process.  Therefore, I suggest that we allow diamond moderators to move new comments to an existing "move to chat" chatroom (preserving time order).

Moderators can move comments to a chat room associated with the post, and now we don't even have to wait for 20 comments to be posted in a short period of time -- we can do this at any time .  This is great; it gives people a place to have that tangential discussion that might be valuable but isn't about the post any more and doesn't belong on the main site.  Here's the problem: we move comments to chat, which leaves an auto-generated comment saying "comments have been moved to chat (link)".  And then some people continue the discussion in chat but other people .  Sometimes there are so many new comments that the "moved to chat" comment gets buried so people don't even notice.  (I've had several cases where dozens of new comments came in after a move to chat.)  When more (non-clarification-seeking) comments appear after a chat migration, our choices are:   delete the comments (failure to follow directions), but users think this is mean and it's also tedious to do (have to either delete them individually or purge and then dig through the big pile to undelete the "moved to chat" comment buried in the middle) leave it alone, but then we're being inconsistent (why did those have to move but not these?) and thus inviting the unwanted behavior hand-copy them into the chat room, which is a lot to ask of moderators, especially to serve people who didn't take the initial hint (translation: no we are not going to do that)   The "move comments to chat" feature is single-use; once it's been used on a post it's grayed out on the menu, presumably because bad things would happen if it tried to create the same chat room a second time.  Would it be possible for that option to remain (optionally renamed "add comments to chat" if you think that's valuable), with later invocations adding new comments to the existing room?  It could find the comment with the link to the room (which might or might not be the earliest comment on the post), and then send everything after that comment to the existing room.  (It wouldn't need to generate a new auto-comment, but it would need to make sure those users can chat in that room, same as the current behavior.)  One might ask why we shouldn't instead just shut down comments after a move to chat -- once there's a chat room, force everything there and take away the "add comment" link.  Attractive as that idea is to me, it also prevents the (few) comments that are actually what comments are for -- requests for clarification.  If we can come up with a practical way to add some friction for post-migration comments that'd be cool, but we're always going to end up with some comments that should be in the chat room but aren't.  I'd like to have a way to send them there.


Im trying to solve the following question         In the second step  where do they get $k!=2^k-1?$

These are just the examples from my textbook, but I don't think it did not explain well.  One of the problem was to prove the inequality   $$n<2^n$$  for all integers $n$.  I understand we assume if $P(n)$ is true, $P(k+1)$ is true.  Thus $k+1< 2^{k+1}$  But in the text book, they added one more line that I don't understand:  $$k+1<2^k+1 \le 2^k+2^k=2\cdot2^k=2^{k+1}$$  I understand  $$k+1<2^{k+1}$$  But how do I know $2^k+1$ is larger than $k+1$, and smaller than $2^{k+1}$?  I have one another example just in case,  proving $2^n<n!$ using induction.  $$2^{k+1}=2\cdot 2^k<2\cdot k!<(k+1)k!=(k+1)!$$  I understand we should start with $2^{k+1}<(k+1)!$, but  Where did $2\cdot k!$ come from? Textbook says it came from inductive hypothesis, but I still don't get it.  Please advise.


Can we consider an instance of the principle of restricted comprehension in which the property of the elements of a given set A is that of being a subset of a set B? (i.e. A is P(B))

In ZF, the Power Set Axiom (POW) says that given any set $A$, there exists a set $\mathcal{P}(A)$ such that $$ \forall a(a\in\mathcal{P}(A)\leftrightarrow a\subseteq A)\tag{1} $$     Questions:         On many occasions, I've seen POW stated like this: "For any set $A$ there is a set consisting of all subsets of $A$."      Would a more precise formulation be: "For any set $A$ which is known to exist there exists a set containing all subsets of $A$ which are known to exist."?   An instance of the Axiom Schema of Separation (SEP) essentially gives the existence of a subset of a given set. So, why doesn't POW imply SEP? Is it because POW doesn't give the existence of the individual subsets but only the set containing them all?   Conversely, does SEP and the remaining ZF axioms imply POW?


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

I read with interest about Einstein's Theory of Relativity and his proposition about the speed of light being the universal speed limit.    So, if I were to travel in a spacecraft at (practically) the speed of light, would I freeze and stop moving?  Would the universe around me freeze and stop moving?  Who would the time stop for?


I remember that in Oblivion, the game would punish you for leveling up too early. You needed to make sure to have trained the proper skills before gaining a level, or else the enemy would become increasingly stronger than you.  I understand that Skyrim's system is a bit different and shouldn't have this exact problem. But does it mean I can safely level up as soon as I reach the proper level? Are there any valid reasons for me to wait before leveling up?

I play a warrior dual welding two axes and some heavy armour with a dash of conjuration. I have some skills I want to level like smithing that can be power leveled but I am worried this will cause me to gain too many levels too fast.  The leveling in Skyrim feels fast in general, is it ok to power level up a skill or two or do I risk throwing the game off balance?


There are two layouts installed for Persian on my laptop.      I want to uninstall the standard (FAS) layout. But there's only one layout shown in Region & Language      I've also tried to . So I navigated to HKEY_USERS\.DEFAULT\Keyboard Layout\Preload and deleted the corresponding key but after restarting the system, the key is in the registry     and FAS is shown in keyboard layouts in the lower right corner of the screen.

Update: this is a lengthy post, you can     Note: The quick language list refers to the list in the screenshot below, accessible throught the shortcut Win + Space bar  I have two languages for windows spell check in my system, English (United States) and French (Switzerland), but despite both languages being properly configured with "Swiss French" input keyboard, US Keyboard input keeps appearing on this list:    Here's the settings for English (United States) language, you can see the only input is "Swiss French":    Same for Français (Suisse), the only input is "Swiss French":    In the Control Panel, both are also set as Swiss French:    All my settings are set to use "language list":     Here's a few things that I already tried:   I already managed to remove it by some language configuration gymnastics, by adding and removing languages, it always eventually comes back I have already done this:  There's no mention of US Keyboard in my registry settings either:     Please help, I'm desperate, this is my third computer with Windows 10 and they all do the same thing.


Is it possible to prove that   $\frac{\Gamma(n+1,n+1)}{\Gamma(n+1)}/{\frac{\Gamma(n,n)}{\Gamma(n)}}$   this function is decreasing function for n $\geq$ 1  where $\Gamma(n,n) = \int_n^\infty t^{n-1} \mathrm{e}^{-t} \mathrm{d} t$ is the upper incomplete gamma function.  I tried it differentiating, but it is very tricky to handle.  So, I wish anyone's answer or advice or suggestion to help to access this problem.

My problem is how to prove  $$\frac{1+2}{1}  > \frac{1+3+\frac{3^2}{2!}}{1+2} > \frac{1+4+\frac{4^2}{2!}+\frac{4^3}{3!}}{1+3+\frac{3^2}{2!}}>\cdots $$  i am sure that the sequence is decreasing as limit exp(1).  However, the reason why the sequence is decreasing is not evident.  Thanks if you consider this issue and make me relief.


I am writing an article for publication in English. It is necessary to include references to articles written by Russian authors in Russian language. Do I have to translate their names and titles of their articles to English or I can leave their names and titles of the articles in original language (Russian)?  In the Russian-language articles, I see that foreign authors (their names and titles of the articles) are not translated into Russian and left in the original language (English). However, I have not seen articles in English, where Russian/foreign authors and articles were referenced in the original language (i.e. Russian).    For now, I am following  citation style.

Let's say I want to cite a Russian text in my own paper which is written in English. Should I:   reference it as is, in the original Cyrillic alphabet, although the readers won't be able even to pronounce it? transliterate the authors' names, while keeping the rest as is? transliterate the names and translate the title of the work, journal name, etc. into English?


What are good software-solutions in recovering deleted files in Ubuntu on ext3-/ext4- and ntfs-filesystems?  I've been looking for diverse programs, but I couldn't find good ones so far.  TIA

Are there any tools, methods, incantations to recover recently deleted files on Ubuntu?  If it makes any difference, I want to recover a  2.x database file. But would be better to have a method/tool that works on any kind of file.


I have the following table, witch is the relationship pivot table, between posts and tags:    I need to get the posts that strict contain a 'X' given tag(s).  For example:   If I need posts with exclusively tags 1 and 2, it should returns post_id 1 and 4. If I need post with tag 2, it should only returns post_id 3. If I need post with tag 23, it should't returns nothing.   I've tried with:  SELECT * FROM `post_tags` WHERE tag_id = 1 OR tag_id = 2;   but obviously it returns all post_id with these tags_id  And with:  SELECT * FROM `post_tags` WHERE tag_id = 1 AND tag_id = 2;   It doest's return anything, because it's trying to comparate between columns.  Any solution?

This is a very basic query I can't figure out....  Let's say I have a two column table like this:  userid  |  roleid --------|--------    1    |    1    1    |    2    1    |    3    2    |    1   I want to get all distinct userids that have roleids 1, 2 AND 3.  Using the above example, the only result I want returned is userid 1.  How do I do this?


I have a successful jQuery AJAX return and in the success section I create a button.  It all displays correctly in the browser, but clicking on the button has no effect.  I am using the recommended jQuery event delegation of jQuery.fn.on for dynamically created content and it still does not work. Here is the relevant jQuery code containing the event delegation of $("button").on('click', function(): $(document).ready(function() {     $("button").on('click', function() {         alert("One of the buttons was clicked.");     });      const apigw_endpt = "https://blahblah.execute-api.region.amazonaws.com/api";     $.ajax({         url: apigw_endpt + "/return_all_cosmosdb_rcds",         type: "GET",         dataType: "json",         success: function (jsonlist) {             for (var i = 0, size = jsonlist.length; i < size ; i++) {                 $("#table_body").append('
\n');                 let item = jsonlist[i];                 for (const key in item) {                     console.log(`${key}: ${item[key]}`);                     if (key == 'id') {                         $("#table_body").append(`<td>${item[key]}</td>\n`);                         rcd_id = key;                     }                     else if (key == 'image_fname') {                         $("#table_body").append(`<td><button id='button_${i}'>${item[key]}</button></td>\n`);                     } else {                         $("#table_body").append(`<td>${item[key]}</td>\n`);                     }                 }                 $("#table_body").append('
');             }         },         error: function (xhr, status, errorThrown) {             jq_ui_alert('dialog-message', "There was an AJAX problem with the get_all_cosmosdb_rcds Lambda function.");             console.log("Error: " + errorThrown);             console.log("Status: " + status);             console.dir(xhr);         }     }); });  The data returned from the AJAX function looks like this: [     {     "id": "803035021",     "image_fname": "004.JPG",     "_ts": "1612994128"     },     {     "id": "631573429",     "image_fname": "021.JPG",     "_ts": "1612994173"     },     {     "id": "612593039",     "image_fname": "4307733.png",     "_ts": "1612994917"     } ]  Here is the relevant html:

ID	Filename	TimeStamp

I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off.  This happens on page ready and works just fine.  The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound.  I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option.


Planning to apply for UK tourist visa for me and my parents , i have got enough documents but not my parents except passport and identity card.  Is there any chance of visa refusal considering there is not enough documents for my parents, and do i need to apply visa separately or together?  Would be great if someone could answer my queries.

There seems to be a consistent pattern on TSE, with scores of questions about what documentation best accompanies a visa application, posed not just by those reapplying after a refusal, but by first-time applicants prior to submission (and a few with post-submission anxiety).  What is being overlooked, lost in translation, missed? Why is this question even being asked here, when the UK government publishes its own straightforward information?


I've watched a video on background images, and I can only see the background image that I add in the camera view. I can't see it in any other view.  How do I fix this?

How do I put a backdrop behind the model that I am creating so that I can compare the picture to the model while editing?


I am using Visual Studio Code for my Python programming and the problem that I am facing is that on terminal when I type the command python, by default Python 2.7 is loaded. So because of this I am not able to debug my Python 3 commands on my Ubuntu Budgie.  What should I do in order to uninstall Python 2.7 and make 3.7 as my default Python? I have uninstalled Python 2.7 by using the command sudo apt-get remove python. Even after doing this, I have to type python3 to load Python 3.7 and I get an error when just I type python.  How do I make my Python 3 default so that when I type python, Python 3.7 starts?  -Codec Leaper

The python program command executes Python 2. Python 3 can be executed using the python3 command.  How can Python 3 be executed using the python command?


I'm no physicist so it might be a stupid question but is there a maximum energy a single photon can have?  My idea was, that there might be restriction for the minimum wavelength and I thought about the Planck length: $1.616 · 10^{−35}$ m  So my hypothetical photons energy would be:  $$E=hf=\frac{hc}{\lambda}$$  So I put the values inside: $$E=\frac{6.62607015 \cdot 10^{−34}\cdot 299792458}{1.616 \cdot 10^{−35}} \frac{\text {J s m}}{\text{s m}}$$  which gives me the value: $1.23*10^{10}$ J  Is this the maximum amount of energy that a single photon can have, or is the concept of using the planck length as minimal possible wavelength not correct?   And are photons with that much energy even existing in the universe?

Is there any lower or upper limit on the energy of a photon? i.e. does the mathematical framework we currently use to study photons blow up when a photon surpasses a certain upper limit of energy? (or the same on the opposite side?)  My thoughts: If I let the energy of a photon tend to infinity, its wavelength would be tending to zero, and since it is thought that we cannot really distinguish things when they are on the scale of a Planck Length, would the photon have its maximum energy when its wavelength is equal to the Planck length? (Feel free to correct me, I feel I might not be.) and for the opposite end of the spectrum a photon with the least energy would have zero wavelength, implying no photon, which is a trivial case.


I want to merge the values of a multidimensional array that was returned by a function. It contains duplicated values and I want to get rid of the duplicates. I only know that of arrays saved in different variables. This is the array:  Array (     [0] => Array         (             [content] => Array                 (                 [0] => 0                 [2] => 2             )          )      [1] => Array         (             [content] => Array                 (                     [1] => 1                 )          )      [2] => Array         (             [content] => Array                 (                     [0] => 0                     [2] => 2                 )          )  )

How can I remove duplicate values from a multi-dimensional array in PHP?  Example array:  Array (     [0] => Array     (         [0] => abc         [1] => def     )      [1] => Array     (         [0] => ghi         [1] => jkl     )      [2] => Array     (         [0] => mno         [1] => pql     )      [3] => Array     (         [0] => abc         [1] => def     )      [4] => Array     (         [0] => ghi         [1] => jkl     )      [5] => Array     (         [0] => mno         [1] => pql     )  )


I was wondering if walk slow and walk slowly are both correct or if there's a difference between them.    English isn't my first language and I'm sure the rules I learned would only accept slowly as the right word, because it follows a verb.  When I search for walk slow on Google I still get 250,000 results and for walk slowly I get 525,000 results, so walk slow can't be completely wrong.  Which one is right?

Is it acceptable to say "We'll get back to you as quick as we can"? Is "quick" a flat adverb in this case?


I am trying to center a div element on the page, but nothing seems to work. Currently the div grid structure "gallery" is pushed to the left , but I want to center it- does the flex property of its subelements have anything to do with it, and how can I best center it?    .album {   margin: 0;   overflow: hidden; }  .image {   display: inline-block;   margin-bottom: 8px;   margin-right: 8px;   text-decoration: none;   color: black;   cursor: pointer; }  .image:nth-of-type(2n) {   margin-right: 0; }  .image:hover img {   transform: scale(1.15); }  img {   border: none;   max-width: 100%;   height: auto;   display: block;   background: #ccc;   transition: transform .2s ease-in-out; }  .gallery {   margin-top: 1em;   background-color: #86b3d1;   display: flex;   flex-wrap: wrap; }  .main {   background-color: #86b3d1; }

Viewing the Collection for

{{ place_name }}

at {{ address }}

     {% for song, posts in posts_dict.items() %}
       <audio id="{{ song.song_uri[14:] }}" src="{{ song.song_preview }}"></audio>
     {% endfor %}
       <button class="add-button" >Add a song</button>

How can I horizontally center a
 within another
 using CSS?

Foo foo


I was wondering would there be a way for me for do a check if an id exist and if exist do my function then check if next id exist  an example: if log2627251 exist do my function then check or wait for log2627252 exist then do function and keep going    var checkExist = setInterval(function() {    if ($('#log2627251').length) {       console.log("if exists do function then find next id");       clearInterval(checkExist);    } }, 100);
Text

Text

Text

Text
     sorry bad english

How can I check the existence of an element in jQuery?  The current code that I have is this:  if ($(selector).length > 0) {     // Do something }   Is there a more elegant way to approach this? Perhaps a plugin or a function?


I noticed some behavior I found weird while editing a co-workers stored procedure:       create procedure weird_behavior (@switch bit)      as      if (@switch = 0)     begin         select *         into #tables         from sys.tables st         where left(st.name, 1) in ('a','b','c')     end      else if (@switch = 1)     begin         select *          into #tables         from sys.tables st         where left(st.name, 1) in ('d','e','f')     end      select * from #tables      --drop procedure weird_behavior   you get the error:     There is already an object named '#tables' in the database.   This seems odd to me, since only one of the select * into will ever run. I'm forced to rewrite it like so:      create procedure weird_behavior (@switch bit)      as      if (@switch = 0)     begin         select *         into #tables         from sys.tables st         where left(st.name, 1) in ('a','b','c')     end      else if (@switch = 1)     begin         select *          into #tables01         from sys.tables st         where left(st.name, 1) in ('d','e','f')     end      select * from #tables      --drop procedure weird_behavior   This would cause headaches because sometimes the output is in #tables, and sometimes it is in #tables01.  Question: why won't SQL Server let me write this code?

I'm attempting to do this in a procedure:  DECLARE @a bit = 1; BEGIN     SELECT * INTO #aTemp FROM OPENROWSET( ... );      IF @a = 0     BEGIN         SELECT ... INTO #bTemp FROM #aTemp;     END     ELSE     BEGIN         SELECT ... INTO #bTemp FROM #aTemp;     END END   I get the error:  Msg 2714, Level 16, State 1, Line 10 There is already an object named '#bTemp' in the database.   Why is this happening and is there a work around?  Update  I've attempted to add a DROP statement as suggested , but it still does not work:  DECLARE @a bit = 1; BEGIN     SELECT * INTO #aTemp FROM OPENROWSET( ... );      IF @a = 0     BEGIN         IF OBJECT_ID('[tempdb]..#bTemp') IS NOT NULL         BEGIN             DROP TABLE #bTemp;         END          SELECT ... INTO #bTemp FROM #aTemp;     END     ELSE     BEGIN         IF OBJECT_ID('[tempdb]..#bTemp') IS NOT NULL         BEGIN             DROP TABLE #bTemp;         END          SELECT ... INTO #bTemp FROM #aTemp;     END END


I remember watching a Movie years ago but can’t remember the name.   The general premise was that a scientist (I think) finds he is the only man left alive. There are no other signs of any other people anywhere. After a while he meets a female and then another male joins them and I think the female ends up leaving him for the 3rd man.   I think the film was Australian or set in Australia, it was certainly somewhere hot he spends a lot of time studying the sun.   He works out the 3 “survivors” all died at the same moment (think at least 2 of them where suicide)   While he is alone I think there is a scene where he recreates a dictators rally with cardboard cutouts or mannequins   I think it turns out an experiment of his caused whatever happened to happen and I believe he tries to recreate that including killing himself at that moment.   Any idea what the film is?

This was a TV show aired in the UK probably sometime between 1990 and 1993, if memory serves it was only a one-off. The plot starts with the protagonist waking up in bed and being disappointed. He eventually goes outside and everyone is dead, whatever they were doing at the time they died doing it (driving, working, etc.) The protagonist is in a state of panic running around town (I seem to remember it being set in the UK) and he discovers that he's is 'alive' because he'd attempted suicide and died at the exact moment this mysterious event happened. I think he encounters others that 'died' at the time of the event and that's when he realises. I think the protagonist was a bald, white man, probably mid-thirties. Sorry for any vagaries, I was VERY young when it was on. Until recently I assumed it was The Quiet Earth but I've checked and it definitely isn't. It was in colour and was contemporary at the time so it would have been made around 1990.


Yes, I've googled the question but the answers I've found only refer to the old days, before there were getter-only auto-properties.  Today in C# you can declare this:  class Test {   readonly int MyField;   int MyProperty { get; }    public Test()   {     MyField = 42;     MyProperty = 47;   } }   Both declarations can only be initialized either at the line of declaration or in the constructor as seen above.  Is there still a relevant difference between those? Is one to be preferred over the other (e.g. in certain situations, except for interface declaration)?

In C#, what makes a field different from a property, and when should a field be used instead of a property?


Using QGIS 2.16.3, I have uploaded a point dataset. Using the attribute table, I have made a selection of several points, and would like to create a new point layer containing only the selected points. I have consulted:    Problematically, my menu selection is somewhat different form the one here, and I can not choose 'Save selection as'. Is there any other way to choose the selection?

Is it possible to create layers from selection in QGIS?  I am using QGIS 1.7.4-Wroclaw.  To make it easier for others to see this, here are some pics. I used QGIS 2.0.1-Dufour.  SELECT    SAVE    ADD


Okay, so I just started getting good at Blender, and here's what happened: I was just texturing a weird mesh, right. It originally looked like:   But I added textures and everything. I would give y'all the start file, if I knew how. Please help. It mostly had to do with separation in the mesh, UV texturing, material texturing, and idk, but some weird lighting. Please reply and please help me if you can. Thanks.

I was following  on creating a watch and noticed that when I rendered the watch, some pieces were messed up.  I'm new to 3D modeling and I've just learned Blender, I can't explain it well, so here's a picture:    Other examples:     I don't know if it's a problem with my World texture, the object, or the object's texture/material, so I can't even guess how to fix it. What causes this? Is it possible to fix it?


If I have a cell with =hyperlink("http://www.example.com", "Example.com") in it. What formula can I use to extract just the link out of that cell?

Suppose I have a hyperlink in cell A1: =hyperlink("stackexchange.com", "Stack Exchange")  Elsewhere in the sheet, I'd like to have formulas that get the link text and URL from A1, separately. I found a way to get just the link text:   =""&A1    (concatenation with empty string). This returns "Stack Exchange", unlinked.   How to get the URL (stackexchange.com)?


I just installed Ubuntu 16.04 LTS, and because I want to use my Chromecast I think I'll need Chrome or Chromium.  The the software-center ("store") doesn't launch.  So I pasted the line sudo apt-get install chromium in the terminal and entered my password.  chromium-bsu:i386 chromium-bsu   I obtained the following text:  Reading package lists... Done Building dependency tree        Reading state information... Done Package chromium is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source However the following packages replace it:   chromium-bsu:i386 chromium-bsu  Reading package lists... Done Building dependency tree        Reading state information... Done Package chromium is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source However the following packages replace it:   chromium-bsu:i386 chromium-bsu E: Package 'chromium' has no installation candidate   So I pasted chromium-bsu:i386 chromium-bsu  but got this answer:  chromium-bsu:i386: command not found   What now?  I also downloaded the installation file of Chrome,  google-chrome-42-0-2311-90-32-bit-multi-ubu.deb   but nothing happens when I double-click it   I was a Windows user, so I don't know what to do.

I have already tried using the Ubuntu Software Center, but it won't install the Chromium browser. How can I install it using the terminal?


I like to go get coffee while the computer starts. However we have a policy that says the screen must be locked when away.  How can I make sure that the screen locks immediately after logging in?

I want to configure Windows 7 to login automatically after the computer is switched on. That's not because I'm lazy and don't like typing passwords. That's because I want programs that are configured to run on startup run automatically.  But I don't want everyone to see my desktop, so I want my computer to remain locked. When I'm ready to work, I just type my password and don't have to wait until all startup programs run.


The question comes from a textbook  Prove that $3x^5+5x^3+7x$ is divisible by 15 for any integer $x$. I want to do this through mod arithmetic.   The first thing that I did was to try and solve it through mod 3 and 5. If they are congruent to 0 for both, then it is divisible by 15.   So I tried to solve it mod 5 first.  $3x^5+5x^3+7x$ is congruent to $3x^5+x^3+2x$ If x (1 to 5) when subbed in gives 0(mod 5), then all $x$ values will give 0(mod 5).   However when I come to sub in $x=2$, it gives $96+8+4$ which doesn't give 0(mod 5). Have I done or assumed anything wrong up to this point?

I get some troubles with this problem, could you help me? Given prime numbers $p$ and $q$ prove $\exists k\in\mathbb{Z}$ such that $pn^q+qn^p+kn$ is a multiple of $pq,~\forall n\in\mathbb{Z}$.


I want to unwrap a circular shape completely straight for trim textures. But when I do, I got a problem with the texture. It doesn't project right onto the object. I unwraped the model then I took one of the rectangles and turned into a square and finally I hit follow active quads. And this was my final unwrap, Uvs doesnt have stretching. Is there another method for unwrapping or how can I fix this? Thanks. Some screenshots:

Showing the actual 3D model of a curving ramp.  Shows the UVs of that model that blender did automatically. Shows the UV image that I need.   I am going put a road texture on it., but round faces are not helping me at all. All I need is straight belt kind of UV.


Are there any interesting ways of simplifying $(\textbf{a} - \textbf{b})\times(\textbf{a}+\textbf{b})$, where $\textbf{a}$ and $\textbf{b}$ are 3D vectors before I begin to dismantle the expression into a mess like a surgeon?  Thanks in advance.   HMA

Let $\times$ = cross product and $a$ and $b$ have vector signs on them.  $a = [a_1, a_2, a_3]$  $b = [b_1, b_2, b_3]$  How would I prove this? Do I expand out cross product?  Any help is appreciated!


I know, I know; "Is this a scam?", yes, I had to ask.  As of recent, I have heard 3 separate people in conversation on my campus mention a "sales job" they undertook after being contacted on LinkedIn where they "manage accounts" by receiving checks from customers, and then wire the balance of that check to another account minus a 5% take they get to keep.  To me, obviously, this screams "money laundering"; they claim this is the only work they do, that it is legitimate because they are sent tax forms, and that it is legitimate because they have been paid. One of them claimed they've been involved with it for more than two months, and another attempted to smugly defend himself against two academic administrators who told him it was a poor idea.  I've never heard of these scams operating and finding victims through LinkedIn, so that is what makes me 1% skeptic that this is some sort of legitimate business, and I don't know the people I've talked to well enough to even know their name, so I'm unsure what to do about this.  How would I go about reporting this? I've never had any interaction with the scam myself, but I don't like the idea of this spreading to people I know if it is a large networked scam that is either stealing money from students or making them complicit in money laundering.  I don't believe this is a duplicate because apparently these students are given full account details, and it appears to be a large concerted effort to pose as a legitimate business through social media attempting to recruit "salespeople" who redirect transactions over long periods of time. From what I understand, students give their account details, possibly just a routing number, and redirect the transactions and get to keep a cut; the scammers pretend this is a commission, and apparently get them to pay taxes on it (maybe they don't want to go down like Al Capone).

I was on Instagram and saw someone's post about making extra cash.  I inboxed her for details and she said her manager will deposit funds into my account, then I would send them $2000 to split between the both of them.  She stated that I would need to overnight my bankcard to her so her manager can process the deposit.  She didn't ask for anything (neither SSN nor routing or account number) but the bank card only.  I assume that it is a scam.  Can anyone elaborate on this type of scam?  She claim it's not a scam.


In an interview I was asked to sort HashMap by values. Even after I write such a program, it does not print the HashMap in sorted order. Can someone please explain?  public static void main(String[] args) {     // TODO Auto-generated method stub     HashMap<Integer,String> x= new HashMap<Integer,String>();     x.put(3, "arsfd");     x.put(5, "3453");     x.put(6, "sdfsaf");     x.put(8, "wetr");     x.put(11, "cbncvnbv");     List<String> mylist = new ArrayList<String>();     mylist.addAll(x.values());     Collections.sort(mylist);            HashMap<Integer,String> y= new HashMap<Integer,String>();     for(int p=0;p<x.size();p++) {         System.out.println(mylist.get(p));         y.put((Integer) getKey(x,mylist.get(p)), mylist.get(p));     }     System.out.println(y.toString()); } public static Integer getKey(HashMap<Integer,String> x,Object v) {     for(Entry<Integer, String> oo:x.entrySet()) {         if(oo.getValue()==v)             return (Integer)oo.getKey();     }     return null;}

I am relatively new to Java, and often find that I need to sort a Map<Key, Value> on the values.  Since the values are not unique, I find myself converting the keySet into an array, and sorting that array through array sort with a custom comparator that sorts on the value associated with the key.  Is there an easier way?


I want to make a figure in Mathematica, export it as a PDF, edit/label it in Photoshop, and then add it as a figure in a TeX document. I would really like to have the font in the figure closely match the math mode stuff in the document.  In the past I've made a PDF with TeX with just the labels I want and then pasted them all into the figures, but this is incredibly tedious.  I found this post -  - which says that the font in math mode is "Latin Modern Symbol" but this is not an option in Photoshop.  Is there another font that looks close enough to math mode which is in photoshop?  Thanks for any help!

I draw figures in Inkscape. When I label elements within the figures with variable names that I have used in the underlying TeX document, I would like them to look exactly the same as in the document. (e.g. l does not look the same as $l$)  What is the name of the math mode font so I can select it correctly in the Inkscape font list?  If the exact font should not be available, what is a similar looking font that is present on most systems?


I know that the Lorentz factor is  given by: $$\gamma=1/\sqrt{1-v^2/c^2}$$ However $c$ is a function of the medium parameters $\epsilon_0$ and $\mu_0$. Does the Lorentz factor change for the interior of materials or is it always dependent on the speed of light in vacuum. My guess is that it is, because even the interior of a material is mostly vacuum. Have experiments to verify this been done?

We know that the Lorentz transformation is derived using the speed of light in vacuum. But if we were to use it in water, would it change since the speed of light in water should also remain constant for every observer.


During distribution upgrade 14.04 to 15.04, process halts due to many dpkg errors, here are a few of them.  dpkg: too many errors, stopping Errors were encountered while processing:  udev  gnome-bluetooth  systemd  ubuntu-minimal  bluez  indicator-bluetooth  python3-checkbox-support  python3-checkbox-ng  pulseaudio  plainbox-provider-checkbox  mountall  unity-control-center  alsa-base  libcanberra-pulse:amd64  pulseaudio-module-x11  libsolid4  initramfs-tools  udisks2  plainbox-provider-resource-generic  upower  media-player-info  unity-control-center-signon  plymouth  indicator-power  network-manager  ubuntu-drivers-common  kdelibs5-plugins  gnome-user-share  pulseaudio-module-bluetooth  software-properties-gtk  indicator-sound  indicator-network  rhythmbox  ubuntu-desktop  gnome-disk-utility  lightdm  upstart  libconnectivity-qt1:amd64  gnome-session-bin  brltty  linux-image-4.2.0-36-generic  ubuntu-system-settings  dolphin4  unity-greeter  linux-image-generic  checkbox-ng  checkbox-ng-service  libkio5  konqueror  checkbox-gui  gnome-power-manager Processing was halted because there were too many errors.

I am currently using Ubuntu 10.04. I know there is a 10.10 release, but can I upgrade directly to 11.04? Could you walk me through the steps please?


The concept of a partial derivative is very simple: for a multivariate function $f$, the partial derivative of $f$ with respect to a single variable $x$ is computed by treating the other variables as constants and differentiating $f$ with respect to $x$.  As a student of Calculus I, I do not fully understand the need for a $\partial y / \partial x$.  As far as I know, the special “partial” $\partial$ does not change the process of the computation.  In addition, I have become confused as the calculus of my physics course increases in difficulty.  Take a three-dimensional position vector $\vec r = \vec x + \vec y + \vec z$ and an electric field vector $\vec E$ that varies with $\vec r$.  If $V$ denotes electric potential, then $\Delta V = -\int \vec E\cdot d\vec r$.  On a review sheet that my teacher created, he expanded this, saying     $$\begin{align} E_x &= -\partial V / \partial x \\ E_y &= -\partial V / \partial y \\ E_z &= -\partial V / \partial z \end{align}$$   Given the standard setup of a partial derivative, I see no issue with this.  However, our standard formula chart reads that     $$E_x = -\frac{dV}{dx}$$   and this genuinely confuses me since our calculations of field potential are almost always expanded to multiple dimensions.  What is the need for a $\partial f / \partial x$ notation, and why are sources (at least in physics, the only application of partial derivatives I encounter during the course of the school day) inconsistent?

Today, in my lesson, I was introduced to partial derivatives. One of the things that confuses me is the notation. I hope that I am wrong and hope the community can contribute to my learning. In single-variable calculus, we know that, given a function $y =f(x)$, the derivative of $y$ is denoted as $\frac {dy}{dx}$. I understand this as the relative change in $y$, $\delta y$ given a small change in $x$, $\delta x$.  However, in today's lesson on partial derivative, my professor constantly used this notation.   Given a function $z = f(x,y)$, the first derivative with respected to $x$ is written as  $$ \frac{\partial z}{\partial x} $$  So, for example  $$ z = 5x+3y\\ \frac{\partial z}{\partial x} = 5 $$  Why can't I just write it as $$ z = 5x+3y\\ \frac{d z}{d x} = 5 $$  Is it some convention or am I not understanding something in the notation?


I am from India.I intend to travel to the US for a student clinical elective at a university in Texas for the months of November and December. The university will help me obtain an F-1 status. However, I want to attend a few conferences and educational seminars which are being held in January and february for which I will be using a B1/B2 visa which I already have expiring in 2023.  Will I have to leave the US and come back in January using a B1/B2 visa, or is there another way to change my visa status, or should I apply for both visas again.

I am a Canadian citizen, and I intend to travel to the US for a student clinical elective at a university in Texas for the months of September and October. The university will help me obtain an F-1 status. However, I want to attend a few conferences and educational seminars which are being held in November/December for which I will be using a B1/B2 visa.  Will I have to leave the US and come back in November using a B1/B2 visa, or is there another way to change my visa status, or can I apply for both visas upon entering the US?


For no apparent reason, my OS X 10.9.5 Finder has gone haywire. Whenever I create a new Finder window, the main panel, where the files/folders are usually shown, just shows whatever is beneath it, as if there's nothing there. If you drag any other window over the Finder window, that panel will take on the pixels from the other window -- basically the panel is not drawing itself at all.  See screen shot below. It's all greyed out because that's the overlay from the screen shot functionality -- if you look closely you can see how the background is showing through.   I have no idea how or why this happened. I can't think of anything that triggered it. Any idea how to fix this?  Clue 1: rooting the machine doesn't fix it. But  does -- at least immediately. After a few minutes of use after the NVRAM reset, the problem reappears.  Clue 2: Icons and Cover Flow view modes work normally. List and Columns view modes do not -- i.e. they show the behavior noted above.

On our Macbook Air (Mid-2011 11", OS X 10.9.5 Mavericks), starting a few days ago, every time we open Finder windows, the right side just shows screen artifacts/cheese. File Open dialogs in MS Word work fine - it is just the Finder windows with the problem.  Can someone help?  I have tried rebooting, and Verify Disk in Disk Utility. Neither helped. Maybe I should upgrade to El Capitan? But why would this start happening all of a sudden?


After unwrapping a texture in blender cycles in the image editor, is it possible to animate like scale, rotation and etc. of the unwrapped texture? I want to be able to animate the unwrapped area.

This is sort of an unconventional use of Blender, but I'm straightening the distortion of scanned pages of a book, and I have the pages of the book scanned and numbered. What I want to do is use a plane with a simple UV map (two faces, one for the left page and one for the right). I've tested this concept out and it works for a single scanned image. I'm thinking I can run the scanned pages as an animated image sequence. What I'm not sure how to animate is the UV maps. Any idea how I can have a different UV map be called automatically for each frame, corresponding to its number? Maybe there is some way to use Python to update which UV map is used in the material's UV node?


I am using the command texdoc on stata to generate LaTex code. However, whenever I try running the code using pdfLaTex on TexWorks, I get an error saying that the package stata.sty could not be found when I try to use package stata. The code looks something like:  \documentclass{article} \usepackage{stata} \usepackage{graphicx} \begin{document} \section{For Q1} In this section, we cover the following information: \begin{enumerate} \item HH availability and consent, by surveyor \end{enumerate} \end{document}   I have tried changing document class to statapress and using various other packages such as pagedims and sj, based on suggestions on this forum, but it doesn't seem to help. I also tried installing sjextra on stata, but that doesn't work either. Any suggestions would be greatly appreciated!  Thanks, Smriti

I'm trying to manually install the . It's a package to write documents in the Stata Journal style and it's not part of any repository so I cannot install it via the MiKTeX package manager. I have put all the files that come with the package in   C:\Program Files\MiKTeX 2.9\texmf\tex\latex\sjlatex  refreshed FNDB and updated format files. But when I run a simple document that calls up the stata package, I get the error message that stata.sty cannot be found, even though I can see stata.sty in  C:\Program Files\MiKTeX 2.9\texmf\tex\latex\sjlatex  Here's a MWE:  \documentclass{article} \usepackage{stata} \begin{document}  An example:  \begin{stlog} \input{example2_1.log.tex} \end{stlog}  \end{document}   stlog is an environment specified by the stata package, but I don't even get that far before the error message hits. I'm on Windows Vista and running MiKTeX 2.9 in WinEdt.  Also, I checked the file dependencies listed  and, as far as I can tell, I have correctly installed all the required files (using the MiKTeX package manager).  I was hoping someone would have an idea of things I could try? Sorry if there is something obvious that I have missed ...


Did time begin from big bang?  If not then what existed before big bang?  If time had a beginning, then does it have a end, or pause because if time had a pause then we would not have known about it, nor there would be any proof for it so does it happen?

Did spacetime start with the Big Bang?  I mean, was there any presence of this spacetime we are experiencing now before big bang? And could there be a presence/existence of any other space-time before the big bang?


I had applied for a France business Visa in June 2019 with all documents required like invitation letter, cover letter, travel itinerary , my payslips and ITR for 3 years and travel insurance and good amount of savings...but visa was rejected stating "the information submitted regarding the justification for the purpose and conditions of stay was not reliable". Then my employer sent an email in French to the French consulate in Mumbai asking what could be the possible reason for the refusal to which they replied and said to reapply with all documents and to share the email chat between them while reapplying...and still the French consulate rejected stating the same reason when I reapplied in thr month of July...I am unable to figure out what exactly is happening and what should I do in this case.Should I stop applying again or remonstrate or what can be done I am completely clueless.

Schengen refusal formulae can be difficult to understand sometimes.  Sometimes an applicant receives a refusal with:       Justification for the purpose and conditions of the intended stay was not reliable.     often accompanied by:       Your intention to leave the territory of the Member States before the expiry of the visa applied for could not be ascertained.   What is meant by this refusal reason?  What are they trying to say?


I really want to know how to make a singleplayer world turn into a multiplayer world. I need to know the things needed to make it change. I found a YouTube videos about it but it didn't make much sense.

I've been working a lot on my world on my computer in single player mode. My dad got me a server and so I want to transfer my world onto my server.  How is this possible?  I noticed that in %appdata%\roaming\.minecraft\saves, the directories in there look a lot like the world directory on my server. Can I simply transfer my saves directory to my server?


You are missing the following 32-bit libraries, and Steam may not run: libc.so.6 this is the error i keep getting when trying to install steam on ubuntu 14.04

I've already installed Steam, but when I click on the program I get this message  ERROR- You are missing the following 32-bit libraries, and Steam may not run: not   I don't know what to install or even do.


Suppose $G$ is a group and $G = \bigcup_{a \in A} \langle a \rangle B$ for finite sets $A, B \subset G$. Is $G$ virtually cyclic?

This question appears in my textbook's exercises, who can help me prove it?     If a group $G$ is the set-theoretic union of finitely-many cosets, $$G=x_1S_1\cup\cdots\cup x_nS_n$$ prove that at least one of the subgroups $S_i$ has finite index in $G$.   I think that the intersection of these cosets is either empty or a coset of the intersection of all the $S_i$. I want to start from this point to prove it. So I suppose none of these $S_i$ has finite index, but I don't know how to continue?


Three numbers form a geometric sequence. If 5 is added to the second term, then the resulting numbers will constitute an arithmetic sequence. If 22.5 is added to the third number, these numbers will again form a geometric sequence. Find the original numbers.


I would like to prove that $A:=\Bbb{C}[X,Y]/ (X^2-Y^3)$ is not a UFD. This is equivalent to find an irreducible element which is not prime.   I can prove that every element looks like $\overline{P_1X+P_0}$ for $P_1,P_0\in \Bbb{C}[Y]$. After that let $\overline{Y}$ be the "image" of $Y$ in the quotient. It's not prime because the ring $A/(\overline{Y})$ will be isomorphic to $\Bbb{C}[X]\ (X^2)$.      But I am stuck to prove that $Y$ is irreducible,    that is, I write: $$Y=P_1Q_1X^2+P_0Q_1X+P_1Q_0X+P_0Q_0 =P_1Q_1Y^3+P_0Q_0+(P_0Q_1+P_1Q_0)X$$  So by unicity on $\Bbb{C}(Y)[X]$, it's equivalent to  $$Y=P_1Q_1Y^3+P_0Q_0$$ and $$(P_0Q_1+P_1Q_0)X=0.$$  Now taking the value at zero in the first equation, we get that $P_0(0)=0$ (by symmetry). It means that $Y$ divides $P_0$.   Question: How can we continue ?

I'd like to know why $X+(X^2-Y^3)$ and $Y+(X^2-Y^3)$ are irreducible, but not prime in $K[X,Y]/(X^2-Y^3)$.    I failed in both. For the first, I tried to use an isomorphism $$\phi:K[X,Y]/(X^2-Y^3)\to K[X], a_1=0$$ by $X\to X^3, Y\to X^2$ and for the second I tried to construct a case similar to the factorization $3^2=(2+\sqrt-5)(2-\sqrt-5)$.


whenever i try to render this image i get the pixie dust kind of thing near the glass cup, can anyone explain why this is happening?  i have tried changing the roughness of the glass cup but it has no effect i didn't have this problem when i rendered only the plate

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.


Prove by induction the following. $$\frac{1}{2^1} + \frac{2}{2^2} + \frac{3}{2^3} +\dots+\frac{n}{2^n}<2.$$  Caveat: The $<$ will be hard to work with directly. Instead, the equation above can be written in the form,  $$\frac{1}{2^1} + \frac{2}{2^2} + \frac{3}{2^3} +\dots+\frac{n}{2^n}=2-\text{something}.$$  First, find the "something" and then use that form of the equation to prove the assertion.  I can't seem to figure out the form that this equation can be written as. Also, once I find the form how would I do the proof. I understand it involves using a Basic Step and an Induction Step

To prove (1)  $$\sum_{i=1}^n \dfrac {i}{2^i} <2$$  Someone shows that (2)  $$\sum_{i=1}^n \dfrac {i}{2^i} =  2-\dfrac{n+2}{2^n}$$  so we can prove (1).  Can anyone guide me how from (1) they come up with (2) please ? On what base they find (2) ?


Down in the comments of  I mentioned that I'd figure it'd be hard to resurrect someone if you couldn't get access to the Horcrux. @Acccumulation asked whether or not physical posession was required, and although I've always thought it was (seems like all the cases we see in the books do), I didn't know whether or not there was an official answer to this. So, is physical access to the Horcrux actually required, or could you just drop it into the ocean?

If Voldemort's body dies, what process would he use to restore himself from a horcrux? His plans seem sloppy for the pains he had taken. For example, why create horcruxes from pieces of jewellery when they dont have the agency to seek out a new body by themselves?  He needed Quirrel, a person with unlikely ambitions to seek him out to gain an useful body. When that body was gone, he needed Barty Crouch, someone with questionable agency (he could be imprisoned) to transport Harry and draw his blood.  Nagini and the diary seems the only horcruxes with agency, the others are mostly inert.  What plans were ever taken to restore Voldemort from his horcruxes?


This has perpetually confused me. Is our genome made up of two long strands, each strand made up of 23 continuous chromosomes that bind together, or are they 23 free floating separate pair of chromosomes? I think it's the latter because I just learn that genes on different chromosomes assort independently, which would be hard if the genome was a long string, but I'm still not sure.

Do the 46 human chromosomes form a single unbroken DNA helix?  Or is it rather that a human's genome consists of 46 disconnected helices?    If it is the former, does the common numbering scheme for the chromosomes have any correlation to their actual ordering in the one large strand?  If is the latter, is there a convention on how the chromosomes are ordered in genomic datasets?  Also, is there a clear understanding of how sister chromosomes "find" each other in Meiosis I?  Generally, during periods when Mitosis/Meiosis are not occurring,  what's a good physical picture for how the chromosomes are physically arranged (e.g. a bowl of 46 spaghetti noodles, or maybe the sister chromosomes always stay close together, etc)  thanks!


Can I use it to refer to everything. An example:  I took everything out of the washer and put it in the dryer.

Which pronoun should be used with "everything"?  I tend to believe that the following is correct:     I will do everything as soon as it can be done.   but the following also makes sense, considering that "everything" implies "more than 1":     I will do everything as soon as they can be done.


I am trying to install photoshop on ubuntu 16.04. I read the solution, but where do I type commands like sudo apt-get install wine ?

How do you access the command line or run option to put the commands into the system?


I have found the the geocode function in ggmap to be very helpful in the past.  Now I am trying to geocode about 60,000 addresses. The google maps API daily limit is 2500.  Google offers a "pay as you go" service that increases daily limits.      Here is my question:  Is there a way to access a "pay as you go" project through the ggmap geocode function (or something similar)?  If so, how would you do that?  That is:  how to use R's "geocode" for batch geocoding where you are willing to pay to go beyond the daily limit?

I'm looking for a web service providing a full address based on coordinates (and reverse).  I'm ready to pay for that service.  I don't want to use Google's API.


So I recently purchased a MacBook Air. I had initially set it up without an Apple ID, and I saw GarageBand on my machine. I had to reset the MacBook for certain reasons afterwards, so I erased the hard drive and reinstalled macOS High Sierra.  However, when I set up the Mac after it was reset, GarageBand was not there. Is there any way to bring it back? I had not redeemed GarageBand at any point of time.

My hard drive malfunctioned and I had to have it replaced with a new one and reboot my Mac. Now iPhoto, iMovie and garage band have all disappeared and are no longer on my Mac. Is there any way to get them back without having to pay for them?


I wrote a small test to evaluate my programm, but somehow a weired thing happens:     Values of the vector(as printed using 'cout' in the first loop):   0.06   0.06   0.06   0.06   0.06   0.6       Message triggered by the call of function fail         Adjustment at i=4 was 0.06, but should have been 0.06   Somehow this fairly easy comparison of two floats returns false in this loop, but numbers are equal printed and should be equal. Furthermore from i=0 to i=3 comparison of the values evaluate as they should (returning equal)  Somebody know what the problem is?  vector<float> adjustment = *adj.getCalculatedAdjustment(); for (vector<float>::iterator it = adjustment.begin();it!=adjustment.end();it++){     cout << *it << "\n"; } for (unsigned int i=0;i<adjustment.size()-1;i++){     if (adjustment[i]!=(float)0.06){         stringstream ss;         ss << "Adjustment at i=" << i << " was " << adjustment[i] << ", but should have been 0.06";         fail(ss.str());     }  }

What would be the most efficient way to compare two double or two float values?  Simply doing this is not correct:  bool CompareDoubles1 (double A, double B) {    return A == B; }   But something like:  bool CompareDoubles2 (double A, double B)  {    diff = A - B;    return (diff < EPSILON) && (-diff < EPSILON); }   Seems to waste processing.  Does anyone know a smarter float comparer?


I need to write some phonetic transcription in my article, but the compiler can not run it properly. MWE is below,  \begin{tabular}{|c|c|c|c|}     \hline     Words & Phonetics & Students Pronounced & Source \\     \hline      Language &  /’læƞgwIdʒ/ & /leƞgwIdʒ/   & S1,S2,S4,S5,S6\\     Important&  /Im’pᴐ:tnt/ & /Im’pᴐ:tent/ & S1,S2,S3,S5,S8,S9\\     \hline  \end{tabular}   but compiler replace all non-standard character into a question mark (?). This probably because I copy and paste the text. But when I type by using Cyrillic letter symbols from side panel, my code generates errors.   Language - /’l\cyrae \ng{}gwId\cyrabhdze/ - /’l\cyre \ng{}gwId\cyrabhdze/       resulting in   "error undefined control sequenced".     What does it mean?

I wish to write a paper about linguistics, so I thought about trying LaTeX. Sadly I couldn't figure out how to write the unique characters I need for my work, for example epsilon with a little tilde above it, i with two dots above it, velar nasal and so on.  I know I can write stuff like ó with \'{o}, but I couldn't figure out how to put the epsilon in there, or how to write more unique characters.


Maybe I'm searching for the wrong words but I cant find a list of commands needed to do this.  Any help would be really appreciated.  Thank you.

I'm following the , but on launching the upgrade tool I get this response:  Checking for a new ubuntu release No new release found   Am I doing something wrong? Is there a workaround?


I can't play pokemons on 4G, but only on wifi. It worked since yesterday when I couldn't play it anymore. I have htc desire. Please, anyone?

It connects to Pokemon Go via wi-fi perfectly fine, but when I try and connect to Pokemon Go via 3G it just gets stuck at the first bar on the loading screen with the eventual pop up saying "Failed to get player information from the server." My 3G connection works perfectly fine with every other app I have, and has been easily able to stream HD videos so I can't see connectivity with 3G being an issue.   It makes even less sense as once connected via wi-fi, the game easily continues to operate via mobile data once I leave the house. However once the app crashes (which it usually does after 15-30 minutes) I try to reload it on mobile data and it gets stuck on the loading screen. If I can find a local free wi-fi spot nearby I can re-connect easily, and then move back onto mobile data.  I've tried removing and reinstalling Pokemon Go and that didn't work. I also reset all my app preferences on my phone and that didn't work.  Not sure if this helps, my phone is a Huawei P8, Android version 5.0.1.  I signed up to Pokemon Go using my Google account.


Cannot find the 'Manipulate Object Centers Only' button refered to in the book 'Blender Foundations'. Is this an add-on?

I have looked just about everywhere on the Internet and I can't find the answer to this question. Where the hell is the "Manipulate Centers Only" button in Blender 2.8???? It's the the double arrow icon here:    I seem to have enabled it somehow and I can't scale or rotate my object.


I have difficulty of understanding p-value from An Introduction to Statistical Learning by Gareth James • Daniela Witten • Trevor Hastie Robert Tibshirani (2015) : 67  Consider simple linear regression equation $$Y= β_0+ β_1 X$$  Null hypothesis states Y doesn't relate to X, Mathematically $β_1\approx0$ To reject Null hypothesis, we should prove $β_1 >> 0$ After performing linear regression I calculated coefficient to be $\hat{β_{1}}$ .But since number of samples are limited, There is no confidence to reject null hypothesis.   So I calculate t-statistic as $$t_{statistic}=\frac{\hat{β_{1}} - 0}{SE(\hat{β_{1}})}$$ It is trivial to understand that higher t-statistic implies more confidence in $β_{1}$ since $β_{1}$ is larger than error in calculation of itself, hence we can reject Null hypothesis for high t-statistic values    From:  $$t=\frac{\hat{β_{1}} - {β_1}}{SE(\hat{β_{1}})}=\frac{Error\,in\,calculated\,β_{1}}{(Estimated\,Variance)/(\sqrt{n})}$$    Note here that ${β_1}$ & ${SE(\hat{β_{1}})}$ are random variables and vary with batch of samples observed. Let's denote t-distribution as $T(t,n)$ and ${t\,statistic}$ as $T_{st}$   Probability of observing  ${t_{obs}}\ge{t\,statistic}$ is p-value $${p}{-}{value} = \int_{|t|>|T_{st}|}T(t,n)$$ What is mathematical derivation for ${p}{-}{value}\approx 0 \implies β_1 >> 0$ is large ?    I have a quantitative explanation that t-statistic follows t-distribution, if we assume $H_{0}$ is true, and ${p}{-}{value}$ i.e. $\int_{|t|>|T_{st}|}T(t,n)$ denotes probability of getting a value of "t" $\ge T_{st}$ which being less implies hypothesis is false

After taking a statistics course and then trying to help fellow students, I noticed one subject that inspires much head-desk banging is interpreting the results of statistical hypothesis tests.  It seems that students easily learn how to perform the calculations required by a given test but get hung up on interpreting the results.  Many computerized tools report test results in terms of "p values" or "t values".  How would you explain the following points to college students taking their first course in statistics:   What does a "p-value" mean in relation to the hypothesis being tested?  Are there cases when one should be looking for a high p-value or a low p-value? What is the relationship between a p-value and a t-value?


I am in the situation where I may have the opportunity to teach C to some students. The University wants to teach them pure c, not c++, to keep the advanced c++ course separate.  Since c++ is derived from c, is there an official "c rulebook" which contains all the features of c, but none of the c++ features? The reason I want to know is so I can look up what I need to teach the students.  I once saw a (2000 page?) manual on the c++ standard. Does such a thing exist for c, even if it is 20/30 years old by now?  Regards, Ed  EDIT: I should point out I know C/C++ quite well having been teaching myself for 3 years. The only thing I don't know is what things are "officially" C and what things are "officially" C++. This is what I aim to learn so I can give the other students a better education than I could give myself.

For many questions the answer seems to be found in "the standard". However, where do we find that? Preferably online.  Googling can sometimes feel futile, again especially for the C standards, since they are drowned in the flood of discussions on programming forums.  To get this started, since these are the ones I am searching for right now, where are there good online resources for:   C89 C99 C11 C++98 C++03 C++11 C++14 C++17


Using  on TeXworks, I get an error. The code is an output from pandoc converting from markdown to tex.  I checked if I have all the packages with TeX Live Utility. I found the followings.   When I check fontenc I found that I have greek-fontenc package. I am not able find lmodern and fixltx2e For inputenc, I have greek-inputenc I am not able find longtable in TeX Live Utility I have all other packages.   Now my question is how to install packages which I could not find it in TeX Live Utility?  I know  this is a newbie question, but I appreciate your help.  Thanks in advance.   ====  Error  fontenc.sty 100 I can't find file `ecrm1000'. <*> ...ljfour; mag:=1; nonstopmode; input ecrm1000  Please type another input file name ! Emergency stop. <*> ...ljfour; mag:=1; nonstopmode; input ecrm1000  Transcript written on mfput.log. grep: ecrm1000.log: No such file or directory mktextfm: `mf-nowin -progname=mf \mode:=ljfour; mag:=1; nonstopmode; input ecrm1000' failed to make ecrm1000.tfm. kpathsea: Appending font creation commands to missfont.log.  ! Font T1/cmr/m/n/10=ecrm1000 at 10.0pt not loadable: Metric (TFM) file not fou nd. <to be read again>                     relax  l.100 \fontencoding\encodingdefault\selectfont

I freshly installed 'basic' version of TeX Live 2012 (not full, only basic version).  I have following line in my code: \usepackage[T1]{fontenc}  I get following error:  (/usr/local/texlive/2012/texmf-dist/tex/latex/base/fontenc.sty (/usr/local/texlive/2012/texmf-dist/tex/latex/base/t1enc.def) /usr/local/texlive/2012/texmf-dist/tex/latex/base/fontenc.sty:100: Font T1/cmr/ m/n/10=ecrm1000 at 10.0pt not loadable: Metric (TFM) file not found. <to be read again>                     relax  l.100 \fontencoding\encodingdefault\selectfont  /usr/local/texlive/2012/texmf-dist/tex/latex/base/fontenc.sty:100:  ==> Fatal error occurred, no output PDF file produced!   I understand that some packages are missing, however I do not know which ones.  Also, solution to this problem on most of the earlier posts is to install ubuntu latex recommended package, however please note that I am not using LaTeX from Ubuntu's software center (which is old TeX Live 2009) but rather have manually installed basic version of TeX Live 2012 as per instructions here:   Please let me know how do I solve this issue (I don't want to install complete version of TeX Live 2012, only those packages necessary to run this piece of code).


$A$ is a commutative ring with unit and $\mathfrak a$, $\mathfrak b$ ideals. I have to show that $$A/\mathfrak a \otimes_{A} A/\mathfrak b \cong A/(\mathfrak{a+b}).$$ Any hint ?

Martin Brandenburg pointed out  in the comments that he could give a one line proof, using the Yoneda lemma, of $$\frac{\mathbf{C}[x_1,\ldots,x_{n+m}]}{I(X)^e+I(Y)^e} \cong \frac{\mathbf{C}[x_1,\ldots,x_n]}{I(X)} \otimes_\mathbf{C} \frac{\mathbf{C}[x_{n+1},\ldots,x_{n+m}]}{I(Y)}$$ (for $X,Y$ affine algebraic varieties), but apparently the proof was too long for his margin. How can this be done? Fundamental question aside: why is there no abstract nonsense tag?


I had a total of 10 bronze badges when I had only one login using my company ID, but once I added my personal email ID for login, I just got the badges count in Stack Overflow reset to 7; today it got incremented to 8. But surprisingly reputation has not been affected.  It's just getting screwed up. Any idea how to get my badges back?

For the last three days I've been unable to log in to any of the Stack Exchange sites.   I use MyOpenID and I've been having this similar problem:   I made the mistake of adding (so I thought) a Stack Exchange login (my email + password + the same username). However, I think I created a new one that conflicts to the openID user that I managed to get working again.  But, I lost all my badges and tags (most of the badges are returning (with today's date)), and also my flag weight is lost:     NOTE: This only happened on my SO account, all other accounts are ok!  What can I do to return to my old state? I just deleted the SE login and after several logouts am sure I have logged in with openID.  UPDATE: The tags are back. But I'm still missing two silver badges and one gold badge. I assume SO will "return" it as it did with the tags. Also, I also lost all my tag preferences. The flag weight, I can't be sure, I can't find it anywhere.  UPDATE 2: Some days have passed since this happened, and from what I understand, the badges came at the same time (probably the way SO tried to solve this), but I definitely lost my Fanatic gold badge, Enthusiast silver badge and Deputy silver badge (this one denotes the loss of the flag weight).  Is there an email I can write to, or some admin that can sort this, please?  UPDATE 3: The only thing that is missing is the Deputy silver badge (and so my flag weight), I'm now certain that I lost the flag weight and am in the process of "regaining" it by reviewing another 80 posts. It's not the best but I can live with that, because now I don't believe the flag weight + lost badge will return. By the way, each user can view their flag weight in their profile.


I am creating a raster from an LAS Dataset (LAS Dataset represents only the ground return).    I am wondering how do you choose the sampling size? (which I have set to cell size)  My point spacing is 1.886 and my point density is 0.2811.

I am using ArcGIS 10.1 to generate a DEM (bare earth) from LAS dataset. To accomplish this, I use Las Dataset to Raster tool as described in .  I have read here and there in the web that the the cell size of the output raster should be set at a value corresponding to the average LAS points spacing; somewhere else, they suggest to use a value that is three times the average point spacing.  Now, since I wish to produce a bare earth DEM (i.e., with only ground returns), I am wondering if the cell size has to be set at the average point spacing of the whole LAS dataset (i.e., comprising non-ground, ground, etc), or exclusively of the ground points?  On the basis of the ArcGIS's point file information tool (), I managed to get statistics for each LiDAR class. The average spacing (whole dataset) is 1.5 m, while for ground points only is 0.67.  Any insight into the issue?


i recently updated to focal fossa and whenever I run the sudo-apt-update I get this error The repository 'http://ppa.launchpad.net/danielrichter2007/grub-customizer/ubuntu focal Release' does not have a Release file.  how to I remove the ppa in question when I try to purge the ppa I get this error The repository 'http://ppa.launchpad.net/danielrichter2007/grub-customizer/ubuntu focal Release' does not have a Release file.\nWarning:  apt-get update failed for some reason

When updating, I get the following error message:   W: The repository 'http://ppa.launchpad.net/mc3man/trusty-media/ubuntu xenial Release' does not have a Release file.   Here, I find another statement on this error:   This recommends removing certain PPAs; and, I'm not sure if I should do that since it might mean not getting the updates that I need.    Is this what I should do?


There is no student who did not bring his or her ID cards to the examination hall.   There was no student who did not bring his or her ID cards to the examination hall.      I'd like to know the difference in meaning of the two sentences.

I read a sentence in an exam:     There is no child who did not bring his parents to the picnic.    I think that the sentence does not have tense-agreement. Why is is used instead of was? Please explain it to me.


My flight is from BOM to SFO and have 2 layovers first 1 hour 10mins in Amsterdam (Schengen State) and second at London Heathrow (Non Schengen State).    My question is will I need any transit visa for either Amsterdam or London?   I have a valid US visa and my final destination is a US city.   I was able to find questions where both the layovers were Schengen States but not for a Schengen state and a non Schengen State.   P.s. I’m an Indian National

I found many related questions on this site but I am still not sure about the rules. How can I decide if I need a visa to transit? Schengen members as of May 2021 are as follows:  Austria Belgium Czech Republic Denmark (excluding Greenland and the Faroe Islands - but an open border with the Schengen Area is maintained) Estonia Finland France (excluding overseas departments and collectivities) Germany Greece Hungary Iceland Italy Latvia Liechtenstein Lithuania Luxembourg Malta Netherlands (excluding Aruba, Curaçao, Sint Maarten and the Caribbean Netherlands) Norway (excluding Svalbard) Poland Portugal Slovakia Slovenia Spain (except Ceuta and Melilla) Sweden Switzerland


Is there any way I can find all the emails that I sent but have not been replied to by anyone? (One email conversation.)

I'd like to do a search in my Gmail to find out the mails that I sent without reply.   I tried this, but it doesn't work:  label:sent -has:reply   it seems that the 'has' operator only accept :attachment  Is there a way to search the un-replied mails?


Out of universe, some people think that Hufflepuff is "bad", in a condescending sort of way.  Is there anything that parallels this in the books?  Do the other wizards frown down upon Hufflepuffs and think that "getting sorted into Hufflepuff is a pat on the head and a kindly expectation that you'll never accomplish much"?    This question was based on , which seemed somewhat disdainful towards the Hufflepuffs.

I've always struggled to define what makes Hufflepuff a unique house, they seem to share a lot of traits with Gryffindor. I've always considered them to be poorly defined as a house. Going by this  it says this about the houses:  Gryffindor values courage, bravery, loyalty, nerve and chivalry Hufflepuff values hard work, tolerance, loyalty, and fair play  I've highlighted what I believe to be shared traits (Fair-play and Tolerance, to be a subsumed by chivalry) As well as this I can't see any instances of a Hufflepuff working harder than a Gryffindor. What makes Hufflepuff stand out as a house?


Two horizontal circular cylinders both have radius a, and their axes intersect at right angles. Find the volume of their solid of intersection(where a = 1). Is it clear to you that each horizontal cross section of the solid is a square?  I know that this should be found by using integral.But I cannot find the borders and the function that I should integrate( Please do not ask for my way of solving as I could not solve it)

Find the volume common to two circular cylinders, each with radius r, if the axes of the cylinders intersect at right angles. (using disk/washer)  I saw no example of this problem anywhere.. I saw an example how to solve it without calculus but I'm afraid that'll be deductions on my test.. I have the volume of a cylinder and the method of area between two curves but this is out of my reach.... I don't know what I can try...


A physics problem:      A bottle with flies inside it is put on a pan of a balance. When the flies rest on the bottom of the bottle, the beam of the balance is level. If the flies buzz in the middle of the bottle, will the beam of the balance keep motionless?   I've found the standard answer is that the balance will keep motionless. But when a fly lifts off or buzzs about in the middle of the bottle, the force that its fluttering wings apply on the bottom is surely greater than its gravity and produces an acceleration. So the balance will sway.  Perhaps in reality the change is negligible and non-macroscopic.

suppose there is a scale able to measure weight with an uncertainty of $10^{-9}kg$ . On the scale, an airtight plastic chamber is placed. Initially, a fly of mass $10^{-5}kg$ is sitting at the bottom of the chamber, which sits on the scale. At a later point in time the fly is flying around the chamber. Will there be a difference in the observed weight as measured by the scale when the fly is sitting at the bottom of the chamber compared to when it is flying around the chamber at some point in time? If so, what does the value of this difference depend on (I am most concerned with the case where the fly has not touched any surface of the container in enough time for the scale to reach some equilibrium value (or do the pressure variations induced from the flies wings cause constant fluctuations in the scale)?


Would like some help in evaluating the integral $$\int_{1/3}^3 \frac{\tan^{-1}x}{ 1-x+x^2} \, dx$$

Can somebody help me calculate the following integral:  $$\int\limits_{1/3}^{3}\frac{\arctan(x)}{x^2-x+1}\;\mathrm{d}x$$  I have tried integration by parts, but I got stuck in it. Wolfram also didn't help me.  I would be happy to get some hints.


Clearly, $n = 3,6$ are solutions of the following equation. $$ \binom{2n+1}{n+2} = \binom{2n+1}{5} $$  Can we find other values for $n$?


Usually before I load into an OS, I get the option menu to select Windows 7 or Recovery mode(I have thinkpadx220);  Then I used Unetbootin, which appeared as the third option. After installing Ubuntu 15.04, I don't see this option anymore it just goes straight into Ubuntu without the option for Win7, Recovery, or even Unetbootin.  I can still view all my files from Ubuntu though like Program Files and Windows folders.  I already tried this   I made my log at    It didn't fix it.

I just installed Ubuntu alongside to Windows 7, and now Windows 7 will not boot.  When the system starts, it shows me entry for Windows 7 in the boot menu, when I click on the Windows 7 option in the boot menu, after few seconds it will show me the boot menu again and Windows will not boot. It shows me no error message. Windows 7 option is available in the boot menu but it just does not boot.  Here are my boot info results   update - 30/01/2012 I tried windows recovery - fix startup issues - that showed no problems but issues were not resolved  Then I tried the widnows recovery console and run following commands  bootrec /fixboot bootrec/ fixmbr bootrec /RebuildBCD   But that does not help, Now neither ubuntu nor windows will boot. When I boot from windows CD it shows me a valid windows installation in c:\ drive.  update After a lot of help I got from #ubuntu channel and trying out different things, ultimately I can now boot both windows and ubuntu, still, the issue is not completely resolved though.  Here's what made it work  Boot using ubuntu live CD and then run the testdisk utility as steps mentioned  Restart system and I was able to see the boot menu and boot into Ubuntu, then put the following code in boot/grub/custom.cfg. Restart and now I can see one more entry to boot win7, clicking on it boots windows.  menuentry "Windows 7 (loader) with grub ntldr workaround" --class windows --class os   {     insmod part_msdos     insmod ntfs     set root='(hd0,msdos1)'     search --no-floppy --fs-uuid --set=root FAF0F57DF0F54085     ntldr /bootmgr }   It will make windows boot probably but now windows have a dependency on Ubuntu and I can not remove Ubuntu or else windows will stop working.  Credit goes to 'Jordan_U' on #ubuntu channel.   update Here are the win7 boot details I got from EasyBCD  Windows Boot Manager -------------------- identifier              {9dea862c-5cdd-4e70-acc1-f32b344d4795} device                  partition=C: path                    \bootmgr description             Windows Boot Manager locale                  en-US default                 {04fe8f95-4b17-11e1-a45c-909d3d25f938} displayorder            {04fe8f95-4b17-11e1-a45c-909d3d25f938} timeout                 30  Windows Boot Loader ------------------- identifier              {04fe8f95-4b17-11e1-a45c-909d3d25f938} device                  partition=C: path                    \Windows\system32\winload.exe description             Windows 7 Home Premium locale                  en-US osdevice                partition=C: systemroot              \Windows resumeobject            {8d25a443-4b0a-11e1-a835-806e6f6e6963}   Note Still, I am looking for how can I have everything clean and how can I boot windows without having a dependency on Ubuntu. so that if ever I have to remove ubuntu, windows will keep booting file without ubuntu.


Let $X_1, · · · , X_n$ be i.i.d. $\mathrm{Uniform}[\alpha, \beta]$, where $\alpha$ and $\beta$ are unknown.   Show that  $$ E(X_\ast|X(1), X(n)) = \frac{X(1) + X(n)}{2} $$  where $X_\ast$ is the sample mean, and $X(n)$ is the $n$th order statistic.  I know that $X(1),X(n)$ are the sufficient statistics for this family (minimal in fact) and intuitively it makes sense that the expected value of the sample mean will lie in the middle of the max and min. But how do I show it rigorously?

Let $X_{1},\ldots,X_{n}$ be i.i.d. $U[\alpha,\beta]$ r.v.s., and let $X_{(1)}$ denote the $\min$, and $X_{(n)}$ the $\max$. Show that   $$ \mathbb{E}\left(\overline{X}_{n}\mid X_{(1)},X_{(n)}\right) = \frac{X_{(1)}+X_{(n)}}{2}. $$   I know that $\displaystyle\mathbb{E}\left(\overline{X}_{n}\mid X_{(1)},X_{(n)}\right)=\mathbb{E}\left({X}_{1}\mid X_{(1)},X_{(n)}\right)$ but not much more.


These are my favorite tags:    But I still get question like these     Can somebody tell me how I should configure my account so that I get questions related to my "favorite tags"? or is it some kind of bug that I found out :) ?

I want to delve into a new technology, and am not so interested in answering questions in my regular tags any more. So I deleted all my old favourite tags, and created a set of new ones. However, the "interesting" tab, as well as the other question views that I know of, still show mainly stuff from my old tags, and only an occasional question from the new one:  Why is this - could this be Kevin's  at work - which is super cool, but in my case now   Do I really have to actively "ignore" the old tags that I don't want to see? That might conflict with my new area of interest, though, as there may be some overlap between old and new tags and I would want to see them even though they contain an ignored tag.  Edit: ignoring my major old tags (which is not ideal at all) improves the results, but there is still plenty of stuff from esoteric tags that never were even on my "interesting" list - that I probably just happened to view, or be active in, a couple of times:  I can't possibly begin to ignore all the tags that show up here. It appears that my previous question activity is stronger than my expressed preferences - even for stuff I've never heard about, perhaps because of sheer quantity. Can this please be tweaked?


What is the best  Ubuntu version for   vga based laptop. just to get 1280x800 resolution not 3D graphic. any suggestion?

I need to obtain a display adapter for SiS mirage +3 gpu (closed source), so I can run a stable system on Ubuntu.  I need to find a driver for this adapter that is open source and gives completely stable video playback.


I was looking at some different files in /proc, and observed some strange behavior. So, first of all, we know that symlinks [point to names, not files][1]. And when creating a symlink, I can both create a link to a file that doesn't exist, and I can create a link to a file and delete the file, as follows: $ touch foo $ touch bar $ ln -s foo link1 $ ln -s bar link2 $ ln -s doesnotexist link3 $ rm bar $ ls -l  gives lrwxrwxrwx 1 root root  0 Apr 30 15:05 foo lrwxrwxrwx 1 root root  3 Apr 30 15:05 link1 -> foo lrwxrwxrwx 1 root root  3 Apr 30 15:05 link2 -> bar lrwxrwxrwx 1 root root 12 Apr 30 15:05 link2 -> doesnotexist  albeit, with some funny coloring. However, when I go to the /proc interface things (not surprisingly) get weird. Let's say that I create my own program, called myprog. I call it, have it run in the background, and then find the pid. When checking the exe link, it shows my program. $ cd /proc/3762 $ ls -la  Gives the following (sorry, also not surprising) ... lrwxrwxrwx 1 root root  0 Apr 30 15:11 exe -> /home/user/myprog ...  However, what's actually interesting, is that when I move the file, the symlink follows it: $ mv ~/myprog ~/other $ ls -la ... lrwxrwxrwx 1 root root  3 Apr 30 15:05 exe -> /home/user/other ...  What? Why did the symlink follow that file? I tried deleting the file, and in some cases got a .nfsXXX file that I couldn't remove, but in other cases, get a exe -> /dir/to/prog (deleted). Is there a way to force a symlink to track a file, rather than a path? Or, as I presume, is it some built in behavior to the procfs? If so, is that documented somewhere?

If I start a process and then delete the binary of it, I can still recover it from /proc/<pid>/exe:  $ cp `which sleep` . $ ./sleep 10m & [1] 13728 $ rm sleep $ readlink /proc/13728/exe                            /tmp/sleep (deleted) $ cp /proc/13728/exe ./sleep-copy $ diff sleep-copy `which sleep` && echo not different not different $ stat /proc/13728/exe    File: ‘/proc/13728/exe’ -> ‘/tmp/sleep (deleted)’   Size: 0           Blocks: 0          IO Block: 1024   symbolic link   On the other hand, if I make a symbolic link myself, delete the target and attempt to copy:  cp: cannot stat ‘sleep’: No such file or directory   /proc is an interface to the kernel. So does this symbolic link actually point to the copy loaded in memory, but with a more useful name? How does the exe link work, exactly?


What are human rights?   With so many cultures in the world, is it possible to determine what rights should be intrinsic to all humanity?  Is it fair to criticize a separate culture's "human rights" values within their own sovereignty?

What is the basis for believing that there is such a thing as human rights? I am all for human rights but it could be argued that the notion of human rights is imaginary and reducible to absurdity (that humans by virtue of being born are magically entitled to certain things) when trying to prove it scientifically or logically.   It also seems incompatible with evolution, where survival of the fittest would dictate, that you either have what it takes to secure the resources necessary to survive, or you perish if unable to secure said resources. Evolution doesn't state anywhere that everyone is born with a right to a specific allotment of resources. Is it possible to reconcile these contradicting positions or is it more logical to conclude that human rights are a human invention?


I have a pretty nasty problem with events and venues in Drupal. Let say that registered user can add a venue - there is no restrictions. Now I want to make users able to add an event but this one can be assosiated to users own venue not to others. How to limit this access?   I have both events and venues as nodes.   Any ideas?  Cheers Pawel

I have a site where members can sign up and post an article (standard content type) which I'll call STYLE A. I now need to allow the members to create a different article (another content type) which I'll call STYLE B.  One of the fields within STYLE B will be a drop down list of all the article STYLE A's that this specific user has created. The user can then select one of the STYLE A's from the list.  I've tried using the reference and the entity reference modules but I can't quite get it. I've been able to create the reference field so that there is a dropdown of all STYLE A articles but these are not limited to that specific user.  Could anybody help me out. I've tried reading articles on relationships in views etc but it's not quite making sense.  thanks


Question regarding a TV movie from the 80s with a ship crewed entirely by children.  These children were geniuses who were specifically chosen because it was the only way a crew could make it all the way to the destination and back again.  They were shepherding a bunch of scientists, etc., who were in suspended animation.

When I was a kid we had a VHS tape of some Disney live action (not animated) sci-fi movie. It may have been a mini-series or a made-for-tv movie, but I'm not sure. I'm also not sure about the year but it would probably have been late 80s or early 90s based on when I would have seen it. I know it was Disney because they had some live action Goofy and Mickey running around the movie's set as an introduction discussing the plot with a host before the movie.  The plot is basically as follows:   A starship is loaded with mostly children and teenagers as a cross-galaxy human settling effort. Accidents (which are not really accidents and later revealed) cause adult crew members to be killed.  They travel to another planet and face all sorts of troubles. It arrives at the new planet after overcoming obstacles.   Other memorable scenes that may help:   Navigating out of earth's asteroid belt made out of space junk. One of the adults was killed via an airlock malfunction. The ship was supposed to be peaceful with no weapons. At one point they bring on board some crazy guy who puts together a rail gun. There's a memorable line like "Do you want no weapons at all or a well aimed rock?"  There's a planet or space station (I can't remember which) that has a fight scene with the evil bad guy. This scene takes place on what looks to be a carnival or fairground. The bad guys are trying to steal the ship the kids are on because it has some kind of really good futuristic space drive.   Hopefully you remember it better than I do! I've tried looking online for it before with no luck.


I disabled something in the compiz manager, I think I disabled the openGL plugin. Now nothing is showing on my desktop, I can not interact with anything and all I can see is the background wallpaper. The bars are gone, the icons. I've tried resetting the unity, but it did not work. I reinstalled Ubuntu and it also failed. What can I do now? Help me!

When I login, nothing happens.   I am presented with my desktop wallpaper.    No Dash, no Launcher, nothing.


Let $S_{n}(R)$ be a surface area of a $n+1$-dimensional sphere of radius $R$. It is easy to obtain $S_n(R)=S_n(1)R^{n}$. In particular, $S_1(R)=2\pi R$ and $S_2(R)=4\pi R^2$. Consider the sphere $S_n(1)$ centred at the origin with radius 1. A vertical hyperplane $x_1=x$ intersects the sphere and leaves a cuts, which should be a $n$-dimensional sphere $S_{n-1}(r)$. The intuition is that you will obtain a circle when cutting a sphere by a plane. So the nearby surface area of the original $n+1$ sphere can be locally approximated by $\Delta x\cdot S_{n-1}(r)$, the surface area of a slim stripe. Inspired by the calculus approach and summing up the surface areas of all the slim stripes and having $\Delta\rightarrow0$, I have\begin{equation}\label{eq:5}S_n(1)=2\int_0^1S_{n-1}(r)dx,\end{equation} with $r=\sqrt{1-x^2}$. Hence \begin{eqnarray*}S_n(1)&=& 2\int_0^1S_{n-1}(r)dx =2\int_0^1S_{n-1}(1)r^{n-1}dx\\ &=&2 S_{n-1}(1)\int_0^1r^{n-1}dx=2S_{n-1}(1)\int_0^1 (\sqrt{1-x^2})^{n-1}dx.\end{eqnarray*} Let $t=1-x^2$, so $x=\sqrt{1-t}$, and $dx=-1/2\cdot (1-t)^{-1/2}dt$. The last expression becomes \begin{eqnarray*}S_n(1)&=& 2S_{n-1}(1)\int_0^1 (\sqrt{1-x^2})^{n-1}dx=-2S_{n-1}(1)\int_1^0 t^{(n-1)/2}\cdot \frac{1}{2}\cdot (1-t)^{-1/2}dt\\ &=&S_{n-1}(1)\int_0^1 t^{(n-1)/2} (1-t)^{-1/2}dt=S_{n-1}(1)\mathrm{B}(\frac{n+1}{2},\frac{1}{2}),\end{eqnarray*}where the notation $\mathrm{B}$ stands for the Beta function. I therefore obtain a recursive relationship \begin{equation}\label{eq:4}S_{n}(1)=S_{n-1}(1)\frac{\Gamma(\frac{n+1}{2})\Gamma(\frac{1}{2})}{\Gamma(\frac{n+2}{2})}.\end{equation} Utilizing \eqref{eq:4} I conclude that \begin{eqnarray*}S_n(1)&=&S_1(1) \frac{\Gamma(\frac{3}{2})\left[\Gamma(\frac{1}{2})\right]^{n-1}}{\Gamma(\frac{n+2}{2})}=S_1(1) \frac{\frac{\sqrt{\pi}}{2}(\sqrt{\pi})^{n-1}}{\Gamma(\frac{n+2}{2})}\\ &=&2\pi \frac{\frac{1}{2}\pi^{n/2}}{\Gamma(\frac{n+2}{2})}=\frac{\pi^{\frac{n+2}{2}}}{\Gamma(\frac{n+2}{2})}.\end{eqnarray*}  However, when substituting $n=1,2$ into he last expression, I get \begin{eqnarray*}S_1(1)&=&\frac{\pi^{3/2}}{\Gamma(3/2)}=2\pi,\\S_2(1)&=&\frac{\pi^2}{\Gamma(2)}=\pi^2,\end{eqnarray*}where the second equation  is plainly wrong. I trust my calculation is correct. The only possible explanation is therefore my approach to establish the recursive relationship (the first equation) must be wrong. But I don't see where the problem is. Any suggestions or comments are highly appreciated.

I am using two books for my calculus refresher.   Thomas' Calculus  Higher Math for Beginners by Ya. B. Zeldovich   My question is : When applying Integral Calculus for calculation of volumes of solids, generated by curves revolved around an axis, we use slices of 'cylinders' to approximate the volume of the resulting solid and then integrate the sum of those infinitesimal cylinders. However, when we are using the same techniques to calculate the surface area of the surfaces generated by revolving curves around an axis, we consider the 'slope' of the differential length of curve 'dx', calculate the total length of the curve and derive the required surface area.  Are we not supposed to use the same 'slope' for calculating the volumes of the infinitesimal 'cylinders' for calculation of volumes? Shouldn't we use 'sliced portions of 'cones' as the infinitesimal volumes?? When it come to calculation of volumes of solids of revolution, why are we neglecting the slope of the curve for the differential length and simply assume that it is an infinitesimal cylinder??  Ex: Let us say we want to calculate the surface area and the volume of the solid generated when the parabola y = 10 . x^2 is revolved about the y-axis, with limits of x from 0 to 5.  In such cases, when calculating the volume of the solid, we consider infinitesimal 'cylinders', ignoring the 'slope' of the curve for the differential element 'dx', but when calculating the surface area, we consider the 'slope' of the differential element 'dx'.


A $60\times 60$ square $S$ is divided into $2\times 5$ rectangles. Prove that no matter how this is done there is a way to divide $S$ into $1\times 3$ rectangles so that each of the above $2\times 5$  rectangles contains one of the $1\times 3$ rectangles. A bashy idea (which I cannot actually complete) is to show that we can always remove one-by-one connected figures of $30$ squares, composed of three $2\times 5$ rectangles, so that the resulting figure remains connected; and then check that each such figure of $30$ squares can be tiled with a $1\times 3$ rectangles. Any idea of something smarter? (Or if not, at least a fast way to complete the details of the above strategy?) Any help appreciated!

A $60\times 60$ board is partitioned into rectangles of size $2\times 5$ (or $5\times 2$). Is it true that there always exist another partition into rectangles of size $1\times 3$ (or $3\times 1$) such that any $2\times 5$ (or $5\times 2$) rectangle contains a $1\times 3$ (or $3\times 1)$ rectangle?  For the "simple" partition into $2\times 5$ rectangles, this is certainly true: use the simple partition into $1\times 3$ rectangle.  Another way to partition is to first partition the $60\times 60$ board into $12\times 10$ boards, and then for each such board, put two $2\times 5$ at the top and ten $5\times 2$ below. It is not hard to tile each such $12\times 10$ board with $1\times 3$ (or $3\times 1)$ rectangles so that each $2\times 5$ (or $5\times 2$) contains a $1\times 3$ (or $3\times 1)$ rectangle.  (I'm assuming that an $m\times n$ rectangle has $m$ rows and $n$ columns.)


I have a parent directory composed of a set of sub-directories. Each sub-directory is composed of a list of files.  Here is the scenario:  v_1: filenames.txt  v_2: labels.txt  v_3: coding.txt   What is my expected output?  v_1: v_1_filenames.txt  v_2: v_2_labels.txt  v_3: v_3_coding.txt   What l have tried to solve that?   rename -n 's/(.*)\//$1\/$1_/' */*   which prints  rename(v_1/filenames.txt, v_1/v_1_filenames.txt) rename(v_2/labels.txt, v_2/v_2_labels.txt) rename(v_3/coding.txt, v_3/v_3_coding.txt)   However it doesn't work. To confirm that I did:  ls *   and I get:   v_1: filenames.txt  v_2: labels.txt  v_3: coding.txt   Any cue? Thank you

I want to rename file name with its parent folder name, adding the folder name before the current name.  for example:  Folder structure  SOCH NC KT 633-ROYAL BLUE-MULTI | | 1.jpg | | 2.jpg | | 3.jpg   Expected Result  SOCH NC KT 633-ROYAL BLUE-MULTI | |_SOCH NC KT 633-ROYAL BLUE-MULTI1.jpg | |_SOCH NC KT 633-ROYAL BLUE-MULTI2.jpg | |_SOCH NC KT 633-ROYAL BLUE-MULTI3.jpg  SOCH NC KT 710-BLACK-MULTI   Could anyone advise how this can be done in a .sh file? Is there any utility is available to do the operation?


How can I measure the circumference of an ellipse, just by knowing only the width and the height. I would like a nice easy solution. If there is any complex trigonometry, etc., please explain what they do.    Thanks.

Here is a Wikipedia article about the circumference of an ellipse:   I don't know how Ramanujan developed the following approximation for the circumference of an ellipse:  $ \pi\left(3(a+b)-\sqrt{(3a+b)(a+3b)}\right) $  I don't know how to derive this approximation either: $\left(\text{where }h=\frac{(a-b)^2}{(a+b)^2}\right)$  $C\approx\pi\left(a+b\right)\left(1+\frac{3h}{10+\sqrt{4-3h}}\right)$  Can somebody explain how to derive the approximations for an ellipse's circumference? Also, can somebody prove that there is no closed/simple formula for the circumference of an ellipse?


When creating a label you can create a buffer of another color around your text. Is there any way to do so in the print composer?

I would like to add texts with halo, in the composer (not in the map). Do you know a way to do it?  I'm using QGIS 2.0.1