Is it acceptable to write a thank you in a comment?

There have been a number of cases where I would like to thank someone for providing me with a thorough response and give them feedback beyond the vote up. Often I wish people would tell me why they voted me up. Not that the thank you part is necessary but it sets it apart from the other comments related to answering the question itself.  In this type of situation is a "Thank you" acceptable in a comment?     For more information, see  in the .


How to expand 'select' option width after the user wants to select an option

Maybe this is an easy question, maybe not.  I have a select box where I hardcode with width. Say 120px.    <select style="width: 120px">   <option>REALLY LONG TEXT, REALLY LONG TEXT, REALLY LONG TEXT</option>   <option>ABC</option> </select>     I want to be able to show the second option so that the user can see the full length of the text.  Like everything else.  This works fine in Firefox, but doesn't work with Internet Explorer6.


What's in the box at the end of Lovecrafts's Reanimator?

At the end of Herbert West: Reanimator, West has a box delivered to him which he incinerates. The contents of the box are never explicitly mentioned but is it implied as to what's inside?  My guess is that it's       Clapham-Lee's head    but why would he send it to West and why would West incinerate it?


Sending HTML + CSS manipulated by jQuery + Ajax to PHP

I have a form that's calculated on the go. (below picture)   So that table gets created with jQuery & Ajax working with PHP. I want to implement a PDF library that can print that correctly. The tricky part is that I don't know the best way to send that whole table (along with CSS of it in header) to an another PHP file through POST method so that file takes it in and places it inside where it needs to go to PDF get created correctly. What's the best way to go about this?  Process for the table is, first enter dates then select company then click view. At this point, the table gets created, once you click to report it is supposed to create a pdf.  Note to whomever marked this question duplicate: Whoever marked this duplicate, did you really read that other ticket? The other one pure HTML + CSS. I am talking here a page created HTML + CSS and manipulated using AJAX and jQuery! I really don't get people who don't read questions and randomly mark them as duplicate, this has nothing to do with that other question!


I grew up using "preventive" approaches -- Now I see more often "preventative"   Similarly- market "oriented" no longer but "orientated"  When did this change happen? What is correct usage?


On Windows 7, how can I identify any folders that contain files that have not been updated in x years? I would like to clean up unused files/folders on network drives. Initially, I just need a list of "old" folders / directories to be reviewed by others to ok deletion.  Thanks!


How are the higher derivatives (jerk, jounce) of position with respect to time used in physics?

I don't see them much in any physics lesson or course, but that's probably because I'm not into physics as much. I can understand why velocity and acceleration are useful, but why would someone want to care about, let's say the snap, crackle, or pop derivative of position? They also seem rather complicated. Jerk equations.


Is the following proof correct:  Let $X$ be a compact Hausdorff space and $C(X)$ the space of continuous functions $f: X \to \mathbb{C}$. We can equip $C(X)$ with the (edit: sorry, semi-)norm $\lVert f \rVert_\infty = \sup_{x\in X} |f(x)|.$ I want to prove that for $f,g \in C(X)$, $\lVert fg \rVert_\infty \leq \lVert f \rVert_\infty \lVert g \rVert_\infty $. Let $z \in X$ be arbitrary then $$ \lvert f(z)g(z) \rvert \leq \lvert   \; \sup_{x} \lvert f(x) \rvert  g(z)  \;\rvert=\sup_{x} \lvert f(x) \rvert  \lvert    g(z)\rvert \leq \sup_{x} \lvert f(x) \rvert  \sup_{y} \lvert g(y) \rvert.  $$  Since $z$ was arbitrary $$ \sup_{z} f(z)g(z)\leq \sup_{x} f(x) \sup_{y} g(y) $$  that is the sought.


Is there actually a 0 probability of finding an electron in an orbital node?

I have recently read that an orbital node in an atom is a region where there is a 0 chance of finding an electron.  However, I have also read that there is an above 0 chance of finding an electron practically anywhere in space, and such is that orbitals merely represent areas where there is a 95% chance of finding an electron for example.  I would just like to know if there truly is a 0 probability that an electron will be within a region defined by the node.  Many thanks.


I'm a beginner photographer and I want to buy a new camera, can anyone give me some suggestions on what to look for?

I have a Nikon Coolpix L810 (which I know is a very basic camera, but hey, I was just starting out and didn't want anything too complicated.) Now I feel like this camera just isn't doing it for me. I bought some ND lenses, a wide angle lens, and a telephoto lens, but those don't improve the camera. I'm reading more and more about different aspects of photography and what makes a good photo (like changing aperture, ISO, and shutter speed, which I can't do on this camera) and I feel like I won't be able to improve my photography if I don't get a new camera. Therefore, I am looking into buying a better one. So could somebody please give me suggestions? I am going on a trip to Europe around August or September 2016 and I hope to have a new one by then (and it doesn't necessarily have to be nikon). Thanks!


How do I SOSL across objects, matching all records with FIND clause?

To all the expert SOSL gurus lurking out there, I thought this will be an interesting one:  I have some SObjects of different types and I want to return their Name values in a single query.  In advance, I know the IDs and the ObjectTypes of the records whose Names I wish to retrieve. It seems 'wrong' to make several SOQL queries even though there aren't too many types.  So being a good platform citizen, I'm using   to retrieve what I need in a single query:  List<List<SObject>> sobjectsLists = Search.query(     'FIND {*?*} RETURNING ' +     'CustomOne__c (Name WHERE Id IN (\'a01000000000000AAA\')),' +     'CustomTwo__c (Name WHERE Id IN (\'a02000000000000AAB\')),' +     'CustomThr__c (Name WHERE Id IN (\'a03000000000000AAC\'))' ); System.debug(sobjectsLists);   But there is one problem: I must specify at least one FIND character and {*?*} doesn't cut it.     System.SearchException search term must be longer than one character: ?   I've tried this to no avail: {*a* OR *b* OR *c* OR *d* OR *e* OR ...} but even if that did work, it wouldn't help in the case that some twisted cowboy puts underscore (_) or god forbid umlaut (ä).  Any guidance on how I can get the Name of all these records at once?


BACKGROUND: As I was happily watching "Genius" tele-drama's teaser , I came across this very popular and subtle comment:     The past,present and the future all exist simultaneously. Time is nothing but a stubborn illusion.   NOW: After cracking up my mind with time, illusions and time dilation, I concluded myself that Time as in Physics (which is a measurement of what clock reads) is not an illusion. Thanks to this wonderful SE post  (Referring it here since my question is different from this and is not its dupe) but now a part of me fumbles with the other problem, Time Travelling. If time in physics is just a measurement (I don't bother about the other times as time in philosophy-eternalism, the block universe theory, etc.), then why (how) the idea of time travelling exists ? Isn't the term a moot considering that one can travel forward or backward by a few kilometers but with time it's impossible. May be time travelling is associated with relativistic/space time (Einstein's baby). But with the Earth as frame of reference (as we haven't yet colonised the space), time travelling seems to me a scientific fantasy not any better than Christopher Nolan's movie.  Finally my question is "Is the idea of Time Travelling a lie and scientifically unrealistic?"


spamd with postfix: check spam from webmail/localhost

I didn't find any way to set postfix with spamd to check outgoing email from webmail/localhost for attempt to ward off possible spam.


How do I prove that the set of all limit points of a set A is a closed set?

I wanted to prove that the closure of a set is a closed set. The book I use suggested that it would be easier to prove it by first proving that the set (L) of all limit points of a set A is a closed set. Starting the proof I wrote: Let x be a limit point of L such that x it's not in L. This implies that for every epsilon>0, there exist y different from x, such that y lies both in L and in the open interval (x-eps,x+eps). But since y Is in L, for every epsilon>0, there exist z different from y such that z lies in the set A and in the open interval (y-eps,y+eps). I then used the number y lies in (x-eps,x+eps) can be written as |x-y|<eps/2 (since it's true for every eps. it's true for eps/2) and using the same fact i wrote |y-z|<eps/2, adding these two and using the triangular inequality i was able to write that |x-z|<eps Since z is already in A, the only thing left to prove in order for me to prove that x is a limit point of A (and thus produce the contradiction that x is in L), is prove that z is not equal to x, but I'm stuck. Is there a way to prove it? Or maybe is this proof wrong?


I finally got my GPU skinning to work! (Mostly) I'm using MD5 format and this  tutorial  However the weird part is that I'm getting EXACTLY the same issue as this unanswered post:   The animations are opposite. When the head is supposed to be rotation left/right it rotates up/down and the arm when it goes up seems to look like the vertices invert (backface culling proves it since i can see through the mesh and see the inside of the arm)  Any clues the what might be causing this? Questions?


Why don't SO have a feature to get back the offered bounty to a question if the question receives no answers.?

So if i have posted a question and i have awarded some bounty for the question. So if the bounty period expires the bounty points will be reduced from the users account. And the users will never get back the lost points even if the questions does not have an answer. So my question is why SO doesn't have a feature like give back the bounty points to the user if that question receives at least one answer or more than that.  Or what about giving back the bounty points to the user if that question didn't received at least an answer with a minimum number of positive votes..  Otherwise there is no point of losing the points from the reputation.


In python, if I use a ternary operator:  x = a if <condition> else b   Is a executed even if condition is false? Or does condition evaluate first and then goes to either a or b depending on the result?


Where do I add modules to initramfs? (15.04)

I need to add these modules because my usb keyboard is not working when I try to type my encrypted password. usbcore uhci_hcd ehci_hcd usbhid  I guess I need to add these to /etc/initramfs-tools/modules, but where exactly do i add them. Here is the modules file: # List of modules that you want to include in your initramfs. # They will be loaded at boot time in the order below. # # Syntax:  module_name [args ...] # # You must run update-initramfs(8) to effect this change. # # Examples: # # raid1 # sd_mod  Where am I supposed to add it here, and am I doing the right thing (is it safe)?


Why \eqref is not working in sections of beamer?

Why this is not work in beamer?  \documentclass[hyperref]{beamer} \usepackage{hyperref} ... \subsubsection{\protect Verification of \eqref{item:c}} ...


I'm translating a C++ function I wrote some time ago into python when I noticed that my C++ code contains the following lines:    if(MIsScaledOut()) {     if(DataType()==UnknownDataType or DataType()==h)       Descriptor = Descriptor + DataTypeString() + "OverM";   There's an or in there!  This was probably because I previously translated from python, and forgot to switch to ||.  This code compiles in various OSes, with various compilers, and I've never seen a problem with it.  Is this standard, or have I just gotten lucky so far, and this is something I should worry about?


When speaking about studying is it proper to say in simple present like   I study science in the university. or in simple present continuous as I am studying science in the university.


How to get a clean installation copy of mac os High Sierra

I have tried every combination of question and filter stating that I needed a full download of High Sierra. I need to do a clean install on another Mac I have, but every time I get the same download of approx 22MB instead of the ~5GB full install version.  I appreciate any help you can provide.  I never had this issue before they released Mojave, probably just a coincidence.


How do I remove Ubuntu Branding from LiveCD?

I am making a distro based on Ubuntu, I'm using the LiveCDCustomization () and I need to remove any Ubuntu branding, which I believe is just logos and editing the lsb_release file. When looking for how to remove the branding, I cam across a post that's best answer was to go to this page on Ubuntu and follow from there:   The problem is, there's nothing saying how to remove the branding, only that you have to.  EDIT: I'm sorry if this is a duplication. As far as I know, I don't see any posts about this. May you please help me out? I'm planning on releasing it before or on the day of 19.04, thank you :)  EDIT 2: I'm really sorry if I wasted any of y'all's time, but It turns out what I was planning on making is a flavour of Ubuntu.


Show that the sequence $1+\frac{1}{2!}+\frac{1}{3!}+\cdots+\frac{1}{n!}$ is Cauchy. I'm not sure where to start with this problem, I know that if I can show that the sequence is convergent I can manipulate the inequality definition of the limit to have $|X_m-X_n|<\epsilon$ but I don't get how to prove the limit exists.


So I am trying to make a building in Blender for my University Project. I have made the outside of the building and now I am trying to add windows with frames at the front. One side of my building has a window, which I created with no issues. Now I am trying to clone this on the other side of the building I am finding that the loop cut keeps skipping a face of my window for some reason, and I can't figure out why! I have a few screenshots () and hopefully, this shows what I mean. Any help would be appreciated.   Side note, this is my first ever time using Blender so I am not aware of many of the shortcuts etc.  EDIT: Here is my blend file: Removed, can be readded if needed. Don't want my work being flagged up when I upload it.   Thanks


How to avoid having my father's down payment assistance get taxed as a gift

My father has offered to pay up to $70k towards a down payment on a condo for my wife and me. I understand that gifts of over $13k get taxed pretty heavily. Is there a way to avoid this when it comes to him helping with the bulk of the down payment? If he co-signs, does that solve the tax issue?


Could we update the "7 essential meta questions" blog post, or not link it prominently in early beta?

lists some key questions that each site needs to decide -- scope, tagging, etc.  New sites in private beta (and early in public beta) get a link to this post at the top of their meta and it's emailed to beta users, which gives users the impression that these issues should be brought up and decided early.  For some that's true; issues of scope are pretty essential, for instance. But that list also includes "who should the moderators be?" and "what should our site design be?".  The first can lead to early drama (SE chooses the pro-tems, and not until a few weeks in), and the second is very premature (a site doesn't get its design until graduation, which can be a year or two after beta). I'm currently watching a private beta where some users seem to be obsessing over the former and some are expending energy on the latter.  That doesn't seem very productive to me. In addition, as pointed out in comments, some users see this list and think it calls for seven meta posts, one per essential question.  However, some of the essential questions, like FAQ contents and tagging, are really categories of questions, and over-arching questions don't address the need. Could we instead link to something better for early beta, like  (which is now a FAQ entry)?  It seems like the current post + linkage can be a little misleading and distracting at just the wrong time.  The other issues are important, but maybe not on Day 1.


In what situation do we need to implement singleton class in javsacript

In what scenario do we need to implement Singleton Class in javascript as below  var Singleton = (function () {     var instance;      function createInstance() {         var object = new Object("I am the instance");         return object;     }      return {         getInstance: function () {             if (!instance) {                 instance = createInstance();             }             return instance;         }     }; })();  function run() {      var instance1 = Singleton.getInstance();     var instance2 = Singleton.getInstance();      alert("Same instance? " + (instance1 === instance2));   }


How are the degrees of freedom in the emmeans package calculated? - R

Let us look at some sample data for 5 hypothetical subjects.  library(emmeans) library(lme4)  # generate some sample data # condition (Placebo, Treatment) # type (some factor, e.g. two different medications) # value (outcome of interest) # subject  data <- data.frame(condition = as.factor(rep(c(0,1), times = 10)), value = rnorm(20), type = rep(c("A","B"), each = 10), subject = as.factor(rep(rep(1:5, each = 2), times = 2)))   Now we like to conduct a mixed model and post-hoc tests with emmeans, where we test conditions per type in a pairwise fashion:  # caluculate a mixed model fit_data <- lmer(value ~ condition*type + (1|subject), data = data)  # emmeans post-hoc test emmeans(fit_data, pairwise ~ condition | type)   So for each type (A or B), I have paired data (condition 0 has 5 data points and condition 1 has 5 data points). If I would do a paired t-test like so:  # paired t-test t.test(data[data$condition==0 & data$type=="A","value"], data[data$condition==1 & data$type=="A","value"], paired = TRUE) t.test(data[data$condition==0 & data$type=="B","value"], data[data$condition==1 & data$type=="B","value"], paired = TRUE)   I would get degrees of freedom of 4 for the paired t-test, but emmeans says the degrees of freedom are 12. Why is there this huge difference? If the emmeans package also would use df = 4, then the p-values would also be more comparable.


I have  a  requirement where a future method need to be called from batch apex ,I came across various articles stating that a future method could not be called from the batch. Is there any alternate solutions for that?


Creating a bootable usb that runs mainly off of ram, but saves files and applications to the same usb

I am completely new to ubuntu, and I created a live usb with ubuntu 14.10. I booted up to the usb, but it was soo slow compared to using the test version of ubuntu. How can I get my live usb to run nearly as fast as the test version of ubuntu but still be able to install programs to the usb and save files without them getting deleted on restart?  A little bit of further background: I have two usb's. A two gig sd card, and a 32 gig thumb drive. I booted to the (iso) test version of ubuntu on my two gig sd card and formatted the 32 gig thumb drive and installed ubuntu 14.10 to it. I shut down and removed my 2 gig (try ubuntu) sd card. I then booted my computer back up and ran the official copy of ubuntu off of my Usb Thumb drive, but since it was no longer running from ram, it was incredibly slow and lagged so bad. I would like to have this thumb drive as a portable Operating system that I can boot to multiple computers, but I cannot run at this slow rate. Is there a way to load more data to the ram so that it runs faster? Utimately, I would like to be able to run the majority of the OS in ram, but be able to install programs to the usb thumb drive, and save files (like cpp files) to the usb as well.


Trigger is not working in SQL Server 2012 on runtime?

In SQL Server 2012,    I create two tables TABLE1 and TABLE2 After that, I created a trigger for TABLE1 Trigger name: PUSH_TABLE2  SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO  CREATE TRIGGER [dbo].[PUSH_TABLE2]     ON [dbo].[TABLE1]     AFTER INSERT AS BEGIN     DECLARE @col1 VARCHAR(20), @col2 VARCHAR(20), @col3 VARCHAR(20)     SELECT @col1=column1, @col2=column2, @col3=column3 FROM INSERTED      SET NOCOUNT ON;      INSERT INTO [dbo].[TABLE2] VALUES (@col1, @col2, @col3);  END  After creating the trigger PUSH_TABLE2, I test with below insert query manually on TABLE1, triggers works perfectly and its populate the data to both TABLE1 and TABLE2.  INSERT INTO TABLE1 VALUES('session1', 'value1', 'type1');  (1) rows affected.  (1) rows affected.    The problem is if the data is populated through application, it will only populate the data to TABLE1 only, seems trigger is not working. Is it because of my trigger script problem?


What is the meaning of "gate" in this context?

I have found it in an article. Since it may be related to politics, instead of providing with an actual quote of context, let me re-phrase it with my own words:  John Smith, a famous politician, has been caught on a certain kind of public offense. This person has committed similar offenses in the past. The article is titled, "A new Smithgate".  What is the meaning of gate here?


Here is the documents needed.     Here are the documents needed.       Which is grammatically correct and why? My guess would be the second one because of the plural form.


Is it proper to use a colon followed immediately by a hyphen?

I have seen some writing where people have a list or a figure in writing and they will write something like this:     The information is provided in Image   3:-   Is that correct? Is this a British style?


Number of other close votes don't match when for the off-topic detailed list

Just now, when reviewing close votes I voted to close a question and saw that there were four other votes cast for off-topic     but clicked off-topic I could only see one other vote, the other 3 was missing.    I have been seeing this issue many times today.


Can we please see the subject of failed review audits even if the post has been deleted in the meantime?

Yesterday I encountered (and failed) a .   I re-read the post, found that I disagreed with the audit result and clicked I Understand to continue reviewing. I opened the review today, to take a second look but the page just tells me "answer not found".  Whether there was an audit or not - I like to go over my reviews again some time later and see what others made of them (especially in the suggested-edits queue) or if I see them differently by then. For audits based on deleted posts that is not possible.  So here's the feature request: Please show the subject of review audits as it has been displayed when audited, even if the post in question has by now been deleted.  NB: This topic came up now, because yesterday I disagreed with said audit - and would very much like to take a second look at the post again, to see if I still disagree or whether I now (with a good night's sleep in between) agree...


This is an exercise in Artin,     Describe the ring obtained from $\mathbb{Z}$ by adjoining an element $\alpha$ satisfying the two relations $2\alpha - 6 = 0$ and $\alpha - 10 = 0$.    I have seen examples in the text where one relation is imposed on a ring, but not two. I would very much like to see how this is done. Thanks!


Combinatorial Proof of $\sum_{k=0}^m {m \choose k}{n \choose p+k}={m+n \choose m+p}$

I've been working through Richard Hammack's book of proof, where I came across this problem relating to combinatorial proof. show that:$$\sum_{k=0}^m {m \choose k}{n \choose p+k}={m+n \choose m+p}$$ I've managed to reduce the right hand side to $\sum_{k=0}^m{m\choose k}{n\choose m+p-k}$ by creating a set $S$ with $m+n$ elements, and  breaking that into two subsets $A$ and $B$, and counting them separately, then using the Multiplication Principle to combine the results. I presume my problem lays in changing the $m+p-k$ into $p+k$, but any help is appreciated


What is this huge symbol on the door in the Truth realm and in the Neon Genesis Evangelion opening?

In Fullmetal Alchemist the door in the Truth realm has a huge symbol with all kinds of things on it:    I've seen the opening of Neon Genesis Evangelion today and noticed that the same symbol is shown in the beginning of the opening around 0:10 - 0:13.  I first thought that it was just a random symbol in FMA, but now that I've seen it in the opening of NGE, I believe that it must come from something else since there is no connection between those anime.   What is this symbol, where does it come from and what does it describe?  Here is a more detailed picture of the symbol:


I was messing with CompizConfig and now I lost the top panel

I was messing with CompizConfig and I lost the top panel where it tells the time and has the exit buttons and whatnot. Could someone help me get the top panel back? Thank you.


How can I create an alias for a git [action] command (which includes spaces)?

Most of my my aliases are of this form: alias p='pwd'  I want to alias git commit so that it does git commit -v  But trying to create an alias with a space gives an error:  $ alias 'git commit'='git commit -v' -bash: alias: `git commit': invalid alias name


How to reinstall kernels after accidental deletion with a separate boot partition and an encrypted LVM volume?

My installation is a Ubuntu 12.04 64 bits (Classic "legacy" MBR - No  EFI/UEFI here) with two partition :   A separate boot partition An encrypted LUKS volume that contains the system Logical Volumes   I seems I accidentaly deleted all the current kernel files with:  sudo apt-get purge 'linux-image-3.8*'    I applied the updates with Ubuntu Software Update, rebooted and then: Ubuntu can't boot.  I tried to boot on a live DVD with a 14.04.1 Ubuntu and can still see my partitions (described later):  /dev/sda1 (boot) /dev/sda2 (Encrypted volume) /dev/sda5 (Logical Volume container)  What are the steps to recover/reinstall the kernel files and dependencies in order to cleanly reboot my installed system?  Thanks in advance


What Wording Did Witches and Wizards in Other Cultures Use for Spells?

The spells that we know about in the Harry Potter world all seem to be either in Latin, derived from Latin, or resembling Latin.  This makes sense for the European World, but there were likely witches and wizards in Africa, Asia, and the Americas.  These cultures would have developed independently, and the magical people in them would likely have still found ways to cast their spells.  Do cultures with languages that did not derive from Latin use the same words and phrases that are related to Latin for their spells?  Or did they have other phrases based on the languages in their cultures?


Site-wide activity page not being updated

This may or may not be linked with the problem described in  (which is apparently site-wide, not just on Super User).  The site-wide activity page (https://stackexchange.com/users/USER-NUMBER/USER-NAME?tab=activity) which shows a summary of one's activity across all Stack Exchange sites seems not to be being updated.     I'm having trouble uploading an example image (imgur is rejecting the request): you can get to the page by clicking the icon/reputation/badges element in the top menu, then the Network Profile link to the top-right and then selecting the Activity tab.   My page shows my last activity as 22 hours ago, although I have answered at least one question and made a number of comments since then.


Is it possible to interpret regression output omitting the intercept?

Is it possible to interpret regression output when omitting the intercept?  Can this omission be justified?


Can't get onto my brother's server, and vice versa, across local network in Terraria

I have a similar problem to   My problem differs, however, since I have already followed the instructions to set up my MQWest modem for port forwarding. I also do not need Hamachi, since I'm already on the same LAN network as my brother. I've already tried everything suggested, before, but nothing works.   My main question is how do I check if Terraria can access data from the forwarded port, but I also want to know if there is anything else I could try. Any help would be appreciated, thanks!  Random info, in case if any of it can help solve my problem.  Router IP: 192.168.0.1   Port Number: 7777  Modem Brand: MyQwest  Computer: Shuttle desktop, with Windows XP  Btother's Computer: Dell laptop, with Windows 10  We are both using bandwith, connected to the same router.


How long does beef stays good after turning of refrigerator?

During this weekend I accidentally turned of my refrigerator connection before going out and It was like this for about 50 hours without the connection. I had raw beef in there in almost an airtight packet ,when I opened it today , it was still cold , but not frozen. Is it safe to eat this meat ?


Android app crashing when i hit a button

Hey guys so when I hit this particular button it is supposed to take me to the another layout. However everytime i hit it, the entire app crashes. Here is the onCreate method for that page im trying to get to:  protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_bench_data_entry);         //opens the database         openDB();         //Initializes and declares the sensors, and accelerometer         mInitialized = false;         mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);         mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);         mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);       //  tv.setText("Aasfdaf");    }   Here is the onClick for the button I am pressing:   public void onClick_Bench(View v){         //Intent to create a new activity         Intent intent = new Intent(MainMenuActivity.this, BenchDataEntry.class);         //Goes to the Data Entry Screen         startActivity(intent);     }   and here is the error log I am getting when I press the button:  08-08 17:30:30.785  31113-31113/com.example.jacob.repcapture E/AndroidRuntime﹕ FATAL EXCEPTION: main     Process: com.example.jacob.repcapture, PID: 31113     java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.jacob.repcapture/com.example.jacob.repcapture.BenchDataEntry}: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.Window.findViewById(int)' on a null object reference             at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2327)             at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)             at android.app.ActivityThread.-wrap11(ActivityThread.java)             at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)             at android.os.Handler.dispatchMessage(Handler.java:102)             at android.os.Looper.loop(Looper.java:148)             at android.app.ActivityThread.main(ActivityThread.java:5422)             at java.lang.reflect.Method.invoke(Native Method)             at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)             at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)      Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.Window.findViewById(int)' on a null object reference             at android.app.Activity.findViewById(Activity.java:2096)             at com.example.jacob.repcapture.BenchDataEntry.<init>(BenchDataEntry.java:49)             at java.lang.Class.newInstance(Native Method)             at android.app.Instrumentation.newActivity(Instrumentation.java:1067)             at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2317)             at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)             at android.app.ActivityThread.-wrap11(ActivityThread.java)             at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)             at android.os.Handler.dispatchMessage(Handler.java:102)             at android.os.Looper.loop(Looper.java:148)             at android.app.ActivityThread.main(ActivityThread.java:5422)             at java.lang.reflect.Method.invoke(Native Method)             at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)             at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)


How to safely disable Intel Rapid Storage Technology in UEFI BIOS?

I wanted to dual-boot Ubuntu Linux 20.04 with Windows 10, but Linux said that I change mode from RST to AHCI in BIOS. I have one non-RAID disk, also there is an Intel RST controller installed on Windows. How to disable RST without crashing Windows? Thanks


Let: $S_m = \sum_{k=0}^n{((-1)^{n-k}}C_n^kk^m)$. I need to calculate $S_m$ for all $m=0, 1, \ldots, n-1$. As I undertood, it should be equal to zero for all $n, m$ (according to some computations on my PC). But I have no idea how to solve it more formally.


I'm working in Linux.  My connection to PuTTY times out very quickly and I need to have it remain active as long as I wish.  I set the TMOUT in my Linux .profile but that has not seemed to make any difference.    How do I set TMOUT or whatever for PuTTY?


Let $A,B\in M_n(F)$. Set $C(A)=\{X\in M_n(F) \mid XA=AX\}$. Similarly $C(B)$ is defined. If $C(A)\subseteq C(B)$, I have to show $B\in F[A]$. ($F$ is a field.)


Evaluating $\sum^n_{k=0}{n\choose{k}}{m\choose{k}}$ for fixed $m,n$

For evaluating $\sum^n_{k=0}{n\choose{k}}{m\choose{k}}$ for fixed $m,n$, I got ${n+m\choose{n}}$, does it look right?  I rewrite it as $\sum^n_{k=0}{n\choose{n-k}}{m\choose{k}}$, that's what I did.


What is the intuitive meaning of line integral with respect to x?

I know how the line integral is calculated, but I want to know what the meaning of line integral with respect to x is, I mean, intuitively. The integral is $\int_C f(x,y) dx$ or it can be $\int_C f(x,y) dy$. ($C$ is a curve here) Thanks.


What was the weapon that this Stormtrooper used when he fought Finn?

I thought it was odd that a Stormtrooper would be running around a battlefield, dodging blaster fire, with what amounts to a gigantic futuristic sword. When we first see him, I don't think he even has a blaster ( maybe he's dropped it? ), so I assumed the gigantic futuristic sword his only weapon. It raised many questions in my easily confused mind:  What was that weapon called? Why would a Stormtrooper be armed with such a large melee weapon to begin with? Was it specifically designed to duel with a lightsaber? Was that Stormtrooper trained to fight against Jedi ( he really seems to do a better job against Finn than Kylo Ren ) ?  So what was the deal with that weapon?


I have computer A in which I run "xclock" program. I want to forward it's graphical interface to my pc, not directly but through computer B. Is it possible? I'm running xming on my pc.  Resuming: A runs xclock > A forwards to B > B forwards to my PC. Is it possible?


I am trying to automate some functions when a monitor is plugged in or or unplugged.  I am using Ubuntu 15.04.  How can I detect when the monitor changes? Is it possible to execute a shell script when an external monitor is plugged/unplugged in?


If $|ax^2+bx+c|\le1$ for $|x|\le1$(redundant?), then prove that $|cx^2+bx+a|\le2$ for $|x|\le1$.

If $|ax^2+bx+c|\le1$ for $|x|\le1$, then prove that $|cx^2+bx+a|\le2$ for $|x|\le1$. $a,b,c$ are real.  I discovered this to be a duplicate of   With reference to the answer there , is the information $|x|\le1$ redundant as the proof only uses the conditions at $x=1,0,-1$


awk: delete lines where fields 1 and 2 are duplicate

Example of file with duplicate lines:   # more  file.csv   spark2-env,spark_thrift_cmd_opts,--driver-memory 15g --executor-cores 7  spark2-thrift-sparkconf,spark.memory.offHeap.enabled,true  mapred-site,yarn.app.mapreduce.am.command-opts,-Xmx5324m -Dhdp.version=${hdp.version}  spark2-env,spark_thrift_cmd_opts,--driver-memory 15g --executor-cores 7   We created the following awk in order to delete the lines with duplicate strings only in fields 1 and 2, but awk from some unclear reason also deletes  the line where field 3 is duplicate.  What is wrong with my awk syntax?   # awk -F, 'NR==FNR{a[$1,$2]++; next} a[$1,$2]==1'  blueprint_param_file.csv  blueprint_param_file.csv   spark2-thrift-sparkconf,spark.memory.offHeap.enabled,true  mapred-site,yarn.app.mapreduce.am.command-opts,-Xmx5324m -Dhdp.version=\${hdp.version}   Expected output:  spark2-env,spark_thrift_cmd_opts,--driver-memory 15g --executor-cores 7 spark2-thrift-sparkconf,spark.memory.offHeap.enabled,true mapred-site,yarn.app.mapreduce.am.command-opts,-Xmx5324m -


Calculating the probability of gene list overlap between an RNA seq and a ChIP-chip data set

Hopefully someone on these forums can help me out with this basic problem in gene expression studies.  I did deep sequencing of an experimental and a control tissue. I then obtained fold enrichment values of genes in the experimental sample over control. The reference genome has ~15,000 genes. 3,000 out of 15,000 genes are enriched above a certain cut-off in my sample of interest compared to control.  So:  A = total gene population = 15,000 B = RNA-Seq enriched subpopulation = 3,000.  In a previous ChIP-chip experiment, I found 400 genes that are enriched by ChIP-chip. Of the 400 ChIP-chip genes, 100 genes are in the group of 3,000 enriched RNA-Seq transcripts.  So: C= total # of ChIP-chip enriched genes = 400.  What is the probability that my 100 ChIP-chip genes would be enriched by RNA-Seq by chance alone? In other words, what is the most prudent way to calculate if my observed overlap between B and C (100 genes) is any better than that obtained by chance alone? From what I have read so far, the best way to test this is by using hypergeometric distribution.  I used an online calculator (stattrek.com) to set up a hypergeometric distribution test with the following parameters:  - pop size=15,000 - # of successes in population=3,000 - sample size=400,  -# of successes in sample=100.  I get the following for Hypergeometric Probability P(x=100)= 0.00224050636447747  The actual # of genes overlapping between B and C = 100. Is this better than by chance alone? Doesn't look like it is if the chance of any one gene being enriched is 1:5 (3,000 out of 15,000). That's why I don't understand how come my P(x=100) I calculated above is 0.0022. That amounts to a 0.2% chance of the overlap occurring by chance. Shouldn't this be much higher?  If I sampled 400 random genes rom the big list of 15,000, then any 80 of these genes would be expected to be enriched by chance alone (1:5). The number of genes that are actually overlapping is 100, so this is just slightly better than by chance.   I also tried to come up with a solution using the dhyper or phyper functions in R (using what I saw in another post): A=all genes in the genome (15,000) B=RNA-Seq enriched genes  (3,000) C=ChIP-chip enriched genes (400) Here's the R input/output (adapted from a previous stackexchange post):  > totalpop <- 15000     > sample1 <- 3000     > sample2 <- 400     > dhyper(0:2, sample1, totalpop-sample1, sample2)     [1] 4.431784e-40 4.584209e-38 2.364018e-36     > phyper(-1:2, sample1, totalpop-sample1, sample2)     [1] 0.000000e+00 4.431784e-40 4.628526e-38 2.410304e-36       I'm not sure how to interpret these numbers. I believe 2.36e-36 is the probability of getting a complete overlap between B and C by chance alone? But this makes no sense, since that probability is much closer to 1:5. If I start with 15,000 genes, 3,000 will be enriched. Similarly, if I start with 400 ChIP-chip genes, 80 of them should be enriched in the RNA-Seq alone due to the 1:5 chances of enrichment in that data set.  What is the proper way to calculate the p-value, according to the hypergeometric distribution, for the overlap of B and C?


locally finitely presented $\mathcal{O}_X$-modules are quasi-coherent

Let $X$ a scheme. Why do localy finitely presented $\mathcal{O}_X$-modules are quasi-coherent? Does my explaination is correct: one has locally on an open $U$, $$ \mathcal{O}_U^m\to \mathcal{O}_U^n\to\mathcal{F}_{|U}\to 0 $$ so that $\mathcal{F}_{|U}\simeq\mathcal{O}_U^n/\text{Im}(g)$ with $g:\mathcal{O}_U^m\to\mathcal{O}_U^n$, but if $U=\text{Spec}(A)$ one has $\mathcal{O}_U^n=\widetilde{A^n}$ and I guess that the image $\text{Im}(g)=\widetilde{N}$ with $N$ a sub $A$-module of $A^n$ so that $\mathcal{F}_{|U}=\widetilde{A^n/N}$.   In general why locally generated $\mathcal{O}_X$-modules are not quasi-coherent? Here one has locally $f:\mathcal{O}_X^n\to\mathcal{F}_{|U}$ an epimorphism so that $\mathcal{F}_{|U}=\widetilde{A^n}/\text{ker}(f)$. The key point is then: image between quasi-coherent sheaf stay quasi-coherent (here $\text{Im}(g)$) but kernel of (quasi-coherent)$\to$($\mathcal{O}_X$-module) is not always quasi-coherent? Correct?


Manipulating data of dynamic html tags jQuery

I have this code,      $('#gogo').click(function(e){      var data='GoogleMicrosoft";             $("#showResults").html(data);      });       $(".myButtons").click(function(e) {         e.preventDefault();         alert($(this).attr("href"));         $("#result").attr("src", $(this).attr("href"));     });   <button id="gogo">Click me</button>

     I was wondering why it is not working. Perhaps is it because there is no event handler of new added html tags?   I don't want to use a target="result"  Thank you.


Prove the Binomial Expansion with Induction

I'm having trouble with proving the binomial expansion with the principle of mathematical induction. I don't really know where to start, but I think that I managed to prove the first step. The inductive step is proving to be difficult:  Use the principle of mathematical induction to prove the binomial expansion: $$(x+y)^n=\sum_{i=0}^n {n \choose i}x^{n-i}y^i \quad{\forall} \quad n\in \Bbb Z^+$$  Thanks again!!


The screen shows inverted colors, noise in some parts. Can someone please tell me what to do?


I don't know exactly when, but some of my app icons became blank and some keep toggling between normal and blank. It looks like this:  This is my macOS version:  and since I've having a lot of bugs recently, I'm considering reinstall macOS on my MacBook. Is there a easy way to restore the data and applications back after reinstalling the system? I've made a macOS thumb drive with the newest version but I haven't done this on mac before and I don't know how to restore the data. Thanks!    update:  Here's something strange: I backed up my data, erased my entire SSD, and did a clean install of macOS High Sierra. After that I didn't do any restoring actions. I simply copied my documents back, not even copying the apps. And after I run league of legends (or approximately the same time) on my eternal hard drive, my apps begin to turn into blank like that again :(  Before installation I though it must because I'm using the computer for so long and install so many strange things it becomes junky, but after this installation my problem came back again and it's apparently not about anything about the prior system. I think it have several possibilities: 1. my hard drive got infected by some Mac virus (I haven't seen any before but the strange behavior of my computer makes me think that way); 2. somethings wrong with my computer (most likely the SSD) 3. when I run league on my hard drive somehow it triggers an error. I am suspecting the league because every time I try to run it directly it always says the app is damaged and I must open the package and run :league of legend client" within the app package to launch the game. Does anyone have any ideas about this problem? It is really annoying and any help would be greatly appreciated.


Auctex View works or does not depending on how I launched Emacs

I try to open a PDF in Skim from Emacs (via Auctex's View command) on MacOSX Mavericks 10.9.2.  When I open Emacs.app by double-clicking or through Spotlight, it fails. Nothing happens. There's no message and no error. But, when I open Emacs from Terminal (~$ open /Applications/Emacs.app or ~$ /Applications/Emacs.app/Contents/MacOS/Emacs), it works. What's going on here?  In both cases the same Emacs.app is running, the exec-path is the same, and the same command is used: /Applications/Skim.app/Contents/SharedSupport/displayline 25 "test.pdf" "test.tex". These files and test.synctex.gz are in my home directory. So, what's different between launching from Terminal and launching by double-clicking?  This used to work before I upgraded to Mavericks, so I wonder whether this is a Mavericks issue. Has someone been able to open Skim from Emacs on MacOSX Mavericks? Has someone seen something similar?   I tried the latest stable Emacs (24.3) from both Homebrew and  emacsformacosx.com each time with the same result.  Below is some Homebrew information:  ~$ brew doctor Your system is ready to brew. ~$ brew info emacs emacs: stable 24.3, HEAD http://www.gnu.org/software/emacs/ /usr/local/Cellar/emacs/24.3 (3909 files, 115M) *   Built from source with: --cocoa, --srgb From: https://github.com/Homebrew/homebrew/commits/master/Library/Formula/emacs.rb ==> Dependencies Build: pkg-config ✔ Optional: gnutls ✘ ==> Options --cocoa     Build a Cocoa version of emacs --japanese     Patch for Japanese input methods --keep-ctags     Don't remove the ctags executable that emacs provides --srgb     Enable sRGB colors in the Cocoa version of emacs --use-git-head     Use Savannah (faster) git mirror for HEAD builds --with-gnutls     Build with gnutls support --with-x     Include X11 support --HEAD     install HEAD version ==> Caveats .app bundles were installed. Run `brew linkapps` to symlink these to /Applications. ~$


I'm fairly new to unix and I have seen a lot of warnings against using rm -rf.  Example: "But, always double check before you use rm -rf command, if you by mistake give this command in your home directory, or any other important directory, it will not ask to confirm, but it will delete everything there."   Can one still run this command followed by a directory name (rm -rf dirName) without deleting other important things if it is run from a home directory?   Generally, what are the safety rules while working with this command? What should one never type and where?


When I Try To Render My Image It Comes Out Blank

Every time I go to render my image it comes out looking like the image provided. I even tried to copy the model from one scene to another to see if it was my scene that was bugged. I only have one camera in the scene. I'm rendering with Eevee.


What is the Time Complexity of this factorial problem code?

As far as I've learnt, a non-nested loop upto N number of input takes O(N) times,  basic steps like assignment, basic mathematical operations takes O(1) times.   I am confused with the part that, Factorial is a NP problem which takes exponential time complexity(came to know through reading an old thread () but the below code have nothing but N times loop and 2 basic operation. So isn't this code O(N)+O(1) ~~ O(N) ?   Long factorial = 1L ;  for (int c = 1; c<=20; c++){       factorial =(Long) factorial *c ;        }   print(factorial);


I recently discovered that my computer is 64-bit. I have backed up my Home folder, and reinstalled Ubuntu. The reinstall wasn't nearly as painful as I thought. There is one thing that I can't quite seem to figure out: how do I get the 64-bit Firefox Beta build? I always get the Beta builds, but I want to take advantage of the 64-bit architecture of my computer.  says that Mozilla has come out with a 64-bit version of Firefox, but I can't seem to find it.  I do understand  of using a 64-bit browser, but I've decided to jump right in and do it anyway. (Flash and Java are already 64-bit, and who cares about Silverlight, since it's not for Linux anyway?)  There's only one issue, and it's a big one: I can't find the 64-bit Beta PPA!!! (I really hate using .tar.gz files, but I'd be willing to do that as long as I could still access Firefox via the Launcher. Oh, speaking of which, I don't understand .tar.gz files. Once, I managed to run one (the Dropbox Beta build,) but I have no idea whatsoever on how to install them: as in, click on the icon and go.)


Can an algebraic variety be embedded in projective space?

Let $X$ be an algebraic variety over field $k$ . $X$ can be embedded in a complete variety by Nagata's compactification theorem.    Moreover, can we embed $X$ in a projective space $\mathbb{P}_k^n$  $???$ Please give me references which contain either proof or counter examples.


Inline Code Spans should not be used for emphasis, right?

When reviewing Suggested Edits on Stack Overflow, I often come across "fixed formatting" suggestions that use  to place emphasis on certain keywords, but isn't actual code.  For example:     I am having a difficult time with a background task in iOS. The problem I seem to be facing is that iOS is silently terminating the App if my background task runs for too long. What can I do to increase time iOS will wait for my background task to complete?   Gets edited to:     I am having a difficult time with a background task in iOS. The problem I seem to be facing is that iOS is silently terminating the App if my background task runs for too long. What can I do to increase time iOS will wait for my background task to complete?   This seems like an invalid use of an inline code span because, well, it isn't code, and it is distracting. There are a    of these edits being made. Often enough they get approved, which reinforces the behavior.  Is this a valid use of inline code spans? If not, should it be edited and corrected? Should edits suggesting these changes be rejected?


How do I drive 4 motors from a single L293D?

I have 4 DC motors, and I do not need to individually control each of them. Can I connect all the motors parallely to one pair of motor pins on the L293D? Does this pose any issues?  I'm using BO geared motors with the following specs:     RPM - 100;     Output Torque - 0.8--5kgcm;     Operating Voltage - 3v-12v;     No-load Current - 57 mA;


How to make rule trigger on DNS rdata/IP address?

I currently have the following DNS Query Alert rule set up in Suricata (for test purposes):   alert dns any any -> any any (msg:”Test dns_query option”; dns_query; content:”google”; nocase; sid:1;)   Which is triggered when it captures DNS events which contain the word "google", such as in this packet:  {"timestamp":"2017-06-08T15:58:59.907085+0000","flow_id":1798294020028434,"in_iface":"ens33","event_type":"dns","src_ip":"172.16.10.132","src_port":53,"dest_ip":"192.168.160.140","dest_port":52385,"proto":"UDP","dns":{"type":"answer","id":57334,"rcode":"NOERROR","rrname":"www.google.com","rrtype":"A","ttl":300,"rdata":"172.217.12.164"}}   However, instead of searching for resource record names that contain "google", I want to use this same kind of alert to trigger on IP addresses that resolve to loopback, as is the case with the following packet (Notice the rdata field):  {"timestamp":"2017-06-08T15:59:37.120927+0000","flow_id":36683121284050,"in_iface":"ens33","event_type":"dns","src_ip":"172.16.10.132","src_port":53,"dest_ip":"192.168.160.140","dest_port":62260,"proto":"UDP","dns":{"type":"answer","id":53553,"rcode":"NOERROR","rrname":"outlook1.us","rrtype":"A","ttl":120,"rdata":"127.0.0.1"}}   As I have noticed, the contentsection of a Suricata rule searches only for a string. My current rule triggers on a text match with the rrname/domain, how would I make it so that the rule triggers on rdata/IP address?  p.s. Just out of curiosity I tried replacing the "google" in the content section of my alert with "127.0.0.1" and that didn't work either, as expected.


"An operator is hermitian". Implications?

Alastair Rae states that there are 4 postulates of Quantum Mechanics in his text on the subject matter.  The first part of his second postulate can be stated as:      Every dynamical variable may be represented by a Hermitian operator whose eigenvalues represent the result of carrying out a measurement of the value of the dynamical variable...   My question is: just how much can we deduce from saying that the some of the operators involved in Quantum Mechanics are Hermitian?  When I use the word Hermitian, I am referring to the property that $A=A^+$ where $A$ is an operator and $A^+$ is the adjoint of $A$.  Does an operator being Hermitian automatically imply that there will exist eigenfunctions and eigenvalues corresponding to this operator?  Does being Hermitian imply that, should there exist eigenfunctions corresponding to this operator, they will form a complete and orthonormal set?  That any wavefunction can be expanded in terms of these eigenfunction?  Just how much is hidden in the word "Hermitian"?


Im new to software testing, i keep getting java.lang.NullPointerException for some reason and i don't know what it is   This is what i am testing on  public int getNumberOfStudents()     {         int validStudents = 0;         int i = 0;         boolean done = false;          do {             if (students[i] != null && students[i].exists())                 validStudents++;             else                 done = true;             i++;         } while(i < students.length && !done);          return validStudents;     } // end of getNumberOfStudents    This is the test case    class Testing {      RegistrationSystem GNS = new RegistrationSystem();      @Test     //@SpiraTestCase(testCaseId=5487)     public void test() {         assertEquals("validStudents", GNS.getNumberOfStudents());     }     }


Gravity of black hole and that of star that formed it

Since the black hole is formed by a star of  high mass after supernovae it should have less mass than original star. Then how the gravity of black hole is much stronger than a star that formed it? Since F∝Mass of object.


The function $d(n)$ gives the number of positive divisors of $n$, including $n$ itself. For example, $d(25) = 3$ because $25$ has three divisors: $1$, $5$, and $25$. Prove that $d(n)$ is odd if and only if $n$ is a perfect square. I need to prove this by proving that $d(n)$ is odd if and only if $n = k^2$ for some integer $k$.


Reading .zip file header not giving correct output, also struct size does not add up

My main problem is that when reading any .zip file, it isn't reading the data into the struct properly and so the filenameLength property is set to 0 even though it should be correct. I tested with zip.seekg(26) and read that value which gave me the correct value, which makes me think something is wrong with my struct. So I printed out the size of my struct and it gave off 32 even though all the property sizes added up equals 30. What am I doing wrong? struct ZIPHeader {     int sig; // 4     short versionMadeBy; // 6     short extractorversion; // 8     short genflag; // 10     short lastModificationTime; // 12     short lastModificationDate; // 14     int crc; // 18     int compressedSize; // 22     int uncompressedSize; // 26     short filenameLength; // 28     short extraFieldLength; // 30 } zheader;  void PrintZipInfo(const char* dir) {     cout << "Sizeofheader: " << sizeof(ZIPHeader) << endl;     ifstream zip(dir, ios::binary);     zip.read((char *)&zheader, sizeof(ZIPHeader));     cout << "File name length: " << zheader.filenameLength << endl; }  Outputs  Sizeofheader: 32 File name length: 0


If $f \circ g$ is onto then $f$ is onto and if $f \circ g$ is one-to-one then $g$ is one-to-one

I am trying to make a picture in my head so I can understand and remember the rules.  So if $f \circ g$ is onto, it is onto because the function $f$ maps every element from a set $B$ to a set $C$ (thus $f$ is onto) and if $f \circ g$ is one-to-one then every element from set $A$ is mapping an element of set $B$ (and thus is one-to-one).  If both $f$ and $g$ is onto then $f \circ g$ is onto and if both $f$ and $g$ is one-to-one then $f \circ g$ is one-to-one and if both $f$ and $g$ are bijective then $f \circ g$ is bijective?  If $f \circ g$ is bijective, we can't say anything, but that $f$ is onto and that $g$ is one-to-one?  If $f$ is onto and $g$ is one-to-one, nothing can be said?  If $g$ is one-to-one and $g$ is onto, nothing can be said?


Let $X$ denote an open subset of $\mathbb{R}^n$. Suppose $n \in \{0, 1, \dots\}$, $0 < \gamma \le 1$. Does it necessarily follow that $C^{n, \gamma}(\overline{X})$ is a Banach space?


I am completely new to Minecraft. Where can I learn more about how Minecraft's so-called "seeds" work?   (I imagine the Minecraft "world" as a , and the "seed" as an somehow encoded initial configuration from which by certain rules an initial scenery is calculated. But this is most probably not the (whole) truth.)


Problems getting Tikz externalisation to work even on a simple file (LuaTeX)

I am out of my depths to understand what could be going wrong here. I am using luatex (TL 2018) to compile a simple pgfplot example.  This is the error message I get     example_surf.tikz:8: Package tikz Error: Sorry, the system call 'lualatex -shell-escape -halt-on-error -interaction=batchmode -jobname "main-figure0" "\def\tikzexternalrealjob{main}\input{main}"' did NOT result in a usable output file 'main-figure0' (expected one of .pdf:.jpg:.jpeg:.png:). Please verify that you have enabled system calls. For pdflatex, this is 'pdflatex -shell-escape'. Sometimes it is also named 'write 18' or something like that. Or maybe the command simply failed?   This is strange, because in my latexmkrc I have  $pdflatex = 'lualatex %O %S --shell-escape'; $pdf_mode = 1; $postscript_mode = $dvi_mode = 0;   Clearly, we can see that shell-escape is enabled.  Here is a MNWE.  \RequirePackage{luatex85,shellesc}  % not sure if this is required \documentclass[tikz]{standalone} \usepackage{pgfplots} \usepackage{grffile} \pgfplotsset{compat=newest} \usetikzlibrary{plotmarks} \usetikzlibrary{arrows.meta} \usepgfplotslibrary{patchplots} \usepackage{amsmath} \usepgfplotslibrary{external} \tikzset{external/force remake} \tikzexternalize  \begin{document}      \input{example_surf.tikz}  \end{document}   The file example_surf.tikz is a simple 3D surface plot from the pgfplots manual.  \begin{tikzpicture}     \begin{axis}         \addplot3 [         surf,         shader=interp,         ] {x+y};     \end{axis} \end{tikzpicture}   What am I doing wrong?


I have asked this question before, sorry, but I'm still confused about how I can show it. Hope anybody can help me?  We let $f:\mathbb{R}\to\mathbb{R}$ be infinitely often differentiable function and we let the Taylor series be: $$\displaystyle\sum_{n=0}^{\infty}\left(\left(\frac{f^{n}(0)}{n!}\right)x^n\right) $$Let $\{a_n\}_{n\in \mathbb N }$ be $a_n=\frac{f^{n}(0)}{n!}$. We have to assume that the Taylor series converges toward $f$ in an open interval $(-r,r)$ around zero. Then I have to show that if $a_{2n-1}=0$ for all $n\in \mathbb N$ so is $f(-x)=f(x)$ for all $x\in(-r,r)$. How can I do it? I think I maybe can see on $kx^{2n}$ while all odd joints are zero while $a_{2n-1}=0$? But how can I prove it?


Migration of SharePoint from 2007 to 2010/2013

I have a requirement to migrate the sharepoint portal from 2007 to 2010 and 2013.  Please help me with the possible ways in doing it.  Let me know the do's and don't also


What are the differences of "/" and "/home" separately

When i format my dekstop i use "/" and "/Home" as ext4 journaling file system. What are the differences  between "/" and  "/home"


How to resume the interrupted upgrade from 14.10 to 15.04?

Previous the upgrade, my bashrc file was modified in order to add some Path configuration.  While executing do-release-upgrade everything was fine until a message prompted about the status of the bashrc file and an option menu was displayed.   From the menu, I chose the "compare changes" option and the only difference was my previous modification. No problem.   Here is the problem: I ctrl-c and the whole upgrading stopped. After that, I rebooted my computer and from then it is possible to start Ubuntu only in recovery mode.   After logging in (in recovery mode shell) the welcome header message says "Welcome to Ubuntu 15.04" but the "your Ubuntu release is not supported any more" and "new release '15.04' available" warnings still appear.  I've tried to do-release-upgrade again but got the "no new release found" message.  How can I finish or re-run the upgrade??  Thanks


My touchpad action is rotated 90 degrees

I have no idea what happened but when I move my fingers on the touchpad  up and down the mouse pointer scrolls left to right instead and when I scroll left to right it scrolls up and down. How do I fix this?


Show that if a sequence $(x_{n})$ converges weakly for $x \in \ell^{1}$, then the sequence converges strongly. Can anybody help me?


How can I use these references in my bibliography? When I create my bibliography, it change the font of special A' or...., how can I fix it?


Can LaTeX remember from which page the user jumped when clicking on a reference

The answer to this is most likely no. But if someone with deep LaTeX or pdf-viewer knowledge know the answer to be a yes, then please do tell!  Imagine the following situation: a person is reading a thesis on a computer screen. The user clicks on an in-text citation (e.g. [52] ) and jumps to the references page.  It states: [52] M. K. Stenzler and R. R. Eckert. Interactive video. ACM SIGCHI Bulletin, 28(2):76–81, 1996.  This is amazing. There was no scrolling needed, and it would've been a while since this in-text citation was even in the preface! But how does the user go back? The user could scroll or have some menu in which the preface is clickable. But it would be more convenient if the user could go back to where she came from.   My question: is there a way for a user to jump back to where she came from?   One solution would be to generate a "jump back to" line in the reference list when the person is reading the electronic PDF version, but that is non-academic and a bit tedious to read (though an interesting question by itself!).   So I wonder: is it possible for the PDF to somehow remember where the user came from and give a link to jump back?  In our imagined scenario this would happen: the person sees a "jump back" text in the top right corner, clicks on it and jumped back to where she saw her in-text citation.  While that is my question, if there are other clever solutions I will upvote those answers as well, since my goal is to allow the user to go back where he or she came from.  Edit (why this is a non-duplicate): It is pointed out that this question is a lot like:  which is true. It is a lot like that, but I couldn't find it after searching on Google for quite a bit. So there needs to be more general keywords for Google and other search engines to pick it up. Furthermore this question is more broad. This is because I asked three questions: (1) is there a go back button? Or could it be generated? (2) how do you generate go back pages? And (3) are there other clever solutions to solve this problem? It is in essence a usability issue that we're trying to solve in a PDF/LaTeX context, which is for the user to go back easily, the design approach of a solution could be completely different than my first 2 leading questions.  For me personally, the answer is that I will include a pagebackref so that people on paper also are able to go back. And another is to explain in the preface that most PDF readers have a "go back" feature. In the discussion surrounding the answer, I realized using an explicit "go back" link is not needed.


What is $\sum_{k=0}^\infty {k^k \over (k!)^2}$?

I know that this series converges, and the limit is approximately 3.548. But what is the exact sum, and how do you determine it?


Is there a way to refer to a person (using a pronoun) without mentioning a sex?

I just found myself in situation that I am telling about someone who added to me in Skype: because of the nickname I think that it is a girl and used all the time the word «she». But as she didn't say anything yet with exception the "hey :)", I can't even be sure it is a human (it is could be just a bot). So I am afraid that talking about her by using «she» could lead to misunderstanding. Shall I use the word «it»? Or is it wrong? Is there another way?  E.g. in Russian a sex have any noun, so I can say «she» and mean «the person» because the «person» have feminine gender. Either I can say «he», and mean «the one», because it is male gender. So, this way I don't confuse my interlocutor about my knowledge about a person's sex.


Physical meaning of transformation with symmetric matrices

$A$ is a symmetric matrix and $v$ is a vector. I wonder if there is a physical/geometric meaning to the transformation $Av$ due to the symmetry in $A$.


Matrix power series has linearly dependent terms

Prove that for any $(n\times n)$ real matrix, the set of matrices $\{I,M,M^2,...,M^n\}$ are linearly dependent.  More formally, we have to prove that $$\forall M \in \mathbb{R}^{n \times n},\\  \exists (a_0,a_1,\ldots,a_n)\neq (0,0,\ldots,0) \\ \text{such that}\;\; \sum_{i=0}^n a_i M^i =0\,\,.   $$  I have a solution which I will post below, but I would like to see if anyone has a more intuitive or elegant proof.


How do I make browser window always-on-top (or bottom) whenever I open the broswer?

(Actually I want it to be always-on-bottom, but "on-top" is a more common search term).  I know that I can use  wmctrl -r "Mozilla Firefox" -b toggle,below   to set the browser window to be always-below, but how can I set it automatically every time I open the browser?


How do I switch base URL between development and production sites?

The production site is on , while the development site is on . Bringing the production database to the development site breaks all links.  How can I fix this so I can work comfortably and move things between the development and production sites (both running Drupal 8)?


lnk2001 unresolved external symbol with public static variable

"file.h"  template <class ClassType> class NewClass     {     protected:      public:         NewClass() {}         ~NewClass() {}          static long INITIAL_SIZE;     };   "file.cpp"  template<class ClassType> long NewClass<ClassType>::INITIAL_SIZE{ 50 };   "usage file"  in the main function  std::cout << NewClass<char>::INITIAL_SIZE << std::endl;   Can someone please tell me why this gives me a "lnk2001 unresolved external symbol" error?  So whenever I moved:  template<class ClassType> long NewClass<ClassType>::INITIAL_SIZE{ 50 };   to the header file it would throw different error... but once I changed {50} to = 50:  template<class ClassType> long NewClass<ClassType>::INITIAL_SIZE = 50;   it worked. I don't understand why, but the problem was the way I was setting the variable.


My MagSafe to MagSafe 2 converter becomes extremely hot. Why?

Out of nothing, my  became extremely hot while charging. So hot, I could not even touch it.  What could cause it?  I've been using it so I can leave multiple old 85W MagSafe chargers at various places, so I plug my new late 2013 15" Retina MacBook Pro without having to bring a charger.  Edit:  After inspecting for discoloured parts, I saw the flat side of the aluminium surface is a bit discoloured.   This is what I've done after it got hot:   I cleaned everything a couple of times with finger nails and a wooden toothpick (to prevent scratching: electric stuff doesn't like metal fragments). The connector kept getting hot. After turning the connector 180 degrees, it kept cold. If I turned the power plug 180 degrees or 360 degrees, it stays cool too.   Turning 180 degrees was  by  and seems to fix the issue every time this happens.


Preview material texture defferent than render

I'm having problems with making realistic texture. Following Blender Guru tutorial from a year ago I made a plane with custom material using nodes and few images from CrazyBump.   For some reason internal material preview shows my material exactly how I want it, but render is different (both full render [F12] and render preview). There is some data "getting trough" because the plane have a different colour but that's it.   I tried manipulating the nodes, subdividing a plane but nothing seems to work.  Is that just a wrong workflow, or maybe a bug? Am I missing something?  Would appreciate any help. :)  here's a file:


UK visa ban based on an allegedly non-genuine Dutch permit

New Edit/information: I am attaching a picture of the original refusal letter. Personally it makes no sense to me as to why they would think it's a fake permit, especially since she personally went to a police station and got it right then and there. Currently we are trying to find someone in a Dutch embassy or elsewhere to obtain an official letter stating the permit is real. As you can see in the original letter they believe the permit is for a male and of a different nationality... Also, I believe I forgot to mention this but she is Iranian with an Iranian passport.   Side Note: I have blacked out certain parts such as her name, company/employer name, and monthly salary. But just to clarify her salary is equal to over 2,000 British Pounds. Her reason for wanting to travel to the UK was just to travel as she does that a lot and has been to a lot of places. I mean her passports are filled with stamps from all over.  My friend recently applied for a UK visa but she got rejected and banned because they claim there is a non-geniune dutch permit in her old passport. This permit is a piece of paper which she got when she went to Amsterdam in 2011. She went to Amsterdam with a schengen visa and was told she had to check in at a police station, which she did and they put the paper in her passport. She was also told to check in with a dutch embassy outside of the netherlands after she left the country, which she also did and they stamped her passport at the embassy.  The UK visa office rejected her visa once because they claimed the permit is non-geniune, she applied again explaining what the permit is and that it is not how she claims to have entered the netherlands. She also got a letter from the dutch embassy stating she entered the netherlands legally.   They refused the visa again and gave her a 10 year ban based on them claiming it's a non-geniune permit.   I'm curious if anyone else has had a similar issue with the uk visa application and if they have any advice on how to follow up and rectify the issue. I will try and attach copies of the rejection letter and the dutch permit in question.   I should also note that she knows other people who had to do the same process when going to the netherlands. As in she wasn't the only one with that permit in her passport.   Thank you in advance.


Find all functions $f\colon \Bbb R\to \Bbb R$ such that $f(1-f(x)) = x$ for all $x \in \Bbb R$.   This is a question from the national olympiad in Germany 2018.   All i could do is to try with some linear functions like $f(x) = x+1$  I am very good at calculus but I don't know how to approach the problems where I have to find a particular function. Is there a specific algorithm I should use?


why doesn't EM waves get weaker as we travel further away from the source

I know that as we get further away from the charge or from the magnetic field source both magnetic field and electric field decreases ,so why don't electromagnetic waves get weaker as the travel further from the source?


VAR or VECM for a mix of stationary and nonstationary variables

I have 4 time series. One of them is stationary and rest of them are not. I need to find relation between them. I will use AIC to decide lag length.   Should I use VAR or VECM to find relation between them?  Will VAR or VECM give me relation in terms of equation which can be used for forecasting?  Do I need to perform Johansen's test of cointegration?  What good would it do?


I have a question. I work on a console application and I would like Read 3 variable on the same line.  With the language C we can write this  int a; string b; int c;  scanf("%d %s %d", &a, &b, &c);   When I start the program I write : 1+1 on the same line and a = 1 b = "+" c = 1  How can I make the same in C# with console.readline() ?  Thank you in advance,  Nico


What permissions should my website files/folders have on a Linux webserver?

This is a  about File Permissions on a Linux web server.   I have a Linux web server running Apache2 that hosts several websites. Each website has its own folder in /var/www/.  /var/www/contoso.com/ /var/www/contoso.net/ /var/www/fabrikam.com/   The base directory /var/www/ is owned by root:root. Apache is running as www-data:www-data. The Fabrikam website is maintained by two developers, Alice and Bob. Both Contoso websites are maintained by one developer, Eve. All websites allow users to upload images. If a website is compromised, the impact should be as limited as possible.  I want to know the best way to set up permissions so that Apache can serve the content, the website is secure from attacks, and the developers can still make changes. One of the websites is structured like this:  /var/www/fabrikam.com     /cache     /modules     /styles     /uploads     /index.php   How should the permissions be set on these directories and files? I read somewhere that you should never use 777 permissions on a website, but I don't understand what problems that could cause. During busy periods, the website automatically caches some pages and stores the results in the cache folder. All of the content submitted by website visitors is saved to the uploads folder.


Prove that $(X,\Vert {\cdot}\Vert_2)$ is not complete where $\Vert f\Vert_2=\left(\int_{-2}^{2}|f(t)|^2 dt\right)^{1/2}$

Prove that $(X,\Vert {\cdot}\Vert_2)$ is not complete where $X=C[-2,2]$ and \begin{align}\Vert f\Vert_2=\left(\int_{-2}^{2}|f(t)|^2 dt\right)^{1/2}.\end{align}  MY TRIAL  It suffices to produce a Cauchy sequence in $C[-2,2]$ that does not converge to a point in $C[-2,2]$.  Consider the function defined by   \begin{align} f_n(t)=\begin{cases}0,& \text{if}\;-2\leq t\leq 0,\\nt,& \text{if}\;0\leq t\leq \frac{1}{n},\\1 &\text{if}\;\frac{1}{n}\leq t\leq 2.\end{cases} \end{align} Clearly, the above function is continuous by Pasting Lemma. Next, we show that the function is Cauchy.  Let $m,n\in \Bbb{N}$ such that $m\geq n.$ Then, we show that  \begin{align} \Vert f_n-f_m\Vert_2=\left(\int_{-2}^{2}|f_m(t)-f_n(t)|^2 dt\right)^{1/2} \to 0,\; \text{as}\;n\to \infty.\end{align}  Now, \begin{align} \Vert f_n-f_m\Vert_2\leq\left(\int_{-2}^{2}|f_m(t)||f_m(t)-f_n(t)| +|f_n(t)||f_m(t)-f_n(t)|  dt\right)^{1/2} \end{align}  We know that \begin{align} \int_{-2}^{2}|f(t)| dt\leq\sqrt{4}\left(\int_{-2}^{2}|f(t)|^2 dt\right)^{1/2}\end{align}  So,  \begin{align} \Vert f_n-f_m\Vert_2\leq\left(\int_{-2}^{2}|f_m(t)||f_m(t)-f_n(t)|dt +\int_{-2}^{2}|f_n(t)||f_m(t)-f_n(t)|  dt\right)^{1/2} \end{align}  I'm stuck here and don't know how to proceed. Any help please?


Python script has no stdout when started via i3blocks

In i3blocks, I have defined a block like this: ~/.config/i3blocks/config: [test] interval=persist format=json  The corresponding executable script: ~/.config/i3blocks/config.scripts/test: #!/usr/bin/python  from time import sleep  while True:      print("test")      sleep(5)  I intend to replace "test" with an actual JSON-String later, I just stripped it down to this version for debugging purposes. When I execute this on the command line, test gets printed to stdout every 5 seconds, as expected. I can get the PID with ps aux and check strace: $ sudo strace -p82267 -s9999 -e write strace: Process 82267 attached write(1, "test\n", 5)                   = 5 write(1, "test\n", 5)                   = 5 [...]  ps aux also shows me the other process that i3blocks has started. strace with that process gives me no output, and I don't understand why. The loop seems to be running, but there is no stdout. To verify this, I removed the loop and restarted i3blocks, and the process is not listed anymore. Why is there no stdout when i3blocks starts the process, and what can I do about that? Edit: I let it run for a long while and just noticed: strace shows me that a whole bunch of text was dumped to stdout all at once: $ sudo strace -p79878 -s9999 -e write strace: Process 79878 attached --- SIGSTOP {si_signo=SIGSTOP, si_code=SI_USER, si_pid=79873, si_uid=1000} --- --- stopped by SIGSTOP --- --- SIGCONT {si_signo=SIGCONT, si_code=SI_USER, si_pid=79873, si_uid=1000}  write(1, "test\ntest\n[...a big big block of output here...]test\ntest", 8194) = 8194  The SIGSTOP and SIGCONT also happened several times. So it seems like the output is stored in some buffer for very long, and then dumped to stdout all at once at some point. What can I do about that?


What is the difference between "all", "default" and "eth*" in /proc/sys/net/ipv[46]/conf/?

In sysctl, the /proc/sys/net/ipv[46]/conf/ keys have the following subkeys: all, default, and a key for each network interface. For example, on a machine with a single network interface eth0, it will look like this:  iserv ~ # ll /proc/sys/net/ipv[46]/conf/ /proc/sys/net/ipv4/conf/: insgesamt 0 dr-xr-xr-x 0 root root 0 12. Sep 23:30 all/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 default/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 eth0/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 lo/  /proc/sys/net/ipv6/conf/: insgesamt 0 dr-xr-xr-x 0 root root 0 12. Sep 23:30 all/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 default/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 eth0/ dr-xr-xr-x 0 root root 0 12. Sep 23:30 lo/   All the respective settings exist in each key separately. For example, if I want to disable IPv6 Router Advertisements with the accept_ra value, this value exists four times:  iserv ~ # sysctl -a 2>/dev/null | grep "accept_ra " net.ipv6.conf.all.accept_ra = 1 net.ipv6.conf.default.accept_ra = 1 net.ipv6.conf.lo.accept_ra = 1 net.ipv6.conf.eth0.accept_ra = 1   My question now is: which of these values do I need to change? I figured all (to change all existing interfaces) and default (to change all new interfaces that may appear later), but changing these still leaves the value at 1 for lo and eth0:  iserv ~ # sysctl -w net.ipv6.conf.all.accept_ra=0 net.ipv6.conf.all.accept_ra = 0 iserv ~ # sysctl -w net.ipv6.conf.default.accept_ra=0 net.ipv6.conf.default.accept_ra = 0 iserv ~ # sysctl -a 2>/dev/null | grep "accept_ra "   net.ipv6.conf.all.accept_ra = 0 net.ipv6.conf.default.accept_ra = 0 net.ipv6.conf.lo.accept_ra = 1 net.ipv6.conf.eth0.accept_ra = 1   Will the machine now accept Router Advertisements on eth0, or will it not?


Prove that $\cos(\pi/7)$ is root of equation $8x^3-4x^2-4x+1=0$

Prove that $\cos\theta$ is root of equation $8x^3-4x^2-4x+1=0$, given $\theta=\frac{\pi}{7}$.   I put $\cos\theta$ in equation, but couldn't show the left-hand side to be zero.


How can I get enough space for fractions?

\begin{center} \begin{tabular}{|c|c|c|} \hline & polarity & $\displaystyle \frac{\textrm{charge}}{\textrm{mass}}$\\ \hline \textbf{A} & negative & $\displaystyle \frac{E}{g}$\\ \textbf{B} & negative & $\displaystyle \frac{g}{E}$\\ \textbf{C} & positive & $\displaystyle \frac{E}{g}$\\ \textbf{D} & positive & $\displaystyle \frac{g}{E}$\\ \hline \end{tabular} \end{center}


How many elements in $\mathrm{Sym}(9)$ have order $7$?

If I have a symmetric group on $9$ letters, how many elements in the group have order $7$?  I’ve started off thinking about the disjoint cycles, so in cyclic form the only elements can be $7,1,1$ to get order $7$ (as sum of cycles has to equal $9$ but lcm has to equal $7$).  So I started to think about permutations of it. And I’m stuck there.


Make a Windows 10 iso bootable usb using Ubuntu 16.04

I used 16.04.1 for a day, i had some problems and now i want to return to Windows 10. I dont have access to a Windows device. I'm downloading the Windows ISO right now, while searching for Rufus alternatives. I havent found an explained solution on this after searching for like 20-30 minutes. This was my first time on Linux, and i dont know much about making a bootable usb on Linux.   What should i do, which programs and how?


Refractive index and wavelength relation

In general, the refractive index of a certain medium tends to decrease with increasing wavelength.  But are there any materials in which the opposite phenomenon occurs? That is, in which the refractive index increases with increasing wavelength (which would lead to an "inverted" spectrum, if a light beam reached said material)?


how to calculate $\int_C \frac{2xy^2dx-2yx^2dy}{x^2+y^2}$ using green theorm or directly

Calculate $$\int_C \frac{2xy^2dx-2yx^2dy}{x^2+y^2},$$ where $C$ is the ellipse $3x^2 +5y^2 = 1$ taken in the positive direction.   I tried to calculate the integral using green theorm.  now i need to build enclosier that doesn't enclose $(0,0)$ i am having hard time guessing what to build.  a circle and ellipse might be perfect but then the domain is not easy to write. can i have hint please ?


Prove there is no nonzero integer solution to $x^2 - 2y^2 = 0$

By a contradiction. Then prove that there is also no nonzero rational solution.    I'm lost in my first proof course. I appreciate any help.


Is there a mechanic for Passive Deception?

Right now I have a situation with a Doppleganger has infiltrated a small section of the group.  It is passing itself off with the intentions of appearing to be someone important to one person and keeping that person alive so it can keep taking surface thoughts.  The question, I'd rather not have to roll Deception anytime something comes up or to tip my hand a bit if there is an Insight check.  I know we have Passive Perception, but I was wondering if the creature could have Passive Deception as well?


If $\pi:E\rightarrow B$ is a vector bundle  (I allow it to be of nonconstant rank), then I want to prove that it is a homotopy equivalence. As a homotopy inverse I propose the zero section $s:B\rightarrow E$. So $\pi s=id_B$ and $s\pi$ is homotopic to $id_E$ by $f:E\times[0,1]\rightarrow E$, $f(e,t)=te+(1-t)s\pi(e)$. Is this correct?


What is Latest version of Firefox for Ubuntu 17.10? I keep getting a warning saying Firefox version 56 is severely outdated.


Changing the default title/author/institution/frametitle font in Beamer

I sadly haven't been able to answer this questions using Google. In beamer, I'd like to make the default font for the entire title page, as well as frame titles, to be the default font from the old  (example ).


How do I calculate the closest power of 2 or 10 a number is?

What is the most efficient way to cacluate the closest power of a 2 or 10 to another number? e.g.  3.5 would return 4 for power of 2 and 1 for power of 10  123 would return 128 for power of 2 and 100 for power of 10  0.24 would return 0.25 for power of 2 and 0.1 for power of 10  I'm just looking for the algorithm and don't mind the language.


i know how to draw axis and everything else except the function here , please give me hint to plot this function    Thanks for the help


How do I assign text from file to a variable with javascript?

Currently I have this and it works:  var markup = '
';     markup += '
This is a title
';     markup += '
This paragraph is really meaningful.
';     markup += '
'; var div_list = document.getElementById('div_list');         div_list.insertAdjacentHTML('beforeend', markup);   I want to move the markup to an html file (text.html). Then I want to assign the html from that file to a variable in my script.js file. The html file is located in the same folder as my script.js file. The main reason I'm doing this is to separate out my html into a file where I can work in html instead of adding all of the markup in my javascript file.  text.html contains the following:

This is a title

This paragraph is really meaningful.

   I simply want to assign that text to a variable in my script.js file. This way I can do something like  var textFromFile = //whatever I have to do to assign the text from text.html var div_list = document.getElementById('div_list');     div_list.insertAdjacentHTML('beforeend', textFromFile);


Shaders Nodes - Attaching and detaching nodes with python

I would like to import an image as a plane, then add a MixShader and a Transparent BSDF, detach the Material Output Surface link, attach the BSDF to the MixShader, to the Material Output, then add the Transparent BSDF to the Mix Shader. Is this possible to do with python coding? I am totally lost. My goal is making the image imported transparent with a script for EEVEE.


Does updating to 17.10 from 17.04 removes all my softwares?

I am currently using 17.04 ubuntu now. Update manager is asking me to update to a new 17.10 version of ubuntu. And I really want to update.  My question is on updating will I loose all my softwares in the current version?


Aliens want to destroy all dogs because they are seen as next step in evolution beyond Man

I read a SF short story years ago, I think it may have been in high school back in the 1970s. Aliens come to earth, to kill all the dogs, because they see Man as destroying himself, and dogs as evolving to take Man's place, thus being a threat to the aliens. Humanity agrees to kill all the dogs to get rid of the aliens, but in fact have taken border collies (?) deep underground in order to save them and ensure that they evolve.  Does anyone know the title/author of this short story?  Thank you in advance for your assistance.


Additive function $f:\mathbb R\to \mathbb R$ that is not continuous.

Let $f:\mathbb R\to \mathbb R$ an additive function, i.e. $f(x+y)=f(x)+f(y)$ for all $x,y$. In particular $f(0)=0$. I had as an exercise that if $f$ is continuous at one point, then $f(x)=xf(1)$, i.e.  it's linear and continuous everywhere. Now, are they additive function that are nowhere continuous ? If yes, could someone provide an example ? I tried by contradiction : i.e. there is $x_n\to 0$ s.t. $f(x_n)\to \pm\infty $. Suppose WLOG $f(x_n)\to +\infty $. Then, for all $m$, there is $n_m$ s.t. $f(x_{n_m})>m$. Now, $$f(x_{n_m})+f(x_{n_{m+1}})=f(x_{n_m})+f(x_{n_{m+1}})>2m+1,$$ but I don't get any contradiction.


MWE:  \documentclass{scrbook}  \usepackage{xeCJK} \setCJKmainfont{SimSun}  \begin{document}  This is mainly an English document.  With a smattering of Chinese: 中文  \end{document}   Error:  The font "SimSun" cannot be found.   Am giving up on pdfTeX (was asking ).  Am making the jump to XeTeX. Which packages should be installed besides xeCJK? And what default fonts are installed with the packages you would recommend?


What's wrong with this digital signature scheme?

With regards to user authentication...   The server sends Alice a randomly chosen number. Alice signs the number and sends the signature back to the server. The server checks the signature using Alice's public key. If it's valid, the server accepts her connection request.   Suppose that Alice uses the same private key to log in to the server and sign her emails. The authentication mechanism signs the bare challenge without hashing, while Alice signs the hash of the email message.   Apparently, the server can forge emails from Alice under this scheme? If so, how could this be prevented?


I was having a walk when the dog suddenly bit me.   My colleague felt 'having a walk' is not appropriate, and that the correct expression is 'going for a walk' or 'taking a walk'.   Why is "having a walk" incorrect?


c++: when using std::vector, getting error: allocating an object of abstract class type

I have looked at other similar threads and this problem is different in the sense that I use std::vector. I have the following codes making use of inheritance in C++.  #include<iostream> #include<vector> using namespace std;  class Vehicle { public:     virtual void brake()=0; };  class Car : public Vehicle { public:     virtual void brake() override; };  void Car::brake() {     cout<<"Brake applied"<<endl; }   When I call brake() in this way it works:  int main() {     Car c;     c.brake(); // Brake applied     return 0; }    However, when I call brake() using the following way, I get the error error: allocating an object of abstract class type 'Vehicle'  int main() {     vector<Vehicle> vehicleList;     vehicleList.push_back(c);     vehicleList.at(0).brake();      return 0; }   Any help on not getting the error?


I have an image, and in order for it to look good i need to make the width bigger that the part of the page where I am suppose to add text, so it gets shifted to the right. Is there a way to center it, even if it is too big (I am fine with it going beyond the margin, but I want to do so equally on both sides). Thank you!   This is my code  \begin{figure}[htbp]      \centering     \includegraphics[width=18cm, height=6cm]{Figure.png}      \caption{Caption}     \label{fig:outflow}  \end{figure}


When I type $\overset{\circ}{Z}^\lambda$ the lambda is placed slightly above and to the right of the circle. Is there a way to make it appear as a superscript on the Z? I tried $\overset{\circ}{Z^\lambda}$, but then the circle is too high and to the right.  As a bizarre aside: a friend uses the exact same code with no problem. However, when I type it into MathOverflow it looks the same as in my compiler (i.e. bad).


Show that $\sum_{n\ge k} {n \brace k} \frac{x^n}{n!}=\frac{\left(e^{x}-1\right)^{k}}{k!}$

Show that the exponential generating function for  Stirling numbers of the second kind is given by the following relation:  $$\sum_{n\ge k} {n \brace k} \frac{x^n}{n!}=\frac{\left(e^{x}-1\right)^{k}}{k!}$$   $$\sum_{n\ge k} {n \brace k} \frac{x^n}{n!}$$ $$=\sum_{k=0}^{\infty} \frac{1}{k!}\sum_{n=k}^{\infty} \frac{x^n}{n!}\sum_{i=0}^{k}\binom{k}{i}\left(k-i\right)^{n}\left(-1\right)^{i} $$ $$=\sum_{k=0}^{\infty} \frac{1}{k!}\sum_{n=k}^{\infty} \frac{x^n}{n!}\sum_{i=0}^{k}\binom{k}{i}\sum_{j=0}^{n}\binom{n}{j}k^j(-i)^{n-j}\left(-1\right)^{i}$$ Another way I tried: $$\sum_{n\ge k} {n \brace k} \frac{\color{red}{x^n}}{n!}$$ $$\sum_{n\ge k}\color{red}{\sum_{i=1}^{x}\binom{x}{i}i!{ n \brace i}}\color{blue}{{n \brace k}} \frac{1}{n!}$$ $$\sum_{k=0}^{\infty}\color{blue}{\frac{1}{k!}}\sum_{n=k}^{\infty}\frac{1}{n!}\sum_{i=1}^{x}\binom{x}{i}i!{ n \brace i}\color{blue}{\sum_{j=0}^{k}\binom{k}{j} (-1)^{j}(k-j)^n}$$ It would be nice if someone show the relation directly.


I am trying to calculate the minimum stopping distance of a car once the brakes are applied. I know that $F = ma$, and the braking force is $F = \mu N = \mu m g$, so $$a = \mu g.$$ Next, by applying the kinematics equation $$v_f^2 - v_i^2 = 2 a x$$ I found $$v^2 = 2 a d$$ where $a$ is the deceleration, $v$ is the initial velocity, and $d$ is the stopping distance. Then $$d = \frac{v^2}{2a} = \frac{v^2}{2 \mu g}.$$ Is this reasoning right?


Number of ways in which $1000$ can be written as a sum of two or more consecutive natural numbers

Find the number of ways in which $1000$ can be written as a sum of two or more consecutive natural numbers.  The number of ways of finding the sum of two or more consecutive number will be 1 less than the number of odd factors of 1000. How?


Honestly I like working in a dark environment (Twilight on my all my editors), and recently I switched from a Windows to Linux (Ubuntu 16.04 with Unity Desktop on a PC). And being a night worker the brightness is a little harmful to my eyes.   I searched for a bit and these were some of the commands I have tried so far after realizing that the GUI is just not giving me what I need - A Dimmer Screen.  $ dconf-editor   A  of the values of the dconf-editor.  $ add-apt-repository ppa:indicator-brightness/ppa $ apt-get update $ apt-get install indicator-brightness   Nothing happened after toggling the new indicator.  $ apt-get install xbacklight $ xbacklight -set 40 $ xbacklight -set 20   Enabled Xbacklight at   $ ls /sys/class/backlight/   acpi_video0  I dont seem to have intel_backlight so I didn't do this last hack on my system.  $ gedit /etc/rc.local echo 900 > /sys/class/backlight/intel_backlight/brightness   I am a little lost. I would like to know if there is any tool that I can use to decrease the brightness on the system as a whole besides this or is there something that I am missing as a Noob user?   I use Screen Dimmer for Firefox, Twilight for my Code Editors and the terminal is already black. It is the window applications like the File Viewer, Libre Office etc that needs to be dimmed down. I would consider getting a darker desktop theme also (if that is possible) as a valid answer.   Thank-you for being patient enough to read through this rather unintentionally long question.


Multiple domain names and with same content. In different language and same

I have multiple domain names with same content. Some with a different language and some with the same. I have a main website with a hotel name that has been around for some years now. I have recently bought websites with a better name related to area.   I don't want to change the main site as it would disrupt business and its doing OK anyway, but I do want to target certain countries better with the new domains with the new TLDs.   I will be using the same content and 2 domains the same language uk & USA. How do I tell google that this is the same website although the domain names are quite different from the original domain?


So I had removed ubuntu from my laptop by formatting the the disk which it was on, but the GRUB isn't gone yet and I can't find the EFI option with cmd as I have formatted disk, help me to remove the grub, please.


phpmyadmin doesn't connection with true data

I install mysql and phpmyadmin and in installation phpmyadmin i add config password is root but in connection with user is root and password is root i have this error


I tried connecting a few PCs to a domain and they all seem to be accessible, however there are no accounts on the domain. How do I add user to a domain using local admin cmd?


How to show that $\lim_{n\rightarrow \infty }(1+\frac{x}{n})^{n}=e^{x}$

I have a problem:  $E(x)=e^x$, $L(x)=\ln (x)$, $E^{-1}(x)=L(x)$.     Show that $\lim_{n\rightarrow \infty }(1+\frac{x}{n})^{n}=e^{x}$   Hint: use $f(t)=\ln (1+xt)$ and look at $f'(0), x\neq 0$.   I found out that $f'(0)=x$, so I can put it in $e^{f'(0)}$, but I don't know how it can help me. Please, can anyone here help me with this problem or give me a link to a good proof. I'm desperate.


Horizontal line of custom length like an —

Is there a way to get a custom-length horizontal line that appears like a "longer em-dash", if you will?


The star for favourites gives the same tool tip text regardless of state

Regardless the state of a favourite star, the tool tip text is:  "Click again to undo".   When deselected, the tool tip text should read   "Click to mark as a favourite".   This follows 's "Don't Make me think" principle.


Is it possible to use overlapped I/O with an anonymous pipe? CreatePipe() does not have any way of specifying FILE_FLAG_OVERLAPPED, so I assume ReadFile() will block, even if I supply an OVERLAPPED-structure.


Let $a_1, a_2, \ldots, a_n \in \mathbb{R}$. Prove that the following inequality holds: $$\sqrt[3]{a_1^3+ a_2^3 +\cdots+a_n^3} \le \sqrt{a_1^2 + a_2^2 +\cdots+a_n^2}$$    I first tried to restrict the inequality to $\mathbb{R}^{+}$ and that's fairly easy to do since:  $$\sqrt[3]{a_1^3+ a_2^3 +\cdots+a_n^3} \le \sqrt[3]{|a_1^3| + |a_2^3| +\cdots+ |a_n^3|}$$  and  $$\sqrt{a_1^2 + a_2^2 +\cdots+a_n^2} = \sqrt{|a_1^2| + |a_2^2| +\cdots+ |a_n^2|}$$  I tried using the Jensen's Inequality on $x^{\frac 32}$ and $x^{\frac 23}$, but the inequality goes in the opposite direction. Also I tried to divide with $n^{\frac12}$ and $n^{\frac13}$ and use the power mean inequality, but again the inequality goes in the opposite direction.  Anyway, I managed to solve it by raising the inequality to sixth power and we get:  $$\sum a_1^6 + 3\sum a_1^4a_2^2 + 6\sum a_1^2a_2^2a_3^2 \ge \sum a_1^6 + 2\sum a_1^3a_2^3$$  Which is true since:  $$a_1^4 a_2^2 + a_1^2 a_2^4 \ge 2a_1^3 a_2^3$$  and all terms on the LHS are positive. But this prove looks kind of messy. Is there any better proof?  Also it's seems that we can extend this inequality to:  $$k_1 \ge k_2 \implies \sqrt[k_1]{a_1^{k_1}+ a_2^{k_1} +\cdots+a_n^{k_1}} \ge \sqrt[k_2]{a_1^{k_2} + a_2^{k_2} +\cdots+a_n^{k_2}}$$ But can we actually do that?


UK Tourist Visa Refusal - Advice for Supporting Documents

Just looking for a bit of advice here.   My girlfriend recently applied and was refused for a tourist (6 month) visitor visa for the UK. She is of Uzbek nationality but is currently living and studying in Lithuania on a temporary residence permit.  She is going to reapply as soon as possible as we were planning to spend summer here together before she was to return for her studies. I am a British citizen by the way.  I was wondering if anyone had any suggestions of supporting documents that should be added this time round when applying that would help strengthen her case.   It seems to me that they do not believe we are together, so would including previous travel tickets, photographs together and a flat contract demonstrating that we have actually lived together help (we lived together in Cyprus for 3 months)?  Last time I included a written and signed letter of declaration stating that she would be staying with me, a copy of a bank statement as proof of address and a photocopy of my drivers licence. Included was also a letter indicating she would be returning for her next study year from her university.  Any help on the situation would be greatly appreciated so that we can rebook the flights as soon as possible.   I've attached the letter she was sent back below as well.  Thanks!