Where is the OpenLayers Plugin in QGIS 2.4?

I want to do a really simple thing: add OpenLayers/Google Maps basemap as WMS layers. I found this answer:    I installed the OpenLayers plugin, restarted QGIS, but under "Plugins" dropdown there is no OpenLayers plugin. Is it a bug? Or I need to do also some other things to add plugin? Or where else I can find this plugin settings?  Probably my question is: how to add world basemap layer to QGIS?


GP 1.2.10(b) The tangent space $T_{(x,x)}(\triangle)$ is the diagonal of $T_x(X) \times T_x(X).$

If $\triangle$ is the diagonal of $X \times X$, show that its tangent space $T_{(x,x)}(\triangle)$ is the diagonal of $T_x(X) \times T_x(X).$   I don't have the slightest idea on how to do this.  By definition, the tangent space of $X$ at $x$ is the image of the map $d\phi_0: \mathbb{R}^k \rightarrow \mathbb{R}^N$, where $x + d\phi_0(v)$ is the best linear approximation to $\phi: V \rightarrow X$ at 0. $\phi: V \rightarrow X$ is a local parametrization around $x$, $X$ sits in $\mathbb{R}^N$ and $V$ is an open set in $\mathbb{R}^k$, and $\phi(0) = x$.  Thanks.


Replaced Win XP on my old desktop with 14.04 which is working fine, should I upgrade to 15.0 - I'm not a programmer, just a basic user - what do I need to know before making the upgrade? Do I just download and instal 15.0 or do I need to uninstall 14.04 first? Thanks for any help.


Thermodynamics and the state postulate: should it be a Fourth Law?

The state postulate is as follows: The state of a simple compressible system is completely specified by two independent, intensive properties. My first question is whether there is any justification for this postulate or whether it is simply an empirical law? That is, why is it not the case that 3 intensive variables are required to fix the state or even 4? If it is an empirical law with no justification and just happens to be a law our universe abides by, then why is it not one of the laws of thermodynamics as it clearly provides foundational value to the field of thermodynamics? My second question pertains to how we can know whether 2 intensive variables are in fact independant. Say temperature $T$ and specific volume $v$ for example. If we are given a thermodynamic problem, how would we know whether these are independent or not? or perhaps specific internal energy $u$ and pressure $P$. Are there certain combinations that are simply always independent of each other or does independence between intensive variables vary from problem to problem and require a full understanding of the problem at hand? Let us take a phase change for example. From my understanding of phase changes, I know that the boiling temperature is dependent on the pressure and hence I won't be able to use $T$ and $P$ as 2 variables to completely specify the state. But how would I know know what combinations of intensive variables will be independent in this case or any other case for that matter? Does it simply require rote memorization of all independent pairs of intensive variables for all thermodynamic problems or is there a more simple way to figure out what is independent and what isn't? I hope this question makes some sense and any help would be most appreciated!


A word that describes a positive form of envy

Is there an English word that's similar to the meaning of envy, but in a positive way? In other words, if "envy" is hoping for the removal of someone else's blessing, what is the word for "wanting the same blessing for yourself but without wanting the blessing to be removed from the possessor"?  Envy = "I hate to see her luxurious house". Word? = "I wish I were as generous as he is".


Can't change permissions on external drive, even though I am the owner. Can't write to it on other computers

I have an external drive that has only my user with read-write (all other groups as read-only).   So when I mount it on another computer, I can't write to it. Yet, even though I am the owner, I can't change permissions to read-write for all, even if I sudo chmod.  Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes 255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00012a16     Device Boot      Start         End      Blocks   Id  System /dev/sdb1               2  1953525167   976762583    7  HPFS/NTFS/exFAT


How to detect and display user's IP address

Looking for a simple script I can install on a password protected page that basically detects and display the viewers IP address.  So that when my client logs on the page to review a design mock up --I want a pop up dialog that displays his IP address to HIM, with maybe a message "Thank you. This IP Address Was Recorded" and an "OK" button to close the dialog box.    This way he's aware (or under the impression) his visit was "recorded".  Nice to have would be if it were actually recorded for me as well, maybe via an email message or in an IP log/time of visit text file (although that seems like it might be getting in over my head code wise)  The ABSOLUTE ULTIMATE solution would be also if I got notified real time when he accesses the password protected page.


I have a Flask server that has server.py set up in the following way  server.py  app = Flask(__name__) app.register_blueprint(mybp) if __name__ == '__main__':     app.config.foo = "bar"   mybp.py  @mybp.route('/', methods=['POST']) def root():     return app.config.foo   test.py  @pytest.fixture def client():     server.app.config['TESTING'] = True     client = server.app.test_client()     client     yield client  def testbp(client):     client.post('/mybp')   When I run the test, I get the following error  E       AttributeError: 'Config' object has no attribute 'foo'   because the configuration hasn't been initialized when running the test.


How long is it safe to drink coffee after brewed?

How many hours/days would you recommend to drink coffee (after brewed) and consider it safe? (For example if you don't want to waste it). What is the difference if it is refrigerated or not?  The question is not about flavor since (I think) it is probably ruined after at most a couple of hours.


Why use least squared solution of linear regression when we can use X inverse?

I know linear regression gets the estimate of beta by minimizing the squared errors. I'm curious why can't I use inverse of X to get the estimate of beta. I know there is errors and etc. but if X inverse exists, can we just estimate the beta using X ^(-1)? X * beta = Y beta = X^(-1) * Y This does not sound right, but I'm not sure how to disprove it either.


The statement below should print afc abc but it prints abc abc instead. I tried many times but every time same result Don't know why this happens could anyone explain and help me?  echo abc|xargs -i{} echo $(echo {}|sed 's/b/f/g') {}


Getting NullPointerException .Please help anyone to solve this problem

I buy an app source code where every thing is ok but when I uploading any video I am getting NullPointerException. Normally My app is a social media app where user upload short videos for entertainment. Stack trace:   java.lang.NullPointerException: Attempt to invoke virtual method 'byte[] java.lang.String.getBytes(java.nio.charset.Charset)' on a null object reference     at com.squareup.okhttp.RequestBody.create(RequestBody.java:55)     at com.squareup.okhttp.MultipartBuilder.addFormDataPart(MultipartBuilder.java:169)     at com.deshbhakt.app.ApiClasses.MultiPartRequest.addString(MultiPartRequest.java:44)     at com.deshbhakt.app.Services.Upload_Service$1.run(Upload_Service.java:146)     at java.lang.Thread.run(Thread.java:764)  this is RequestBody.java from 46-58 public static RequestBody create(MediaType contentType, String content) {     Charset charset = Util.UTF_8;     if (contentType != null) {       charset = contentType.charset();       if (charset == null) {         charset = Util.UTF_8;         contentType = MediaType.parse(contentType + "; charset=utf-8");       }     }     byte[] bytes = content.getBytes(charset);     return create(contentType, bytes);   }  this is MultipartBuilder.java from 166-170   /** Add a form data part to the body. */   public MultipartBuilder addFormDataPart(String name, String value) {     return addFormDataPart(name, null, RequestBody.create(null, value));   }  this is MultiPartRequest.java from 43-45   public void addString(String name, String value) {         this.builder.addFormDataPart(name, value);     }  this is Upload_Service.java from 146-153  request.addString("user_id", Variables.user_id);                         request.addString("sound_id", Variables.Selected_sound_id);                         request.addString("description", description);                         request.addString("privacy_type", privacy_type);                         request.addString("allow_comments", allow_comment);                         request.addString("allow_duet", allow_duet);                         request.addString("hashtags_json", hashtags_json);                         request.addString("users_json", users_json);


Derivation of formula for electric field strength

I'm currently studying Cambridge A-Levels Based on the definition of electric field strength in the textbook, in which electric field strength at a point is the force per unit charge exerted on a charge at the point, the equation E = F/Q can be derived. However, there is another formula which can be derived: E = -V/d which I don't know how to derive. Any help would be greatly appreciated, Thanks !


Is there any way to "hit with an attack" without making an attack roll?

The PH is clear about what counts as an attack:     If there's ever any question whether something you're doing counts as an attack, the rule is simple: if you're making an attack roll, you're making an attack   However, it's a general principle, and we know that specific beats general. Are there any specific cases in 5e when you actually performing an attack (that will trigger any "when you hit with an attack" feature) without making an attack roll?  Grapple and Shove doesn't count — they , so technically they are not "attacks", despite they are called "special melee attacks" in the PH.  Related:


Increasing Productivity When SSH into Multiple Hosts

I work in operations and need to be able to log into multiple servers among a few hundred servers in a productive way. What I mean by productive is this: from the time from when someone asks me to look at a series of hosts to the time I actually get in to the hosts should be minimal.  Right now I have to go look at my notes, find the host names, add my username in front, put the series of hosts in a text editor and paste that command into the terminal, which gets very tedious.    Ideally I can make some function I can call from the termial that'll help me filter through my host list and find the ones I need, add my username and create my ssh(or ) command.  I've thought about having the following text file:  description           hostname          user .........             .........         ...   and using cat to find the hosts I need, and concatenate the user@ to the front and creating the command.  I feel that there is a better way out there and I'd like to see people's opinion on this.  Thanks for your time!


How to sum up the series of x + 1/x + 1/(x + 1/x) + 1/(x + 1/x + 1/(x + 1/x)) for some finite number of terms?

I'm having trouble in coming up with a formula for this series:  $$S = x + \frac1x + \cfrac1{x + \frac1x} + \cfrac1{x + \frac1x + \cfrac1{x + \frac1x}} +\cfrac1{x + \frac1x + \cfrac1{x + \frac1x} + \cfrac1{x + \frac1x + \cfrac1{x + \frac1x}} } + \cdots + a_n $$  How can I find $S$ ?  Thanks :)


I got this one from Demidovich's "Problems and exercises in Calculus".  I tried to rewrite this as  $$\sqrt{(\sqrt{a^2}-\sqrt{b^2})^2} \le \sqrt{(a-b)^2} \\ \Leftrightarrow \sqrt{a^2-2\sqrt{(ab)^2}+b^2} \le \sqrt{a^2-2ab+b^2} \\ \Leftrightarrow a^2-2ab+b^2 \le a^2-2ab+b^2$$  This certainly proves that they are equal but one isn't lesser than the other... is it correct? It looks like something is missing. If it's correct, then why $\le$ and not "="?


Is there a way to prevent URLs from appearing in biblatex citations?

I'd like to customize verbose biblatex citations to exclude URLs (and DOIs) while keeping them in the bibliography. Is there a simple way to accomplish this?  While I'm at it, I'd like to get rid of the "In: " that the verbose styles use (in both the bibliography and citations), and put the URLs and DOIs on separate lines in the bibliography.


Ubuntu Gnome shortcuts triggered on-press and not on-release

I've noticed that on my Ubuntu Gnome 16.04 LTS all ubuntu shortcuts are triggered on-press instead of on-release. This makes using them with other programs pretty annoying e.g. I'm using two layouts for the keyboard, so I can switch between them with Alt + Shift. In Eclipse however I would like to use the Alt+Shift+X to open Run menu. With current configuration of Ubuntu, the moment I press Alt+Shift+X in Eclipse, I automatically switch keyboard layout.   Is it possible to switch this behavior somehow? Or do I need to remap the shortcuts so there would be no conflicts?


Can I refuse to answer stupid questions at immigration?

Is it legal for customs and immigration officers to ask me the reason I travelled out of the country and return the same day?


Here maps Android SDK crash when setting MapMarker icon with setBitmap

Using the Here maps Android starter sdk, I need to rotate a MapMarker in real time to mirror the rotation (yaw) of a real drone. Because the Here maps Android sdk doesn't appear to have a way to set the rotation for a marker (setRotation with google maps), I rotate the marker's icon with my own code then call setIcon() on the marker with a new Bitmap everytime it needs to be updated. However it seems to randomly cause this crash in the Here drawing code, is there any way to prevent this crash from happening?  E/BaseTextureView( 3916): ******** GL Thread crash ********Thread[BaseTextureView-RenderThread,5,main] W/System.err( 3916): java.lang.NullPointerException: Attempt to invoke virtual method 'int java.nio.Buffer.capacity()' on a null object reference W/System.err( 3916):    at com.here.android.mpa.internal.ae.d(GLBitmapDrawable.java:170) W/System.err( 3916):    at com.here.android.mpa.internal.ae.a(GLBitmapDrawable.java:128) W/System.err( 3916):    at com.here.android.mpa.internal.bf.a(MapMarkerImpl.java:216) W/System.err( 3916):    at com.here.android.mpa.internal.ad.d(GLBitMapTileRenderer.java:682) W/System.err( 3916):    at com.here.android.mpa.internal.ad.onDrawFrame(GLBitMapTileRenderer.java:1024) W/System.err( 3916):    at com.here.android.mpa.internal.m$a.run(BaseTextureView.java:377) E/BaseTextureView( 3916): ******** GL Thread crash ********Thread[BaseTextureView-RenderThread,5,main]


Where is Gnome #1 in the Stranger Things game?

I am nearly at 100% and just need one more gnome! I can’t find gnome #1! Can anyone help?


Can someone explain the reasoning behind Cantor's diagonal argument?

I'm taking a class that's covering cardinalities, and I was introduced to Cantor's diagonal argument today, and I'm having trouble following the logic.  The theorem states, "If s[1], s[2], … , s[n], … is any enumeration of elements from T, then there is always an element s of T which corresponds to no s[n] in the enumeration."  This sounds more like a logical paradox than a theorem to me.  Specifically, it states that "By construction, s differs from each s[n], since their nth digits differ. Hence, s cannot occur in the enumeration." (from Wikipedia)  However, if s[..] is "any enumeration of elements" in T, then it follows that any s created by choosing elements of T, by whatever method, must occur as some s[n], because s[..] represents every combination of digits possible, right?  This is where I can no longer follow the logic of the proof.  Where does the assumption come from, that this diagonal sequence of digits is somehow special and doesn't occur anywhere else in s[..]?  Wouldn't that invalidate the first statement of the theorem?  Sorry if this question seems obvious or stupid, but I can't find an explanation that doesn't seem (to me) to invalidate itself.


If $Z\thicksim\text{Poisson}(\lambda)$, find the expected value of $\frac{1}{1+Z}.$

The Problem: Suppose that $Z\thicksim\text{Poisson}(\lambda)$. Find the expected value of $\dfrac{1}{1+Z}.$  We have that \begin{align*} E\left[\frac{1}{1+Z}\right]&=\sum_{k=0}^\infty\frac{1}{1+k}\frac{e^{-\lambda}\lambda^k}{k!}=e^{-\lambda}\sum_{k=0}^\infty\frac{\lambda^k}{(k+1)!}=\frac{e^{-\lambda}}{\lambda}\left[\sum_{k=0}^\infty\frac{\lambda^k}{k!}-1\right]\\ &=\frac{e^{-\lambda}}{\lambda}[e^\lambda-1]=\frac{1}{\lambda}-\frac{e^{-\lambda}}{\lambda}, \end{align*} where we used the Taylor series for the exponential function.    Do you agree with my approach above? Any feedback is most welcomed. Thank you very much for your time.


Let $D$ be a UFD such that Bezout's Identity holds. Then Every ideal is finitely generated implies that $D$ is PID

My proof $I=<a_1,\dots,a_n>=Da_1+Da_2+\cdots +Da_n$ let $g=gcd(a_1,\dots,a_n)$ Then since Bezout's identity holds and the binary operator gcd is associative, $g\in I$. Also any element of $I$ is divisible by $g$. Thus $I=<g>$ and hence $D$ is PID  I have two questions, is the proof correct? and Where did I use the fact that $D$ is UFD? I think $D$ being Integral Domain with identity is enough as well.


Permutations of a string with duplicate characters

I have a string ABCCEF and I want to find the number of permutations not counting the duplicates. I ran a piece of python code     len(set([''.join(i) for i in itertools.permutations('ABCCEF')]))   and the output was 360. This piece of code determines all the permutations of ABCCEF (including the duplicates), creates a set of the permutations, then spits out the length of that set.  I am really rusty in the subject of combinatorics but through the magic guess and check, I BELIEVE that the value 360 is determined from  5*4*3*3*2*1 = 360   I determined this from the string have 6 values but only 5 unique values. So on the first slot I have 5 options to choose from, then 4, then 3. then 3 again (2 C's), then 2, then 1.  I dont really have a firm grasp of this concept. I was wondering if anyone could point out flaws in my logic and/or help me with a better process to solve this problem. Pretty much explain to me why I am correct...OR WRONG!


Hello i recently tried to install steam on ubuntu on 64-bit desktop version didn't work ,so i tried server version 64-bit still didn't work. I saw somebody say that steam is only 32-bit so i tried 32-bit server version but still got same result. I use  Raspberry Pi 4 Model B; 4 GB, ARM-Cortex-A72 4 x, 1.50 GHz, 4 GB RAM.    ubuntu@ubuntu:~$ sudo apt install steam Reading package lists... Done Building dependency tree        Reading state information... Done Package steam is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source However the following packages replace it:   steam-devices  E: Package 'steam' has no installation candidate  so i tried this solution:  didn't work ubuntu@ubuntu:~$ sudo dpkg --add-architecture i386 ubuntu@ubuntu:~$    i am stuck here a don't know what to do.


MySQL query where result of one column row is added with next one

I have used a query  which is like  SELECT app_id, SUM(amount), date  FROM abc  GROUP BY app_id,date   Result is show as follows  1   10   1-2-2000 2   20   1-2-2000 3   30   1-2-2000 1   20   2-2-2000 2   40   2-2-2000 3   50   2-2-2000   I want to get desired result with new column  1   10   1-2-2000 2   30   1-2-2000   # sum of amount of app_id=1 and app_id=2 3   60   1-2-2000   # sum of amount of app_id=1 and app_id=2 and app_id=3 1   20   2-2-2000 2   60   2-2-2000   # sum of amount of app_id=1 and app_id=2 3  110   2-2-2000   # sum of amount of app_id=1 and app_id=2 and app_id=3


What would be the most technically unaltered/numerically close camera-to-monitor workflow using common software?

If the intention was to, as much as possible, shove the ADC output octets that were present in the camera right up the framebuffer and out the HDMI cable - possibly truncating LSBs, if possible discarding (or averaging) one of two green channels and simply mapping the three remaining pixels of a bayer quad to the rgb channels of a monitor pixel each (no advanced demosaicing) - ... how would one have, in general terms, to set up a camera, typical software (Rawtherapee, LR etc), and the computer?  I admit this question is half academic, but could help clarify the confusion about what is most unaltered in a digital workflow, and help with lens comparisons etc.


After installing SQL Server 2019 CU2, SQL Server Agent stops working

After installing SQL Server 2019 CU2, SQL Server Agent starts consuming too much CPU resulting into skip job schedules.  Although the agent service is running but it looks like hang and didn't process / kick off any jobs.  Once I re-start the Agent service it starts working again (cpu = 0), but then again after some time 1-2 hours CPU intake in high and jobs do not run.  Is anybody else facing same issue with SQL Server 2019 CU2?  Any help would be much appreciated.  Thanks,


Is $\mathbb{C}$ equal to $\mathbb{R}^2$?

Complex numbers are usually formally defined as pairs of real numbers. Although there are operations on $\mathbb{C}$, such as complex multiplication, which are not found in operations usually applied to $\mathbb{R}^2$, the sets themselves seem to be the same. Each consists of pairs of real numbers.  So is it okay to say that $\mathbb{C} = \mathbb{R}^2$? It seems formally correct, but something doesn't feel quite right about it.


Programming Languages for Bioinformatics

Good day everyone,  I am very much interested in math, biology, and programming; ideally I would like to study bioinformatics and, as such, was wondering what languages are typically used by bioinformaticians? Particularly for fields of bioinformatics relevant to biochemistry, virology, and immunology, what are the most useful programming languages to know, as well as their strengths and limitations? (i.e. in what setting would it be better to program in C++ than Python, is R good to know and if so why, etc.)  Thank you in advance.


Why can I not edit a method that contains an anonymous method in the debugger?

So, every time I have written a lambda expression or anonymous method inside a method that I did not get quite right, I am forced to recompile and restart the entire application or unit test framework in order to fix it. This is seriously annoying, and I end up wasting more time than I saved by using these constructs in the first place. It is so bad that I try to stay away from them if I can, even though Linq and lambdas are among my favourite C# features.  I suppose there is a good technical reason for why it is this way, and perhaps someone knows? Furthermore, does anyone know if it will be fixed in VS2010?  Thanks.


I have an audio mixing desk that I need a power supply for.   The output required is 16.8VAC 1.4 amperes. The original is discontinued but I have found one for sale that is rated 17VAC 1.2 amperes and one that is 18 VAC 2.0 amperes. Is the lower current rating a problem with the first and is the extra voltage a problem with the second?


I am trying to prove the estimate for $a,b\in \mathbb{R^n}, p\geq 1$ $$|a+b|^p\leq C(|a|^p+|b|^p)$$ where $C$ is a constant depending only on $p$. I am able to do it when $p$ is a natural number. But, could you give me any hints on how to do it for any $p\geq 1$?


i'm currently on Ubuntu 20 and i wanted to dual boot with cent-OS but i only have a one hard disk and somehow i couldn't manage to create a separate partition in Ubuntu to install centos it on. i tried to use gparted tool but it didn't allow me to create partition even though i never created a part before ever since i installed Ubuntu. and i was wondering that if i tried to install cent and then create a partition for it from inside the custom partitioning tool it offers during installation, will that erase my current data or it will install it self on a free space ??


How to include JavaScript script only on specific page

I am creating my own widget. I need to use custom css and js files. I have used wp_register_style`wp_enqueue_styleandwp_register_script\wp_enqueue_script` functions in order to register custom styles and scripts.     I implemented this in following way.  function __construct() {         // parent constructor         add_action( 'wp_enqueue_scripts',array( $this,'init_widget')); }  public function init_widget() {     wp_register_style( 'accordion-category-style', plugins_url('accordion-category-style.css', __FILE__) );     wp_enqueue_style( 'accordion-category-style' );     // Register the script like this for a plugin:     wp_enqueue_script('jquery');     wp_register_script( 'accordion-category-script', plugins_url( 'accordion-categories.js', __FILE__ ) );     wp_enqueue_script( 'accordion-category-script' ); }   And this works perfectly, but one problem that these files are included on each page of the site.   But I only need to include on page where my widget is visible. Is it possible to achieve such behavior ?   SOLUTION   I tried to use solution suggested by @jdm2112 , but I used not the accepted answer from his link but just checking inside widget method like this and this works   public function widget( $args, $instance ) {     if ( is_active_widget(false, false, $this->id_base,true) ) {         $this->init_widget();     }    One issue is this adds scripts in the middle of html page not at the top.


How do I make my glasses look realistic?

I've been stuck for quite a while, it just looks wrong you can surely tell. I'm kinda new to blender, here's a picture:  Q: How can I improve the glass shader?


How to limit the network bandwidth usage in Virtual box

I am using Virtual box 5.1.22 on Ubuntu 16.04. I need to limit the bandwidth of the Internet connection (more precisely the upload speed) being used by an application running on Windows 7(a Virtual machine) in Virtual box. Is there a way to do that? Thanks in advance


How to create a full circle vector that its fill/stroke color changes along the path?

I would like to know how to color change a stroke in Illustrator or Photoshop like the Q in the picture:


The positive integer solutions for $2^a+3^b=5^c$

What are the positive integer solutions to  the equation     $$2^a + 3^b = 5^c$$    Of course $(1,\space 1, \space 1)$ is a solution.


What are some of the best Physics resources online?

Are there any sites similar to (in terms of function and quality) Paul's Online Math Notes, 17Calculus.com, or PatrickJMT.com, for Physics (besides Khan Academy)?  I've googled this, but the sites I've found were described as high-school level, and I'm not sure if these would be adequate/appropriate for getting help for a college physics course.  I'm aware of and a frequent user of Khan Academy, but I'm hoping to find recommendations for additional resources.    Edit: I can see how it might seem this question duplicates , but it is different. Here's why:  I'm not seeking to learn physics online—I'm a college student who just began Physics I, and I'm looking for physics resources, similar to supplemental resources like Paul's Online Math Notes or 17calculus.com you might visit if you were studying calculus.  I've googled this before asking my question, naturally, but the resources I found were either geared towards high-school students, or they were in formats, such as forums, that aren't conducive to systematic learning/studying. I also explored this site looking for similar questions that might have the answers I'm seeking, but I did not find any that were directly in line with the sort of well-organized, systematic approach that makes it easy to find and follow information pertinent to that which you're currently studying. PatrickJMT.com is another example of the sort of site I had in mind; only the publisher focuses primarily on calculus and only touches briefly on physics problems.   If more advanced users community say the high-school resources are adequate for helping a student in a college Physics I course, that'd be great!  Otherwise, I was merely hoping for some recommendations for well-organized resources designed and/or appropriate for supplementing a conventional course, similar to the abundant resources you'd find for mathematics.  If you'd reopen my question, it would benefit not only me, but also huge numbers of other people who are or will be studying physics. Thanks!


If $\lambda$ is a real eigenvalue of a real matrix $M$, does there necessarily exist a real eigenvector of $M$ corresponding to $\lambda$?  Edit: Never mind. I figured it out.. If $\lambda$ is a real eigenvalue, then $\det(\lambda I-M)=0$, which means there exists a real vector $x$ such that $Mx=\lambda x$. Right?


can lines be labelled to make referring to them dynamic?

I am using the listings package to document code in a LaTeX document and have line numbering turned on to be able to refer to specific sections in the code. Most changes to the code being documented, something that occurs quite frequently, necessarily mess up the references to line numbers in the accompanying text. Is there a way to make these references to line numbers dynamic, i.e. does the listings package provide a way of identifying lines with labels? I skimmed through the documentation once again, but nothing leaped at me.


What happens when Illusory Gains is detached during combat?

Player 1 has  onto the battlefield. Player 2 has  onto the battlefield. In Player 2's main phase, he cast  on Arcades Sabboth, to gain control of the Elder Dragon; and, in the subsequent combat phase, declares Arcades Sabboth as an attacker, tapping him. In the declaring blockers sub-phase, the defending player (player 1) summons Plaxmanta - spending green mana - thanks to his Flash Ability.  Consequently, this question arises, which I am now going to explain in detail.     Since Illusory Gains' triggered ability is now on the stack, and the creature to which Illusory Gains is to be assigned is the just summoned Plaxmanta, I was wondering which of the two is the right one:  1) Arcades Sabboth continues to be tapped and attacking, as declared by player 2 during the sub-phase, and therefore remains on his side, until the end of the combat phase; or,     2) Arcades Sabboth, since Illusory Gains has been "detached", is no longer under the control of player 2, and returns under the control of player 1, but tapped and removed from the fight.  In all this situation, Plaxmanta is in any case now enchanted by Illusory Gains, and therefore it is under the control of player 2. But it is good to clarify whether the combat phase has significantly changed since his entering onto the battlefield, in a case like the one described.    And for this purpose my question is addressed.  The particular dynamics of Illusory Gains, namely the fact that this card can "detach" from one creature to enchant another in various situations, makes this question a little different from various others, in my opinion.   Also the fact that Illusory Gains can be attached to creatures that have hexproof or shroud makes this card - and the situations related to it - really particular, and therefore it may need more explanations and clarifications from expert players.


$f:X\rightarrow Y$, with $Y$ compact, is continuous $\Rightarrow$ its graph is closed

Let $X,Y$ topological spaces, $f:X\rightarrow Y$ a function, with $Y$ compact. I need to show that, if $f$ is continuous, so $$G_{f}:=\{(x,f(x)):x\in X\}$$ is closed in $X\times Y$.  I saw that question with $Y$ Hausdorff, so is easy to prove that for every $(x,y)$ with $y\neq f(x)$, there is an open set $U\times V$ such that $U\times V\subset (G_{f})^{c}$ by taking a neighborhood $V$ of $y$ in $Y$ with $f(x)\notin V$.   Can I do that for $Y$ compact? If not, how can I solve this question?


Probability of a painted cube being reassembled into itself

Suppose 27 cubes are stacked together, suspended in the air, to form a larger cube.  The cube is then painted on all the exposed surfaces and dried.  The smaller cubes are then randomly permuted in both spatial position and spatial orientation to form another large cube.  What is the probability that new larger cube is identical to the original?  This is not homework, it was passed on by a friend who found it somewhere on the internet, and they do not remember where.


What XP do you lose when you exit a game mid play?

I was wondering what you lose of the XP and progress you have made from the round you disconnect from.


I rarely see someone I know or I rarely see anyone I know?

Lots of people have been moving out of my hometown. I rarely have seen anyone I know.   Can you use "someone" instead of anyone?  If not, please explain why. Thank you!


linux patches related to time measurement accuracy?

Is there a set of patches around for linux kernel that address accuracy of (system, rather than user) process time?  i've heard about RTLinux, but i don't really need the actual real-time scheduling constraints, i just need that the time measurements are accurate. If the process switch slipped by a couple milliseconds, so be it, but i need an accurate measurement of the actual time spent in the current process


CSS3's border-radius property and border-collapse:collapse don't mix. How can I use border-radius to create a collapsed table with rounded corners?

Edit - Original Title: Is there an alternative way to achieve border-collapse:collapse in CSS (in order to have a collapsed, rounded corner table)?  Since it turns out that simply getting the table's borders to collapse does not solve the root problem, I have updated the title to better reflect the discussion.  I am trying to make a table with rounded corners using the CSS3 border-radius property. The table styles I'm using look something like this:  table {     -moz-border-radius:10px;     -webkit-border-radius:10px;     border-radius:10px }   Here's the problem. I also want to set the border-collapse:collapse property, and when that is set border-radius no longer works. Is there a CSS-based way I can get the same effect as border-collapse:collapse without actually using it?  Edits:  I've made a simple page to demonstrate the problem  (Firefox/Safari only).  It seems that a large part of the problem is that setting the table to have rounded corners does not affect the corners of the corner td elements. If the table was all one color, this wouldn't be a problem since I could just make the top and bottom td corners rounded for the first and last row respectively. However, I am using different background colors for the table to differentiate the headings and for striping, so the inner td elements would show their rounded corners as well.  Summary of proposed solutions:  Surrounding the table with another element with round corners doesn't work because the table's square corners "bleed through."  Specifying border width to 0 doesn't collapse the table.  Bottom td corners still square after setting cellspacing to zero.  Using JavaScript instead- works by avoiding the problem.  Possible solutions:  The tables are generated in PHP, so I could just apply a different class to each of the outer th/tds and style each corner separately. I'd rather not do this, since it's not very elegant and a bit of a pain to apply to multiple tables, so please keep suggestions coming.  Possible solution 2 is to use JavaScript (jQuery, specifically) to style the corners. This solution also works, but still not quite what I'm looking for (I know I'm picky). I have two reservations:    this is a very lightweight site, and I'd like to keep JavaScript to the barest minimum  part of the appeal that using border-radius has for me is graceful degradation and progressive enhancement. By using border-radius for all rounded corners, I hope to have a consistently rounded site in CSS3-capable browsers and a consistently square site in others (I'm looking at you, IE).   I know that trying to do this with CSS3 today may seem needless, but I have my reasons. I would also like to point out that this problem is a result of the w3c specification, not poor CSS3 support, so any solution will still be relevant and useful when CSS3 has more widespread support.


Allow specific windows applications to update from user account with no local administrator rights

I am managing a small network of about 15 Windows 8.1 computers/users. None of these users have local admin rights (because I don't want to spend 24 hours a day removing viruses and malware from the computers)  We use a softphone for communication from a company called 8x8. The software is great and does NOT require admin rights to run, however, they do put out new releases about once a month or so. When this happens, in order to upgrade the software to the latest version, I have to physically go to the computer and use a local administrator password to allow the upgrade to occur.   I am hoping there is a way to essentially "trust" or "whitelist" a specific running program to allow that program to be upgraded directly from the local user account (who does not have admin access)  For what it is worth, this specific software does check for updates and starts the update from (what appears to me) to be inside of the program. Meaning, I do not have to go to a website, download a .exe file and run it. If this was the case, I can see where it might be harder, since I doubt there is a way to whitelist a certain .exe file by name or something like that.  Any ideas?


Suppose that $x_n \leq y_n, \forall n$. Show that $\sup x_n \leq \sup y_n$. I would like to prove this by contradiction but am slightly stuck as how to go about doing this.  I started off with sssuming that $$\sup x_n = x > \sup y_n = y.$$  Then we have that $\forall 0 < \epsilon < x - y$, $\exists N$ such that $\forall n \geq N$, we have $$0 < y - y_n < \epsilon < x - y.$$  I am stuck here and any help would be greatly appreciated.


Difference between “him” and “his” in these sentences?

What is the exact difference in meaning of following sentences:        I understand his quitting.   I understand him quitting.


Is there a POSIX (or at least a popular) utility to set the current working directory when invoking a program?

We have  to modify the environment of the command we want to run (for example env MANPAGER=more man dtrace). Is there something similar but for modifying the directory that the command is going to be started in?  Ideally, I would like it to look like this:  theMagicCommand /new/cwd myProgram   This way it could be "chained" with other env(1)-like commands, e.g.,  daemon -p /tmp/pid env VAR=value theMagicCommand /new/cwd myProgram     So far I can think of the following solution, which unfortunately does not have the same interface as env(1):  cd /new/cwd && myProgram   Also, I can just create a simple shell script like this:  #! /bin/sh - cd "${1:?Missing the new working directory}" || exit 1 shift exec "${@:?Missing the command to run}"   but I am looking for something that already exists (at least on macOS and FreeBSD).  myProgram is not necessarily a desktop application (in which case I could just use the ).


I have found out the .tar.gz for my printer but i do not know which one to download from the list. plz tell me which one to download and how to install..  Here's the link   I use lubuntu 14.04


Orders of Growth between Polynomial and Exponential

What is known in contemporary mathematics about orders of growth for functions that exceed any degree polynomial, but fall short of exponential?   This is a subject for which I've found little literature in the past.  An example: $Ae^{a\sqrt x}$ clearly will outrun any finite degree polynomial, but will be outrun by $Be^{bx}$.     If we replace $x$ with $y^2$ then that example doesn't seem so deep. Are there functions that exceed polynomial growth yet fall short of $Ae^{ax^p}$ for any power $0<p<1$?     What classes of functions can we distinguish with different kinds of in-between orders of growth?   What can we know about their power series expansions, or behavior in the complex plane?   Those are examples of the kinds of questions I have, and would like to find literature on.  Have any definitions or terminology been established concerning this?  The right jargon will facilitate searching.


share internet connection (via hotspot) with a lan with ieee 802.1X encryption

my dorm internet is protected with IEEE 802.1X encryption (Microsoft PEAP) and I want to share the connection with my phone, but so far, I haven't been able to do it. I can create the hotspot, but the phone doesn't connect to the internet. Is there any way to share it?   It is not that I don't know how to create a hotspot, I've been using it at home during last year, but now, I've moved to a new home and to access the internet I need to configure a proxy and use my username and password for university and also it is protected with verification according to the standard IEEE 802.1x and Protocol PEAP, so even if I create the hotspot and connect to it, the phone/other computer/tablet/whatever can't go to internet.  I need something to tell the hotspot to go through the proxy and authentication, because I think that's the problem  These are the instructions for windows  in case I couldn't make myself clear enough


can my niece travel to the uk using her greek id card after brexit

my niece is due to travel for a visit in April 2019 for 3 weeks to the uk and we are a bit concerned about what travel documents she can travel on due to the uk leaving the EU with or without a deal on the 29th of march any help would be appreciated.


Derive an explicit formula for a power series $\sum_{n=1}^\infty n^2x^n$

Could anyone help me find an explicit formula for:  $$ \sum_{n=1}^\infty n^2x^n $$  We're supposed to use: $$\sum_{n=1}^\infty nx^n = \frac{x}{(1-x)^2}  \qquad  |x| <1 $$


How to easily reorder rows in excel with drag and drop or move-up or move-down?

I have to do some manual reordering or rows in Excel and cut/paste is too hard to use. I'm looking for something that would enable me to use drag'n'drop or to add some buttons to move-up/down move-top/bottom.


Java: Does "==" only check for reference to an object?

So I was taught that “==”  only checks whether they are the same object and “equals()” checks the values of the objects.  But for Strings, I found that “==” also checks for values. For example:-      String x = "apple";     String y = "orange";     x=y;      if (x==y){         System.out.println("yes");     }else{         System.out.println("no");     }  //OUTPUT: yes   or  String x = "apple"; String y = "apple"; y = "watermelon";     if (x==y){         System.out.println("yes");     }else{         System.out.println("no");     }tem.out.println("no");     //OUTPUT: no


Over half our board and staff [are/is] people of color?

I'm under the impression that the correct verb to use is "are," but my colleagues believe it to be "is."  And what about just: "over half our board [are/is] people of color" ?  Another case: "over half the stadium [are/is] people of color"  We're tripping over these examples, any help appreciated!


after a little bit working, I found that Singapore style is preferable for my needs. Anyway the problem is still there.   I tried to include the mini-frame bullets in the sidebar using  \useoutertheme[subsection=false]{miniframes}  I added it to the preamble of my swp, which now looks like:  \newenvironment{stepenumerate}{\begin{enumerate}[<+->]}{\end{enumerate}} \newenvironment{stepenumerate}{\begin{enumerate}[<+->]}{\end{enumerate}} \newenvironment{stepitemize}{\begin{itemize}[<+->]}{\end{itemize} } \newenvironment{stepenumeratewithalert}{\begin{enumerate}[<+-| alert@+>]}{\end{enumerate}} \newenvironment{stepitemizewithalert}{\begin{itemize}[<+-| alert@+>]}{\end{itemize}} \usetheme{Singapore} \definecolor{unime}{rgb}{.93,.9,.0} \usecolortheme[named=unime]{structure} \setbeamerfont{footnote}{size=\tiny} \useoutertheme{split} \setbeamertemplate { items } [ball] \definecolor{lside}{rgb}{.7,.0,.0} \definecolor{leftFootlineColor}{rgb}{.54,.17, .89} \useoutertheme{sidebar} \setbeamercolor{frametitle}{bg=unime} \setbeamercolor{section in head/foot}{bg=leftFootlineColor} \logo {\includegraphics[scale=0.35]{uni}} \setbeamertemplate{sidebar canvas left} [vertical shading] [top=lside, bottom=lside] \useoutertheme[subsection=false]{miniframes} \DeclareGraphicsExtensions{.pdf,.png,.jpg} \graphicspath{ {c:/} } \input{tcilatex}   The output looks like this:    What I would like is to have the mini-frames bullets in the sidebar on the left instead of the name of each subsection. This would be more convenient if each section contains many subsections.   I hope I explained my case better now.   Thanks   Dario


Ubuntu 18.04 LTS Macbook Pro - Live Disk Boot Trouble AND regular boot trouble

I was running Ubuntu 17.10 on my mac (mid-2010) as a dual-boot with Refind as the boot manager. It was functional albeit non-optimal drivers for wifi and video card.  A day ago, the Software Updater app gave me the option to upgrade and I took it. It completed the install and clean up fully but I was unable to do a final restart due to power issues. Anyway, after the power issues were sorted out, I booted my laptop, only to find that it wouldn't boot into the OS and would get stuck in a loop at a screen which was filled with lines of code that made no sense to me.  So, I rebooted with option key and booted into recovery mode and ran check disk and fix broken packages and then resumed boot. Then it booted into the OS fine. I rebooted again, and then it went back to the screen with lots of lines of code which no sense. I tried the same thing again with the recovery mode again. And this time when it booted I picked the proprietary Nvidia drivers. Now when I boot, there is just a blank screen and I cant boot into recovery mode either because there is an error in EFI screen option.  So I boot into OS X and download the ISO file for 18.04 and make a bootable USB stick and boot into that from the EFI screen. Now, it boots and once past the orangeish blue bionic beaver wallpapers, it gets stuck in a loop at a message called setting locale.  So, at this point, I can neither boot into my HDD Ubuntu install nor into the Live Disk.  My next plan of action is to try and get an ISO of a previous version and try booting form that. I'd like to avoid that if possible and stick to 18.04.  EDIT 1: I flashed Ubuntu 17.10 onto the USB storage, and that boots fine. I'll try 18.04 once again. Also, I'm using Unetbootin for flashing the USB storage.  EDIT 2: This keeps cycling over and over when I live booted from a freshly downloaded copy of Ubuntu 18.04 ISO file flashed in to a USB:    Keep in mind that when I do this on the same USB with the ISO file for 17.10.1, live boots perfectly fine.   EDIT 3: I've given up. I'm doing a clean install of 17.10.


I've tried at least 4 times on  to add the tag css-columns, but each time after I save it disappears. When I type it in the tag box, it shows up and even has a tag wiki associated with it, but it will not stick when I save.


to run latest emacs in terminal by typing "emacs"

Question:  Because I use emacs-live, I used homebrew to install emacs-24.3. Now everytime I want to launch emacs of version 24.3 in terminal, I have to type "emacs-24.3" --- if I just type "emacs", it launches the original updated emacs came with Mac OS.  how can I configure these so that I only need to type "emacs" and launch the one installed by homebrew?  I use emacs in terminal, so the workaround that installing GUI version of emacs is not the solution what I am looking for. I use OSX Lion.  Note:  Solved the issue by ! the point was to restart my terminal after doing what you guys suggested...  For future visitors I will just post full procedure for solving this issue.  Solution:   Add following line in .bash_profile: PATH="/usr/local/bin:$PATH" as  post explained. Close the terminal and restart again. If you don't restart, you will be stuck as I did :-)


I'm currently using Windows Xp need to keep it on and install Ubuntu 14.04 LTS can I keep both OS on one HDD dual boot?I wouldn't with virtual box.


Favicon best practices regarding size and format

I'm busy on a WordPress site and have come to the stage to add the finishing touch, being the favicon. I'm primarily a developer so graphics and icons aren't my strongest point.   What are the best practices when creating a favicon (in terms of sizes etc, I already have the design)? I'd like to accommodate for every possible device, be it mobile, tablets, retina displays etc. Also I don't want it ending up blurry so I need to know what pixel density to use and everything.  If there are some Mac apps or online tools that will do this for you (and do it properly) that would be great as well. Otherwise I know how to find my way around Illustrator and Photoshop.


If I stop a long running query, does it rollback?

A query that is used to loop through 17 millions records to remove duplicates  has been running now for about 16 hours and I wanted to know if the query is stopped right now if it will finalize the delete statements or if it has been deleting while running this query? Indeed, if I do stop it, does it finalize the deletes or rolls back?  I have found that when I do a    select count(*) from myTable   That the rows that it returns (while doing this query) is about 5 less than what the starting row count was. Obviously the server resources are extremely poor, so does that mean that this process has taken 16 hours to find 5 duplicates (when there are actually thousands), and this could be running for days?  This query took 6 seconds on 2000 rows of test data, and it works great on that set of data, so I figured it would take 15 hours for the complete set.  Any ideas?  Below is the query:  --Declare the looping variable DECLARE @LoopVar char(10)       DECLARE      --Set private variables that will be used throughout       @long DECIMAL,       @lat DECIMAL,       @phoneNumber char(10),       @businessname varchar(64),       @winner char(10)      SET @LoopVar = (SELECT MIN(RecordID) FROM MyTable)      WHILE @LoopVar is not null     BEGIN        --initialize the private variables (essentially this is a .ctor)       SELECT          @long = null,         @lat = null,         @businessname = null,         @phoneNumber = null,         @winner = null        -- load data from the row declared when setting @LoopVar         SELECT         @long = longitude,         @lat = latitude,         @businessname = BusinessName,         @phoneNumber = Phone       FROM MyTable       WHERE RecordID = @LoopVar        --find the winning row with that data. The winning row means        SELECT top 1 @Winner = RecordID       FROM MyTable       WHERE @long = longitude         AND @lat = latitude         AND @businessname = BusinessName         AND @phoneNumber = Phone       ORDER BY         CASE WHEN webAddress is not null THEN 1 ELSE 2 END,         CASE WHEN caption1 is not null THEN 1 ELSE 2 END,         CASE WHEN caption2 is not null THEN 1 ELSE 2 END,         RecordID        --delete any losers.       DELETE FROM MyTable       WHERE @long = longitude         AND @lat = latitude         AND @businessname = BusinessName         AND @phoneNumber = Phone         AND @winner != RecordID        -- prep the next loop value to go ahead and perform the next duplicate query.       SET @LoopVar = (SELECT MIN(RecordID)      FROM MyTable     WHERE @LoopVar < RecordID)     END


Pair-wise iteration in C# or sliding window enumerator

If I have an IEnumerable like:  string[] items = new string[] { "a", "b", "c", "d" };   I would like to loop thru all the pairs of consecutive items (sliding window of size 2). Which would be   ("a","b"), ("b", "c"), ("c", "d")   My solution was is this       public static IEnumerable<Pair<T, T>> Pairs(IEnumerable<T> enumerable) {         IEnumerator<T> e = enumerable.GetEnumerator(); e.MoveNext();         T current = e.Current;         while ( e.MoveNext() ) {             T next = e.Current;             yield return new Pair<T, T>(current, next);             current = next;         }     }   // used like this :  foreach (Pair<String,String> pair in IterTools<String>.Pairs(items)) {     System.Out.PrintLine("{0}, {1}", pair.First, pair.Second)  }   When I wrote this code, I wondered if there are already functions in the .NET framework that do the same thing and do it not just for pairs but for any size tuples.  IMHO there should be a nice way to do this kind of sliding window operations.  I use C# 2.0 and I can imagine that with C# 3.0 (w/ LINQ) there are more (and nicer) ways to do this, but I'm primarily interested in C# 2.0 solutions. Though, I will also appreciate C# 3.0 solutions.


Give a bijection from $\omega^{\omega}\to\Bbb N$

Question Give a bijection from $\Bbb N\to\omega^{\omega}$ Where $\omega^{\omega}$ is the set of ordinals expressible in Cantor normal form as: $$\sum_{i=k}^0\omega^i\cdot a_i:a_i\in\Bbb N_{\geq0}$$ Attempt 1 A close try is to let $a_i$  count the number of consecutive ones and twos in an integer's binary representation: $27=11011_2\mapsto\omega^2\cdot2+\omega+2$ But since there are no zero-length sequences of ones or twos in binary representations, this is unable to represent any ordinal having a finitely long sequence of consecutive zero coefficients. Attempt 2 One might think of just reducing each coefficient by $1$ like this: $27=11011_2\mapsto\omega^2+1$ This now represents zero coefficients, but it fails to inject because it gives the same ordinal $0$ for all the following numbers: $S_n=1,2,5,10,21,42,85,\ldots$. Attempt 3 Ideally I'd like to fix this approach rather than take a new approach altogether.  I'm not sure how to proceed but I have a rough hunch we might be able to add or multiply a number (which may not truly be an ordinal) of the following form or similar: $$\beta=\sum_{i=0}^\infty\omega^{2i+k}\cdot$$ but I'm all out of ideas really, beyond that.


Is the algorithm for choosing Pro Tempore moderators on new sites fair?

I come from Startups SE, a fairly new site which just got out of private beta about a month ago. My use of the site has dwindled in the last few weeks, as I took some personal effect to an interesting choice of moderators which I and many others found surprising. Forgive me for sounding selfish - clearly I am. But I just want to make this clear. The post given on startups meta, which I'm sure is referenced all over, includes the following block as criteria for being selected for a Pro Tempore moderator position:   Have a reasonably high reputation score to indicate active, consistent participation. Show an interest in their meta’s community-building activities. Lead by example, showing patience and respect for their fellow community members in everything they write. Exhibit those intangible traits discussed in A Theory of Moderation.  Bonus points for:  Members with participation in both meta and the parent site (i.e. interest in both community building and expertise in the field). Area 51 participation, social network referrals, or blogging about the site. Members who have already shown an interest or ability to promote their community. Candidates will be contacted and three of them will be selected to act as provisional Moderators until the community holds formal elections after the Beta period.  Besides the normal abilities of a Moderator, they will:  Have access to a special chat room where we will collectively work through the challenges of moderation and community self-policing. Organize the process of selecting the site’s attributes (domain names, design issues, the [help center], etc.). Rally community support and drive the mission of getting publicity for the site. Essentially, they will have the ear of the Stack Exchange team for anything we can do to help their sites succeed!   First off - wow. This sounds amazing. When I first read this meta post, I was so excited. I worked as hard as I could to place as best I could in the process. Just a few notes to consider here:  Out of the 4 nominated persons, I tied for the second most community votes with 6 votes, one of them being a moderator from a different network (7-6-6-2 - having upvoted all other three candidates)  I led the site with more reputation than the second and third combined (2300 vs 1400 and 800). I was second most active in edits and the most active in reviews. I logged on around 50 times every day (yeah I'm obsessed but that's kind of my point).  I was the most active member in the chat and provided knowledgeable answers in short amounts of time to those seeking information (this was undisputed among anyone from startups)  I followed and asked questions on Area 51, having been part of the earliest phase to get startups initiated.   So my biggest question - what did I do wrong? I've heard from many people on the network that it is because my reputation on Stack Overflow is low, or that I didn't have high reputation on another one of the networks. If this is the case, I have three words for this community: shame on you! If one communicates on a network where he or she has to be adept in two industries to moderate the one he or she excels in, what kind of ill representation is this of the real specialized world we live in? A few points - telling me that "you wouldn't like being a moderator" or "if you're that active, the community needs you doing other things than being a moderator" seem totally moot and invalid to me. Yes - I'm selfish, but I'm concerned I was misled and I would like any future try-hards like myself to better know what to expect if they want to become a pro-temp moderator. I know it's just a Stack Exchange site but I felt at home there, and honestly I did take it personally. I know I won't get any condolences and I don't need them - I just don't want anyone else to experience the pain I did.


Just wondering if there is an update to the problem of ubuntu touch not working on toro phones, and if not I am curious if it will ever be supported. I know the mobile phone market progresses at a rapid speed and people are focusing on the edge project.


When I record a screen with a standard QuickTime Player functionality, I get a completely green video. I'm using Mac OS X 10.8, Mountain Lion, and a Retina MacBook Pro 15".  Does anybody know what is the issue and how it can be fixed?


I'd like to count up List's size by element. For example,  List<String> source = Arrays.asList("USA", "USA", "Japan", "China", "China", "USA", "USA");   I'd like to create object (Map) from this source, such as,  int usa_count = result.get("USA").intValue(); // == 4 int javan_count = result.get("Japan").intValue(); // == 1 int china_count = result.get("China").intValue(); // == 2 int uk_count = result.get("UK").intValue(); // == 0 or NPE (both OK)   Now, I composed below.  Map<String, Integer> result = new HashMap<>(); for (String str : source) {     Integer i = result.getOrDefault(str, Integer.valueOf(0));     result.put(str, i + 1); }   Though, this is enough to my purpose, I think this is not elegant code, and I wanna be a elegant coder. I use Java8. Is there any elegant solution instead of my solution?


how should the "select all" select when paginating elements

Suppose I have a list of 100+ pieces of data that I'm displaying in a table that's paginating 40 elements per page.  Each row has 'select' checkbox that enables the user to select/unselect an individual item. On top of the list, there's also a 'select/unselect all' checkbox. For the moment, I have the functionality designed so that when the user clicks that checkbox, the action of toggling the selection is performed only on the elements currently displayed in the page. What are the best practices on 'select all'?  Should the action operate on:   a) only the visible elements being paginated, or   b) the entire list?


A bee inside a car - An application of Newton's laws

This is a situation based question and I don't know whether is it directly connected to physics or not. Sorry, if not, I thought that it would be best to ask it here, of it has some interesting application.  Anyways, I recently started to learn Newtonian mechanics as a high school student and recently learnt about laws of motion.  Now consider this situation which I have encountered many times. The situation is that I'm inside car and car is moving, window are open and suddenly a fly enters the car and it is pretty comfortable inside (making us disturbed). Now I wonder how the bee is managing inside the car. What I mean here is that we are having a velocity because we are in contact with car(as we are seated on the seat and not flying) whereas the bee is apparently, not in contact with car and hence should not possess the velocity of car ( I deliberately said that windows are open, because may be closing of windows affect the motion of bee, which I neither know nor experienced), but the bee is flying here and there annd this according to road frame must have a velocity greater than car, which is of course not the case ( I searched speed of a bee on browser and found it to be around 10-15 miles per hour, which is way less than speed of car, I am in.  So what's the reason for this result. May be it's biological, which I don't think and I considered this situation from physics's viewpoint, with conditions idealized. So according to me the bee should be thrown back to the end of car, because there is no considerable friction and as per the law of inertia. Other thing which I considered was pressure, which I came to conclusion can surely not change as windows are open. I'm not able to go beyond.  May be the question seems stupid, but the real aim of physics is understanding real situations and not completely idealized ones. So, I would appreciate any help on how to analyse this situation and to know what is going on from a physicist point of view.  EDIT In the other question, the conditions are different from mine. There windows are closed and here open, which may make a difference, I suppose. Also I didn't found a satisfactory answer there, so I posted it on the basis of my common experience.  Thanks a lot.


Kernel PCA for feature selection for various machine learning algorithms

I would like to forecast stock index returns with SVM, k-NN, and Neural Networks. In advance I want to select my inputs via kernel PCA (kPCA). Everything is performed in R. For the KPCA I use kernlab.   The data which I preprocess to the KPCA are various lagged input variables, where I want to identify the most explanatory lags through the KPCA. It is in xts format originally but for the KPCA I convert it to matrix.   Is there anybody who can tell me how I find out which of the original variables in the xts data matrix are considered to be most explanatory by the KPCA? Yet I am able to perform KPCA but I cannot interpret any results of it.  I have read the documentary of kernlab, so that did not help.


Split a file into multiple based on selected lines

I have a file in which more than 50,000 lines are there. How can I split the file into two or more based on the selected lines?  Suppose I want to split a file from line 10,000 to line 40,000.


What's the meaning of "as it did" in this sentence?

Islamic law is the result of an examination, from a religious angle, of legal subject matter that was far from uniform, comprising as it did the various components of the laws of pre-Islamic Arabia and numerous legal elements taken over from the non-Arabnpeoples of the conquered territories.


How to get the Milky Way bright enough without overexposing foreground objects?

I went out and captured the Milky Way and because I have a 18mm-55mm 1: f3.5 5.5 lens I had to turn the camera sideways and stitch them together in photoshop and just having to work with what I got at the moment until I can afford something better but I was really happy with how it turned out! but I'd like to take it to the next step and maybe have a foreground or myself in the picture. So this brings me to the question, How do people capture the Milky Way/stars with themselves in it so clearly or sitting around the fire without it being over exposed. Is this through post processing and how do they do this, I can't necessarily completely understand how to do it. Such like these:


How many calories does a home-made marinade add?

I'm planning on marinating my chicken legs with Tabasco sauce. I have read that a marinade should be one part lemon juice and 3 parts olive oil.  I'm going to be using two skinned chicken legs, lemon juice, extra virgin olive oil and Tabasco sauce  The reason I want to marinate the chicken legs is because I will be eating them on the go and wont have time to add the Tabasco sauce to them yet I still want them spicy.  So basically I'm wondering how many extra calories could I be talking for each chicken leg.  Thank you.


how can i write latex code to produce this rectangle as picture

anyone can help me this question,i really hurry,


Even though mm is a shortened form of millimeter, would mm be written as 'an mm' or 'a mm', given that m starts with an 'e' sound.


How to create a circular badge with lines as spokes?

I need to replicate this look. How would I go about doing so in either Photoshop or Illustrator?


My brother tried to open a .lnk file with 7zip and now every shortcut tries to open in 7zip, how do i undo this or fix this? I genuinely have no idea what to do or where to start and no one else appears to have had a similar problem.


I have a website that I would like to monetize with Adsense. I keep receiving the same feedback from Adsense when submitting :  Site Behavior: Navigation As stated in our Program policies, sites or apps displaying Google ads should provide substantial and useful information to the user. Users should be able to easily navigate through the site or app to find what products, goods, or services are promised. Examples of misguided navigation include, but are not limited to:  False claims of downloadable or streaming content Linking to content that does not exist Redirecting users to irrelevant and/or misleading webpages Text on a page unrelated to the topic and/or business model of the website.   I submitted the web site multiple times, trying to solve potentially problematic issues but I keep receiving the same feedback. Do anyone have experience in solving similar issues or have an idea what I should do ? The url of the site is : sun dash direction dot com


What exactly IS voltage and its difference to other measurements of electricity?

I apologize if this is a stupid question, but I cannot find any answers online, so I feel I must ask here.  I do not quite understand exactly what voltage is. I see on batteries, "X Volts", but I do not quite know what that means. I looked online and read sources on volts, amperes, and watts, and it has only confused me more. What exactly is voltage? If it isn't a measure of the electric current, then why is it used on batteries as a measure of their electric power? Why aren't amperes used?


Should I download the Hardware drivers that Windows Provides or drivers from Manufacturer's website?

today I've installed Windows 8.1 and everything is working as it should be but I'm stuck at installing the Graphic drivers, I have a Dell Inspiron 5537 with AMD Radeon HD 8670M, I've found a driver on Dell Support for my laptop graphic driver, but on AMD website I've found an Up-to-date driver for my Radeon HD 8670M, also Windows Update provides a driver.. So the question is     Should I download the driver from Dell website, or   AMD Website, or Windows Update?


Call a function from a stored string in Python

What I need is something that gets the variable and if the variable is the name of a function, the function will be called. I am not trying to get a function from a module but from within the program itself  Example:  def foo():     print("Foo") callfunction = input("What function do you want to call? ")  callfunction() ## Not sure what to put here but but lets say callfunction is foo.   I don't want something like this because I have many functions:  if callfunction == "Foo"     Foo() else:     print("No function with that name")   My question is something like , but I ask for the Python syntax. I am using Python 3.5.1


If we can construct lines of distance $1$ and $x$, then how do we construct a line of distance $x^2$?

The author is trying to prove it is impossible to square a circle of radius $1$ under the assumption that $\pi$ is transcendental. Even with this assumption, the author explains that if the circle can be squared, then we could draw a line with distance $\pi^{1/2}$. Everything good at the moment. Then he claims that, if such construction is possible, we could also draw a line of distance $\pi$, and that the proof would, under the stated assumption, be complete.     The thing I don't get is how, from a line with distance $\pi^{1/2}$, we could create a line with distance $\pi$.


What is this optical phenomenon, as looked from outer space?

I just saw a photo from NASA. This is it.    This is beautiful. But i am not being able to understand, what are those red and green lines above the earth surface? These cannot be due to Rayleigh scattering of course as there are no particles to do that.   Moreover, just above the surface of the earth, we see a blue colour( which is very faint ) . Is this due to Rayleigh scattering?   PS- I can assure you, that these are not photographic effects, so please don’t take it into account.


is there a way to define a function that takes two lists and makes the elements in the first list the key and the elements in the second list the values of a dictionary?  names = ['ted','west','tom','jerry','fred'] and another list ages = [10,23,13,18,12] how can i define a function that takes the two lists and returns a dictionary with the names as the key and the scores as the value?   i know that i can turn each list into a dictionary and then append it but I'm not sure how i can place the colons.


Remmina doesn't work with keyboard when connected remotely

In order to bypass firewall/GPO constraint, I want to use Ubuntu as springboard to rdp to a Windows box on the same LAN remotely. I can xrdp to ubuntu via sesman-Xvnc module. I can run remmina from the vnc session. But in the remmina Windows session, keyboard doesn't work at all. Only mouse works. Keyboard works with other apps in vnc session. Also, if I use remmina at local Ubuntu console, keyboard works.  Any suggestions?


If $G=H\times K$ then can we view $G/K$ as $H$?

Here $K$ is identified as $\{1\}\times K$. I think because $G/K$ does not depend on $H$, it is natural to say that $G/K$ and $H$ is isomorphic.


How to differentiate this negative power?

I'm reading the book "Calculus made easy" and I'm stuck with a step of a derivative with a negative power. Here is what is in the book:     Case of a negative power.      Let $y=x^{-2}$. Then proceed as before $$\eqalign{y+dy&=(x+dx)^{-2}\\&=x^{-2}\left(1+\dfrac{dx}x\right)^{-2}.}$$   I don't understand what I have to do to go from  $$ (x+dx)^{-2} $$ to $$ x^{-2} \cdot (1+dx/x)^{-2} $$ Any help will be much appreciated!


I am using GNOME Terminal but, I am not able to make it transparent. Am I missing some packages?  I am using the latest gnome 3.18, so I dont think its a DUP issue.


I found many results, but i didn't get any solution for Ip's. I want to find the user ip details all over the world by using php, but not able to find it.


I'm currently doing a couple of exercises on logarithmic expressions, and I was a bit confused when presented with the following: $5^{\log_5 17}$.  The answer is $17$, which is the argument of the logarithm in the exponent, but I don't understand the reason why.  A previous question in the exercise was $12^{\log_{12} 144}$, which is pretty straight forward since $\log_{12} 144=2$ and $12^2=144$ but since $\log_5 17$ is an irrational number, I couldn't calculate it the same way.  So my question is, why is $x^{\log_x n}=n$?  [Update]  I've now managed to reason this out and realized how simple it is.  Basically, if $y=\log_x n$, then $y$ is the number that  $x$ must be raised to to become $n$; therefore, if I raise $x$ to that power $y$, I will naturally get $n$.  I guess my problem was that I tried to work out the question mechanically instead of intelligently and that's why I failed, because once I realized that I can't calculate $\log_5 17$, I was stumped.  Now that I reasoned it out, as explained in the previous paragraph, I understand it.


I am having date field in the UI. I have written code as per below      Datetime XXX = (Datetime)FieldName;     yyy= XXX.format('yyyyMMdd');   But after executing the batch date is decremented by 1 automatically  Can anyone suggest some idea??  Thanks in advance.


If I squeeze something really hard, will it ever become two-dimensional?

A mosquito just wanted to bite me! Päng - and it stuck to my hand, hardly recognisable anymore. I said to my girlfriend: "Just reduced the dimension of the mosquito by one!"  Therefore the question: If I squeeze a three-dimensional body really hard, will it ever become two-dimensional?  Two-dimensional means that it has a thickness of 0, so 1 atom layer is not 2D.  edit: I'd like to make this question a bit more general: Are there any real two dimensional objects or phonemes in a 3D (or 4D) world?


Where to ask a question about computer science and programming study advice?

What Stack Exchange site would a question like this be appropriate for?  I'm a student in my 3rd year of college studying computer science and programming. So far I have studied a lot of stuff, but I mostly "specialize" in Java web development and Android. I've done lots of projects with Android and Spring, and I'm even going to an internship for those fields. Even though I like those things, I'm not sure if that's what I want to do for the rest of my life. During my 4th year, I will learn a bit more about data science and AI. So the questions are:  Do people transition from one technology and programming field to another during their careers, let's say from full stack developer to data science? How many things can I do at once. I know I can pretty much work on both Java web projects and Android. Should I even try to incorporate another language/technology, lets say should I try and incorporate data science as well?


Counter-example: any algebraic extension is finite

I just proved that any finite extension of fields is an algebraic extension. That is, given fields $F,K$ such that $K \subseteq F$ is a subfield then if we can view $F$ as a vector space over $K$ with finite base, then any element of $F$ is the root of a polynomial with coefficients in $K$.   I was told that the converse is not true. Do you know any example where an extension is algebraic but not finite?


I have an application that does this : When the application starts,one row with 3 editTexts is created by calling a method called newproduct().The first of them is focused and this triggers the creation of another row of those 3 edittexts.So,when the last row is focused,another row is created dynamically. Every columns is inside a different linear layout and gets added to a new ArrayList<EditText>();,one for everyone of the 3 columns.The values that get entered are then put inside a String[],again,3 of them for every column.  My questions now are the following : 1.How can i save this on screen orientation changes? When i change the orientation,the values remain but only in two of the rows because those 2 rows are created at onCreate( newproduct method called,creates the first row, and then focused,so it creates another row).How can i tell my application to create more then 2 rows and keep the values ?  2.How can i make my application keep everything,the number of rows and their values and the whole UI layout when the user either exits the app or the app crashes.What i want here is when he enters the app again to see the state in which the app was left the last time.  Thanks in advance and have a nice day !


Get the radio value without refreshing the page

I want to make a form that sends a feedback (good/average/poor) in a mysql database without loading the page I'm on. It's working fine except that it doesn't recognize if wich value I'm sending (if it's good, average or poor that was sent).  Here my form :  <form method="post" id="radio_fb" style="margin-top:-90px;">
         <input type="radio" name="radios" id="poor" value="poor" />Poor         <input type="radio" name="radios" id="average" value="average" checked="checked" />Average         <input type="radio" name="radios" id="good" value="good" />Good         <input type="hidden" name="url" value="<?php echo 'http://'.$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI'];?> "/>         <input type="submit" name="submitter" value="Send" id="submit" />
 </form>   And here is my jQuery :  jQuery(document).ready(function($) {     $("#radio_fb").submit(function() {         cname = this.radios.value;         curl = this.url.value;         submitter = this.submitter;          var data = {             name: cname,             url: curl         };         $.post("ajax.php", data, function() {             submitter.value="Sent";             submitter.disabled=true;                     });          return false;      }); });   And here are the functions that store the value in the database:  <?php include_once('config.php');  if ($_POST['radios'] == 'good') {     $url = $_POST['url'];     $bdd->exec('INSERT INTO feedback(id, url, avis) VALUES ("", "'. $url .'", "Good")'); } else if ($_POST['radios'] == 'average') {     $url = $_POST['url'];     $bdd->exec('INSERT INTO feedback(id, url, avis) VALUES ("", "'. $url .'", "Average")'); } else {     $url = $_POST['url'];     $bdd->exec('INSERT INTO feedback(id, url, avis) VALUES ("", "'. $url .'", "Poor")'); }  ?>   Any idea how to fix this? I looked through all the answers but nothing is working: my function keeps returning the else statement (or nothing if I remove it).


I began the ubuntu upgrade before leaving for work and returned to something broken.  After some efforts to get more information to fix this problem I've done the following:  >sudo apt-get dist-upgrade Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt-get -f install' to correct these. The following packages have unmet dependencies:  ia32-libs : Depends: ia32-libs-multiarch but it is not installable  libc6-dbg : Depends: libc6 (= 2.19-0ubuntu6.6) but 2.19-10ubuntu2.3 is installed  libpcre3-dev : Depends: libpcre3 (= 1:8.31-2ubuntu2) but 1:8.35-3ubuntu1 is installed  skype : Depends: skype-bin but it is not installable E: Unmet dependencies. Try using -f.   So try -f...  >sudo apt-get -f install Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following extra packages will be installed:   libc6-dbg libpcre3-dev libpcrecpp0 The following packages will be REMOVED:  ia32-libs skype The following packages will be upgraded:   libc6-dbg libpcre3-dev libpcrecpp0 3 upgraded, 0 newly installed, 2 to remove and 1649 not upgraded. 160 not fully installed or removed. Need to get 0 B/3,799 kB of archives. After this operation, 242 kB of additional disk space will be used. Do you want to continue? [Y/n] y E: Sub-process /usr/bin/dpkg returned an error code (2)   Check dpkg...  >sudo dpkg dpkg: error: configuration error: /etc/dpkg/dpkg.cfg.d/multiarch:1: unknown option 'foreign-architecture'   Can someone advise please?


Let $f:A \rightarrow B$ and C ⊂A. Define f[C]={b∈B: b=f(a) for some a∈C}. Prove or disprove each of the statement

Let $f\colon A \to B$ and $C \subset A$. Define $f[C]=\{b∈B : b=f(a) \text{ for some } a \in C\}$. Prove or disprove each of the statements:  a) If $f$ is a bijection, then $f[A\setminus C] = B\setminus f[C]$.  Let $f$ be a bijection. since $f$ is onto then $f[A]=B$ and since $f$ is 1 to 1 then $f[A\setminus C] = B\setminus f[C]$ since every $A$ correspond to a $B$ and every $C$ correspond to some $f[C]$ so you remove that part from $B$.  Is this correct?I'm not sure if this is enough or all i need. Is there a more concise proof?   b)If $f[A\setminus C] = B\setminus f[C]$ for every $C \subset A$, then $f$ is a bijection  I'm not sure how to do this one. do I say that do I say this need to be 1 to 1 so $A$ doesn't make a $f[C]$. Any help would be great. Thanks!


Upgrade script cannot find newer release

One of my servers is unable to upgrade from Ubuntu 12.10 (Quantal Quetzal) to newer versions:  $ cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=12.10 DISTRIB_CODENAME=quantal DISTRIB_DESCRIPTION="Ubuntu 12.10"  $ cat /etc/update-manager/release-upgrades | grep -v '^$\|^\s*\#' [DEFAULT] Prompt=normal   (also tried with Prompt=lts)  $sudo apt-get update ...  $sudo apt-get dist-upgrade Reading package lists... Done Building dependency tree Reading state information... Done Calculating upgrade... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.  $ sudo do-release-upgrade -d Checking for a new ubuntu release No new release found   Tried to change servers to http://old-releases.ubuntu.com (got from ), and from digitalOcean but result is the same.  Eventually I upgraded this server using the following steps:   Backup /etc/apt/sources.list file Changed original servers to  Changed all quantal to raring in /etc/apt/sources.list file Updated package lists (apt-get update) Updated packages (apt-get dist-upgrade) - everything completed smoothly Rebooted server Checked for new distribution (sudo do-release-upgrade -d) - still not found Changed raring to saucy  in /etc/apt/sources.list file Repeated steps 4-7 with same results Restored backed-up /etc/apt/sources.list file Changed saucy to trusty  in /etc/apt/sources.list file Repeated steps 4-7 with same results   Now I have Ubuntu 14.04 LTS (Trusty Tahr) release. It is OK until 2019-04, but it still cannot find upgrades.  Is there a way to restore the ability of an Ubuntu distribution to upgrade using the do-release-upgrade script?  Command line solution is highly preferred.


Identify an unidentified device in windows 7 without opening up the computer?

If I go to Device Manager and click on the device I am trying to connect, the device properties does not always (almost never) list the actual device name and model. Is there any way to identify unidentified devices for which I will later find drivers for on Google?


Fit regression model from a fan-shaped relation, in R

I get a fan-shaped scatter plot of the relation between two different quantitative variables:    I am trying to fit a linear model for this relation. I think I should apply some kind of transformation to the variables in order to unify the ascent variance in the relation before fitting a linear regression model, but I can't find the way to do it. Or maybe, there is a better model to use in these cases, I can't either find it.  I have tried rlm, but the residuals still have heteroscedasticity. I have also tried to apply a SD ratio calculated from all the y of each x and other similar erratic approaches.  My questions:   Is there any typical way of fitting a model for a fan-shaped relation or a typical model to use in these cases? Is there any typical transformation that could be applied to the variables in order to reduce its variance?


I need to extract from string      userAllowedCrud['create']   the part that is inside [].   i think using regular expression is the better way to do it. Am i wrong?


Can we fix the grammar on the "possible duplicate" comment?

When closing a question as a dupe, the system generates a comment:     possible duplicate of  --     Can we get a capital P and a period on this comment, please? I find myself editing the comment afterwards for two characters.  I know this is a nitpick, but it's still something that could be fixed.


How do I unset an element's CSS attribute using jQuery?

If I set a CSS value on a specific element using:  $('#element').css('background-color', '#ccc');   I want to be able to unset that element-specific value and use the cascaded value, along the lines of:  $('#element').css('background-color', null);   But that syntax doesn't seem to work – is this possible using another syntax?  Edit: The value isn't inherited from the parent element – the original values comes from an element-level selector. Sorry for any confusion!


Should I pay off my credit card with savings?

Right now I have about 3k left in credit card debt which I've been steadily paying off.  I could probably have it paid off completely in about 6 months to a year.  However, I already have over 4k in my savings account.  Would there be any benefit to paying it off all at once now, or does it usually make more sense to continue to pay it off incrementally?


git reports "No space left on device", but df -h says there is is 2.5G available

I have an EC2 node running Ubuntu 14.04. On a deploy this morning, I received the following error message from git fetch:  error: unable to create temporary file: No space left on device   I logged into the server and df -h indicates I have plenty of space:  $ df -h Filesystem      Size  Used Avail Use% Mounted on udev            492M   12K  492M   1% /dev tmpfs           100M  488K   99M   1% /run /dev/xvda1      7.8G  4.9G  2.5G  67% / none            4.0K     0  4.0K   0% /sys/fs/cgroup none            5.0M     0  5.0M   0% /run/lock none            497M  4.0K  497M   1% /run/shm none            100M     0  100M   0% /run/user   Am I misreading df here? My understanding has been that /tmp on EC2 is resident on /dev/xvda1, but maybe I'm wrong?


At what point does next Tuesday mean      the next Tuesday that will come to pass     and no longer      the Tuesday after the Tuesday that will come to pass?   And, when does the meaning switch back?


Knowing the interface of ubuntu and editing them

Where are the files for the desktop or the interface that appears on the screen stored? And how can we edit them. How are they programmed?  What programming language is used to built the interfaces?


SQL - Difference between WHERE with two tables and a JOIN

Here are these two SQL queries:  SELECT `o`.`date`, `i`.`description`, `o`.`quantity` FROM `orders` AS `o`, `items` AS `i` WHERE `i`.`itemID` = `o`.`itemID`;   and  SELECT `o`.`date`, `i`.`description`, `o`.`quantity` FROM `orders` AS `o` JOIN `items` AS `i` ON `i`.`itemID` = `o`.`itemID`;   I get one result less with the first one. Can someone explain the difference between the two?


How to create strings containing double quotes in Excel formulas?

How can I construct the following string in an Excel formula:     Maurice "The Rocket" Richard   If I'm using single quotes, it's trivial = "Maurice 'The Rocket' Richard" but what about double quotes?


Difference between "I reached home" and "I have reached home"

I often confuse these two things: "I reached home" and "I have reached home". Once my friend asked me, "Where are you? "  I messaged him: "I have reached home". He told me not to use "have reached "...     reached = past tense, have reached = present perfect   Can someone please clear this doubt so that I don't make the mistake again.


Prove the following and use it to evaluate the integral:

I want to prove that:$$\int_{-\infty}^\infty f(x)dx=\int_{-\infty}^\infty f\left(x-\frac1x\right)dx$$ And use the result of this proof to evaluate:$$\int_{-\infty}^\infty\frac{x^2}{x^4+1}dx$$


Diagonalizable operator $D$ on $R^3$ and a nilpotent operator $N$

Let T be the linear operator on R3 which is represented by the matrix  $\begin{pmatrix} 3  &1 &-1  \\  2 &2& -1  \\  2 &2& 0  \\ \end{pmatrix}$  in the standard ordered basis. Show that there is a diagonalizable operator $D$ on $R^3$ and a nilpotent operator $N$ on $R^3$ such that $T = D + N$ and $DN = ND$. Find the matrices of $D$ and $N$ in the standard basis.  We have the relationships  $D=c_1E_1+...+c_kE_k$  and  $N=(T-c_1I)E_1+...+(T-c_kI)E_k$  but I do not know how to use it. Can anyone explain? In this case the characteristic polynomial is $(x-1)(x-2)^2$. I do not know if I should find the matrix of E_i, also I did not understand either if In this formula should I consider the repetition of eigenvalue?


How do I get gallery thumbnail URL and change the default thumbnail size?

when I create a gallery I get this code generated yet I can;t find out how  <img width="150" height="150" src="http://localhost/wp2/wp-content/uploads/2012/06/28_0120-150x150.jpg" class="attachment-thumbnail" alt="_28_0120" title="_28_0120">   What function generates the thumbnail URL and how does the thumbnail image generated and cropped to the size of 150-150?  I forgot to mention: for the gallery page I use get_children, so this is what I need to work with


What will happen if rotation of Earth will get reverse?

Today one question pop up into my mind... What will happen if Earth spinning about its axis and around the sun will start moving in reverse direction... Whether it will affect us... What are all things will change?


I am trying to write an buffered image into a file that appends the next buffered image bytes.I have the following code for which some runtime exception is thrown. when i run this code i get the following exception. Why and what has to be changed?   import java.io.File;     import java.io.FileInputStream;     import java.io.FileOutputStream;     import java.io.IOException;     import java.io.InputStream;     import java.io.OutputStream;     import java.awt.image.BufferedImage;     import java.io.ByteArrayInputStream;     import java.io.ByteArrayOutputStream;     import java.io.File;     import java.io.IOException;     import java.io.InputStream;     import javax.imageio.ImageIO;           public class FileT     {         public static void main(String[] args)         {                try {                 BufferedImage originalImage = ImageIO.read(new File("ani.jpg"));                 int i=0,c=0;                 // convert BufferedImage to byte array                 ByteArrayOutputStream baos = new ByteArrayOutputStream();                 ImageIO.write(originalImage, "jpg", baos);                 baos.flush();                 byte[] imageInByte = baos.toByteArray();                 byte[] copybuf = new byte[1024];                 baos.close();                  while(i<imageInByte.length)                 {                     copybuf[c]=imageInByte[i];                     c++;                      if(i%1023==0)                         {                         // convert byte array back to BufferedImage                        InputStream in = new ByteArrayInputStream(copybuf);                        BufferedImage bImageFromConvert = ImageIO.read(in);     ImageIO.write(bImageFromConvert, "jpg", new FileOutputStream(new File("ani1.jpg"),true));                             }                         copybuf = new byte[1024];                         i++;               }             }             catch (IOException e) {                 System.out.println(e.getMessage());             }             }     }     Exception in thread "main" java.lang.IllegalArgumentException: image == null!     at javax.imageio.ImageTypeSpecifier.createFromRenderedImage(ImageTypeSpecifier.java:925)     at javax.imageio.ImageIO.getWriter(ImageIO.java:1592)     at javax.imageio.ImageIO.write(ImageIO.java:1578)     at FileT.main(FileT.java:45)


How can I change the controls in Don't Starve?

How do I change the controls/key bindings on Don't Starve? I can't play using the WASD keys.


WHEN MATCHED clause fails if there's a NULL in the ON columns

I'm using a query with merge that works fine if all columns in the ON clause have a value but WHEN MATCHED omits if there's a NULL mark in one of the columns:  MERGE PEPS AS peps USING (Lots of Cols..        FROM PEPS_temp)  AS temp (Lots of Cols..)  ON peps.[Name] = temp.[Name] AND     peps.[LastName] = temp.[LastName] AND     peps.[TypeEntity] = temp.[TypeEntity] AND    peps.[Source] = temp.[Source] WHEN MATCHED THEN UPDATE SET peps.[Category] = temp.[Category]  WHEN NOT MATCHED THEN INSERT (Lots of Cols..) VALUES (temp.[Col], temp.[Col], temp[Col]....)   Case: I have target table that I update manually first its Category column so I set Category='EX BLOCKED' the source table is the updated list so the clause WHEN MATCHED is supposed to update the Category column to 'BLOCKED' if it exists in the source table, if not WHEN NOT MATCHED inserts the new rows that do not exist.  Query runs successfully and when checking the lists I detect duplicates:  ;WITH Duplicados      AS (Select ROW_NUMBER() OVER  (PARTITION BY Name, LastName, TypeEntity, Source ORDER BY ( SELECT 0)) RowNum, Name, LastName, TypeEntity, Source          FROM [PEPS]) SELECT * FROM Duplicados WHERE  RowNum > 1 AND Source='OFAC SDN';   All the duplicate rows contain NULL marks in at least one of the columns of the ON clause.  Example:


When I compile and run the following code: struct preferences {     bool likesMusic : 1;     bool hasHair : 1;     bool hasInternet : 1;     bool hasDinosaur : 1;     unsigned int numberOfChildren : 4; };  int main() {     struct preferences homer;     homer.likesMusic = true;     homer.hasHair = false;     homer.hasInternet = true;     homer.hasDinosaur = false;     homer.numberOfChildren = 3;          printf("sizeof int: %ld bits\n", sizeof(int) * 8);     printf("sizeof homer: %ld bits\n", sizeof(homer) * 8);     printf("sizeof bool: %ld bits, sizeof unsigned int: %ld bits\n", sizeof(bool) * 8 , sizeof(unsigned int) * 8); }  The output is: sizeof int: 32 bits sizeof homer: 32 bits sizeof bool: 8, sizeof unsigned int: 32.  When I comment out the numberOfChildren field from preferences, the output is: sizeof int: 32 bits sizeof homer: 8 bits sizeof bool: 8, sizeof unsigned int: 32  This does not make sense to me because the size of unsigned int is deduced to be 24 bits from this experimental run as the size of homer struct got reduced from 32 to 8 bits after the removal of numberOfChildren field. Also, the output itself contains sizeof unsigned int: 32. Any insight you can provide would be appreciated. Thanks. My setup is Ubuntu 20.04, 64-bits, Intel architecture Xeon Silver 16-core processor.


How to treat dimensions correctly when multiplying/dividing probabilities?

For two stochastic variables x and y, the rule for independence is given as $$   p(x,y) = p(x) \, p(y)   $$ On the left hand side of this equation is a 2D quantity, and on the right hand side are two 1D quantities. In order for this equality to work, the product must therefore have the form of an outer product. Say that $p(x)$ is a Gaussian probability density representing the voltage drop measured across a (defective) diode, so that $p(x)$ has units of inverse volts. Next say that $p(y)$ is an exponential probability density representing the amount of light (optical power) hitting the diode, and thus has units of inverse watts.  If we were to plot $p(x,y)$ using a computer, then we could sample the distribution at various values of $y$, and would find the Gaussian distribution $p(x)$ scaled in amplitude, reaching a maximum at $y=0$, and tailing off to zero amplitude as $y \to \infty$, but keeping the same overall position and width for all $y$.  So far all of this makes sense, though I have yet to find a textbook that explicitly treats the dimensionality issue. But what if we invert the equation, as many texts do. Then we have $$   p(x) = p(x,y) / p(y)   $$ and the question is: how do we perform this division correctly? We are dividing a 2D quantity by a 1D quantity, and the most logical interpretation would seem to be to do exactly the inverse of an outer product: at each $x$-value, we divide the distribution by $p(y)$, which leaves us with a 2D distribution like $p(x) \cdot \mathbb{1}(y)$. Assuming that $p(y)$ is nowhere zero, we are left with a uniform value in $y$, but we still have a 2D quantity. To get rid of the extra dimension, and to make the equality work, we appear to need an integral over $y$. But $\int \mathbb{1} (y) dy$ is an improper integral, so that we would appear to need to add a $\delta$-function inside the integral.  But this seems absurdly over-reasoned given that this is such a basic point and that the dimensionality issues are treated in no textbook on probability theory that I have been able to find. But how else can one compute the above division, considering that $x$ and $y$ are not in the same space as one another?


How do spacecrafts get a gravitational boost from planets?

I have heard that the Voyager spacecrafts received gravitational boosts from some of the planets before they left the solar system.  How is this achieved?  Since we have to conserve energy it seems that whatever speed is gained due to gravity would then be lost as the object flys away from the planet.   Specifically I want to know how we can willingly slow the planets orbit to steal some of its energy.  How do we know that the fly by is going to take energy from the planet rather than lose energy to the planet?


Remnants of an alien civilisation, vessels with pre-programmed destinations

I read this in the 90's, but I believe that it was older; probably 80's, but possibly even as old as the 50's or 60's. I read it in English or Swedish, but I don't remember which of those. It wasn't an incredibly long story, but long enough to be a novel; probably 250-300 pages. I have no memory whatsoever of the cover.  The main plot was that the remnants of an alien civilisation had been found, and there were spacecrafts with pre-programmed destinations. These destinations had not been deciphered, and any crew taking on an assignment had no idea where they'd be going, or even if they'd return alive, but crews were still lining up to go on a mission, be it for fame or fortune.  If I remember correctly, the story is divided between Earth and/or the location where the spacecrafts had been found, and one of the spacecrafts, which had been going for quite some time, and was nearing its point of no return.  This is about all I can remember, and most annoyingly I have no memory at all of how it ended.