Currently I have some zip files stored in the http root of my php/apache web server.  Currently I can access the files using this:  http://example.com/filename.zip   However, I want to "protect" the access to this files, and they should only be accessible using something like:  http://example.com/key/filename.zip   Could someone help me to create a rewrite rule to do this?  The key is a fixed string. It will be hardcoded in .htaccess rules.    When the user accesses the following URL:  http://example.com/key/filename.zip   He should be able to download the zip file.    When the user accesses the following URL:  http://example.com/filename.zip   He should not be able to download the zip file. He should receive an http error.    My code so far:  RewriteEngine on RewriteRule ^key/(\w+).zip $1.zip

This is a  about Apache's mod_rewrite.   Changing a request URL or redirecting users to a different URL than the one they originally requested is done using mod_rewrite. This includes such things as:   Changing HTTP to HTTPS (or the other way around) Changing a request to a page which no longer exist to a new replacement. Modifying a URL format (such as ?id=3433 to /id/3433 ) Presenting a different page based on the browser, based on the referrer, based on anything possible under the moon and sun. Anything you want to mess around with URL   Everything You Ever Wanted to Know about Mod_Rewrite Rules but Were Afraid to Ask!  How can I become an expert at writing mod_rewrite rules?   What is the fundamental format and structure of mod_rewrite rules? What form/flavor of regular expressions do I need to have a solid grasp of? What are the most common mistakes/pitfalls when writing rewrite rules? What is a good method for testing and verifying mod_rewrite rules? Are there SEO or performance implications of mod_rewrite rules I should be aware of? Are there common situations where mod_rewrite might seem like the right tool for the job but isn't? What are some common examples?   A place to test your rules  The  web site is a great place to play around with your rules and test them. It even shows the debug output so you can see what matched and what did not.


When I am trying to access catagory array after this code it gives me nullpointerexception. I am returning this array to other class. So it also produce nullpointerexception.    JsonObjectRequest req = new JsonObjectRequest(url, new JSONObject(),             new Response.Listener<JSONObject>() {                 @Override                 public void onResponse(JSONObject response) {                     // handle response                     try {                         JSONArray jarray=(JSONArray)response.get(item);                         catagory=new String[jarray.length()][2];                         //catagory_name=new String[jarray.length()];                         for(int i=0;i<jarray.length();i++){                             JSONObject jobj = (JSONObject) jarray                                     .get(i);                             catagory[i][1]=jobj.getString(sectionurl);                             catagory[i][0]=jobj.getString(name);                         }                     }                     catch (JSONException je){                      }                  }             }, new Response.ErrorListener() {         @Override         public void onErrorResponse(VolleyError error) {             // handle error         }     })   String str=catagory[0][0];//AT THIS LINE AN EXCEPTION IS THROWN

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I would like to completely wipe out the USB key and format it in fat32, but I am having troubles...   I needed Windows 7, so in Ubuntu 14.04 I installed WinUSB program and installed Windows iso image on my USB Key, then I installed Windows on one of my computers. Now I don't need this Windows boot USB key anymore and I would like to use this USB key for my data. I plugged in USB key into Ubuntu 14.04 and started GParted. Selected my USB key so /dev/sdb, right mouse click and selected Unmount and then Delete. Clicked on check box from toolbar to accept changes. I created new partition with fat32 file system and accepted the changes. Back to my file manager and to my surprise I can still!!! see Windows files on my USB key. Very strange. I am sure this is the only USB key in my computer. Other device /dev/sda is my hardisk. I Unplugged the USB Key and plug it back. In Nautilus file manager I can see like there are two USB volumes in my computer, very strange. It looks to me like on USB key is some hidden partition or something like that,that GParted can't see.   Please see print-screen I made in Ubuntu:    Any idea how to completely wipe out a USB Key? Thanks

I have a USB drive (SanDisk SDCZ40-016G) that mounts in a way I've never seen before. When inserted, two items appear in Places -> Computer:    "SanDisk Ultra Backup: 16GB" contains my data, and "CD Drive: U3 System" contains a Windows executable. The part with the Windows executable doesn't look useful to me so I'd like to remove it. I used GParted to delete the only partition listed on the device and then I created and formatted a new partition:    Strangely, the "CD Drive" containing the Windows executable was perfectly intact after this operation.  What's going on?


Can someone please explain what actually is a wave?I have read it is disturbance which transfers energy but am unable to get a intuitive feel of it. For example I cannot understand if it is a disturbance why we represent wave by the customary curve resembling sine graph. What does the curve actually represents?

I was watching an outtake of Prof. Brian Cox talking to a tv producer about "gravity waves".  Their discussion got a bit side-tracked, because the non-scientist didn't seem to understand what a wave "would look like", and also because there seemed to be some difficulties with the phrase "moving through", with Prof Cox saying that a wave doesn't move through space-time and then saying the ripples do.  I'm now not sure what moves when a speaker plays a sound; the air vibrates, but does "ripple outward"?  So, what is a wave?  Obviously, I'm really after a much simplified, probably broken, metaphor that allows me to visualise what a wave is. I understand that it will have flaws.  I forgot to include the youtube link, so here it is:


I am trying to make a code script for a timer but I cant get python to stop making a variable that I have made as: self.__time_seconds = 00 but when I tell it to print all I get is 0 as the printed output. So can I have your help to stop this please? Thanks!

Given: a = 1 b = 10 c = 100  How do I display a leading zero for all numbers with less than two digits? This is the output I'm expecting: 01 10 100


What is the difference between these two:  1- It seems water.    2- It seems to be water.

The baby seems happy/comfortable. The baby seems to be happy/comfortable.   Are these both correct? If both are correct, what are the differences between them?


Suppose that $K$ is an algebraic extension of a field $F$. Suppose that $R$ is a ring with $F\subseteq R\subseteq K$. I'm trying to prove that $R$ is a field. But I have no idea. Anyone can help me?

Let $E|F$ be an algebraic field extension and a ring $K$ such that $F\subseteq K\subseteq E$. It is true that $K$ is a field?


How can I format output from regex or return regex output in specific format. For example: I have a program test_program:5.4.3.2.11111 and I want to obtain only this value: 5.4.3.2.11111 If I use this function: import re  get_number = "test_program:5.4.3.2.11111" number = re.findall('\d+', get_number)  the output is: ['5', '4', '3', '2', '11111']  but I cannot pass it to another variable due to incorrect formatting. I've use something like this: import re  get_number = re.compile(r'\d.\d.\d.d.\d\d\d\d\d') number = get_number.search('test_program:5.4.3.2.11111') print(number.group())  and the output is in the correct format but if any number changes ex 5 will change to 10 or 11111 will change to 1111112, this will not work correctly. Is there any better solution to obtain number from string in proper format that will not be vurnable to changes?

What would be your preferred way to concatenate strings from a sequence such that between every two consecutive pairs a comma is added. That is, how do you map, for instance, ['a', 'b', 'c'] to 'a,b,c'? (The cases ['s'] and [] should be mapped to 's' and '', respectively.)  I usually end up using something like ''.join(map(lambda x: x+',',l))[:-1], but also feeling somewhat unsatisfied.


When i add a texture image to the background of the world, an unwanted purple color comes with. I don't know how to delete it (the purple color). I see it in the preview before adding the texture image from my folder. After adding the image, the preview is OK but if i render my 3d view i have always this purple color with my image. Somebody has a solution ?   (with blender 2.74)  Thanks for your help.  Matthieu  P.S : My light is not purple and it is not a duplicate. No files are missing and i don't use blender render but cycles render. I can see my image in the preview window. My problem is : when i assigne a texture the background is a mix with purple color and my texture. I don't want this purple color !   I think it's a bug. It works great with my older version of blender (2.66a).

I made a character, and its one of my first times texturing, and I saved my character into a new folder, and when I came back to the model ALL the textures were pink, I used to know what to do, but I stopped texturing, how do I bring my textures back?


I have created a view (userControl), with a data entry form. I also have a view model bound to it with all the logic. When the button is pressed it sends the data off to the server (I'm using a RelayCommand for the button) via a ButtonCommand() Method i created.  At the end of this method i want to do a:  this.Close()   but obviosly as "this" isn't referring to the view, it doesnt work.  Is there any way of closing the window without using Codebehind the view?  Thanks in advance

I'm trying to learn WPF and the MVVM problem, but have hit a snag. This question is similar but not quite the same ... I have a "Login" form written using the MVVM pattern. This form has a ViewModel which holds the Username and Password, which are bound to the view in the XAML using normal data bindings. It also has a "Login" command which is bound to the "Login" button on the form, agan using normal databinding. When the "Login" command fires, it invokes a function in the ViewModel which goes off and sends data over the network to log in. When this function completes, there are 2 actions:  The login was invalid - we just show a MessageBox and all is fine  The login was valid, we need to close the Login form and have it return true as its DialogResult...   The problem is, the ViewModel knows nothing about the actual view, so how can it close the view and tell it to return a particular DialogResult?? I could stick some code in the CodeBehind, and/or pass the View through to the ViewModel, but that seems like it would defeat the whole point of MVVM entirely...  Update In the end I just violated the "purity" of the MVVM pattern and had the View publish a Closed event, and expose a Close method. The ViewModel would then just call view.Close. The view is only known via an interface and wired up via an IOC container, so no testability or maintainability is lost. It seems rather silly that the accepted answer is at -5 votes! While I'm well aware of the good feelings that one gets by solving a problem while being "pure", Surely I'm not the only one that thinks that 200 lines of events, commands and behaviors just to avoid a one line method in the name of "patterns" and "purity" is a bit ridiculous....


My Select Table. I tried Pivot query to get my expected result but I was struct to generate the expected result.   WITH PersonOptions(ID,[Year], [Text], Value1, Value2) AS (               SELECT 'A',2000, 'X',10,2     UNION ALL SELECT 'A', 2001, 'X',21,1     UNION ALL SELECT 'A', 2000, 'Y',13,3     UNION ALL SELECT 'A', 2001, 'Y',2,3     UNION ALL SELECT 'B', 2000, 'X',0,2     UNION ALL SELECT 'B', 2001, 'X',5,1     UNION ALL SELECT 'B', 2000, 'Y',6,4     UNION ALL SELECT 'B', 2001, 'Y',9,5     UNION ALL SELECT 'C', 2000, 'X',3,5     UNION ALL SELECT 'C', 2001, 'X',2,8     UNION ALL SELECT 'C', 2000, 'Y',9,2     UNION ALL SELECT 'C', 2001, 'Y',8,3 ) select *  from PersonOptions  ID  Year    Text    Value1  Value2 A   2000    X        10       2 A   2001    X        21       1 A   2000    Y        13       3 A   2001    Y        2        3 B   2000    X        0        2 B   2001    X        5        1 B   2000    Y        6        4 B   2001    Y        9        5 C   2000    X        3        5 C   2001    X        2        8 C   2000    Y        9        2 C   2001    Y        8        3   Expected Output:                 Value1          Value2    ID  Text    2000    2001    2000    2001 A    X       10      2       21      1 A    Y       13      3       2       3 B    X        0      2       5       1 B    Y        6      4       9       5 C    X        3      5       2       8 C    Y        9      2       8       3

How can I pivot the following SELECT statement:           SELECT sc.CID,                 sc.CodeName     as OverviewText,                 scRAG.CodeName  as RAGStatusText             FROM StatusCode      sc LEFT OUTER JOIN ProjectOverview po               ON sc.CID          = po.ProjectOverviewCID              AND po.ProjectId    = 180 LEFT OUTER JOIN StatusCode      scRAG               ON po.RAGStatusCID = scRAG.CID           WHERE sc.SCID         = 18   Such statement yields the result set that follows:  CID OverviewText    RAGStatusText --- ------------    ------------- 153 Cost            Green 154 Requirements    Yellow 155 Schedule        NULL 156 Technical       NULL 157 Testing         NULL   But, I want it to return one single row with 10 values, as shown bellow:   ----------------------------------------------------------------------------------------------  | Cost | Green | Requirements | Yellow | Schedule | NULL | Technical | NULL | Testing | NULL |  ----------------------------------------------------------------------------------------------   Can I pivot on CID?


SQL:  Select top percent a,b,ROW_NUMBER() over(PARTITION BY a,b order by a,b) as rowsnumber from Students as s group by a,b   LINQ:  var students=from p in Students group p by new{p.a,p.b} into grp order by grp.Key.a,grp.Key.b .Select(s=>s.a,s.b).ToList();   I want to this SQL query convert to LINQ but not convert.

Lets say I have an array like this:  string [] Filelist = ...   I want to create an Linq result where each entry has it's position in the array like this:  var list = from f in Filelist     select new { Index = (something), Filename = f};   Index to be 0 for the 1st item, 1 for the 2nd, etc.  What should I use for the expression Index= ?


java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference. public class MainActivity extends AppCompatActivity {      Button yrebtn;     Button yrebtn1;     Button yrebtn2;       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);          yrebtn = (Button) findViewById(R.id.yrebtn);         yrebtn.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 Intent intent = new Intent(MainActivity.this, MainActivity1.class);                 startActivity(intent);             }         });          yrebtn1 = (Button) findViewById(R.id.yrebtn1);         yrebtn1.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 Intent intent = new Intent(MainActivity.this, MainActivity2.class);                 startActivity(intent);             }         });          yrebtn2 = (Button) findViewById(R.id.yrebtn2);         yrebtn2.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 Intent intent = new Intent(MainActivity.this, MainActivity3.class);                 startActivity(intent);             }         });     } }

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I have two groups I want to compare, however, I only have one data point in the first group compared to 450 data points in the second group.   Here's the story. I have a patient that has a mutation in one of his miRNA, and I'm trying to find if it affects the expression of the miRNA's target genes. So, I took one of the target genes and I compared its FPKM value (normalised expression) (group 1) to the genes that are expressed in patients that don't have this mutation (group 2).    I thought about doing a T-test, but obviously can't perform a T-test with what I have.  Do I need to generate "artificial" data in my first group in accordance with the elements from my second group?  Is there a package in R or a tool that could help me generate this data?  I tried searching for solutions but I only found options for re-sampling already existing data or creating new random data, which I do not want to do.  Thank you for your help!

For an ecology project, my lab group added vinegar to 4 tanks containing equal volumes of pond water, 1 control with no elodea (an aquatic plant) and 3 treatments with the same amount of elodea in each. The purpose of adding the vinegar was to reduce the pH. The hypothesis was that the tanks with elodea would go back to their normal pH quicker. This was indeed the case. We measured the pH of each tank daily for about two weeks. All the tanks eventually returned to their natural pH, but the length of time that this took was much shorter for the tanks with elodea.  When we told our professor about our experimental design, he said that there exists no statistical test that can be performed on the data to compare the control to the treatment. That because there was no replicate for the control (we only used one control tank) we cannot calculate variance and so we can't compare the sample means of the control and the treatment. So my question is, is this true? I definitely understand what he means. For example, if you took the height of one man and one woman, you can't draw conclusions about their respective populations. But we did 3 treatments, and the variance was small. It seems reasonable to assume that the variance would be similar in the control?  Update:  Thank you for the excellent answer. We got more water and elodea from the wetland and decided we would run the experiment again with smaller tanks but this time with 5 controls and 5 treatments. We were going to combine this with our original data but the starting pH of the tanks was different enough that it doesn't seem valid to consider the new experiment to be sampled from the same population as the original experiment.  We considered adding different amounts of elodea and trying to correlate speed of pH remediation (measured as time elapsed until pH returned to its original value) with amount of elodea, but we decided that wasn't necessary. Our objective is only to show that the elodea makes a positive difference, not to construct some kind of predictive model for exactly how the pH responds to differing amounts of elodea. It would be interesting to determine the optimal amount of elodea, but that's probably just the maximum amount that can survive. Trying to fit a regression curve to the data wouldn't be especially illuminating because of the various complicated changes that occur to the community when adding a large amount. The elodea dies, decomposes, new organisms start to dominate, and so on.


I've been learning about ARMA models in my time series course and noticed that for most ARMA($p,q$) models, $p$ and $q$ never really get larger than 3 or so. Is there a reason why models don't normally have larger values?  Thanks!

The function auto.arima in the forecast package of R is a powerful tool to identify the best ARIMA(p,d,q) model for a given data series. In the   of the function, they report the following:  auto.arima(y, d=NA, max.p=5, max.q=5, max.order=5, max.d=2, start.p=2, start.q=2, ...)   According to the above function it seems that, by default, auto.arima tries to find the best model among all the combination having:   p equal or lower than 5 q equal or lower than 5 d equal or lower than 2 order equal or lower to 5, i.e. p + q + d  ≤ 5.   However, why does the default code stops at these conditions? Is there any particular reason why p, q and d should be equal or lower than 5, 5 and 2 and their sum lower than 5?


After switching from PCs I was astonished to find I could only write emails in black, unless I wanted to take extra steps to change the black to another color, wasting time.  Is it so difficult to provide default color?  It's done for email "quote levels."

How can I change the default text color (black to dark grey) in Mail on Lion?


This is the density of a truncated Poisson:  $$P(X = x \mid X > 0) =   \frac{\lambda ^ x e^{- \lambda} }{x ! \left ( 1 - e^{- \lambda} \right )}$$  To show that it's member of the Exponential family I have to bring it in this form:   Exponential family:   $ f(x, \theta, \phi) = exp ( \frac{ x \theta - b(\theta}{ a(\phi)} + c(x, \phi ))  $  if I do this for the Poisson distribution I get: $$ \theta = log \lambda \\  \lambda = e^\theta \\ b(\theta)= e^\theta \\ a(\phi)=1 \\ c(x,\phi)= -log(x!)$$ I struggle now with this extra term $ \frac{1}{1-e^{-\lambda}}$ from the truncated Poisson. Where does it belong to?

In the theory of generalised linear models, you may use the exponential family to find the mean and variance of certain distributions. How would the mean and expectation of the zero-truncated Poisson model be calculated from the exponential family?  f(y; θ, φ) = exp  {[yθ − b(θ)]/φ + c(y, φ)}  f(y; λ) = (e^−λ*λ^y)/ y!(1 − e −λ)


Has somebody tried change the font size of top bar in Ubuntu 20.04? It looks like approach to modifying has been changed compare to Ubuntu 18.04. I've done recommendations from this . I've changed font-size in stage section, but looks like this is applied only to logon screen.  /* Global Values */ stage {   font-size: 9pt;   color: #3D3D3D; }   So, it looks correct on logon screen:    But nothing change in user session:    If somebody has ideas how to change font size of top bar in Ubuntu 20.04, then please share. Thanks!

I know this question is already asked but was for Ubuntu 18.10. I have found this  but when i tried to find /usr/share/gnome-shell/theme/gnome-shell.cssi didn't find anything. so this method is no longer working on the last version of ubuntu. I am wondering how to install stock Adwaita shell theme on Ubuntu 20.04 with Gnome 3.36? edit : i have found the solution by extracting /usr/share/gnome-shell/gnome-shell-theme.gresource using this  i got gnome-shell.css file which i moved to /usr/share/themes/AnyNameOfYourChoice/gnome-shell/  then changing shell theme using gnome-tweaks Thank you for your answer


If $x,y,z$ be positive real numbers and $xyz=1$, prove that  $$\frac{xy}{x^5+y^5+xy}+\frac{yz}{z^5+y^5+yz}+\frac{xz}{z^5+x^5+zx}\le 1$$  When does the equality hold?

Let $a, b$ and $c$ be posetive real numbers such that $abc=1$. I want to prove this inquality $$\sum_{cyc}\frac{ab}{a^5+b^5+ab}\le 1$$ I used AGM inequality but I didn't prove it.   Which should I use inequality? So thanks


I have a long and complex document that I want to render as a minimal outline only, without the body of the text. What is the best way to do this?  What I have tried so far is to save a version with titles only, and no other text. This does not work though. The outline gets caught off.  To try and solve the problem, I made a test file like this:  \documentclass{article}  \begin{document} \section{Foo} \subsection{bar} \subsection{bar} \subsection{bar} \section{Foo} \subsection{bar} \subsection{bar} \subsection{bar} [... eight more sections ... ] \end{document}   The output from this is a two page document, the first page of which is blank. On the second page, the outline appears, but it runs right to the margin until it gets cut off.  Adding a little bit of filler text to each section solves the problem. But without doing that, how can I get the output I would expect?  EDIT: I've edited this to emphasize the specific practical objective I am trying to accomplish, rather than the technical issue of empty sections which is covered .

I'm working on a large document in Emacs (23.2.1) org-mode (7.8.06) which I export to LaTeX. At present, the outline/structure of the document has been created, but not any of the content. The LaTeX version (which consists of \section, \subsection, \subsubsection and items mainly) has broken pagination, a blank page and text that runs off the page.  I shortened the document by moving \end{document} around to try to find the problem. In some cases, the document rendered correctly. This seems to be related to too many "section" types headings in LaTeX with no content.  To test this, I added  \usepackage[english]{babel} \usepackage{blindtext}   to my document and then inserted \blindtext "content" for most of the sections/subsections. The document now renders correctly.  The documentclass is article and the only package loaded is .  Are there any known issues with pdfLaTeX/pdfTeX where a document contains only/mainly section headings and not much, if any, content? The only relevant error message pdflatex generated was:  Overfull \vbox (333.44125pt too high) has occurred while \output is active [5] [6]   I'm using pdfTeX, Version 3.1415926-1.40.10 (TeX Live 2009/Debian).  An example can be found . The only required package is hyperref.


I just found out that I can see all of my passwords in Passwords and Keys program. That means any friend of mine can see my passwords if he/she uses my computer for some temporary use.  I know I can lock it and unlock it by entering password  How to I keep it locked until I enter password, and lock it again automatically after that one time use?  People should read the bold part above

I noticed that I have passwords in the Password/Encryption Keys program  . It appears that anybody who walked up to my computer could go look at all my passwords without needing a master password. Did I do something wrong or is this the default behavior? And if so, why?   and what if i lock my password is it get locked till i log out or for every time when i have 2to see password then i have to unlock keyrings . if then so how i protect my passwords from other . and why it is done so


Is there a specific bluetooth module for FTP? Or any bluetooth module can be used for FTP.. Because when i see the modules they are specified as being Serial. Will HC 06 be to  FTP? If not to what to use with STM32F4 to receive a file from android device via Bluetooth? (Q2) i am getting modules which say stereo audio transmission, can these be used

So far I have been doing projects with Arduino, RPi, ATtiny etc. But now I have project in mind where these things doesnt seem to suit. I need your help.  OK, now on the project:  I have a file on my android device (an image and a .ppt file). I want to transfer it to a SD card wirelessly (bluetooth or WiFi). I will be providing a USB port to access the data in SD card.  Now, I want to assemble/make all the electronics required around the SD card.   (Q1) Which one to choose Bluetooth or WiFi (my requirement is only short range, no internet involved) I want to know what Bluetooth module should I use (I have read that the HC06 is for SPP and I cannot transfer whole .ppt and do a FTP on that). (Q2) I don't want to use RPi or any ready made development board, I want to make my own minimum development board. Will this be possible using STM32F103 and do the Bluetooth transfer, if not which platform should I choose and how to make my own dev board?  (Q3) Is there a specific bluetooth module for FTP? Or any bluetooth module can be used for FTP.. Because when i see the modules they are specified as being Serial.  Please get me started on this. My question might be incomplete, please ask if any information required. (Please note: I had asked this question else where but I have tried to elaborate the question here, I have deleted the earlier question).


What is the implication if I don't fix a logistic regression that has complete or quasi separation? can I still read the marginal effects or are they not going to be valid?   My exercise is actually to just find out which independent variables are most predictive of Y.   I read some responses to complete/quasi-separation and I tried using logistf package for R but got this error message "NA/NaN/Inf in foreign function call logistf". why does this arises?

If you have a variable which perfectly separates zeroes and ones in target variable, R will yield the following "perfect or quasi perfect separation" warning message:  Warning message: glm.fit: fitted probabilities numerically 0 or 1 occurred    We still get the model but the coefficient estimates are inflated.   How do you deal with this in practice?


There is a recent update to Windows (KB4013429) that is incompatible with an application that we are using. I would like to prevent this update from installing. How can I achieve this ? EDIT: The tool suggested in the answer gives shows only five 'hideable' updates out of tens (or even hundreds).

We've upgraded some machines to Windows 10 and realized there were some updates which updated as required. However, I realized there was no option available to stop the download similar to that on Windows 7 and 8.1. The only way I could stop the download was to stop the Windows Update service.  My question is does anyone know of a way to stop auto updates or is stopping the service is the only solution?


In my textbook, the inequality $$|a+b|^r\leq 2^{r-1}(|a|^r+|b|^r)$$ for any real number $a$, $b$ and $r\geq 1$, is called "elementary". It is not elementary to me, how do you prove it? I see that the inequality reduces to the triangle inequality if $r=1$ so I am more interested in $r>1$.

I have a small question that I think is very basic but I am unsure how to tackle since my background in computing inequalities is embarrassingly weak -   I would like to show that, for a real number $p \geq 1$ and complex numbers $\alpha, \beta$, I have \begin{equation} |\alpha + \beta|^p \leq 2^{p-1}(|\alpha|^p + |\beta|^p) \end{equation}  I thought it would be best to rewrite this as  \begin{equation} \left|\frac{\alpha + \beta}{2}\right|^p \leq \frac{|\alpha|^p + |\beta|^p}{2} \end{equation}  but then I am unsure what to do next - is this a sensible start anyways ? Any help would be great !  (P.S. this is not a homework question - I am currently trying to brush up my knowledge of $L^p$ spaces, and this inequality came up as a statement. I thought it might be worthwhile to  make sure I can fill in the gaps to improve my skills in computing inequalities.)


There are 100 numbered objects from 1 to 100. We extract 3 of these objects one after the other without reinsertion. Calculate the probability P(a<b<c)  The number of arrangements of three objects is 50∗49∗48 but the first number a must be a < 99 while b must be a < b < 100 What's the next step?

There are 50 numbered objects from 1 to 50. We extract 3 of these objects one after the other without reinsertion. Calculate the probability P(a<b<c)  Given 3 objects, they can be ordered in $3!$ different ways. Of all these ways only 1 satisfies a<b<c so the probability should be:  $P(a<b<c) = \frac{1}{3!} = \frac{1}{6}$  Is it solved in the right way?


At work we have a creative group which produces videos that our sales team uses for powerpoint decks, client presentations, etc.  The creative group is mac-based so they produce quicktime files which are unplayable on a Windows PC unless you install Quicktime (which we don't, by default).  Quicktime files also don't work very well when you try to embed them into a powerpoint presentation.  We're tired of dealing with video compatibility issues so we want to tell the creative group to produce videos in a more compatible format, but I'm not sure what that should be.  I don't really want to tell them to produce windows media video files because that isn't the most compatible format outside Windows.  Is there a generic format that Windows 7 can play without the need for any additional software?  I was thinking h264 or something similar, but had a tough time finding a definitive list of what Windows supports.  What I'm really asking is what would be the best video codec and container that's compatible with Windows 7 out of the box and also compatible with the largest number of other systems?

Apologies if this question has been asked many times before... but I can't find a duplicate.  I'm helping a colleague prepare a Powerpoint presentation. We have no control over the computer that it will be delivered from (we simply hand the PPT file over beforehand). I am making an assumption that it will be running Windows 7 & Powerpoint 2010, as we are.  As I understand it, Powerpoint will embed and play quite a wide range of video formats, if the relevant codecs are installed on the PC. Because we don't control the PC we need to assume that it has nothing installed that doesn't come automatically with Windows or Powerpoint - but which formats are these?  To put it another way: What video format can we embed in Powerpoint and be confident that it will play on any Windows 7 PC?  Thanks.


I have a for loop and I'm looking for a way to skip few iterations whenever that condition is satisfied. How can I do it in python?  Here's an example when condition is satisfied for the first time,  for i in range(0, 200000):     # (when 0 % 300 it meets this criteria)      if (i % 300) == 0:                      # whenever this condition is met skip 4 iterations forward         # now skip 4 iterations --- > (0, 1, 2, 3)      # now continue from 4th iteration until the condition is met again          Similarly, this should happens whenever if condition is satisfied.

I have a loop going, but there is the possibility for exceptions to be raised inside the loop. This of course would stop my program all together. To prevent that I catch the exceptions and handle them. But then the rest of the iteration runs even though an exception occurred. Is there a keyword to use in my except: clause to just skip the rest of the current iteration?


I am trying to prove that this equality is correct. \begin{equation} \lim_{n \to \infty}\left(1+\frac{1}{n}\right)^n =\lim_{n \to\infty} \left(\frac{1}{0!}+\frac{1}{1!}+\frac{1}{2!}+\dots + \frac{1}{n!}\right) \end{equation} I know that left and right hand side is equal to $e$, but as mathematician I would like to see is this two definition of $e$ is equal. My idea is to try avoid using hard calculus tools, and try two show that two sequence has the same limit.

How to prove that the following definitions of $e^x$ are equivalent, with as simple tools as possible and without any knowledge of $e$ or logarithms ?  $$\sum_{n=0}^{\infty} \frac{x^n}{n!}=\lim_{n\to\infty}\left(1+\frac{x}{n}\right)^n$$  Also preferably, prove that this is $a^x$ for some real number $a>0$.


So I was asked a question by someone that "if everything in the universe is expanding, then the lens we use to look at stellar objects is expanding as well, meaning we shouldn't be able to tell the difference at all".  I replied with "local forces overpower expanding forces, hence the lens doesn't change size at all, whereas at cosmic scales, local forces are too weak so things move apart. In other words, the lens doesn't change size, the question is false, the universe is expanding"  He replied with "the lens DOES change size, just at a different rate than stellar objects are moving apart from each other, hence we know the universe is expanding"  So, what's the actual answer?  I also looked into a similar question:   But here, OP stated in his question (after receiving an answer) that:     The answer seems to be (from Marek in the previous question) that the gravitational force is so much weaker than the other forces that large (macro) objects move apart, but small (micro) objects stay together. However, this simple explanation seems to imply that expansion of space is a 'force' that can be overcome by a greater one. That doesn't sound right to me.   This is exactly what I mean to ask. Is the expansion of space a "force" that can be overcome, or not? Unfortunately, nobody has addressed that part of the question in that thread, hence I'm asking here.

I have looked at other questions on this site (e.g. "why does space expansion affect matter") but can't find the answer I am looking for.  So here is my question: One often hears talk of space expanding when we talk about the speed of galaxies relative to ours. Why, if space is expanding, does matter not also expand? If a circle is drawn on balloon (2d plane), and the balloon expands, then the circle also expands. If matter is an object with 3 spatial dimensions, then when those 3 dimensions expand, so should the object.  If that was the case, we wouldn't see the universe as expanding at all, because we would be expanding (spatially) with it.  I have a few potential answers for this, which raise their own problems:   Fundamental particles are 'point sized' objects. They cannot expand because they do not have spatial dimension to begin with. The problem with this is that while the particles would not expand, the space between them would, leading to a point where the 3 non-gravity forces would no longer hold matter together due to distance Fundamental particles are curled up in additional dimensions a la string theory. These dimensions are not expanding. Same problems as 1, with the added problem of being a bit unsatisfying. The answer seems to be (from Marek in the previous question) that the gravitational force is so much weaker than the other forces that large (macro) objects move apart, but small (micro) objects stay together. However, this simple explanation seems to imply that expansion of space is a 'force' that can be overcome by a greater one. That doesn't sound right to me.


Each single post and archive page for my custom post type is giving me a 404 -- both /thing and /thing/my-post . Here is my setup in functions.php . Is there something else I'm supposed to do, such as permalink rewriting? WP should be using single.php without requiring a single-{post_type}.php, unless I want to customize it for this CPT, correct?   // Register Custom Post Type function custom_post_type_thing() {      $labels = array(         'name'                  => _x( 'Things', 'Post Type General Name', 'text_domain' ),         'singular_name'         => _x( 'Thing', 'Post Type Singular Name', 'text_domain' ),         'menu_name'             => __( 'Things', 'text_domain' ),         'name_admin_bar'        => __( 'Things', 'text_domain' ),         'archives'              => __( 'Thing Archives', 'text_domain' ),         'parent_item_colon'     => __( 'Parent Thing:', 'text_domain' ),         'all_items'             => __( 'All Things', 'text_domain' ),         'add_new_item'          => __( 'Add New Thing', 'text_domain' ),         'add_new'               => __( 'Add New', 'text_domain' ),         'new_item'              => __( 'New Thing', 'text_domain' ),         'edit_item'             => __( 'Edit Thing', 'text_domain' ),         'update_item'           => __( 'Update Thing', 'text_domain' ),         'view_item'             => __( 'View Thing', 'text_domain' ),         'search_items'          => __( 'Search Thing', 'text_domain' ),         'not_found'             => __( 'Not found', 'text_domain' ),         'not_found_in_trash'    => __( 'Not found in Trash', 'text_domain' ),         'featured_image'        => __( 'Featured Image', 'text_domain' ),         'set_featured_image'    => __( 'Set featured image', 'text_domain' ),         'remove_featured_image' => __( 'Remove featured image', 'text_domain' ),         'use_featured_image'    => __( 'Use as featured image', 'text_domain' ),         'insert_into_item'      => __( 'Insert into Thing', 'text_domain' ),         'uploaded_to_this_item' => __( 'Uploaded to this Thing', 'text_domain' ),         'items_list'            => __( 'Things list', 'text_domain' ),         'items_list_navigation' => __( 'Things list navigation', 'text_domain' ),         'filter_items_list'     => __( 'Filter things list', 'text_domain' ),     );     $args = array(         'label'                 => __( 'Things', 'text_domain' ),         'description'           => __( 'Things', 'text_domain' ),         'labels'                => $labels,         'supports'              => array( 'title', 'editor', 'excerpt', 'author', 'thumbnail', 'comments', 'custom-fields', 'post-formats', ),         'taxonomies'            => array( 'category', 'post_tag' ),         'hierarchical'          => false,         'public'                => true,         'show_ui'               => true,         'show_in_menu'          => true,         'menu_position'         => 5,         'show_in_admin_bar'     => true,         'show_in_nav_menus'     => true,         'can_export'            => true,         'has_archive'           => true,         'exclude_from_search'   => false,         'publicly_queryable'    => true,         'capability_type'       => 'page',     );     register_post_type( 'thing', $args ); } add_action( 'init', 'custom_post_type_thing', 0 );

I'm developing a Custom Post Type plugin, which works fine in dev. Now that I've moved it to production, I'm getting a 404 when I try to display the template for the CPT.   So, two questions:  1- Is there some mechanism to determine the path WP took to get through the hierarchy?  2- Why wouldn't it just give me the single or index page?  I've dumped $wp_query and a stacktrace at the end of the 404. Here's part of what I found:  [query] => Array     (         [page] =>          [pagename] => refletters/proximity     )  [request] => SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND (wp_posts.ID = '0') AND wp_posts.post_type = 'page'  ORDER BY wp_posts.post_date DESC  [posts] => Array     (     )  [queried_object] =>  [queried_object_id] => 0   And the stack trace:  2013-04-27 22:16:41 - 24.52.197.40 - TRACE - index.php - 404.php[39] -      wordpress/wp-content/themes/notoriousconsultant/404.php[39] - aaLog->logtrace     wordpress/wp-includes/template-loader.php[50] - include     wordpress/wp-blog-header.php[16] - require_once     wordpress/index.php[17] - require   Thanks for your help.


I want to encrypt some small amount of data using ECDH for use by myself later, but I don't want to generate an ephemeral keypair like in ECIES, due to time and space constraints.  Would it be safe to use my existing EC keypair to encrypt data "for myself"?  In this case I don't need to store any key material with the ciphertext, which is nice.  But is it secure? Alternatively I could just hash my private key and use that as the symmetric key. Would that be more or less secure?    The encryption goes as follows. Let $P$ be my public point on the curve secp256k1 and let $P=[d]G$ hold with $d$ being my private key. I encrypt a message $m$ as follows:   I perform an ECDH agreement with my own public key, i.e. compute $S=[d]P$ I hash the common point with SHA256 to get the key $K=H(S)$ I generate a 16 byte IV uniformly at random using a CSPRNG: $IV\xleftarrow{\$}\{0,1\}^{128}$ I encrypt the message using AES-256-CBC as $c=E_{K,IV}(m)$ I return $(IV,c)$, knowing that I can re-derive $K$ using only my key-pair

I am using ECIES (Cryptobox as poncho pointed out) for public key encryption with ECC between Alice and Bob with secret/public keys $(a,A)$ and $(b,B)$ respectively. So Alice encrypts to Bob with  $$ Encrypt(aB,Message) $$  Additionally I would like to encrypt some of Alice's data such that only she can decrypt it. Is it safe to use ECIES to compute a shared secret from Alice's secret and public key as in  $$ Encrypt(aA,Message) $$  I know I could randomly generate a public key, but then I would have to store this key somewhere which I would like to avoid.


If Co-variance (X, Y) = 0, does this necessarily mean that X and Y are independent?  I have read in previous posts that Co-variance equal to 0 implies that (1) X and Y are independent AND (2) X and Y could be independent, but are not necessarily so.  These two interpretations, however, are obviously contradictory.

Any hard-working student is a counterexample to "all students are lazy".  What are some simple counterexamples to "if random variables $X$ and $Y$ are uncorrelated then they are independent"?


I have couple of longer waypoints names that I would like to put in two rows with center formatting but I just don't know how? I tried to put  tag but it doesn't help...  For example I have the waypoint with name 'one two three five six seven' and I want to make it like this:   one two  three five six seven

How can I apply Multiline label option in the label property?  Name field contains a lengthy name. I want to wrap it.   My QGIS version is 1.8.


When I'm working on some remote host via SSH, I often need to upload or download files.  With my current setup, I need to switch to another terminal and conjure up rsync or sftp, which can be a pain if the target host isn't registered in DNS (need to copy+paste IP address) or if I'm working in a directory a few levels down (need to re-type the whole path).  Is there a command-line tool that combines SSH and SFTP?  Ideally, it would start a remote shell like normal SSH does but at the press of some key combination, it would switch to an SFTP prompt allowing me to up- download files from the directory the shell is currently in.

If I'm logged in to a system via SSH, is there a way to copy a file back to my local system without firing up another terminal or screen session and doing scp or something similar or without doing SSH from the remote system back to the local system?


I'm an Indian citizen planning to travel from Jeddah (Saudi Arabia) to Calicut (India) by car. I want to know whether I can cross the border at  with my car.

I was planning a trip by car when I found something a bit weird in :if you try to cross from Lahore to India, it tells that you have to 6457 km detour.  Is it possible to cross this border driving? If not, is there another way to cross without having to make more than 6000 km?


Now I get this error:  WARNING:root:could not open file '/etc/apt/sources.list'   I would somehow like to get my original file back, plus some good instructions about how to install R that won't corrupt it.    ok - copied old version. Looks like the version after some program copied in the sources for the R package. Now get error:  sudo apt-get update E: Malformed entry 50 in list file /etc/apt/sources.list (absolute Suite Component) E: The list of sources could not be read.   Here is the file - what I think are lines  49 - 51. (Got an error about too many links when I tried to include the whole file)  # deb-src http://security.ubuntu.com/ubuntu bionic-security universe deb https://cloud.r-project.org/bin/linux/ubuntu bionic-cran35/ apt update sudo # deb-src https://cloud.r-project.org/bin/linux/ubuntu bionic-cran35/ sudo apt update   (The first and third line start with #)    Ok - now tried gedit with line numbers on as you suggested. Just deleted line 50. Now get update is running. Don't know if R will actually install but this solves the issue I posted here. How do I accept your answer? And thank you very much for all your help.

There are now errors when updating and I cannot install most software due to a corrupted  /etc/apt/sources.list   file. Is there a copy I can download to replace it?  The file would be for Ubuntu 12.04 (Final Beta) in the United States.


Consider this standard MWE:  \documentclass[11pt]{beamer} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc} \usetheme{default} \begin{document}  \begin{frame}  \begin{itemize}     \item Equation 1 here:           \begin{equation}         Pr( Y= n)  = \frac{e^{-7}\times 7^n}{n!}          \end{equation}      \item Equation 2 here:          \begin{equation}          Pr( Y= n)  = \dfrac{e^{-7}\times 7^n}{n!}         \end{equation}  \end{itemize}  \end{frame} \end{document}   It produces:    I want to achieve this:    I can do it manually adding \vspace{-1.05cm} before both equations.  Instead, I would like this to be done automatically.  Notice I want to preserve the equation number, so using inline $ equation $ at the \item level is not enough (plus it would need manual centering, depending on equation length.   Is there a way to achieve what I want?   Related posts that haven't helped me are  and .

I think the following sample says it all.  I need to get the item bullet in the right place on the same line as the equation, and have this followed by an normal equation number.  Someone asked the same question but the answers all give one of the undesired results exhibited below.  This problem crops up a lot if you are writing lists of conditions and some need a text Preamble while some are just equations.  Thanks for any help anyone can offer.  \documentclass{article} \begin{document}  \begin{itemize} \item This item looks fine in terms of both number and bullet because the bullet sensibly appears on a line with some text on it, preceeding an equation like \begin{equation} 2+2=4, \end{equation} but if there is no text in the item there is no way to get it right, for example \item \begin{equation} 2+2=4; \end{equation} The bullet is on the wrong line. \item $\displaystyle 2+2=4;$ \\ No equation number. \begin{equation} \bullet \quad 2+2=4. \end{equation} Bullet in wrong position. \end{itemize} \end{document}


There appears to be another question about conveyor belt on this site; however, that question just asks for a correct expression. I actually have asked much more than that question. I provided an additional formula that I derived and asked whether it is correct. This is not included in that question.  A conveyor belt moves at constant velocity $v$. At $t=0$, sand starts to be dropped onto the belt at the rate $\mu \text{kg/s}$. The mass of sand on the belt is, therefore, $m=\mu t$. Please ignore resistive forces in this question.  NB Sand has zero velocity in the direction of the belt's motion before it is dropped onto the belt. Sand does NOT have any kinetic energy before it reaches the belt, and when it reaches the belt, it moves with the belt, with velocity $v$: they are "attached" to each other.  The belt continues to move with constant velocity $v$ throughout.  Now, the problem I am trying to solve is:     What is the additional power needed to keep the speed of conveyor belt constant, after sand starts to drop?   I tried to work it out in two ways, but got different results.  Method 1: $$ P=\frac{dE}{dt}=\frac{d (\frac{1}{2} mv^2)}{dt}=\frac{d (\frac{1}{2} \mu v^2 t)}{dt}=\frac{1}{2} \mu v^2. $$  Method 2: $$ P=\frac{dE}{dt}=\frac{Fdx}{dt}=Fv=v\frac{dp}{dt}=v\frac{d(mv)}{dt}= v^2\frac{dm}{dt}+mv\frac{dv}{dt}=\mu v^2. $$  I have no idea which is right: intuitively, $\frac{1}{2} mv^2$ is the total kinetic energy gained by the sand. Dividing this by $t$ gives the average power $\frac{1}{2} \mu v^2$. So this seems to be the correct value.  However, the mark scheme says the answer is $\mu v^2$. My second method also seems more reliable, in that it just uses the definition of momentum and force.  I doubt that the formula $E=(1/2) mv^2$ may not be correct in this situation: $$ dE=Fdx=vdp=\frac{1}{2m}2p dp=\frac{1}{2m}d(p^2), $$ which is not the same as $E=(1/2) mv^2$, because $m$ is not constant. However, the expression $\frac{1}{2m}d(p^2)$ looks very strange and counterintuitive. (Why $m$ is not differentiated?!)   Which of the above are correct and which are wrong?  Can anyone explain intuitively where the factor of $1/2$ comes from?  Why the statement "intuitively, $\frac{1}{2} mv^2$ is the total kinetic energy gained by the sand. Dividing this by $t$ gives the average power $\frac{1}{2} \mu v^2$" is incorrect?

Say we are given a conveyor belt with sand falling onto it at rate $\Omega$. I am trying to find the power it takes for the belt to operate if it goes forward with constant velocity $v$, but using two different approaches I get two different answers.  The first way, I say that in one second, $\Omega$ amount of sand falls onto the belt, thus every second $\frac 1 2 \Omega v^2$ is required to continue moving the belt forward (simply by looking at kinetic energy difference) and $P=\frac 1 2 \Omega v^2$  The second way, I saw that $F=\frac {d(mv)} {dt}$, thus $F=\Omega v$. Finally, $P=Fv$ so $P=\Omega v^2$.  So which one is it: $P=\Omega v^2$ or $P=\frac {1} {2} \Omega v^2$, and where did I make an incorrect assumption in my two methods?


I have an issue related to what server to approximate for the following scenario (a real situation):  I have a server where will be stored some videos that can be accessed through a web application running on this server. There will be about 100 (concurrent) users that will use it (generally through tablet or phones, but PC's will be also included).  Can you give me some thoughts on building the hardware configuration for this server? The OS running on it will be Linux.  Thanks in advance.    EDIT I:  The web server that I use is Apache HTTP, but it's very likely it will act as proxy for a Java server (installed on this machine of course).  Other applications that will run on this server will be:    an application for authentication  an application for administration.   This server will run also continually (24/7).

This is a  about  Related:      I have a question regarding capacity planning. Can the Server Fault community please help with the following:   What kind of server do I need to handle some number of users? How many users can a server with some specifications handle? Will some server configuration be fast enough for my use case? I'm building a social networking site: what kind of hardware do I need? How much bandwidth do I need for some project? How much bandwidth will some number of users use in some application?


Suppose we have two statements:  $$P_1= \forall x(\;P(x) \vee Q(x)\;)$$  $$P_2= \forall xP(x) \vee ∀xQ(x)$$  I would like to ask about correct implication between those statements. I know the difference between those statements but I have problem to choose correct implication.

Context  I'm having trouble understanding the limited situations in which qualifiers can be distributed.  I am given that the rules are:  $$\forall x\left[P(x)\land Q(x)\right]\equiv\forall xP(x) \land\forall xQ(x) \tag{1}$$ $$\exists x\left[P(x)\lor Q(x)\right]\equiv\exists xP(x) \lor\exists xQ(x) \tag{2}$$  $$\forall x\left[P(x)\lor Q(x)\right]\not\equiv\forall xP(x) \lor\forall xQ(x) \tag{3}$$ $$\exists x\left[P(x)\land Q(x)\right]\not\equiv\exists xP(x) \land\exists xQ(x) \tag{4}$$    Questions   What are examples of $P(x)$ and $Q(x)$ that illustrate when these statements are true? How can I show these statements always hold using proofs? Why can't "$\forall x$" be distributed in example 3 or "$\exists x$" in example 4?


My facebook is grabbing the wrong image.  I try to adding this open graph image in my head.  <meta property="og:image" content="<?= $_GET['image'] ?>" />   and  <meta property="og:image" content="<?php echo $image; ?>"/>   but the content image path is not shown.  It became this   <meta property="og:image" content="" />   I want it to be like this. If the article A have image a_name.jpg, the meta will be <meta property="og:image" content="/images/a_name.jpg"/>  If the article B have image b_name.jpg, the meta will be <meta property="og:image" content="/images/b_name.jpg"/>

On our  we have a Facebook "Like it" button, which works fine, but if someone "likes" us, Facebook shows an ugly picture.  As we want Facebook to link to the same content on every page, also on pages which are not driven by a node but by a view, this makes Drupal node based meta tags and open graph useless, is it?  How can we tell Facebook what to show about our website?


I saw this in the lock screen of Windows, wondering where this is. Any clues?

Windows 10 has an extensive collection of lock screen photos, many of which have  here on Travel.SE.  Is there a website which lists the location of all of these photos? I imagine Microsoft has purchased an official license, so they should have a record about the photographer and the place where the photo was taken.


A word for the unexpected reaction of laughing in a situation of complete hopelessness or laughing with sad undertones

What word or phrase could be used to describe a joke about something serious or bad? It isn't meant as humor in the typical sense, but as sort of a brave, different flavor of humor between two friends. Something that isnt actually funny, and could be really bad, but I choose to joke about it to dismiss fear. Between two people that accept life's events, and understand being morbid isn't going to change the matter at hand. For example:  "So we found out more about that chest problem my sister got checked for."  "So how long does she have?"


How to prove that  $$ \tan^{-1}(x)+\tan^{-1}(\dfrac{1}{x})=\pi/2? $$    I have tried to use  $$ \tan^{-1}(x)+\cot^{-1}(x)=\pi/2. $$ But I do not know how to go further.

Verify the identity: $\tan^{-1} x + \tan^{-1} (1/x) = \frac\pi 2, x > 0$  $$\alpha= \tan^{-1} x$$  $$\beta = \tan^{-1} (1/x)$$  $$\tan \alpha = x$$  $$\tan \beta = 1/x$$  $$\tan^{-1}[\tan(\alpha + \beta)]$$  $$\tan^{-1}\left [{\tan\alpha + \tan\beta\over 1 - \tan\alpha \tan\beta} \right]$$  $$\tan^{-1}\left[ {x + 1/x\over 1- x/x }\right]$$  $$\tan^{-1}\left[{x + (1/x)\over 0} \right]$$  I can't find out what I'm doing wrong..


What is the injective hull of $\mathbb Z_n$?  I know that in case $n=p$ is prime, the injective hull would be isomorphic to $\mathbb Z_{p^∞}$, but in general case, I have no idea. Can anyone be of some help to me? Thanks in advance!

In the category of $\mathbb{Z}$-modules, what is the injective envelope of $\mathbb{Z}/n\mathbb{Z}$?   I was hoping to find a divisible group containing $\mathbb{Z}/n\mathbb{Z}$ such that it is also an essential extension. We already know that $\mathbb{Z}/n\mathbb{Z} \rightarrowtail \prod_{i \in \lbrace 1,\ldots,n \rbrace}(\mathbb{Q}/\mathbb{Z})_i  $. But is this an essential extension? I can't prove or disprove it.  Guessing by the 'size' of it ($\prod_{i \in \lbrace 1,\ldots,n \rbrace}(\mathbb{Q}/\mathbb{Z})_i   $), i don't think that it is the right answer.  Also, is there an algorithm sort of thing for finding injective envelope for modules over arbitrary rings.


Example of this are:  "Nanana na na nana... I am happy, nana na na" "Lala la la la la. We are the gnomes. lala la la la"  Is there a word for this? I thought it was a onomatopoeia, but I don't think they are, or at least they belong to a different subclass.

I've been searching for the word, which is used for describing parts of lyrics, where the singer sings for example the whole refrain only using words of syllables without any meaning. Maybe you could help? (here's one song with that type of refrain: )


I am using glmrob with family = "binomial" in a regression model with a dichotomous dependent variable. How do I test whether the logistic model assumptions are met? What are the assumptions I should be testing for and what methods/packages do you suggest I can make use of in R to do the same?

I am looking for guidelines on how to interpret residual plots of glm models.  Especially poisson, negative binomial, binomial models.  What can we expect from these plots when the models are "correct"? (for example, we expect the variance to grow as the predicted value increases, for when dealing with a Poisson model)  I know the answers depend on the models.  Any references (or general points to consider) will be helpful/appreciated.


The situation is as follows: there are 6 people in the team, we work together and come up to an answer/question. They all have legit profiles - they are not sock puppets. However, sometimes we do upvote a post if we consider that it might help us individually or as a team. Question: might this be considered a voting anomaly? There is a small paragraph in :  We now perform a more detailed statistical analysis on voting patterns. Any voting patterns that are too far outside the statistical norm will be nullified.  Does it applies to my situation?

Almost every time a colleague of mine asks a question, we have discussed this problem beforehand. Also, we sometimes meta-discuss the question for stackoverflow (why did I get the "this might be subjective" warning, is this understandable enough, etc). This is less so with answers, but I could believe for some groups this works the same. For now I'll stick to questions, but you could s/question/answer if you like. The resulting question is almost always  Interesting for me, and a problem I don't know the answer to. I probably would favorite it According to me a valid and good question (as we talked about it beforehand) I would probably want to upvote it.  Now I believe to read that "ring voting" is a thing, and I tried to find some questions about this, but didn't find many. I did find and read this blogpost from 2008:  . It reads to me that upvoting 'fraud' is more commonplace then downvoting and it might seem anomalous that I would upvote almost all questions from one user. If all colleagues would do this to their team, you'd get some mediocre questions getting a lot of votes, and some users getting a lot of attention, points etc from that. If you would -as seems to be done -, sort the amount of upvotes for my colleague, you'd get me being 'anomalous' in front of the crowd. On the other hand, as explained above, I do want to upvote almost all stuff some of my colleagues put on here for (I believe) the right reasons: they are questions I consider good and interesting. It's just that I know of all their questions (as they tell me about them), which obviously isn't the case for a random user. So what is the deal?  When is upvoting content from one user frowned upon? Would my usecase be in danger of being a (what I consider 'false') positive for the fraud-detection? (and would you agree with that or not) How to prevent this false positive (if you agree with me it is one, otherwise this is a moot question) -> As noted in the comments: I'm not looking for tricks, so an answer could be "don't vote for your colleagues". I agree that there should be no to 'tricks' around that could be used for real fraud of course


I have a script which pulls something out of my shell history and saves it to a file, but if there is a newline in the history entry it gets returned to me with a literal \n instead of the newline character.  I'd like to replace the \n with a newline before saving it to the file.  I'm on OS X, and figured the problem might be the BSD-based sed that ships with OS X (that always seems to be the problem when sed isn't behaving!)  so I tried with gsed, and what was failing with sed worked on the first try with gsed:  history -1 | awk '{$1=""; print}' | gsed -e 's/^[[:space:]]*//' -e s/'\\n'/"\n"/   But if at all possible I'd like something that'll work with the default utilities (whether sed or something else) on both Linux or OS X, since I can't count on gsed being installed on OS X, and since GNU sed is the normal sed for Linux there is obviously no need for gsed.

I'm so confused with GNU sed, POSIX sed, and BSD sed's myriad of options.  How do I replace literal \n with the newline character using these three sed types?


For a week now I cannot add comments, or use the blue "view more comments" or flag questions. How to fix this? A week ago when travelling I had the captcha option happen on all my comments and answers. That stopped when I got home. I had thought it was because I was too active on stackexchange, but when I used a laptop (or the app on this tablet) there are no restrictions at all. Same on each SE site, regardless of reputation (e.g 1000) Tried logging out and in again. Using Safari 9.0 (the latest permissible) on ipad 2 with iOS 9.3.5 Tried using Dolphin Browser, didn't work there either. (Cannot use chrome, firefox etc on this old iOS). Tried clearing safari cache and history. When I hit "Add a Comment" or "flag" it just jumps to the top of the question. I can still answer questions, but with none of the text formatting options or no picture adding available. Cannot up- or down- vote. When I am logged out, or on sites where I am not a member, e.g Aviation, I can use the blue show further comments button! Not sure if this is a problem with my account, or change of SE software.

Which browsers are officially supported by Stack Exchange?  Also, what else is needed in order to use every feature of the site?


If a moving balloon (let's say it's a blimp system with some rotors for movement) is connected to the ground by a cable that describes a catenary curve, how can we model the tension being applied on the blimp by the cable?     This force has a vertical component that will be related to the mass of the cable and a horizontal component with the opposite direction of the movement of the blimp. Is there any model for this kind of behavior?

I'm looking for an equation to find the tension on the ends of a cable suspended between two poles (one higher than the other) with no load but the cable itself.    I determined that the tension would be different on each end, that the shape of the suspended cable would be a  truncated at one end, and that the following would be the variables necessary in the equation:   cable weight cable length vertical distance between ends horizontal distance between ends   Some links that could be helpful:


I am writing for a friend of mine that is experiencing this issue. He has a few accounts here at SE and logged in through yahoo.com for the account in question.  That email address for some reason is not working anymore, and he cannot access his accounts on the Yahoo side or the SE side.  How can one change one's email address if one cannot access his own accounts?

How do I log in if my OpenID is not available, or maybe even no longer exists? Can I restore my lost account, or do I need to start over?  See also:


I'm stuck with this problem: Assume Alice and Bob are using RSA to communicate each other. Given Bob's public key $(217,7)$, Alice send the ciphertext $c=53$ to Bob through RSA encryption. Now, Eve can read the ciphertext $c$, how can Eve decrypt the ciphertext and read plaintext $m$?

Assume Alice and Bob are using RSA to create a common session key and Cindy is listening, attempting to obtain the session key.  Alice and Bob each have their public- and private-key pairs ($\left[pub_{A}, pri_{A}\right]$ for Alice and $\left[pub_{B}, pri_{B}\right]$ for Bob) and Alice, Bob, and Cindy all know everyone else's public key.   Alice generates a random $n_{A}$ and sends out $En_{pub_{B}}\left(n_{A}\right)$ ($n_{A}$ encrypted with Bob's public key). Bob generates a random $n_{B}$ and sends out $En_{pub_{A}}\left(n_{B},n_{A}\right)$ and sets the session key to $n_{A}\oplus n_{B}$. Alice sends out $En_{pri_{A}}\left(n_{B}\right)$ and sets the session key to $n_{A}\oplus n_{B}$.   My thinking is, Cindy decrypts message 3 with Alice's public key to obtain $n_{B}$.  Now Cindy has a plaintext, ciphertext pair and the key that decrypts the ciphertext.  My question is, is it possible with this information for Cindy to find $pri_{A}$ in order to decrypt message 2 and find $n_{A}$?


I was wondering if there is a way to display a custom pop-over on the hover of a standard field in Salesforce lightning! I know with the overlay library one can display it on custom button clicks or hovers.  To be more specific, i wanted to display a custom pop-over on a field in the highlight panel. Any inputs on this is appreciated.  Thanks in advance.

I wanted to show a custom pop over on a standard field in lightning. I know pop overs can be display using the overlay library. However, I am not sure how can i achieve this on a standard field.  It would be even better if it's possible to show it on a highlight panel. Any help is appreciated.


I'm trying to add a footnote using \footnote{foobar}. But it won't show up in the footer of the document. I believe this is due to the fact that I manually changed the sizes of the layout of the document. Can anyone suggest a fix without changing the geometry of the layout. Here is the preamble to my .tex code  \documentclass[11pt]{article} %\pagestyle{empty}  \usepackage{amsmath} \usepackage{graphicx} \usepackage{textcomp}  \usepackage[parfill]{parskip} \usepackage{booktabs} \usepackage{fancyhdr} \pagestyle{plain}  %the following code I think messes with footer width/height of the document. \textheight=8.5in \textwidth=6.5in \topmargin=-1in \oddsidemargin=0in  \begin{document} \begin{tabular}{c c c c c } \toprule Course No. & Course title & Credits & Grade & Institution \\ \midrule Math 644    & Real Variables & 5    & A & LLM \footnote{foobar} \\ Math 456    & Algebra I                 & 3 & A & LLM \\ \midrule         & Total Transfer Credits     &\fbox{18} &   &   \\ \bottomrule   \end{tabular} \end{document}   Thanks in advance for all your help.

I would like to have footnotes in tables, but the \footnote command does not work inside a table environment.  Googling one finds that this is , at least in the UK.  That link contains a list of solutions to the problem, but since the author of the FAQ does not believe that this is good style, no comparison is made between the different methods.  I am sure that there are good typographical reasons why in most situations it is undesirable to have footnotes in tables (although I have never come across them), however I have recently felt the need to do just this in a paper I am currently writing.  Therefore I'd like to ask two questions:   What are the arguments against footnotes in tables? If one really must go against the advice in 1., which method (whether considered in the  or not) would you recommend?   Thanks in advance.  Added  In response to ShreevatsaR's comment: I do not much care for where the text of the footnote appears.  I do however insist on the footnote marks being attached to the relevant entries in the table, so that I can avoid having to reference "the second entry in the eighth line of the table", etc...


I'm trying to implement 2FA using Twilio Authy using Laravel 5.8. I'm looking to add the functionality where user can scan the QR Code or manually enter the code to add an account to Authy app on their phone. I followed  and able to generate QR Code using online QR generator, but I'm not able to find any documentation on how to generate a 16 digit alphanumeric secret key to manually enter in Authy app instead of scanning QR Code. How can I accomplish that?

How can I generate a (pseudo)random alpha-numeric string, something like: 'd79jd8c' in PHP?


I have 1.4 million addresses that I need to batch geocode. I can't find a free service to do so. Does anyone know of something out there that I can use? Oh, the service needs to be were I can upload a file in a .txt file formate, not a copy and paste. Copy and paste services crash the 661 mb size file.

For a one-time project, I need to geocode a few thousand addresses.  In the past I've used various online resources for this kind of thing (e.g., Google Maps API), but the addresses I'm working with have to be kept confidential - which means no sending it over the Internet, unless there's some iron-clad guarantee of privacy.  What other options do I have?


I have just started using LaTeX and have made a practice document where I am trying to add a reference list and it is not appearing in the PDF viewer.  Here is the simple code I have   \documentclass{article} \usepackage{apacite}  \begin{document}  \section{introduction} Hello there  \nocite{*} \bibliographystyle{apacite}   \bibliography{conttimeReferences}  \end{document}   Would be grateful for any tips - also keep in mind I am a beginner and my understanding is very limited.

I'm having some problems with my bibliography in Texmaker. My code is:  \documentclass[11pt, a4paper]{article} \usepackage{graphicx} \usepackage{amsmath} \usepackage{natbib} \usepackage[utf8]{inputenc}     \usepackage{natbib} \usepackage[usenames,dvipsnames]{xcolor} \usepackage[left=2cm,right=2cm,top=2cm,bottom=2cm]{geometry} \begin{document}  ....  \cite{Johnson} \bibliographystyle{plain} \bibliography{mybib}  \end{document}   I also created a new file (File > New) that I saved as mybib.bib:  @Article{Johnson, author = {Edgar G. Johnson and Alfred O. Nier}, title = {Angular Aberrations in Sector Shaped Electromagnetic Lenses for Focusing Beams of  Charged Particles}, journal = {Physical Review}, year = {1953}, volume = {91}, number = {1}, }  @phdthesis{Zoran, author = {Zoran Racic}, title = {\'Etude et essais du spectromÃ¨tre Ã  plasma {DYMIO} de la  mission {MARS 96}}, publisher = {UniversitÃ© Pierre et Marie Curie}, year = {1996} }   When I compile my .tex file, I only have a [?] appearing.  Could you tell me what my mistake is?


I was declared Undesirable in South Africa in 2018 because i overstayed, I want to travel to Malawi but the flights are connecting in South Africa, will they allow me to transit through South Africa to Malawi?

I received an undesirable status for overstaying a SA visa while hospitalized for injuries sustained in Lesotho. I had to cross into SA from Lesotho. Now I am banned entry into SA until Feb 2016 and though I have submitted a waiver request to remove the undesirable status, I hear from some the waiver request may take 4-5 months or even take longer than the time of banishment.  I have a pre-paid safari planned in October in which I need to fly through Johannesburg to get to Botswana. The Jburg border control requires tourists to pass through SA immigration even when simply changing planes.  1) Will SA grant me "transit" access if I don't leave the airport?  2) Will SA allow me to spend a night in the airport as the layover is 12 hours>  Thanks for passing on any info.


Stretch your imagination a bit and imagine an almost empty universe with nothing in it but a very, very large asteroid (or an asteroid in our universe but in an almost empty patch so it's not affected too much by other celestial bodies).  I travel to this asteroid and I use some powerful drill and dig a tunnel to the center of mass of this asteroid.  Far away in another empty patch of the universe an atomic clock ticks exactly one second. Consider this the "proper" time interval.  The equation to calculate gravitational time dilation under the effect of a non-rotating object is  $$ \Delta t_{ 2 }= \Delta t_{ 1 } \sqrt { 1-\frac { 2Gm }{ rc^{ 2 } }  }   = \Delta t_{ 1 }  \sqrt { 1-\frac { r_{ s } }{ r }  } $$  where $r_s$ is the Schwarzschild radius, $r$ is my distance from the center of the center of mass, $\Delta t_2$ is the time interval experienced by the observer and $\Delta t_1$ is the proper time interval.  In order to try to solve the time dilation using this equation while I sit exactly on the center of mass I have to divide by 0 because my distance from the center is 0.  Since that would be mathematically undefined, how long has passed relative to an observer at the center of a non-rotating and not very massive object?  I've searched for other questions but they use other equations, consider black holes, talk about the Earth, or have been closed due to poor wording by the OP. My curiosity is what this can tell me about how one would experience time at the center of an asteroid.

I would like to know what happens with time dilation (relative to surface) at earth's center .  There is a way to calculate it?  Is time going faster at center of earth?   I've made other questions about this matter and the answers refers to:  $\Delta\Phi$ (difference in Newtonian gravitational potential between the locations) as directly related, but I think those equation can't be applied to this because were derived for the vecinity of a mass but not inside it.  Any clues? Thanks


I have following query: SELECT p.product_name, SUM(o.quantity) no_of_product_sale   2  FROM Order_Address_Quantity o   3  JOIN Product p ON p.product_code = o.product_id   4  GROUP BY p.product_name;  which results in: PRODUCT_NAME                   NO_OF_PRODUCT_SALE ------------------------------ ------------------ Coffee                                         10 Noodles                                         4 Oil                                             8 Rice                                            5 Dishwasher                                      3 Biscuits                                        2  6 rows selected.  How can I show the product with maximum no_of_product_sale? In other SQLs it can be done by adding LIMIT = 1 clause.

Is there a way to make an Oracle query behave like it contains a MySQL limit clause? In MySQL, I can do this: select *  from sometable order by name limit 20,10  to get the 21st to the 30th rows (skip the first 20, give the next 10). The rows are selected after the order by, so it really starts on the 20th name alphabetically. In Oracle, the only thing people mention is the rownum pseudo-column, but it is evaluated before order by, which means this: select *  from sometable where rownum <= 10 order by name  will return a random set of ten rows ordered by name, which is not usually what I want. It also doesn't allow for specifying an offset.


$(document).ready(function(){  $(".add-item-popup").click(function(){   var form = "<input type='text' class='add-item-inp' />";   $.alert(form);  });   $(".add-item-inp").change(function(){   alert($(this).val());  }); });   <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/jquery-confirm/3.3.0/jquery-confirm.min.css">     Add       I have an input field in a popup and I'm trying to grab the value of input when it's changed. But I'm not able to grab the value of that input field that I added through jquery inside a popup. Please help

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


The cryptography algorithm I designed is a completely new algorithm and has no similarity to other existing algorithms. But because I am an ordinary person, I have no facilities and the ability to introduce this algorithm except through my website .   Given the fact that there are no absolutes, this algorithm may also have weaknesses that would affect its validity. Therefore, the website was created solely for testing this algorithm, so that the algorithm will be publicly released if approved by experts in the field. But despite repeated attempts and correspondence with reputable technology websites, nobody was willing to help me. Please guide me and help inform this.

I came up with a truly new method of applying modulo-2-addition encryption function in stream ciphers which is inspired by a mechanism used to prove a mathematical theorem. How can I determine whether my method is cryptographically correct and considerable? If so, how can I officially submit or formally register it in my name? And finally, can I make money thorough this method just by selling it to an encryption company or organization?  EDIT  Hi everyone, thanks for all answers and comments. It seems quite heartening.  I know that modulo 2 operation is equivalent to XOR (exclusive OR operation in Boolean Algebra) gate in electronics. As you all know, the overriding issue concerning the security of stream ciphers is how to generate truly random key streams, and actually my newly-inspired method mainly deals with this issue. I mean this method can produce or generate random key streams in an entirely new way for either stream or block ciphers. I finally decided to publish my workings on this topic very soon for gaining cryptographic credits rather than just making money.


<?php // Silence is golden.   The folder is ../wp-content/index.php  Why have this file. What's the purpose?  I suppose it's in order to avoid invalid visit.  But why?

WordPress itself, in the wp-content folder, includes an empty PHP file which looks like this.  <?php // Silence is golden. ?>   Should plugins include an empty file like this as well to stop folks view viewing the contents of a directory?  What about additional folders in themes -- like an includes directory?


I created an LWC component with lightning-radio-group and added it to the Lightning App, it only shows which value is selected by the user. As I selected value and move the back and forth on the tabs of the same application and when I came back to the LWC component tab, it shows the same selected value. The tab should refresh. I am also attaching a video with this issue. Video Link:-  CODE HTML <template>     <lightning-card title="Radio Group in LWC">
             <lightning-radio-group label="Account Type"                                      name="radioButtonGroup"                                      onchange={handleChange}                                      options={options}                                     value={selectedValue}                                     type="radio"></lightning-radio-group>

                 Selected Value: {selectedValue}

      </lightning-card> </template>  JS import { LightningElement, wire, track} from 'lwc'; import { getPicklistValues } from 'lightning/uiObjectInfoApi'; import { getObjectInfo } from 'lightning/uiObjectInfoApi'; import ACCOUNT_OBJECT from '@salesforce/schema/Account'; import Type_FIELD from '@salesforce/schema/Account.Type';  export default class RadioButtonsInLWC extends LightningElement {     @track selectedValue;     @track options = [];      // object info using wire service     @wire(getObjectInfo, { objectApiName: ACCOUNT_OBJECT })     objectInfo;      // Getting Account Type Picklist values using wire service     @wire(getPicklistValues, { recordTypeId: '$objectInfo.data.defaultRecordTypeId', fieldApiName: Type_FIELD})     typePicklistValues({error, data}) {         if(data) {             let optionsValues = [];             for(let i = 0; i < data.values.length; i++) {                 optionsValues.push({                     label: data.values[i].label,                     value: data.values[i].value                 })             }             this.options = optionsValues;             window.console.log('optionsValues ===> '+JSON.stringify(optionsValues));         }         else if(error) {             window.console.log('error ===> '+JSON.stringify(error));         }     }      // handle the selected value     handleChange(event) {         this.selectedValue = event.detail.value;     } }

I have a couple custom lightning pages and apps, both overriding default record views and standalone pages (just straight nav to from the sidebar). It seems that every time we go from 'tab' to 'tab' it just hides the content rather than destroying it. When you navigate back to the tab, it does recreate the components, so you end up with 2 of everything sitting out there.  I noticed this b/c we have a component that registers to an app event. And every time you navigate away from and back to the page, the handler is registered +1. So going back and forth a few times you pretty quickly have 10s of the same handlers firing for each app event.  Anyone seen this? Thoughts?  If you create a Lightning App, add this component, and assign it to lightning menu you can see what I mean. Just go the app click home and then click back:  Comp:  <aura:component implements="force:appHostable,flexipage:availableForAllPageTypes">     <aura:handler event="c:BoringAppEvent" action="{!c.test}"/>     hi     <ui:button press="{!c.onClick}" >App Event</ui:button> </aura:component>   controller:  ({     test : function(component, event, helper) {         console.log('Clicked');     },     onClick : function(cmp, evt){          var notEvt = $A.get('e.c:BoringAppEvent');          notEvt.fire();     } })   Renderer  ({     unrender: function(){         this.superUnrender();         console.log('unrender');         debugger;     } })   BoringAppEvent.evt  <aura:event type="APPLICATION" description="Event template" />


$$\int_{-2}^{2} \frac{x^2}{(1+5^x)}dx$$ I tried taking the substitution of $$1+5^x = u$$ in hope i will get product of two functions which can be integrated by parts but it turns out to be a very complicated function. Is it possible to integrate it using some property of definite integral?

$$\int^2_{-2}\frac{x^2}{1+5^x}$$  How do I start to integrate this?  I know the basics and tried substituting $5^x$ by $u$ where by changing the base of logarithm I get $\frac{\ln(u)}{\ln 5}=x$, but I got stuck.  Any hints would suffice preferably in the original question and not after my substitution.  (And also using the basic definite integrals property.)  Now I know only basic integration, that is restricted to high school, so would prefer answer in terms of that level.


I am using coding below for slides, but an error of Undefined control sequence. \end{frame} appears and also \smashoperator[r] not works properly in slides, Need kind suggestions for this issue. \begin{frame}     \begin{propa}\label{proposition1}         Let $p(\cdot)\in \mathcal{P}(\mathbb{R}^{n}), q\in(0,\infty]$ and $\lambda\in(0,\infty]$. If $\alpha(\cdot)\in L^{\infty}(\mathbb{R}^{n})\cap \mathcal{P}^{log}_{0}(\mathbb{R}^{n})\cap \mathcal{P}^{log}_{\infty}(\mathbb{R}^{n})$. then         \begin{align*}         \norm{f}_{M\dot{K}^{\alpha(\cdot),q(\cdot)}_{p(\cdot),\lambda} (\mathbb{R}^n)} \approx \max          \biggl\{          &\sup_{\smash[b]{\substack{L\leqslant0,\\ L\in\mathbb{Z}}}}          2^{-L\lambda} \biggl(\,\smashoperator[r]{\sum_{k=-\infty}^{L}}         \,\norm{2^{k\alpha(0)}f\chi_{k}}^{q(0)}_{L^{p(\cdot)}} \biggr)^{\!\!1/q(0)},\\         &\sup_{\smash[b]{\substack{L>0,\\ L\in\mathbb{Z}}}}          \biggl[          2^{-L\lambda} \biggl(\,\smashoperator[r]{\sum_{k=-\infty}^{-1}}         \,\norm{2^{k\alpha(0)}f\chi_{k}}^{q(0)}_{L^{p(\cdot)}} \biggr)^{\!\!1/q(0)}\\         &\qquad +         2^{-L\lambda} \biggl(\sum_{k=0}^{L}         \,\norm{2^{k\alpha(\infty)}f\chi_{k}}^{q(\infty)}_{L^{p(\cdot)}} \biggr)^{\!\!1/q(\infty)}\,         \biggr]          \biggr\}.         \end{align*}     \end{propa} \end{frame}

\begin{multline*} \displaystyle \left \| f  \right \|_{M\dot{K}^{\alpha(\cdot),q}_{p(\cdot), \lambda}(\mathbb{R}^{n})} \approx \max \left\{ \sup_{L\leqslant0,L\in  \mathbb{Z}}2^{-L\lambda}\left ( \sum_{k=-\infty}^{L}2^{k\alpha(0)q}\left \|  f\chi_{k} \right \|^{q}_{L^{p(\cdot)}} \right )^{1/q},\\\sup_{L>0,L\in \mathbb{Z}}\left[ 2^{-L\lambda}\left ( \sum_{k=-\infty}^{-1}2^{k\alpha(0)q} \left \| f\chi_{k} \right \|^{q}_{L^{p(\cdot)}} \right )^{1/q}\\ +2^{-L\lambda}\left ( \sum_{k=0}^{L}2^{k\alpha(\infty)q}\left \|  f\chi_{k} \right \|^{q}_{L^{p(\cdot)}} \right )^{1/q}\right] \right\}  \end{multline*}


Am planning to buy PS4 from Hong Kong and about to return India, do they charge custom duty tax for that once i arrive in india?  Please reply

I am planning to travel to India (COK airport, Kerala) from United States. I want to take my laptop as well as my tablet (iPad). Am I allowed to take both in my backpack with my documents related my work. I think I am allowed to take only one computer as per the rule. Will the customs consider my iPad as a computer?  What all I can take?   One of my friends took 2 laptops (1 work and 1 personal) and had trouble at the airport.  Also I am planning to take some wristwatches (7 of them, each avg price is 45 $). I read in a website that I can take stuff up to max 35000 INR. Is that true? In that case, how will I manage my stuff?


<?php $user_id = 23; $abc_username = "orange apple";  "WHERE u.user_type = 2 AND u.status = 1 AND (u.sponsor_id = '".$user_id."' OR u.placement = '".$abc_username."' )"   Syntax error on '".$abc_username."' because '".(only accept integer, not accept string)."'; May you tell me what is the correct syntax to put php variable that holding string value?   I have tried \'".$abc_username."\' as the solution from this page   but still syntax error.

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening?


I know what my symbol or character looks like, but I don't know what the command is or which math alphabet it came from. How do I go about finding this out?


I have a question regarding marriage. I am not able to find the right Stack Exchange site. Please help.  I am 18. I have several points, like I get angry on small things and many more. I will list them. I need advice: Should I marry or live single?

Stuff like polls, recommendations based on subjective constraints, puzzles, webcomics etc. do not belong on the serious main SE sites, where professionals should be considered at work and having just a few spare minutes ("code's compiling") to answer questions, so they should not be distracted by such things. However, I'd also like to have a home for these things still using the SE engine. For the reason I mentioned before, this needs to be a separate place though. Let's call it four.[sitename-here].com.


I'm having a hard time finding documentation on the various 'in the box' patterns like  %logger   %level   %timestamp     There is of course  but I'm not sure that's the full list of options.  I also know that it's possible to MDC parameters out of the app to the logger, but that involves a code change which is a different beast than a config change.  Is there a %machineName option, or machineIP option?  The issue is that we have all our servers in the web farm log into the same database log, and we're now thinking that a disproportionate number of messages are coming from one machine.

I am using Log4Net with the AdoNetAppender to log messages from a simple systray application into a SQL Server 2005 database.  I want to log the machine name along with the log message because this application will be running on multiple machines and I need to know on which one the message originated.  But, I cannot find a way to expose this information via the log4net.Layout.PatternLayout that I am using with the appender.  Is there a way to log the machine name via log4net in this manner?


In iOS 9.0.1, I can no longer use the control center play/pause button to force play Youtube in the background while open in Safari. I can see the name of the video, but if i click "play" the button flashes white, but doesn't change to "pause" and the video doesn't play. Why is this happening and is there any way to fix it?

I remember that once upon a time I was able to start a song on the YouTube app (or Jasmine), then go and do other things on the phone.  That doesn't seem possible anymore with iOS 10.  Am I missing something simple?


today i installed ubuntu 14.04LTS on windows 7 then in ubuntu , win 7 partition didnt appear. it shows whole drive  3.1gb used and 147. gb free how to recover win 7 partition and uninstall ubuntu and win 7 back

I have absolutely no experience with Linux, and I desperately need to get my computer back up and running again with Windows.  How do I remove Ubuntu and reinstall Windows?    Editor's note: many of the answers are about removing Ubuntu from dual-boot but keeping Windows (which is a bit complicated), while other answers are about removing Ubuntu from single-boot (which is easy: basically just format the disk while installing Windows). The question as written is ambiguous between dual-boot or single-boot.


just noticed this, the hot questions on main page do not seem to be stable at all. clicked "refresh" on a main or meta page and they instantly/constantly change. understand that it would constantly change over time but dont expect it to change one page refresh to the next, that seems like a bug.

I've recently noticed that the hot questions list is now different almost every time I look at it. It used to be static - I.e. I could browse around for half an hour and the items on it would be minimally changed.  Was the algorithm changed? In what way?


I have a coastal line layer ( us-medium-shoreline from  ), which is loaded into a project with On-The-Fly reprojection ( WGS 84 / World Mercator CRS with +proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs) and  I'd like to create a 500m buffer around this shoreline with the ultimate goal of intersecting the shoreline with inland polygons.  I'm expecting a polygon with the coastal line as its center, but I keep getting a circular region as resulting layer (with empty attributes table). Clearly I'm missing something as a GIS newbie.

I  have had no luck getting the buffer tool to accept anything but degrees as units of measure.  I have found lots of stuff saying the layer needs to be reprojected and saved but it hasn't worked at all for me.   Is there a way I could create a buffer without using ftools or at least force the units to meters somehow?  As a workaround I converted meters to degrees (lat) and used that but the final product needs to be as close to reality as possible.  Things I've tried:   setting every unit option I could find to meters (where possible). setting everything to NAD83/Maryland (data is for Washington, DC) and saving it as such (as layers in ESRI shape files). reimporting the reprojected layers setting relevant layers to Google Mercator   The was tried followed by creating a buffer. Many were tried in combination. QGIS 1.7.3 Slackware64 current (qgis from SBo-13.37 repo, tried on multilib and plain 64it with same results)


The best answer on one of my questions is in the comment section. I don't want to bother the commenter by asking for a formal answer so that I can give it the love (upvote and accept) that it deserves. Is it acceptable to answer my own question with a summary of the comment, maybe providing additional insight? (I did this , just now).

I'm trying to go through and provide answers to every unanswered question (search "closed:0 answers:0"), somewhat following the spirit that was blogged about at  .  However, I'm finding this much more difficult than it needs to be, as many of the questions have already been answered without the use of an "answer" - but instead, in the form of a comment by either the OP or another poster. I wouldn't mind reading through and skipping these, as long as there was some appropriate action I could take to at least assist with preventing these questions from being seen again from the same query - either by myself or another SO member.  Is there such an appropriate action?  Should we vote to close?  If so, using what reason? Even if I vote to close, what are the chances that 4 other users will also view the question and also vote to close?  (i.e., will my individual vote even do any good?  Is there any report to show recent close votes, so that others may also review and contribute supporting close votes?) Should we post some sort of an answer - even just something to the effect of "this was already answered by the OP's own comment to his answer (above)"? Would something like this be appropriate to flag for moderator attention, and let the moderators deal with it?  (Or would this be considered too trivial?) Should we rename the question title to something standard that can be used in a search exclusion?  (Maybe "SOLVED:"?)  Basically, how can I help to denote questions as "This question is no longer in active search of an answer - though better answers may still be appreciated."? I've already reviewed , which was closed as a duplicate of  - but this requires effort on part of a user who may very likely no longer be active. Otherwise, is there something I should be doing to improve my search to filter out these types of questions? I've run across this many times, so I don't consider it to be a rare issue.  However, the last question like this I just ran across, prompting this question, was .  In this case, the question was self-answered by the OP in the form of a comment, this question is the OP's only question, the OP has no other visible activity on SO, and the OP hasn't been seen on SO since he registered and posted the question 5 months ago. Another one I just ran across is .  However, here the "answer" comment was posted by a reputable and recently active SO member.  Should I leave a comment directed at him, asking him to re-post his comment as an answer, or should I post my own answer echoing his comment?  (Or something else?) Yet another is .  Interestingly, the OP actually self-edited the question to include the "SOLVED:" prefix on to the question, instead of posting his resolving comment as an answer (and ideally accepting it) as he was asked to do by another comment.  This brings up another good idea - is there a "standard" we should use to rename the titles on these "resolved but unanswered" posts that could be used as a search exclusion?  (Also added to the above list.)


I'm stucking with this problem for days. f is a function from $\mathbb{R}$ to $\mathbb{R}$ satisfies: $$f(yf(x) + y) = xy + f(y) \qquad \forall x, y \in \mathbb{R}$$ Prove $f$ is surjective, and hence find all the functions satisfy this equation. I think fixing a $x$ and $y$ as a constant and study the function might be a good idea, but so far I've been only playing with $x=1,0$ and $y=1,0,$ and they didn't seem to help in proving surjectivity. Any help is appreciated. Thanks! (Proving injectivity is easy)

Question     Let the function $f:\mathbb R\to\mathbb R$,and such   $$f(xf(y)+x)=xy+f(x)$$      Find all $f(x)$   Let $x=1,y=1$,then $$f(f(1)+1)=1+f(1)$$ let $f(1)=t$,then $$f(t+1)=1+t$$  So I guess $$f(x)=x$$ is such it, and I found $f(x)=-x$ is also such it?   Can you help?  I found this simaler problem：(BMO 1997, 2000) $$f(xf(x)+f(y))=y+(f(x))^2,f:R\to R$$ this answer $f(x)=x$ or $f(x)=-x$,  the full solution can see