htmlentities() not working when using with data from a table

I'm trying to print data from a table that contains a special character such as é. I've used the function htmlentities() hoping it solves the problem, but instead of solving the problem, the data wouldn't appear at all.  For example:  I'm supposed to print this:      "Lightroom 3 pour les Phototographes du Numérique"   However, the character é appears as �. Thus using the fuction htmlentities() should logically solve the problem. Yet whilst using it with a string that contains the character é nothing prints but an empty space. Using the function on a string that contains no special character works fine.     "Lightroom 3 pour les Phototographes du Numerique"   prints as it is, while      "Lightroom 3 pour les Phototographes du Numérique"   prints as     " "   My databse and all the tables are UTF-8 encoded, as well as my html document.


How to add the logs to a crontab with time stamp

In crontab, I scheduled a daily backup script. Now when the cron executes the script the status are logged to a log file as shown below.  0 0 * * * /home/backup.sh > /home/groupz/db-backup/fbackup.log 2>&1     Now, when the cron executes a script the contents of the log get renewed everytime. So, I want the contents to be added to the same file with time stamp of the executed time and below the contents of each time along with the existing contents. How can I do this.


Can I say "it was a pleasure meeting you" after a phone call?

Is it possible to say "it was a pleasure meeting you" after the phone call? Or should we better say ""it was a pleasure to talk to you"?


What is the icon between settings and lock-screen in Gnome3?

I can't figure out what the icon between my settings and lock-screen icon in Gnome3 is supposed to do.  It has two states, locked and unlocked, but it's not the lock screen. When I click it, it toggles its status.


Is the minimum GPA required for Graduate school a cut-off criteria or a general guideline?

I am a senior year undergrad student from a prestigious institute in India. I intend to pursue a PhD after graduating. While researching universities, I stumbled upon the fact that many of the top schools have a minimum GPA requirement. For example UCSD has 3.4/4 as its minimum requirement.   My GPA is 7.2 on a scale of 10. It is quite above average in my school, but it translates to a 2.9 on a scale of 4 which looks pretty bad. DOes this mean that my application is likely to be rejected outright?   Also, I heard that most universities don't consider converted scores (by WES, for example) in a good light. I have research experience in my undergraduate years to offset the GPA. I really hope that the universities have a look at that.   Should I not apply to schools with such a requirement?


If $\{x\}$ denotes the fractional part of $x$ and for $n\in \mathbb{N}$ we define the set $A_{n}=\left\{k \in \mathbb{N}: \{\frac{n}{k}\}  \geq \frac{1}{2} \right\}$. Then how can I try to calculate the sum: $ S_{n}=\sum_{k \in A_{n}} \varphi(k)$ where $\varphi$ is the Euler's totient function. I've tried calculating the sum by hand for integers $1\leq n\leq 10$ and noticed that $S_{n} = n^{2}$ for these, but other than this, I have not found any other patterns.


Referencing to a theorem using \cite and memoir

I am citing a book, and I would like to reference a specific theorem within that book. Usually, I would use something like      \cite[Theorem~4]{Reference}   which would have produced something like [1, Theorem 4] as an output. However I am using the memoir document class, and when I try to do that I get the following error:      ! Argument of \@citex has an extra }.   Is there any way to circumvent this without too much pain?  (Removing the [Theorem~4] part from the code works just fine.)


Prove that if $[F(\alpha):F]$ is odd then $F(\alpha)=F(\alpha^2)$.  My justification for this question is as follows;  Suppose $F(\alpha^2)\subsetneq F(\alpha)$, we have $F \subsetneq F(\alpha^2) \subsetneq F(\alpha)$.  As $[F(\alpha):F]=[F(\alpha):F(\alpha^2)][F(\alpha^2):F]$ and $[F(\alpha):F(\alpha^2)]=2$ we would be end up with the case that $[F(\alpha):F]$ is a multiple of 2 i.e., even which contradicts given condition of $[F(\alpha):F]$ being odd.   So, $F(\alpha^2) =F(\alpha)$.  After doing this, i have seen for a solution on some webpage where he/she used criterion of minimal polynomial.  Please let me know Is my justification clear or there are any gaps in between?


50km for someone who has no experience cycling long distance

I'm considering cycling along a sand dune which is 50km. The bike path is mainly flat. The longest I've riden on a bike is probably less than 1 hour. I do occasionally cycle within the city but it's just short distances. I was wondering if 50km will be too much for me? And will an e-bike help?  Jessie


Python extract after and before certain conditions

I'm looking to extract only what appears after '/g' and before the '+' or '?'  urls = ["https://www.google.com/es/g/Dmitry+Kharchenko?searchterm=isometrico",        "https://www.google.com/es/g/Irina+Strelnikova?searchterm=isom%C3%A9trico",        "https://www.google.com/es/g/ParabolStudio?searchterm=auto"]  for i in urls:     print(re.findall(r'g/(.*)[\+|\??]', i))   ['Dmitry+Kharchenko'] ['Irina+Strelnikova'] ['ParabolStudio']  Desired result:  'Dmitry' 'Irina' 'ParabolStudio'


concerning the effects of temperature and density on the speed of sound

here is my relatively broad question: how does the temperature and density of a medium effect the speed at which sound travels through it?   Now I shall elaborate:  it is my understanding that there is some sort of ratio between these two factors that determine the speed of sound in the medium.   from this, I assume that sound travels faster in objects that have a higher temperature (due to atoms/molecules having more energy and hence being more inclined to transfer energy more quickly in order to assume its former energy state and become more stable) and a higher density (which I can only assume to be because the particles  are closer together and so somehow travel faster because of this, however, couldn't one also say that the opposite is true because there is less obstruction to block the waves? this is a point of confusion for me, help would be appreciated).  is there some sort of relationship or equation that relates the three factors and are there any other factors that determine the speed of sound in an object (eg. elastic properties of the medium)?  is there a value for this ratio that maximises the speed of sound (ie. some sort of linear constant) and is the relationship between speed and temperature and speed and density linear? if not what is it?  finally, with regard to the equations V=λ/T V=fλ and T=1/f where T=period, is the speed (velocity) of sound also dependent on the frequency and wavelength of the sound waves, or is it the other way round in which the frequency and wavelength are dependant on the velocity of the wave which is in turn dependant on other factors such as temperature and density? of course if the latter is true, what decides how the given product of frequency and wavelength is factored into individual components?


Background movie clip does not show up in render

I did some tracking in Adobe AE and then ran a script to import it into Blender. I set a background image in the N menu, but I can only see it in the viewport, I can't see it when I render. Any help would be appreciated. Blender 2.79b, cycles render.


How can I prove formally that the projective plane is a Hausdorff space?

I want to prove the Hausdorff property of the projective space with this definition: the sphere $S^n$ with the antipodal points identified. It's seems easy, but I can't prove formally with this definition. I take neighborhoods of the points $p$, $q$ in $S^n/\sim $, with $p\neq q$. In $S^n$ we will have four points $p$, $q$, $-p$, $-q$, with 4 disjoints neighborhoods by the Hausdorff property of $\mathbb R^{n+1}$. I don't know how to prove with rigour why when we pass to the quotient we will have two disjoints neighborhoods of $p$ and $q$.  Thanks


As of time of writing it's quite common to see headlines about so-and-so who have tested positive for Covid-19, e.g.   However, these articles don't usually say how reliable the testing is. I couldn't find any recent information on it via Google, either (there are some results, e.g. , but they are old).  How accurate are the tests? What are the odds that Sophie Trudeau's results are a false positive, or that Justin Trudeau's negative result is a false negative?


i've been searching for the perfect machine for blender.. the highest rated production level machine,that break up mentioned on blender site.  I cant go so much in to technical depth of pc components. in some parts something is lacking and something is up to the mark . its difficult to chose. So my question is very simple.  If i buy Apple MacBook Pro – MJLT2 would that be the perfect machine for blender in all aspects.Would i be able to do every ting from sculpting to rendering pretty easily on that machine? Specs for the mac book are below.  • 2.5GHz Quad-core Intel Core i7, Turbo Boost up to 3.7GHz • 16GB DDR3 RAM - 1600 • 512GB SSD Flash Storage • Intel Iris Pro Graphics + AMD Radeon R9 M370X with 2GB GDDR5 memory


I have added this entry to my /etc/fstab   /dev/sdb1 /user_data xfs rw 0 0   Which works fine, the issue i am getting it sometime i remove this drive and when i do and  reboot my machine it goes into emergency mode.  I have tried adding   /etc/systemd/system/local-fs.target.d/nofail.conf    with  OnFailure=  in it but i  still get the same result  is there something else i can do to stop this happening   Thanks


journal of materials science template error or epstopdf problem

I have been having a problem writing an article for the Journal of Materials Science. I am using their template and when it comes to figures I get the following result in the text.   I am using the following preamble:  \documentclass[onecolumn,draft]{svjour3} \usepackage[square,numbers]{natbib} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{color} \usepackage{siunitx} \usepackage{graphicx} \usepackage{epstopdf}   and the figure insertion with the following:  \begin{figure}[h]     \centering     \includegraphics[width=\textwidth]{figure3a.eps}     \caption{example}     \label{fig:4} \end{figure}   I am not getting any errors and the converted pdf file looks ok but nothing displays in the text except from what you see in the figure. Can anyone help me with this? Has anyone stumbled on this problem before?  Cheers


I wrote a question about blocking certain characters in passwords. It became tremendously unpopular, and it seemed like everyone wanted to rain on my parade every day.  Eventually, I "got it," agreed completely with what people were saying to me, and just wanted to withdraw my question so that my reputation didn't slide even further downhill.  Unfortunately, the system is designed such that I can't withdraw my question or redeem myself. Instead, I just get daily reputation attacks. That's a terrible system, and it needs to be changed.


Christopher Colombus has made a big mistake and I am confused when I am told there is an Indian in the US because how do I know that is a real Indian from India now working in Silicon Valley or a real Indian living in this continent for many many years and never leaving?


I want to add time delay in my batch file. The batch file will be running silently at backgorund. Please help me.


How do I know which spokes to get for my wheel?

I have a  and under description for Spokes it says "Stainless PG"...but when I look for spokes there are a multitude of sizes, thicknesses, butted, double-butted, etc.!  How do I know what to get for my bike to replace a broken spoke?


How do I prove that the integral ${\displaystyle\int_0^1}{\dfrac{\ln(x)}{1-x^2}dx}$ converges?

How do I prove that the integral ${\displaystyle\int_0^1}{\dfrac{ln(x)}{1-x^2}dx}$ converges? I tried to find a converging on $[0,1]$ function $g(x)$ such as $g(x) > \dfrac{-ln(x)}{1-x^2}$, but I couldn't succeed in finding it as of yet.


I have created a KeyListener and whenever I press W (the specified key) nothing prints out like I told it to. I have tried looking around stack exchange and many other forums to come to no conclusion.  Code:  package com.software.manders;  import java.awt.FlowLayout; import java.awt.event.KeyEvent; import java.awt.event.KeyListener;  import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel;  public class game implements KeyListener {     //0 = English, 1 = Korean.     public static int languageStatus = 0;     public static int gameStatus = 0;     static JFrame frame = new JFrame();      public static void frameMaker() {         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);         frame.setVisible(true);         frame.setResizable(false);         frame.setTitle("경기");         frame.setSize(600, 600);          new game();     }      public game() {         if (gameStatus == 0) {             JPanel p = new JPanel();             JLabel lab1 = new JLabel();             p.setLayout(new FlowLayout());             p.add(lab1 = new JLabel("Please select a language : "));              JLabel lab2 = new JLabel();             p.add(lab2 = new JLabel("Press A for English"));              JLabel lab3 = new JLabel();             p.add(lab3 = new JLabel("Press B for Korean"));              frame.add(p);         }     }      @Override     public void keyPressed(KeyEvent e) {         int id = e.getKeyCode();          if (id == KeyEvent.VK_W) {             System.out.println("W is pressed");         }     }      @Override     public void keyReleased(KeyEvent e) {         int id = e.getKeyCode();          if (id == KeyEvent.VK_W) {             System.out.println("W is released");         }     }      @Override     public void keyTyped(KeyEvent e) {      }      public static void main(String[] args) {         frameMaker();     } }


Do options get repriced at the end of the day, or the beginning?

All else being held constant, an option loses value as its expiration date approaches.  Say it's Friday morning and I have an option that expires 1 week from now, next Friday. Will that option lose value incrementally over the course of each day, or is it repriced when the market opens each day? When is its time-value recalculated?


Trouble finding how I can plug in this Molex connector from a Laptop Fan

I recently bought this fan, I am trying to power it for an external project that doesn't revolve around laptops; however, I don't know how to get power to the fan without cutting off the molex connector and stripping the wires.   I know this is a female molex connector, but I can't find any male heads that even remotely fit this type of product, so I ask you guys if you know of the specific molex connector that I can use to plug into this connector and get power to it.   Thanks


Is $\; \infty = \frac{1}{0}$? My teacher says no but he wouldn't explain it. My question is why $\; \infty \neq \frac{1}{0}\;?$  My thinking:  Let $\frac{1}{x}=p$   Now as $x$ becomes smaller $p$ gets bigger. Ultimately when $x$ is smallest in magnitude then $p$ is largest which is what infinity is. Can anyone help me out?  PS: I have just started Calculus, therefore please try to give answers according to the level of my understanding


I have a railway reservation in sleeper from Jaipur to Pune and boarding point at Ratlam. Will I be allowed to take my seat at Ratlam OR the TT will cancel it and allocate to others?


Changing while($data = mysqli_fetch_assoc($sql)) into PDO

So i have this code:
 <?php $sql = $koneksi->prepare("SELECT * FROM lapangan ORDER BY id_lap DESC"); if($sql->rowCount() == 0){     echo "There is no product!"; }else{     while($data = mysqli_fetch_assoc($sql)){                 ?>

                                      <img src="<?php echo $data['lap_img']; ?>" style="max-width: 300px" />

<?php echo $data['lap_name']; ?>

<?php echo $data['lap_ket']; ?>

                                      <a href="detail.php?id_lap=<?php echo $data['id_lap'];?>" data-theme="a" data-iconpos="notext" data-role="button">Detail                     <a href="detail.php?id_lap=<?php echo $data['id_lap'];?>" data-theme="g" data-iconpos="notext" data-role="button">Lokasi

             <?php              }           }            ?>
   I wanted to change mysqli_fecth_assoc into PDO. I've searched through some tutorials and it doesn't give me an answer (maybe, because its using loops?). Can anyone help me?


I encountered with these sentences :  No work tomorrow because holidays!  Of course evolution is true, because science.  "BECAUSE + NOUN" is a new usage to me. I think 'because' has been used here as a preposition. Could you please explain this usage?


existence of uncountably many subsets of natural numbers

Prove that $\mathbb{N}$ contains uncountably many infinite subsets $(N_{\alpha})_{\alpha \in \mathbb{R}}$ such that $N_{\alpha}\cap N_{\beta}$ is finite if $\alpha \neq \beta$.  I think we have to assume that $\mathbb{N}$ has only countably many subsets of that kind and then arrive at a contradiction due to the finiteness of the intersection of any two distinct subsets between them. But I am unable to find the correct argument. What will be the possible approach here?


Derivation of $E=pc$ for a massless particle?

In classical mechanics, massless particles don't exist because for $m=0$, $p=0$.  The relativistic relation between energy, mass and spatial momentum is: $E^2= (pc)^2 + (mc^2)^2$ . So it is said that setting $m=0$ in the first equation you get $E=pc$.  How could setting $m=0$ in that equation give you $E=pc$ whilst $p$ appears in the equation and we know $p=γmu$? If you set $m=0$ you will have indeterminacy due to "$γm$". It seems to me like we are doing a "trick" in order to get the $E=pc$. Perhaps there is another proof for this relation?


Find factor $f(x)$ conmmon to two quartic equation

Let $f(x) = x^2 + bx + c$, where $b, c ∈ R$. If f(x) is a factor of both $x^4 + 6x^2 + 25$ and $3x^4 + 4x^2 + 28x + 5$, then find $f(x)$  My approach ,on dividing both quartic equation by $f(x)$ remainder is zero, but not getting the answer


public class sss {    public static void main(String[] args) {     int[] array = { 1, 2, 3 };     change(array);      for(int i=0;i<array.length;i++)         System.out.println(array[i]);    }    public static void change(int [] array)   {       int[] temp = new int[4];       for (int i =0; i<temp.length;i++)           temp[i] = i;       array =  temp;   }  }   Im trying to change my array, Why is the output is 1,2,3 and not 0,1,2,3 ? Thanks.


Show that $\mathbb{Q}\times \mathbb{Q}$ is denumerable

I am new to functions and relations, and with some concepts I am not so familiar. I have a question in an homework:     Show that $\mathbb{Q} \times\mathbb{Q}$ is denumerable.   From what I understood, denumerable means that it is infinitively countable. There are some  on the web about this topic, but I am still not understanding their explanation, maybe because they are not explained so easily (for me).  From what I understood, a set is denumerable if there's a relation with the natural numbers (but I am still not understanding what is this relation).  I have heard also about equinumerous sets (contain a bijective function = onto + one-to-one function), but I cannot relate this information with the problem to try to solve it.


Class attribute not reading on select tag using append function js

I have created a dynamic table where by a click of a button it will generate a new row every time the button is pressed. Everything works as it supposed to but the class attribute in the select tag or any other input does not work properly. How do I get it to work. Any Idea??  Here is the .js code that works and adds new row on button click:          $('.plusbtn12').click(function () {             $(".quoteTable12").append('
<select class="js-select2 form-control c_solutions" name="i_solution[]" style="width: 100%;" data-placeholder="Choose one.."></select>	<input class="form-control" type="text" name="i_quantity[]" placeholder="Quantity">	<input class="form-control c_costing" type="text" name="i_cost[]" placeholder="Cost">
');              var options = "";              $.getJSON("getSolution12.php", function (data) {                  for (i = 0; i < data.length; i++) {                     options += "<option>" + data[i] + "</option>";                 }                  $('.quoteTable12 tr:last').find('.c_solutions').html("");                 $('.quoteTable12 tr:last').find('.c_solutions').append(options);                 $(".c_solutions").change();              });         });


Cannot install YouTube app on Tecno devices (Android Go)

I am using a Tecno Pop 2 Power device. It runs on Android 8.1 (Oreo, Go Version). It's a new device. When I launched it, it came pre-installed with the "YouTube Go" app, which is in no way a replacement for the traditional YouTube app. When I try to download YouTube from the Play Store, it downloads but doesn't install. Other applications install just fine, except YouTube. Is there a way to install it? Something I'm not doing right?


How can I recover a Microsoft Office 2013 product key?

I have Office 2013 installed on one of my computers but I have misplaced the product key. It is not set up through my Microsoft account and I would prefer it not be.  How can I recover the license key so I can move the installation?  I've tried running     cscript "C:\Program Files\Microsoft Office\Office15\ospp.vbs" /dstatus   but that only gives me the last 5 characters of the product key. Obviously I need the whole thing.  I've also tried using various 3rd party products (ProduKey, Magic Jellybean Keyfinder, etc), but so far all seem to fail finding Office '13 keys.  Any advice?


Getting warning file permission with root user

What does this warning mean? I got it when executing following command using root at amazon ec2 Ubuntu 14.04 LTS instance:  $ pip install https://github.com/troeger/opensubmit/archive/0.6.2.tar.gz The directory '/home/ubuntu/.cache/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag. The directory '/home/ubuntu/.cache/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.


Traveling inside Schengen state for work - no visa

I have applied for a temporary permit (Poland) 8 months ago and I'm still waiting. I have a stamp in my passport stating that I have applied and waiting for the result, but it is written in Polish. The problem is that my visa is running out and I must travel to another Schengen state for work after my visa expires. I don't go through immigration when travelling within Schengen states, but if my passport gets checked outside Poland,  I might be an 'illegal immigrant' instantly.  What do I do here?


Can an Iranian with Italian residence enter Bulgaria visa free?

I'm going to Bulgaria in a week. I'm an Iranian passport holder, with an Italian residence permit. I read that I don't need to apply for a visa because I have a Schengen residence permit. Is that correct?


How do I explain the lack of situational modifiers in Dungeon World to my players?

How do I explain to players why there are no situational modifiers in Dungeon World? Being used to other RPGs, they would expect modifiers for performing actions in a more challenging circumstance.


Async Task Attemp to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)'

Im Getting invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference at app.VOTD_Data.onPostExecute.  Async Task      public class VOTD_Data extends AsyncTask<Void, Void, Void> {      private String verseData = "";     private String dailyverse = "";     private String verseauthor = "";     private String dailVersePref = "";     private String verseAuthorPref = "";     private SharedPreferences sharedPreferences;      private Context context;      public VOTD_Data(Context context){         sharedPreferences = PreferenceManager.getDefaultSharedPreferences(context);         dailVersePref = sharedPreferences.getString("dailyverse", "");         verseAuthorPref = sharedPreferences.getString("verseauthor", "");     }      public VOTD_Data() {      }       @Override     protected Void doInBackground(Void... voids) {          try {             URL url = new URL("https://beta.ourmanna.com/api/v1/get/?format=json");              HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();              InputStream inputStream = httpURLConnection.getInputStream();             BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));              String line = "";              while (line != null){                  line = bufferedReader.readLine();                 verseData  = verseData + line;             }              JSONObject mainObject = new JSONObject(verseData).getJSONObject("verse");             JSONObject verseObject = mainObject.getJSONObject("details");              dailyverse = verseObject.getString("text");             verseauthor = verseObject.getString("reference");              sharedPreferences                     .edit()                     .putString("dailyverse", dailyverse)                     .putString("verseauthor", verseauthor)                     .apply();           } catch (IOException | JSONException e) {             e.printStackTrace();         }          return null;     }      @Override     protected void onPostExecute(Void aVoid) {         super.onPostExecute(aVoid);          //Daily Verse Activity         DailyVerse_Activity.data.setText(dailyverse.toString());      } }   Main Activity  public class DailyVerse_Activity extends AppCompatActivity {       public static TextView data;      private ImageView banner;      @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_daily_verse);          data = (TextView) findViewById(R.id.dataText);          VOTD_Data process = new VOTD_Data(DailyVerse_Activity.this);         process.execute();       }      //On Back Pressed     @Override     public boolean onSupportNavigateUp() {         onBackPressed();         finish();         return true;     }  }   XML  <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:tools="http://schemas.android.com/tools"     android:layout_width="match_parent"     android:layout_height="match_parent"     tools:context=".DailyVerse_Activity">      <TextView         android:id="@+id/dataText"         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:textColor="#000"         android:gravity="center"         android:hint="Verse Data"         />  </RelativeLayout>   Im Getting invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference at app.VOTD_Data.onPostExecute.app.VOTD_Data.onPostExecute(VOTD_Data.java:88)         at app.VOTD_Data.onPostExecute(VOTD_Data.java:18)


How can I force my Google chrome account to update my bookmarks

I use three different computers and sign in to each one with the same Google Chrome account, but the bookmarks do not seem to be updating.  For example I add a bookmark when signed in on one pc, then open chrome on one of the other pc and it is not there, is there a way to force it to update the bookmarks and histrory etc.


Ways to measure distance from multivariate Gaussian (Mahalanobis distance)

I have a cluster of p-dimensional points and given a new p-dimensional point $x$ I want to determine whether or not it is likely to belong to this cluster.   The cluster is made up of $n$ p-dimensional points, I am making the assumption that these points are drawn from a multivariate Gaussian distribution with sample mean ${\hat{\mu_X}}$ and sample covariance matrix $\hat{\sigma_X}$.  Given a new point $x$ I am trying to decide if it is likely to belong to this cluster using the following threshold on the : $$\frac{n}{(n-1)^2}\left(X_i-\hat{\mu}_X\right)'\hat{\sigma}_X^{-1}\left(X_i-\hat{\mu}_X\right)>B_{0.95}\left(\frac{p}{2},\frac{n-p-1}{2}\right)$$  However, some clusters have very few sample points $n$ in which case calculating the inverse covariance matrix $\hat{\sigma_X}^{-1}$ becomes impossible.  Are there any other equivalent or more appropriate measure I can use in this case?


How to automatically grep the corresponding author name using authblk.sty

Using authblk.sty, I need to automatically grep the corresponding author name string. But I don't how to execute this concept. I think etoolbox is helpful for this logic.  corresauthor is the key to capture the author name and put the * symbol on the author name like Keith Lindsey2*.  corresaddress={address text here} specifies the name and address to be printed on the particular call out place.  My tex coding is:  \documentclass{article}  \begin{document}    \title{Hormonal crosstalk for root development: a combined experimental and modeling perspective} \author[1]{Junli Liu} \author[2]{James Rowe} \author[2,**corresauthor,corresaddress={is Professor of Plant Molecular Biology in the School of Biological and Biomedical Science sat Durham University, UK}**]{Keith Lindsey} \affil[1]{Integrative Cell Biology Laboratory, School of Biological and Biomedical Sciences, The Bio physical Sciences Institute, Durham University, Durham, UK} \affil[2]{Integrative Cell Biology Laboratory, School of Biological and Biomedical Sciences, The Bio physical Sciences Institute, Durham University, Durham, UK} \maketitle  \end{document}   My required output is:     Please suggest how to get this output using this concept.


Is it possible to apply for Ph. D. program in Physics with a CS background?

Currently i am doing BE in cs. Is it possible to apply for a graduate program in theoretical physics without having a bachelor's degree in physics or mathematics?


What does $\lim_{x\to4} \frac{1}{x-4}$ equal?

$$\lim_{x\to4} \frac{1}{x-4}$$ Would it be correct to say that the limit is undefined because the denominator would be $0$?


How does object instantiation works for Interface

So I have some fundamental gap in understanding. I create Path object - Path p = Paths.get("/"); So Path is interface thereby it cannot be instantiated. But Paths.get() method has Path return type. I know it is common practice to use interface object reference. But how does it work under the hood? I thought it creates some anonymous class implementing Path interface. But the I tried to invoke .getClass() method on Path object and it returned: class sun.nio.fs.UnixPath. Please explain briefly how does it work.


Importing KML and style information into Geoserver

So I'm working on a project that's been in development for over a year, but I only recently got involved. My task involves converting roughly 2,500 KML files into another format, importing these files into a Geoserver, and then copying over the associated style information for each file. I realize that Geoserver allows you to import KML files directly, however, our files never seem to render correctly, and my boss would like to move away from KML format for philosophical reasons.   Using ogr2ogr, I've tried to convert these files into ESRI Shapefiles, however the conversion process only worked on roughly a third of the files and erased some of the metadata called for in the style information. The files that didn't convert code for polygons and points, which I've read can be an error for other programs like QGIS.  I've also tried to put all of the KML files into a PostGIS database and convert them like that. However, that seems to delete all of the data leaving essentially blank tables for import.  TL;DR I need to find a way to convert 2,500 KML files into a format usable by Geoserver, and will work with XML style information. I'm a complete GIS noob and this is my first time posting, so I'm sorry if this seems a bit ridiculous.


How can I print a variable with padded center alignment?

How can I print $myvar padded so that it is in the center of the terminal, and to either side are = to the edge of the screen?


How to restore re-created default user directories to Files quicklist?

I deleted and later re-created the Documents folder in my home directory. It no longer appears in the Files quicklist. You can see in the screen shot below that several bookmarks are present among the home directories, but Documents is not there anymore. I can add and remove bookmarks in Nautilus and they appear and disappear from the quicklist, which is the expected behaviour.  How do I restore the original functionality such that existing default user directories (Desktop, Documents, Music, etc...) are listed in the Files quicklist along with dynamically added Nautilus bookmarks?    I know I can create a custom quicklist for Files by manually creating and editing a .desktop file ~/.local/share/applications/nautilus, but this gives me a static quicklist (which may not pick up newly added Nautilus bookmarks?).  A note about the default user directories - once deleted, re-creating them is not the same as if the originals were left in place. The new folder icons are generic (easily fixed) and an edit has to be made to ~/.config/user-dirs.dirs to restore them to Nautilus' Places menu, but I cannot figure out how to get them back in the Files quicklist.


Why should voltmeter have infinite resistance?

My book Isc Nootan 12th reasons for the question that when a voltmeter is connected in parallel and if it had less resistance it would draw some current and potential drop across resistor to be measured will decrease thus an error.In order to avoid this voltmeter has very high resistance.What i dont get is if connect voltmeter across resistor the net resistance in circuit would decrease and thus current drawn should increase.This increase current only passes through voltmeter thus there would be no change in current flowing through resistor,then how is above reasonable?


Suppose $R$ is ring with unit and $a$ is a nonzero element of the ring. If there are two distinct elements $b,c$ such that $ab=ac=1$, show that there are infinite elements $x$ in $R$ such that $ax=1$.


Prove by mathematical induction: $x^n - y^n$ is divisible by $x - y$, for all positive integers $n$.

Here is what I have so far: Base: When $n=1$, we have $x^1 - y^1 = x - y$. Hence, P(1) is true. Inductive hypothesis: We assume that P(k) is true: $x^k - y^k$ is divisible by  $x - y$. That is: $x^k-y^k=(x - y)z$, for some integer $z$ Inductive step: We show that P(k+1) is true. That is: $x^{k+1} - y^{k+1} = (x - y)z$ I don't quite know where to go from there.


How can I use SVGs with pygame (or perhaps display PNGs at a higher definition)?

I'm trying to make a chess opening trainer with Pygame. Graphically, it's incredibly simple; it works like a slideshow, I am only blitting a single image to the screen at a time which updates when I press the return key. I am using chess.svg to generate an SVG of the current game state. Not being able to use SVGs natively with pygame means that I have been converting the SVG to a PNG. Viewing the PNG on my computer, it's very clear.  However when pygame displays the image, it's very blurry.  Ideally I would like pygame to display the SVG so I don't have to worry about the resolution at all. All I found on pygame and SVGs was this  from 12 years ago. In 2018, an answer was posted stating that the original methods no longer worked. However, now, in 2021 the methods given in 2018 no longer work either; I tried, and one comment also confirms this. If using SVGs is not possible, that's fine, provided I can get pygame to display the PNG at a greater definition than it currently does. Even if I make screen = pygame.display.set_mode((width, height)) fullscreen, it's still blurry. I can't seem to find anything on that, so I'm not sure that's the issue here. Here's a simplified version of my code to demonstrate the graphical part: import pygame from pygame.locals import * import chess import cairosvg import chess.svg import chess.pgn  ##Setup Pygame: pygame.init()   width, height = 640, 640 screen = pygame.display.set_mode((width, height))  ## MAIN ##  board = chess.Board()                  #Step 1: Create image boardsvg = chess.svg.board(board=board) f = open("image.SVG", "w") f.write(boardsvg) f.close()  #scale cairosvg.svg2png(url="image.svg", write_to="image_scaled.png", scale=3.0)  #Step2: Blit the image image = pygame.image.load('image_scaled.png') image = pygame.transform.scale(image, (640, 640)) screen.blit(image,(0,0)) pygame.display.flip()  Does anyone one know what I need to try? Cheers.


Which is the correct country to apply for Schengen visa?

Travel questions regarding my partner (a South African national residing in the U.K.).  We have two holidays planned in very short succession from each other. The first is to Country A from the 15th June until the 20th, 5 nights. From there we would travel back to the UK before flying to Country B on the 29th June, where we would remain until we fly to country C on the 6th of July before returning home on the 11th.  This makes 5 nights in country A. Return to country of residence then a second separate trip with 7 nights in country B and 5 nights in country C.  We initially thought that country B was the correct country to apply to, as this is where the longest stay would be in the period of the visa. Although they responded to our booking request, we were told that it was country A we need to apply through, as we would be returning to the country of residence between our trips. Upon receipt of this, and with time beginning to dwindle, we booked an appointment slot with country A and forwarded the query to double check. They today have said that they are not who should be dealing with it, and it is, in fact, country B.  Any ideas? At the moment it is looking like we can only apply through country A and hope they don't reject it, as country B has been refusing. We are considering just visiting country A and C so that the visa appointment we have will be successful, although we really don't want to have to do this.


Where can I get a self loading CD with Ubuntu OS?

Where can I get a self loading CD with the Ubuntu OS?


I'm trying to delete some files in a directory using some commands. Using loop for i in $(ls -tr $path); ... i need to know length of $(ls -tr $path)  How to get the number of files in directory $path without using one more loop?  The very problem is to delete the files in the folder. The resultant folder have to contain no more than 10 most recent files.


"[class] was not declared" but CLion sees it

I have a header file, let's call it SomeClass.h in which a class is defined as usual: class SomeClass { ... };  The implementation of SomeClass is in another file, say SomeClass.cpp. Then I have another header file, say AnotherClass.h which tries to use the SomeClass class to define another class, as shown below. #include <SomeClass.h>  class AnotherClass { ... protected:   std::unique_ptr<SomeClass> s;  // (*) };  when I try to compile, I get the following error: error: 'SomeClass' was not declared in this scope  but this is quite surprising, since CLion is not detecting this error and when I click on SomeClass in the instruction commented with // (*) above, CLion correctly goes to the definition of SomeClass in SomeClass.h So the question is: why is CLion seeing SomeClass while the compiler is not seeing it?


Cartoon: Yellow Robot helps Princess escape from Coup d'état

I'm trying to find a cartoon that begins with an empire in Coup d'état. The king ordered the princess to escape while he held back the attackers. He sent her to a lab or something where she found a yellow robot who was assigned to protect her and they escape at the end of the episode.  The enemies have their own robot who looks like the yellow one. It is implied that both robots were created for the same purpose (protecting the princess) but he was too violent and volatile, so, even though he was superior in combat (he is running a simulation where he fights and obliterates the other robot), the yellow one is the one chosen for the task. In the next episode (or the third one; I don't remember very well) the princess and the yellow robot go to a mine to recover an artifact, which is some kind of hammer. The miners were ordered to hide there in case the robot was ever needed.  That is what I can recall of the series: It was shown in South America; only 3-5 episodes, really early in the morning. The robot was a bright yellow like Bumblebee from Transformers, but the design was more like a more rounded iron giant. It was pretty big: enough for the prince to ride his shoulder. I don't recall much of the princess besides she was in a classic princess-like long dress and had pretty long hair.   I'm pretty sure it is not Asian made. And for what I recall it was 3D, not drawn. I'm not too sure how old it is, since cartoons often take years before they make it to free TV, but the 3D was pretty good, so I don't think it is older than 10 years.


Penalty to withdraw from a new Roth IRA for first time home buyers?

My wife & I are 28 and plan on purchasing our first home in the next 1-3 years.  Right now our assets are in two places:   403-b that I will not touch for the next 30+ years FDIC-insured savings account earning 1% interest   I have the option to start a Roth IRA account under .  My understanding of Roth IRAs is , but I understand that first time home buyers can withdraw $10,000 ($20,000 joint) to purchase a new home.  However, are there any restrictions to taking this money out?  It's unclear to me if a  applies to first time homebuyers (ie. would we incur a 10% penalty for withdrawing up to $10,000 ($20,000 joint) on a Roth IRA that is less than 5 years old?)  Thanks for  for suggesting that I migrate this question .


Why does Li-Po battery voltage drop under load?

I have very low background in electronics.  I have a Li-Po battery connected to an electric motor. The question is:   Why does battery voltage drop under load? Why is each cell of a Li-Po battery limited to 3.0 V (discharging)? Why is each cell of a Li-Po battery limited to 4.2 V (charging)?


Is every buildable set that exists, by Extensionality, unique in ZF Set Theory?

I am reading An Introduction To Set Theory by Professor William A. R. Weiss, and during chapter 3, on the proof of $\forall x \forall y \exists z \ z = x\times y$ (the euclidean product exists), there's the following:  We obtain: $$\forall t \in y \ \exists q \ q=\left\{ v : \exists u \in x \ v=\langle u,t \rangle \right\}$$ By Extensionality, in fact, $\forall t \in y \ \exists ! q \ q=\left\{ v : \exists u \in x \ v=\langle u,t \rangle \right\}$.  This step seems intuitively clear, but it also doesn't seem like an special case, it seems like this logic could be applied to any set built using builder notation. So my question is: For any arbitrary set $x$ and any abritrary formula $\Omega$, does $\exists q \ q=\left\{ v:\Omega \right\}$ imply, by Extensionality, that $\exists ! q \ q=\left\{ v:\Omega \right\}$?


How to sum binomial coefficients which are multiples of 3?

Basically   $\sum_{i=0}^{33}\binom{99}{3i} $   I have read about this .  I am looking for a conventional approach. Like the one we use in $\sum_{i=0}^{n}\binom{2n}{2i} = 2^{2n-1}$


using a method from another file without including it

I have two .c files which I compile over a makefile.  foo.c:  void foo() {     printf("this is foo"); }   main.c:  #include  <stdio.h>  int main() {     printf("this is main\n");     foo(); }   the makefile looks like that:  all: main.o foo.o     gcc -o prog foo.o main.o  main.o: main.c     gcc -c main.c  foo.o: foo.c     gcc -c foo.c   So the question is: how can foo.c use printf() without me including stdio.h AND how can main.c use the method foo() without me including foo.c.  My guess/research is that the makefile works as a linker. But I dont have prove for that and want to understand how this works excactly.  Correct me if I misunderstood something.


Stack Overflow is very useful, and much of that comes from the code samples.   Yet again, I am having to scroll to the right to see all of the code in an answer I am looking at, while at the same there is a huge amount of whitespace at the left and right of my screen on a desktop.   Could the layout not take this into consideration and allow the code window more space?


Is it okay to dispute the premise of a question?

In the limited number of questions I have asked on Stack Exchange, I have had several comments and answers that are not answering my question, but are instead saying that I should be asking something else.  The most recent example is at , which basically asks how to increment the value of a GUID variable by 1. In the comments, user "atlaste" explains why this may be a bad idea, and that some people use dedicated hardware for similar things, but nothing relating to my question or its phrasing.  I understand this in general -- in my own life I find that when people come to me with a question, I often want to better understand where they are coming from to make sure my answer really fits their problem. I see this partly as a way to reduce the risk of miscommunication, and partly to reduce the risk that the person did not think the problem through.  But it is my predisposition to think that in a Stack Exchange site, we should assume that the questioner knows at least approximately what they want. Because even if the question was not the best for that one person, the answer should apply to the question so that future users will find this question and answer to be useful.  So my question is, to what level is it acceptable to dispute the premise of the question that is being asked?  This is related to , but I believe slightly different. Seeing this as the "XY Problem" assumes that you have that problem. Here I am asking, "To what extent is it okay to assume that the question is an instance of the XY Problem?"  Here is a (somewhat ludicrous) example of a problem, with background, and the question I could ask at the end of it.   I want to have a pretty house I decide that pretty is "feng shui", with all those crazy rules and oblique lines I want to rebuild my garage to have oblong walls I decide to do this be hand, and use a sledgehammer to rip the walls apart I injure my back by doing this with no training I ask the question: "What is the right way to use a sledgehammer so that it does not hurt your back?"   Now if you want to apply the "XY Problem" here, you could question many things. And the more details I give of the background problem, the more you could question the premise.   Why did I use manual sledgehammer instead of some "power" hammer Why did I try to use a sledgehammer without formal training -- go get some real training instead Why did I use a sledgehammer myself -- go pay a contractor instead Why did I use a sledgehammer at all, instead of a saw Why don't I just buy a new house instead Why do I like "feng shui" Why should houses be pretty   In my opinion, you cannot go all the way back up the stack; it is ridiculous to do so. So is it ever okay to debate the premise? How do you know how far is okay to go?


Why the regex  below not working  for the text below   Regex:    (?=.*\berror\b)(?=.*\balarm\b).*   Text :   ns1.alarm.abc  ns2.error.cdb   In other works how to do multiline regex match?


In Clash of Clans there was an update on 9/16 adding a Tie-breaker into the wars, can anybody explain in detail how this mechanism works?


Prove there's a simple path of length $k$ in a simple graph $G$ where all the vertices have degree of at least $k$.   Relevant definitions:  $G$ is a simple graph that consists of a vertex set $V(G) = \{v_1, v_2, ..., v_n\}$ and an edge set $E(G) = \{e_1, e_2, ..., e_m\}$ where each edge is an ordered pair of vertices. The edge $\{u,v\}$ is denoted $uv$.  A walk of length $k$ is a sequence $v_0,e_1,v_1,e_2,...,e_k,v_k$ of vertices and edges such that $e_i=v_{i-1}v_i$ for all $i$. A path is a walk with no repeated vertex.   My attempt:  Induction, for $k=1$ it's obvious.  Suppose for $k-1$ and we'll prove for $k$.  Let $G$ be a simple graph such that $\forall v \in V : d(v)\ge k$.  We can assume that there are at least $k+1$ vertices since there are $k$ neighbours to every vertex.  Let $v_0$ be some vertex, it has $k$ neighbours, we'll move to one of its neighbours say $v_1$ and remove $v_0$. So now there are $k$ vertices with a degree of at least $k-1$ and from the induction hypothesis we'll have a path of length $k$.  Is using only $k$ vertices from $n$ right? Does it keep the generality when using only all the neighbours of $v_0$?


So my physics examinations are coming up and I was going through my notes on waves, but I realized that there were some discrepancies.   In my notes, the energy of a wave is directly proportional to the square of the amplitude, ie. $E \propto A^2$  However, I recalled that, in one of my physics lessons, our physics teacher told us that the energy of a wave can be calculated using $E=hf$, where $h$ is the Planck constant and $f$ the frequency.  Hence I was rather confused and tried searching google for answers but couldn't find any suitable ones. To the best extent of that research, what I found out was (apparently) (for visible light), the frequency of the wave could be used to calculate the energy of the wave, while the amplitude was used to determine the intensity of the wave.  So I was wondering, firstly, whether the above statement was correct, and secondly, in the event it is correct, whether it would be applicable to all kinds of waves, (ie. Sound waves, water waves, other EM waves, etc.), and thirdly, back to the original question, how do we calculate the energy of a wave?  Thanks. :)


Alternatives to LIMIT and OFFSET for paging in Oracle

I'm developing a web application and need to page ordered results. I normaly use LIMIT/OFFSET for this purpose.  Which is the best way to page ordered results in Oracle? I've seen some samples using rownum and subqueries. Is that the way? Could you give me a sample for translating this SQL to Oracle:  SELECT fieldA,fieldB  FROM table  ORDER BY fieldA  OFFSET 5 LIMIT 14   (I'm using Oracle 10g, for what it's worth)  Thanks!    Answer: Using the link provided below by karim79, this SQL would look like:  SELECT * FROM (     SELECT rownum rnum, a.*      FROM(         SELECT fieldA,fieldB          FROM table          ORDER BY fieldA      ) a      WHERE rownum <=5+14 ) WHERE rnum >=5


How can I check if $$12^{2013} + 7^{2013}$$ is divisible by $19$?  Also, how can I format my questions to allow for squares instead of doing the ^ symbol.


How I can automatically add a page if the total number of pages is odd?

I need automatically add a blank page (also without document header, numbering and footer) at the end of the document, if the total numbers of pages is odd. How I can do that? And preferably without using any additional package. :)


Terminate running commands when shell script is killed

For testing purposes I have this shell script  #!/bin/bash echo $$ find / >/dev/null 2>&1   Running this from an interactive terminal, ctrl+c will terminate bash, and the find command.  $ ./test-k.sh 13227 <Ctrl+C> $ ps -ef |grep find $   Running it in the background, and killing the shell only will orphan the commands running in the script.   $ ./test-k.sh & [1] 13231 13231 $ kill 13231 $ ps -ef |grep find nos 13232     1  3 17:09 pts/5    00:00:00 find / $   I want this shell script to terminate all its child processes when it exits regardless of how it's called. It'll eventually be started from a python and java application - and some form of cleanup is needed when the script exits - any options I should look into or any way to rewrite the script to clean itself up on exit?


Is it alright to use lowercase "i" or should you always use "I" (uppercase)?

I frequently edit questions on StackOverflow, and I always fix the "i" into "I". See this .     When i I start my tomcat, i I am getting this problem.   How could i I resolve this problem.   Am I right to do so?     points out an interesting thread illustrating that debate:    the MetaSO question "" (and ):      The point of text on a site like this is to communicate.   Why do you want  to make it harder to communicate than it has to be?   You may like writing with no capitalization, but I think it's pretty clear that people prefer reading with capitalization.   If you don't care about making life easier for those trying to help you, why do you think anyone will bother helping you in the first place?    The article "" also refers to norms.      Readers of the modern English language have grown accustomed to certain norms. Paragraphs, for one. Punctuation. Consistent spelling. And, of course, capitalization.


New kernel broke the USB cameras on Ubuntu Desktop 16.04

The new kernel versions (4.4.0-186-generic and 4.4.0-187-generic) the ubuntu cannot recognizes my USB cameras (neither the original from the laptop or another USB webcam). If I start on the previous kernel version (4.4.0-185-generic), both work fine. Here is the result of "lsusb": ... Bus 001 Device 003: ID 04f2:b537 Chicony Electronics Co., Ltd  Bus 001 Device 009: ID 046d:0892 Logitech, Inc. OrbiCam  ... But they do not appear as /dev/video0 and /dev/video1, and cannot be detected by cheese, or zoom, or meet, and etc. Is there any additional driver required for those kernel versions, or it is really broken? Thank you


After reading  and , I want to remove the title attribute from all links of my blog, as that is good from accessibility point of view. How this can be achieved?  UPDATE  I found a  how to remove title attribute from images, but it doesn't work for me.


I have this root cronjob:  # Edit this file to introduce tasks to be run by cron. #  # Each task to run has to be defined through a single line # indicating with different fields when the task will be run # and what command to run for the task #  # To define the time you can provide concrete values for # minute (m), hour (h), day of month (dom), month (mon), # and day of week (dow) or use '*' in these fields (for 'any').#  # Notice that tasks will be started based on the cron's system # daemon's notion of time and timezones. #  # Output of the crontab jobs (including errors) is sent through # email to the user the crontab file belongs to (unless redirected). #  # For example, you can run a backup of all your user accounts # at 5 a.m every week with: # 0 5 * * 1 tar -zcf /var/backups/home.tgz /home/ #  # For more information see the manual pages of crontab(5) and cron(8) #  # m h  dom mon dow   command MAILTO="" * * * * * /usr/bin/python3 /var/scripts/monitoring/load.py > /var/log/cron.log   The problem is that the cron log file is always empty, meaning the script is not executed, but when I run "/usr/bin/python3 /var/scripts/monitoring/load.py" manually in the CLI, it is all fine.


Last week plumber installed new vanity faucet, supply lines in small hall bath.  Now the shower in that bathroom and the one in master bath do not have water until the sink is turned on...when sink is turned off the showers go off and there is no hot water...HELP!!


A function $f$ such that $f \in L_1$ but $f \notin L_p$ for $p>1$

I want find a function $f: [0,1] \mapsto \mathbb{R}$ such that $f \in L_1[0,1]$ but $f \notin L_p[0,1]$ for all $p>1$.  My attempts:  First I thought in the family of functions $\frac{1}{x^\alpha}$ but this function belongs to $L_q$ iff $\alpha \cdot q \leqslant 1$ so I need find $\alpha$ such that: $\alpha <1 $ and $\alpha \cdot q \geqslant 1$ for all $q>1$ but this its impossible!!   After other attempts using variations and combinations of $1/x$, $ln x$ and $e^x$ I researched in the mathstack and found this questions:   The kingkongdonutguy's question is exactly what I was looking for, but I do not understand very well the Tomas' (and of Davide) hint... My interpretation:  Choice two sequences $\{a_n\}_{n \in \mathbb{N}}$ and $\{t_n\}_{n \in \mathbb{N}}$ com $a_n,t_n \to 0$ now make a sequence os disjoint intervals $\{I_n\}_{n \in \mathbb{N}}$ such that, for each $n$,$0 < m(I_n) < t_n$ and $\bigcup I_n = [0,1]$. Define a function: $$f(x)= \sum\limits_{n=1}^{\infty} a_n \cdot \chi_{I_n}(x)$$ Make a simple calculation: $$\int\limits_{0}^{1} f(x)dx = \sum\limits_{n=1}^{\infty} \int_{I_n} a_n dx = \sum\limits_{n=1}^{\infty} a_n\cdot m(I_n) \leqslant \sum a_n \cdot t_n$$ So I need choice $\{a_n\}$ and $\{t_n\}$ such that $\sum a_n \cdot t_n$ converges but $\sum a_n ^{p} \cdot t_n$ not converges for $p>1$. The problem: using  we have $$\lim_{n \to \infty} \frac{a_n^p \cdot t_n}{a_n\cdot t_n} = \lim_{n \to \infty} a_n^{p-1}=0 $$(because $p>1$) so don't is possible this choice ...  Also found this question  but I could not adapt for a finite domain..  Someone can give me a (other) hint to construct this function??


Efficiently remove file(s) from large .tgz

Assume i have an gzip compressed tar-ball compressedArchive.tgz (+100 files, totaling +5gb).   What would be the fastest way to remove all entries matching a given filename pattern for example prefix*.jpg and then store the remains in a gzip:ed tar-ball again?  Replacing the old archive or creating a new one is not important, whichever is fastest.


I would like to format a string based on the input. For example if the line count is 1, the output must be image00001.png and if the line count is 400, the output is image00400.png I use the following to do so filename = "image%05d.png".format(line_count)  but it doesn't work as expected. What am I missing?


Using French Keyboard during installation

I am trying to install Ubuntu 14.04.3 LTS on the second partition of my PC. I have created created a bootable stick and copied the image using a program called rufus. I have modified my boot sequence and Ubuntu starts properly from the stick.  When I choose the option of installing Ubuntu, the keyboard is set to EN, but I have a FR keyboard. I have found the keyboard options, but it does not offer FR as an option. This problematic, since I have to enter keywords during the installation (Wifi, etc...).  How can I solve this? Thanks.


Can he's always be used instead of he is?

The word he's is a contraction of the words he and is. If I want to use the contraction to say     I'm a better driver than he is   I should be able to say/write I'm a better driver than he's, but that just sounds awfully wrong in my head.  Is it correct to say/write      I'm a  better driver than he's   I reckon it might sound silly due to the fact that it sounds like I'm saying I'm a better driver than his when pronounced.


I have a program called f in my $PATH, I can simply execute it by typing f into a terminal. However, typing which f into that same terminal afterwards, it errors out: which: no f in (...), and it gives the full path in brackets (which indeed contains the correct path for f itself).  Using type f however I get the correct result.  Does anyone have an idea why that is the case?    Here are the answers to questions from the comments:   f itself is a symlink to a perl script:  vwos3xz@vwososuvs012:~$ls -l $(command -v f)  lrwxrwxrwx 1 root root 42  2. Aug 2012  /tef/tegf/06_CAE_System/064_soft/PERL_SCRIPTE/bin/f -> ../CRASH_SCRIPTE/FEMSTARTER/fem-starter.pl   In fact, fem_starter.pl itself is a symlink to fem_starter-1.77.pl in the same directory I'm reasonably sure there's no typo in the path because I can simply type f in a terminal and have it run (also, type and command -v work). I set the path in .bashrc, but .bash_profile exists and just sources .bashrc. Also, I have BASH_ENV set to my .bashrc. type f returns f ist /tef/tegf/06_CAE_System/064_soft/PERL_SCRIPTE/bin/f, and command -v returns /tef/tegf/06_CAE_System/064_soft/PERL_SCRIPTE/bin/f. Also, type -a f returns the same as type f. "Have you opened a new window?"... do you mean a new terminal? I did, but that did not make a difference. I used both xterm and konsole, and I did start each from the window manager as well as from another xterm. Everytime, the $PATH was correctly set, but which did not work as expected.


Detect and clean nymaim on Ubuntu server?

I'm trying to figure out why our server has been block at Spamhaus. It comes up with:     139.162.208.xxx is listed in the XBL, because it appears in:      CBL Lookup   Following the link, it says:  This IP address is infected with, or is NATting for a machine infected with the "nymaim" malicious botnet.  "nymaim" is also known as "Gamarue".  More information about Gamarue can be obtained from Proofpoint, and Microsoft.  Gamarue is involved with a variety of malicious things, including backdoor downloads, Banking Trojans and Ransomware.  This was detected by a TCP connection from "139.162.208.xxx" on port "36752" going to IP address "216.218.185.xxx" (the sinkhole) on port "80".  The botnet command and control domain for this connection was "www.ltaet.com".  This detection corresponds to a connection at Mon Sep 9 09:48:26 2019 UTC (this timestamp is believed accurate to within one second).   How would you go about cleaning this up? I've tried a few malware detection tools, but none of them ever come up with anything.   The OS is Ubuntu 16.04  Thanks


I'm asked to      find a power series of the form $\sum a_n x^n$, recognize the resulting series as the expansion of a familiar function, then verify my conclusion by solving the equation directly.     Given $xy'=y$.  However, I'm getting $a_0\sum_{n=0}^\infty (n! x^n)^{-1}$, which doesn't appear to match any functions that I know right now at least.  (I was also expecting something involving $e$ just from looking at it.)  Here's what I got so far:  $$let \ \ y = \sum_{n=0}^\infty a_n x^n$$ $$y'=\sum_{n=1}^\infty na_nx^{n-1}$$ $$xy'=\sum_{n=1}^\infty na_nx^n$$ and since $xy'=y$: $$\sum_{n=1}^\infty na_nx^n=\sum_{n=0}^\infty a_n x^n$$ $$\sum_{n=1}^\infty na_nx^n=\sum_{n=1}^\infty a_{n-1} x^{n-1}$$ $$na_nx^n=a_{n-1} x^{n-1}$$ $$a_nnx=a_{n-1}$$ $$a_n=\frac{a_{n-1}}{nx}$$  taking $a_0=a_0$  $$a_1=\frac{a_0}{x}, \qquad a_2=\frac{a_0}{2x^2} \qquad a_3=\frac{a_0}{6x^3}$$  and generally,   $$\sum_{n=0}^\infty \frac{a_0}{n!x^n}$$  Where did I go wrong?


Set up a render farm with multiple OS and spec

I have quite a few computers at my disposal- about 100 mac pro's bought 2 years ago, just as many windows PC's of varying age (1-3 years), 50 linux machines and a good few terabytes of storage on a central server. I'm seriously considering getting everything together into a cycles render farm. How can I set something up easily and quickly which will make use of everything I've got?


Why should we care about syntactic proofs if we can show semantically that statements are true?

I am talking about classical logic here.  I admit this might be a naive question, but as far as I understand it: Syntactic entailment means there is a proof using the syntax of the language, while on the other hand semantic entailment does not care about the syntax, it simply means that a statement must be true if a set of other statements are also true.  That being said, isn't semantic entailment sufficient to know whether or not a statement is true? Why do we need syntactic proofs?  Granted I know that in the case of boolean logic, proving statements by truth tables gets intractable very fast, but in essence, isn't semantic entailment "superior"? As it does not rely on how we construct the grammar?  Thank you  Edit: Suppose it wasn't the case that finding a satisfying assignment to an arbitrary boolean statement is an exponentially increasing problem, then would we even need syntactic entailment?


Finding x in $a^{x} \bmod  b = c$ when values a,b, and c are known?

If values $a$, $b$, and $c$ are known, is there an efficient way to find $x$ in the equation: $a^{x} \bmod b = c$?  E.g. finding $x$ in $128^{x}\bmod 209 = 39$.


Is there some logic in IC name prefixes?

There are hundreds of prefixes in IC names,  lists a number of them. For some it's easy to see that they refer to the manufacturer's name, like AD for Analog Devices or LT for Linear Technology. Others can be found with several manufacturers, often three letter prefixes: SAA, SAF, SDA, TCA and TDA, to name a few. I wonder if there's some logic in this, like T** being a specific group with subgroup TD*, etc. Is there a logical structure?


How to check if one date period overlapping another date period

So I have this function I created called isDateOverlapping. It takes in (of all type LocalDate):   Start Date 1 End Date 1 Start Date 2 End Date 2   What this function does is it tells me if the 2 date periods are overlapping or not.  For example if I have 1 period from 2019-06-15 to 2019-06-18 and another period from 2019-06-15 to 2019-06-12. It would return true because the 2 date periods overlap.  However my function doesn't seem to always return the right answer. Could you please help.  public boolean isDateOverlapping(LocalDate start1, LocalDate end1, LocalDate start2, LocalDate end2) {      if (start1.isAfter(start2) && start2.isBefore(start1)) {         return true;      } else if (end1.isBefore(end2) && start1.isAfter(start2)) {         return true;     } else if (start1.isAfter(end1) && end2.isBefore(start2)) {         return true;     }      return false;  }


Doing another task while copying a directory

Am on Server 17.10 and am copying a directory that is some 500Gb in size, so is there a way to  continue doing something else while the directory copies?? The transfer has already been started and there is no progress report, only the cursor blinking.


This is with reference to the Sony NEX-5R. I have gotten into the habit of telling Lightroom to convert all ARW to DNG when I import them, in the hope that DNG, being an open format rather than a proprietary, encrypted one, will let me easily access my photos decades from now. It's a nice bonus that DNGs are little smaller than ARW.  Are there any other factors that would affect this decision? Or am I over-doing the longevity part?  To be clear, I don't want to keep both the ARW and the DNG. I don't plan to convert to JPEG and delete the RAW, either.


How to prove that $\mathbb{C}_p$ is not locally compact?

Let $\mathbb{C}_p$ be the $p$-adic complex numbers, i.e. the completion of an algebraic closure $\overline{\mathbb{Q}_p}$ of $\mathbb{Q}_p$. How can one show that $\mathbb{C}_p$ is not locally compact? I know that by scaling and translation, $\mathbb{C}_p$ is locally compact if and only if the closed unit disc $\overline{D}(1):=\{x\in\mathbb{C}_p\ |\ |x|\leq 1\}$ is compact. So in order to prove that $\mathbb{C}_p$ is not locally compact, one has to show that $\overline{D}(1)$ is not compact, which by completeness amounts to showing that $\overline{D}(1)$ is not totally bounded. But how would one go about proving this?


fetch the 1st row from the table for an employee with highest salary

I am searching for a query to find the details of highest paid employee in the entire organization. I am using oracle DB.  Queries which I tried are:  select * from EMP order by SAL desc FETCH FIRST 1ROW ONLY;      ERROR: SQL command not properly ended   select * from EMP order by SAL desc where rownum = 1;      ERROR: SQL command not properly ended   select * from EMP order by SAL desc LIMIT 0 , 1;      ERROR: SQL command not properly ended


MediaPlayer.start() on a null object reference

I've been working on creating an alarm app to run a music track that the user selects. So, after the user selects the track, it is converted from Uri to String by ".toString" method to be able to receive this Uri from a broadcast receiver so that it can be used in MediaPlayer.create(); after converting it back to Uri  Uri.parse(String track);   The problem comes when i try to play this it doesn't work although when I tested this in another activity it worked fine and I checked the uri.getPath() it tells me the path of the track so the problem is not because Uri object is empty.  public class AlarmTrigger extends Activity {     String trackPath;     Uri trackUri;     MediaPlayer mediaPlayer;      @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_alarm_trigger);          trackPath = getIntent().getExtras().getString("Track path");          //getIntent from BroadcastReceiver class         trackUri = Uri.parse(trackPath);         Toast.makeText(this, trackUri.getPath(),Toast.LENGTH_SHORT).show(); // it works fine         AlarmGoes();     }      public void AlarmGoes(){         MediaPlayer mediaPlayer = MediaPlayer.create(this,trackUri);          mediaPlayer.start();     } }   The stack-trace:      java.lang.RuntimeException: Unable to start activity ComponentInfo{com.amr.mineapps.myapplication/com.amr.mineapps.awarm.AlarmTrigger}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.net.Uri.getScheme()' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2747) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2808) at android.app.ActivityThread.-wrap12(ActivityThread.java) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1541) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:165) at android.app.ActivityThread.main(ActivityThread.java:6375) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:912) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:802)  Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.net.Uri.getScheme()' on a null object reference at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1004) at android.media.MediaPlayer.setDataSource(MediaPlayer.java:983) at android.media.MediaPlayer.create(MediaPlayer.java:890) at android.media.MediaPlayer.create(MediaPlayer.java:867) at android.media.MediaPlayer.create(MediaPlayer.java:846) at com.amr.mineapps.awarm.AlarmTrigger.onCreate(AlarmTrigger.java:40) at android.app.Activity.performCreate(Activity.java:6845) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2700) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2808)  at android.app.ActivityThread.-wrap12(ActivityThread.java)  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1541)  at android.os.Handler.dispatchMessage(Handler.java:102)  at android.os.Looper.loop(Looper.java:165)  at android.app.ActivityThread.main(ActivityThread.java:6375)  at java.lang.reflect.Method.invoke(Native Method)


Can I use 5v 5A power supply for 5v 3A circuit

I have a dev board which came without power supply. As per the spec, it works on 5V 3A. I have a spare power supply 5V 5A, can it be used here?  Will there be any issue?


Automatically create appenders with log4net

In a C# code I need to create several log4net loggers with different names to differentiate the logs written. One logger can be called MyNamespace.MyClass.1, another one MyNamespace.MyClass.2, etc. The logs are then written in several files: MyNamespace.MyClass.1.log, MyNamespace.MyClass.2.log, etc.  The problem is that a have to manually add paragraphs in the configuration, each paragraph corresponding to only one logger name.  <appender name="logger1" type="log4net.Appender.RollingFileAppender">   <file value="Logs/MyNamespace.MyClass.1.log" />   <appendToFile value="true" />   <rollingStyle value="Size" />   <maximumFileSize value="2MB" />   <maxSizeRollBackups value="10" />   <staticLogFileName value="true" />   <threshold value="INFO" />   <layout type="log4net.Layout.PatternLayout">     <conversionPattern value="%date [%thread] %level %logger %ndc: %message (%file:%line)%newline" />   </layout> </appender>  <logger name="MyNamespace.MyClass.1">   <level value="INFO" />   <appender-ref ref="logger1" /> </logger>   Is there a solution to generalize for n logger without writing n times this code?


Upgrading to a better quality camera before a wildlife-focused vacation

I'm sure this has been asked many times before, but anything would be helpful.  I'm looking to upgrade from a standard point-and-shoot to a higher quality camera before a safari vacation.  I was leaning more towards dslr than mirorless, but am overwhelmed by determining mm v. zoom factor.  I'm mildly intimidated by breaking the think while trying to change lenses, but I want to make sure I will be able to get good quality photos of wildlife that might be further in the distance, as well as something that will be able to shoot quickly.  I was leaning toward the Nikon D3300.  Any suggestions?


Code leaving random string at end of output


I really confused if there is a function (mostly in physics, functions represents physical quantities) which is not a field? I feel all functions in physics are fields. Is there any functions which are not fields? I see a lot of questions in stackexchange about functions and fields. But no one nail down the difference between functions and a fields in Physics, other than answers resembling textbook explanations.


(Statement) "Ubuntu 14.10 won't work because black screen" solution described here

Please read entirely the question.  I've decided to write this here because I've seen about 15 questions of the same issue:      Ubuntu not showing up screen, all is black.   Well, let's start in the beggining and finish in the end. The Utopic Unicorn update has caused a lot of issues until now, and more is to come. The black screen is caused by, in real, graphics issues. It has nothing to do with X11, nor X Server, nor GRUB2. And why? Here is the answer.  The Utopic update has changed the way how things work, mainly graphical and performance. And as well, the update has changed the package channels. You don't use anymore the word trusty in sources.list, you use utopic. And updating packages consume time. So, as AMD and Intel have specific dependencies, some of them have not been released for 14.10, for example the linux-headers-3.13.0-37 package. And fglrx, for example, needs it for running well. And as there is no version of it for Utopic, catalyst starts to tumble itself down taking with it the whole system.  But luckily, there is an escape:  You need to purge your driver's package from the system and restore X.Org's original settings.  So, to do that, open the tty1 terminal ( Ctrl+Alt+F1 ) and do the following:  If you are using nvidia:  sudo apt-get purge NVidia-*  If you are using Intel:  sudo apt-get install --reinstall xserver-xorg-video-intel  And, if you are using AMD:  sudo apt-get purge fglrx-*  The system itself will feel something is missing, and so will fix itself. Then, go on and type:  reboot  Hope that it helped. And sorry if I made any mistake, if this was the case, be sure to hit the Edit button and fix it.


What is the difference between accessing class methods via "." or "::"?

Given a Ruby class with a static method like  class Foo   def self.bar     puts "Hello"   end end   I always accessed the method via  Foo.bar   However, I just noticed that you can also do  Foo::bar   Why is that? Is there a semantic difference? My initial idea was that it's a matter of treating Foo as a class object (in which case the first version seems plausible) vs. treating it as a "namespace" like a module, in which case the second version makes sense.


How do we wire a new bathroom exhaust fan to our bathroom?

In our attic we have a junction box that has the power wire connected to a hallway ceiling light. Can we tap into that to get power to install a bathroom exhaust fan? We would be putting in a double rocker light switch in the bathroom (top switch would be for the vanity light and the bottom switch would be for the exhaust fan switch). How would we wire this?


gcc: error trying to exec '/usr/lib/gcc/x86_64-linux-gnu/7/cc1': execv: Input/output error

I've searched for an attempted fix for this problem but it seems that people haven't had this problem. When I try to compile a C program with gcc (Ubuntu 18.04, GCC 7.5.0) I get the error as said in the title but if I use g++ it works just fine. What could be the reason for this? (Also fairly new to Linux)


"Edited by" block is not updated after editing tags inline

Go to a question that was already edited by someone else Press "edit tags", edit, "Save Tag Edits" => the "edited <date> (<br>) <user>" block in the center under the post still shows the previous editor and date


What are the theorems of mathematics proved by a computer so far?

By theorems, I mean the ones you can find in an undergraduate course of mathematics, not the ones you can find in a textbook of automated proofs.  I mean by "proved by a computer" that an existing theorem was fully automatically proved by a computer().  I exclude verifications of existing theorems by a computer.  This is .


Can I have a link to the "ask as question" page with the tag field pre-filled?

We'd like to encourage people to ask questions on Stack Overflow. For this, we'd like to have on our site a link to the Stack Overflow , but we'd like to have the "tag" field pre-filled with a tag that would then help us find the questions. Is this possible?  Use case:   I work on an open source web forms product (Orbeon Forms), which implements the W3C XForms technology. On the web site for Orbeon Forms, we'd like to encourage people to ask XForms questions on Stack Overflow. As suggested by others here, this could be done by having somewhere on our site some HTML as follows: Have questions about XForms? Ask them on Stack Overflow.


I use Ubuntu 20.04.1, Gnome 3.36.3 on Lenovo ideapad L340 (UEFI, Dual boot with Win10) GeForce GTX 1650 with nvidia-driver-440 My desktop UI (top bar, popups, Applications screen) and login screen are twice larger that they should be. But all other applications work correctly. To fix this problem I tried:  To use open source driver - the problem is fixed, but I have very low performance with this driver.  To run with grub option acpi=off - the problem is fixed, but there's a lot of critical issues appears.  To set display scale to 200% and than revert - the problem is fixed until restart.  To reinstall Gnome with commands apt purge gnome-shell apt install gnome-shell ubuntu-gnome-desktop  nothing is changed at all.   Do you have any ideas how to fix this?


What is Closures/Lambda in PHP or Javascript in layman terms?

What are Closures/Lambda in PHP or JavaScript in layman terms? An Example would be great to aid my understanding. I am assumning Lambda and Closures are the same thing?


Compiling LaTeX document empties .bbl file

I'm trying out biblatex for the document I'm compiling, using the biber backend on my miktex distribution. Everything, including biber, should be up to date, assuming the MiKTeX repository currently holds the latest versions of everything.  This is what the biblatex documentation (p. 101) says about how often I have to run biber to update my .bbl file:     Whenever a reference to a work which has not been cited before is   added, this procedure must be repeated. This is also the case if the   last reference to a work which has been cited before is removed   because some citation labels may change in this case.   So if I make changes to my document (which is a very common activity in the process of writing a document), but leave the citations unchanged, I should not have to re-run biber before compiling the changes. However, every time I compile my document, regardless of the compiler or documentclass, the .bbl file is emptied. Consequently, the next time I compile the document without running biber, the bibliography is removed (seeing as the .bbl file contains nothing), and all my citations are broken. For this reason, I have to run biber before every time I compile the document, which largely counters the benefit of externalizing the bibliography in the first place.  How can I make the compilers stop overwriting my .bbl file and make everything behave as described in the biblatex manual?  Upon investigating the contents of the auxiliary files, I found that the .bbl file (after running biber, before compiling) begins with the following lines:  % $ biblatex auxiliary file $ % $ biblatex bbl format version 2.3 $   Does the biblatex version 2.8 still mark the .bbl files as version 2.3? If not, could this be the problem? And if so, why does my 2.8 version of biblatex (partly) behave as version 2.3?  Any help solving this problem would be much appreciated.


What are the assumptions of cross-validation if any?

are there any assumptions on cross-validation? For instance, is it necessary, that a) the test and training data are independent of each other? b) the distribution of the trainig data and test data is identical? If yes, I would be particularly interessted in literature about this topic. Thanks!


MacOS Big Sur - how do I disable/ skip verify on opening dmg

I have 2015 MBA running Catalina that at some stage in the past I managed to configure that when opening my own created dmg files (used for business data storage with encryption security) it no longer goes thru the verify process when opening - just straight to asking for the password. So I have bought a new MBA and installed Big Sur with clean install. Now I get the verify process each time I try to open my dmg files. Tried sudo defaults write com.apple.frameworks.diskimages skip-verify TRUE but it does not work. (In fact on my 2015 MBA, this flag is not set anyway). It is extremely time consuming to have to go thru the verify process every time I want to open (several) of my data dmg files. In response to a comment, I have set up a service as a work around that executes an automator service using shell script: hdiutil attach -noverify "$@" However, I find that I need to run the service twice in order to have the dmg file appear in finder - am I doing something wrong? Finally - are there any other alternate solutions - given diskimagemounter does NOT verify dmgs when opening in my MBA running Catalina.


I recieved an email saying that Windows XP's support is ending.  I have a computer with Windows XP and I want to know what are the risks on this computer that  (linked in the email) doesn't talk about.  I am aware they push for a Windows update or a computer change but this computer works well and I am not planning on changing it now or updating to Windows 7/8.  I use this computer for basic web search and mainly Word, Excel...  What should I do to protect my computer from "security threat" and what is this "security threat" exacly?    UPDATE   and  pointed out The email I am talking about most probaly is fake and not sent by Microsoft.  I am still in the unknown about what should I do to keep my computer as safe as possible


What is the most appropriate way to let my users know their data is taking a while to load?

For an application I'm working on, we have to make a call to a database where everything is tallied up and then displayed to the user. The problem presents itself in load time. Currently, it takes about 8 minutes to get all of the data collected, counted, and sorted which is WAY too long.  Other team members are working on speeding it up, however if it isn't possible because of the sheer amount of data, we'll have to show the user that their data is loading, it's just taking a long time and they can come back soon.  What is the best way to do this? Should text appear after a certain amount of time telling the user what is happening? Currently, we have a loading spinner that looks like the one below (converted to png for UX.SE), but is that sufficient? I feel like the user would think the application stalled.


Can drush delete individual nodes? And if so, can use drush to delete all nodes of a particular Content Type?   Background info: I'm not trying to delete the Content Type but all nodes of that type. Also this site is a dev install with a copy of a working database. I'm experimenting with feeds and imports and creating tons of nodes form RSS imports.


Is there a way to animate whether or not a particle emitter is emitting particles at a given point in time?  I'm using the particle system to animate bullets, so basically I'm trying to find a way to say: at frame 150 the gun fires a burst until frame 170, at frame 240 it fires a burst until frame 265, and so on.  I've tried key framing the particle render setting between "object" and "none", but the problem with that is that the hidden particles are still there, so when the render setting switches to "object", the particles that were initially hidden suddenly appear.  I've also thought of putting a plane (not rendered) with a collision modifier in front of the emitter and then moving it when I want the emitter to start emitting particles.  Is there a better way?


django and JavaScript form context, loading variables in JS

main.js is called in my template. Is the following syntax okay? Or is there another way? or do i have to name each element manually in JS  jQuery('#{{ form.use_acn.id_for_label|escapejs }}').click(function(){


Minimum Number of Values to Guess a Polynomial with Non-Negative Coefficients

My math teacher claimed that he could guess any polynomial with non-negative coefficients given two values that he asked for. For example, he asked me to write down a function of which I wrote down (x^5 + 3x^2) and didn't tell him. Simply by knowing the values of f(1) and f(5), he was able to guess the function with accuracy. Is this pure guessing or is there a mathematical explanation for it? Need to know a minimum of two values to guess a polynomial with non-negative coefficients.


How do I setup 301 redirects in Google Apps site?

I have just moved a website from a shared host to a Google Apps site.  Is there a way I can setup 301 redirects on my Google Apps site so that old links (with a different URL) can be 301 redirected to the new location on the new site?


Help understanding this schematic : Why is the diode there (AT89C2051 Programmer)?

I am having trouble understanding the following portion of schematic from AT89C2051 programmer circuit. Please help me comprehend what is going on here.   Here is what I understand:   A1 directly controls the 12V going to AT89_RST pin When A1 is low,    If A0 is high, AT89_RST pin sees high. if A0 is low, AT89_RST pin sees low.    So why is the 5V added there with the diode? I suspect it might be one of the following two reasons, but I really don't understand why.   To pull up AT89_RST to 5V. But A0 can be driven both high and low. Why pull it up? As some form of protection to prevent A0 from getting roasted with 12V? I think it might be the case, but I don't understand how it works to prevent that.   Notes:   AT89C2051 Programmer's . A0 and A1 are being driven by arduino (5V logic).


Does sickle cell anaemia protect a victim against malaria?

My biology textbook says that a person with sickle cell anaemia is less prone to malaria. Why is that so?  I'm guessing that its because the malarial parasite needs human RBCs for completing its life cycle. So are the sickle-shaped RBCs inhospitable to the parasite? In what way exactly?


Is there a searchable database of Linux commands? I'm new to the sport, and alot of information here assumes alot of knowledge I (and I'm sure many others) do not possess. However, I learn quickly, if I have a way to reference available commands.


Which journaling system best prevents torn writes like Windows NTFS?  I found this on "torn writes", but to be honest I do not understand the explanation.


I come from the Java world, where you can hide variables and functions and then run unit tests against them using reflection.  I have used nested functions to hide implementation details of my classes so that only the public API is visible.  I am trying to write unit tests against these nested functions to make sure that I don't break them as I develop.  I have tried calling one of the nested functions like:  def outer():     def inner():         pass  outer.inner()   which results in the error message:     AttributeError: 'function' object has no attribute 'inner'   Is there a way for me to write unit tests against these nested functions?  If not, is there a way to trigger the name munging for function names like you can for class variables by prefixing them with __?


How to prevent the switching of items inside the hotbar in vanilla minecraft [1.12.2]?

Is there a set of commands I could use which would allow for me to prevent a player from switching items? So if their "selectedItem" slot is 1, they can't switch the slot to 2.


Reputation chart in Opera has a display bug

Last item in the user reputation chart summary in Opera jumps to new line. I am using Opera Version 12.15 and Windows 7 64-bit operating system, zoom level is 100%.  See the screen shot:


What do 'real', 'user' and 'sys' mean in the output of time(1)?

$ time foo real        0m0.003s user        0m0.000s sys         0m0.004s $   What do 'real', 'user' and 'sys' mean in the output of time?  Which one is meaningful when benchmarking my app?


Suppressing addition of blank page before figure when wrapping long JPEG image

I have the following LaTeX file, whose sole purpose is to wrap a JPEG file. This file does not convert well to PDF, so I'm using this unorthodox technique to convert it.  \documentclass{article} \usepackage[pdftex]{graphicx} \pagenumbering{gobble} \begin{document}  \centering\includegraphics[height=650pt]{foo.jpg} \end{document}   This produces a PDF file including the document, but it first includes a blank page, and thus produces a 2 page document, rather than a 1 page document. How do I get rid of this blank page? Using \textheight instead of 650pt as an argument to \includegraphicsmakes the  problem go away, but I'd prefer the larger size I get from using 650pt.  Here is the relevant information from the log file.  <foo.jpg, id=1, 162.6075pt x 1165.35374pt> File: foo.jpg Graphic file (type jpg)  <use foo.jpg> Package pdftex.def Info: foo.jpg used on input line 14. (pdftex.def)             Requested size: 90.6998pt x 650.0pt.  [1  ] Overfull \vbox (100.0pt too high) has occurred while \output is active []   [2 <./foo.jpg>] (./foo.aux) )    I'd prefer to not make the actual document public. Therefore the code above is not a MWE. However, if anyone has tips on how to create a dummy JPEG of the same size, let me know.


Playing a DnD and our barbarian rushed into a room and stopped just through the doorway. Was surrounded by enemies. Dm said no allies behind barbarian would be able to get a attack because barbarian was blocking any attacks. The door size was just under a 5ft sq. Is this accurate? The map was tresendar manor area 10 north door .here is a picture of what I mean the orange is enemy blue is friendly


Alright so i have found  really good answer on how to normalize my data.   I implemented @user25658 's code into my own project successfully, trained a linear model and used it to make a prediction.   Say y = 0.4513869 is the predicted normalized value which i would like to de-normalize.  Based on the normalization code below, how can i achieve this?  normalized = (x-min(x))/(max(x)-min(x))


How to prevent the source code overflow over the frame in a listing?

I am trying to ident my source code in a frame using the listing package. An example code is given below:  \documentclass[article]{llncs}     \usepackage[english]{babel}     \usepackage[english]{varioref}     \usepackage[utf8]{inputenc}     \usepackage{graphicx}     \usepackage{color}     \usepackage[usenames,dvipsnames]{xcolor}     \usepackage{listings}     \lstset{basicstyle=\ttfamily\small\color{RoyalBlue}}     \usepackage{csquotes}     \usepackage{xcolor} \begin{document} \begin{lstlisting}[rulecolor=\color{black},frame=single,label={lst:dir},caption= example code that overflows the frame]  sssssssss sssss sssssssss ssssssssssss sssssssssssssssssssssssssss  \end{lstlisting} \end{document}   The problem is some part of the code(letter "s") overflows the frame. I would really appreciate it if someone can suggest any solution for this problem. Please note that I don't want to use linebreaks or any thing similar. In fact I don't want to disturb my code at any cost! Thank you!


Can an system (wind sail) move faster than the speed of the wind in the ground reference frame?

I just mean to be simple here, there are numerous articles on this platform itself regarding the exact topic and other information outside but I wanted to cover up the insight that I got here. After watching the video made by great youtuber derek (channel name:- veritasium) he covered a topic over this but somewhere in the second half he mentioned an important thing that the vehicle (so called blackbird) does not works like a windmill (that is the wheels help the movement of the flaps) and this niche change made him give an explanation. So I went ahead having a similar kind of theoretical machine in which instead of that arrangements the the flaps move the wheels and as just being a body with wheels it will move under the influence of wind getting a head start and after achieving certain velocity as the flaps are at an angle to the wind they will move fast thus making a non electrical machine move faster than wind by which it is propelled. ( As a system can move faster at an angle and as the flaps are at an certain angle they move faster than the wind and thus blowing away the particles of air behind to get acceleration). I still do not feel any good about this, I do feel that a machine like this will just not be possible or would even convert that heat in heat energy not to cross that limit. I don't understand that why it isn't possible. I feel like making absurd mistake. Link to the video,


i recently bought a new PC and i had no Windows available (my stick broke, had to buy a new one). So i just used a 4 GB Stick to install Ubuntu. Now i though i just can install Windows like normally but i cant event get the windows Iso on my Stick. I used WinUSB and it just stucks at installing for i386-pc some thing some thing. Also i tried using the Methos where i copy the iso files onto the stick, that didnt work either because even tho i changed the boot priority and safe mode + UEFI Boot it still booted to Linux instead of the Windows Installation Programm. My Question now is: How do i install Windows and Remove Linux (Ubuntu)? If possible a Version that is very easy! Iam not very technical. I dont want to Dual Boot or something like that, just want to get rid of Ubuntu and install Windows.  Hope you can Help me.  edit. I do not have a CD nor a Drive for one.


Palindrome using args; help me find the error?

I am building a class that checks if the input contains palindromes and returns only the palindrome terms if they exist. I have been able to develop the following, and it compiles and runs without errors, but I am not getting any return from it.  Can anyone spot where my error lies?  public class Palindrome {  public static boolean isPalindrome(String word) {      String back = word.charAt(word.length() - 1) + "";     for (int i = word.length() - 2; i >= 0; i--) {         back = back + word.charAt(i);     }     if (word == back) {         return true;     }     return false; }   public static void main(String[] args) {     for (int i = 0; i < args.length; i++) {         if (isPalindrome(args[i]) == true) {             System.out.println(args[i]);         }     }  }  }   I believe the issue lies in the main method, specifically within the if statement, but I'm not exactly sure why it's not working.  public static void main(String[] args) {     for (int i = 0; i < args.length; i++) {         if (isPalindrome(args[i]) == true) {             System.out.println(args[i]);         }     }  }   Thank you in advance for any help offered. I appreciate your time!


test for convergence $\sum_{n=1}^{\infty} \frac{1}{n^n}$

Test for convergence  $$\sum_{n=1}^{\infty} \frac{1}{n^n}$$  I'm at a loss on what to do, is this a geometric series $\frac{1^n}{n^n}$?


Simple question, has anybody ever seen a similar visualization to the one below? If so what is the name of such a graph and what software could be used to create it?


Do I have to count a book as my single DDAL-legal additional source to use a spell from it?

In Adventurer's League, you can use the Core PHB and one additional source to create your character.  This is clearly stated applying to races and sub-classes (so you can't have a Purple Dragon Knight Goliath, because two separate books), but does it apply to Spells?  Specifically, If I build a High Elf Fighter, and I choose Green Flame Blade as my High Elf cantrip, am I locked into using Sword Coast Adventurer's Guide as my single additional source?


MySQLHow to select records without duplicate

Table Name: Order  Columns: ID & NAME & DATE  With the following records :  1 | starone | 2016 1 | starone | 2016 2 | mogaone | 2017 9 | starone | 2016      And am looking to only select data without getting duplicates :   Expected OUTPUT  1 | starone | 2016 2 | mogaone | 2017 9 | starone | 2016   So which query shall i use?


How to type latin small letter c with cedilla

I run Ubuntu on a DELL XPS 13 notebook that has an US keyboard configured as US international. After upgrading to version 13.10 I can no loger get a cedilla by typing '+C. Instead, I get a "ć".  What should I do to get a "ç"?  I am using Ubuntu Gnome 13.10 64 bit.