I've installed Helvetica Neue fonts on my Windows. The problem is when websites use Helvetica or Helvetica Neue typeface, they almost exclusively do it simply using "Helvetica" or "Helvetica Neue" font-family. But In my windows, the Helvetica fonts are installed as a "HelveticaNeueLT Com 45 Lt" or "Helvetica LT Std" or similar extended name. I've tried to create my test page, and the browser renders the font properly only if I use the full font name. I'd like to know, how to make windows/browser display Helvetica properly?


I'm trying to install Ubuntu on an old HP Pavilion zd7000. It has a Pentium 4 | 2.8GHz | only 512 of RAM. The installation appeared to work fine, I can boot to a login screen but after entering my credentials it goes to a black screen with the mouse and completely unresponsive.  The video card is an old nVidia with 64MB of memory.  I suspect that it might be a driver issue but I'm relatively new to Ubuntu, so I'm asking the questions.  Thank you all for your time and attention with this matter it is appreciated.


Do physicists accept true randomness in nature?

I am not a physicist but I've started studying the subject and noticed that terms like "random", "randomness", "randomly" are widely used when talking about nature. For example, random movement of atoms, random fluctuations, random path of an electron etc.  My question does not concern any of these examples themselves.   What I would like to know is whether physicists use the term "randomness":  A) Literally   That is, whether physicists believe that true randomness actually exists in nature: Do physicists believe that (in some cases) something that is in a certain state X, is so not due to some cause (or a collection of causes) that preceded it and caused it to be in that particular state X rather than in some other possible state Y. In other words do physicists believe that causality is not a rule.  or   B) Figuratively   Do physicists use the term "randomness" as simply a shorter way of saying:  "we know that there must be a trillion things that caused this state X rather than this other possible state Y, but because the number of things that constitute that cause is so great, we can never know it or grasp it in its whole as humans, so in those cases we'll call it 'random' for lack of a better word, but we don't actually mean 'random' in the literal sense of the word".  ?  EDIT: I want to know how the term is used by physicists, so that I may know how to proceed with the study of the subject. I'm not interested in opening a discussion about whether nature actually is (or not) non-deterministic sometimes.


To start with I will say that none of the supposed 'answers' for this here & elsewhere have worked for me (referring to this:  )  In what follows I am referring to an old PC of mine that has Ubuntu 17.04 + Mate on it at the moment.  This system is not meant to be permanent - and some operations are simply not succeeding because I NEED to be the root user - not getting the job done with sudo, not nohow that I have been able to find.  Please - no scoldings or lectures about the dangers of this choice. (Yes, I know this is dangerous, etc.,etc.,etc...) On this system that is irrelevant as it will be replaced with other distros quite soon as it is just a 'play' machine with zero data on it of any importance.  Used to be this was not such a big deal & I've done it before on earlier versions - but 17.04 is fighting me on this & I am really stuck.  After making a few mods I can choose to log in as either of the 2 users shown when it boots - but cannot enter a username in LightDM. After logging in, I can also do su -, enter the password & get to # in terminal, but this is not the desired goal here and also not getting the job done.  How can I fully unlock (& de-obfuscate) the user & group root to allow a full GUI log in as root?!?  (Also, if anyone will affirm what steps accomplish the same goal for 16.04 that would be helpful as well because I will soon be using that version with Mate on the same old PC??)  (The info posted based upon Unity didn't work on my system with MATE...)  Thanks for any helpful replies!!


Run Multiple Scripts In One Transaction Across Multiple Servers

We have deployment scripts that we need to run on databases that are spread across multiple servers. One script only runs on one database, but the scripts depend on each other. We are looking for a way to run all of the scripts as one big transaction so that all scripts either commit or rollback as a whole.  How do I do this?  I would prefer a way to do this from ADO.NET, but SSMS is cool, too.  My current solution (that does not work) is that I begin transaction in every database, run all my scripts, and then commit/rollback once everything is good. However, I can't run all my scripts since cross-database dependencies are blocking indefinitely.


Null pointer exception at preparedStatement

I am designing simple bank application using servlet and jdbc  so while inserting data into database I am getting null pointer exception at preparedStatement  my code for that is   Connection con=null;      PreparedStatement preparedStatement =null;       try      {      con = DBConnection.createConnection();      String query = "insert into cst_details(name,surname,aadhar_no,contact_no,address,balance) "             + "values (?,?,?,?,?,?)";      preparedStatement = con.prepareStatement(query);      preparedStatement.setString(1, name);      preparedStatement.setString(2, surname);      preparedStatement.setString(3, aadhar_no);      preparedStatement.setString(4, contact_no);      preparedStatement.setString(5, address);      preparedStatement.setString(6,initial_bal);


Creating an email that can trigger a script

I have a CentOS 6.3 server. I would like to create an email address like, for example, list@myserver.com that will be a special kind of email that will trigger a script.   For example: suppose I mail list@myserver.com and the subject is an IP address. I want the server to receive that mail, extract that IP from the subject and append it to a file.  How is this done on Linux? Can you guys tell me how this can be done?


query to select data between todays date as well as tomorrows date time upto specific time

I have database "raj" with table "pagination"  In table pagination have "id", "actualtime" and "created" field  id - auto_increment name- varchar created- datetime   I want to display all rows which is created on todays date display upto yesterdays 06:00 pm.after that the content will be refreshed based on based on a DATETIME field called 'created' that holds the date and time of each record's creation.  this is my query to fetch rows but it is not working properly...plz help me......  $sql = "     SELECT name      FROM pagination where created >= DATE_SUB(CURRENT_DATE(),INTERVAL 1 DAY)        ";


Find $\lim _{x\to 1}\left(\frac{x^n-1}{x^m-1}\right)$

So I do know how to find the answer n/m, using l'hopital's rule, but how to find it without using that rule?  $\lim _{x\to 1}\left(\frac{x^n-1}{x^m-1}\right)=\frac{n}{m}$


If I end a sentence with initials do I add a second period?

If a sentence has someone's initials as the last word, do I add a second period?  Example:  And that was the last they saw of T.J.  or  And that was the last they saw of T.J..


How to create your own Linux package from scratch?

How do you create your own package in Linux, just like cd, ls, or any third party package? All I know is how to create a .sh file, write a script in it and execute it using: bash file_name  But in addition to that I want to understand in more depth. Please explain the complete steps from downloading using apt-get to how to run it.


How do I connect 16 SATA-drives to one Adaptec ASR-6805 KIT? (2 SFF-8087 Internal Ports)

Kit includes only 2 cords SFF-8087 to 4xSATA... Sum is 8. I need 16. What should I do? No way to change the controller. But can buy additional cards or wires if needed. Please advise.


I'll do my best to describe it; a kind of faded out look, the focus seems right but still the image looks like it was shot in light fog. Is there a name for "that look" and how is it usually achieved?   and   Page with more  (have no connections to neither the author nor anything, just like the page and would like to try to accomplish that effect myself).


Proof of a combinatorial identity: $\sum\limits_{i=0}^n {2i \choose i}{2(n-i)\choose n-i} = 4^n$

Possible Duplicate:          This was part of a homework assignment that I had, and I couldn't figure it out. Now it is bugging me. Can anyone help me? Although a proof would be nice, I wouldn't mind a push in the right direction.   $\displaystyle\sum_{i=0}^n {2i \choose i}{2(n-i)\choose n-i} = 4^n$


I have an Apache server running on a Raspberry P and it works just fine in the local network. And after forwarding port 80 and trying to connect using the public IP, Chrome says ERR_CONNECTION_REFUSED. But the strange thing is that I CAN reach the server when using VPN and using the same IP. What can I do?     -telnet 80.***.***.78 80      Trying 80.***.***.78...     telnet: connect to address 80.***.***.78: Connection refused     telnet: Unable to connect to remote host     -route -n      Destination     Gateway         Genmask         Flags Metric Ref    Use Iface     0.0.0.0         192.168.0.1     0.0.0.0         UG    0      0        0 eth0     192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0      -sudo netstat -lapute:              Active Internet connections (servers and established)     Proto Recv-Q Send-Q Local Address           Foreign Address         State       User       Inode       PID/Program name     tcp        0      0 *:http                  *:*                     LISTEN      root       6137        2051/apache2     tcp        0      0 *:ssh                   *:*                     LISTEN      root       6367        2249/sshd     tcp        0      0 pi.local:ssh            nmb.local:65535         ESTABLISHED root       8669        2565/sshd: pi [priv     udp        0      0 *:9949                  *:*                                 root       5918        1809/dhclient     udp        0      0 *:mdns                  *:*                                 avahi      6293        2184/avahi-daemon:     udp        0      0 *:54070                 *:*                                 avahi      6295        2184/avahi-daemon:     udp        0      0 *:bootpc                *:*                                 root       5946        1809/dhclient     udp        0      0 pi.local:ntp            *:*                                 root       6310        2200/ntpd     udp        0      0 localhost:ntp           *:*                                 root       6309        2200/ntpd     udp        0      0 *:ntp                   *:*                                 root       6304        2200/ntpd


How do I use ClamAV to scan my entire computer?

How do I use ClamAV to scan the entire computer? Im on Ubuntu 16.


If I SSH into another machine from my macbook, start compiling a very large project, and then power off my macbook, will the compiling continue on the remote machine despite having lost connection to my macbook?


How to create a shell script to create a folder by using the today's date to take backup using rsync command on every evening around 7 pm

1] I want to create a script which matches the today's date >> with server's date format.  2] If it matches then, it will create the folder named "$date" itself in the mentioned path "/tmp/test/files/testing/".  3] Moreover, it will search for the files which are created by today's date with the help of "find" command from "/var/www/path" and take the back up with the help of the rsync command of those files into /mnt/ folder.  I'm kinda new shell scripter however, kindly help me with the script.  ________________________________________________________________________________  What I've did until now is :>>>>>>>  ##!/bin/bash  now=$(date +"%m_%d_%Y")   mkdir /tmp/test/files/testing/"date +%b%Y%m%d"/$now &&   find . -type f -newermt 2019-06-10 -ls -exec rsync -avzh {} /mnt/Data/exes/10-June-2019/ \;  &&  mysqldump -h localhost -u username -ppassword production > /mnt/Data/date +%b%Y%m%d/productionDate.sql   ________________________________________________________________________________  Thanks, Bakula


How to deal with that type of question ?  Are there infinite prime numbers beginning by 2?  I know that there infinite prime ending by 1,3,7 and 9 by Dirichlet’s prime number theorem.   I’am only interested by the first term in special case 2. Not for a generalization. I think that this specific case provide a simpler proof than the generalization.


How to create a working windows xp usb stick in Ubuntu14.04? & how to dual boot with it

Hello,My dear friends.I need your help. I have windows xp iso file in my pc .I want to create a bootable usb stick for it and install windows xp along with Ubuntu ,but I don't know how.winusb software not working with windows xp.please help meeee.


I've just learned how to insert pictures using the \includegraphics{} command. In the compiled PDF document, the file name is visible immediately below the image.   Is there a way to suppress the file name? (see the red arrows below)


Can I use copyrighted sprites for a demo?

I just had a quick question and wanted everyone's opinions.  I'm making a 2D demo game for a resume which I want to post online. I'm applying as a programmer position so I don't really have my own art. I am planning on using sprite sheets and tile sets from other games in order to create just one or two levels on my demo. I will give credit at the bottom of the screen and state that these sprites are not my own.  Is this a good idea or could this be potentially "dangerous" in the illegal sense?


Does not compile with complete text but, when I compile it separately, it gives me the required output. What should I do?

\begin{eqnarray*} M&=& \max{\left \{a,b,\frac{a+b}{2},\right}\\ && a+b,a+b/2\Bigg\} \end{eqnarray*}


Getting null point exception on invoking location in Android N.

I am trying to build an app that gets the current location of the device. But it throws nullPointException on:- lat.setText(location.getLatitude()+""); as location object is always null. Please resolve this issue the following code is tested in Android-7.1.1    package in.technomenia.user.test;  import android.Manifest; import android.content.Context; import android.content.Intent; import android.content.pm.PackageManager; import android.location.Location; import android.location.LocationManager; import android.os.Build; import android.support.annotation.NonNull; import android.support.v4.app.ActivityCompat; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.TextView; import android.widget.Toast;  public class MainActivity extends AppCompatActivity {      LocationManager locationManager;     Location location;     TextView lat, lng;     Button getlocation;     private boolean permission_granted = false;      @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);          lat = (TextView) findViewById(R.id.lati);         lng = (TextView) findViewById(R.id.longi);         getlocation = (Button) findViewById(R.id.get_latlng);           locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);         locations();      }      public void locations() {         Toast.makeText(getApplicationContext(), "permissions-> "+permission_granted, Toast.LENGTH_SHORT).show();            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {                 if (ActivityCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED){                     if (permission_granted == false) {                         requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 19);                         Toast.makeText(getApplicationContext(), "Requires GPS Permission", Toast.LENGTH_SHORT).show();                     }else{                         if(locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER) || locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER))                             location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);                         else                             Toast.makeText(getApplicationContext(), "Enable Locaion", Toast.LENGTH_SHORT).show();                     }                 }              } else {                 permission_granted= true;                 Toast.makeText(getApplicationContext(), "less than android m", Toast.LENGTH_SHORT).show();              }            getlocation.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                    if (permission_granted == true) {                     Toast.makeText(getApplicationContext(), "permission granted", Toast.LENGTH_SHORT).show();                     lat.setText(location.getLatitude()+"");                     lng.setText(location.getLongitude()+"");                 }              }         });      }         @Override     public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {         super.onRequestPermissionsResult(requestCode, permissions, grantResults);         if(requestCode ==19){             if(grantResults[0] == PackageManager.PERMISSION_GRANTED){                 permission_granted = true;                 locations();              }else{                 permission_granted= false;              }         }     } }


I am a graphic designer and I wanna buy a Pantone colour guide book, the pair one for coated and uncoated colours which compares the Pantone color with its CMYK version?Any advise which pait is the best? Thanks!


How do I add more categories to Mac OS X Finder's sidebar?

My Finder sidebar has two categories: Favorites and Devices. How do I add more categories?


Restoring iOS without updating iOS in iTunes

I have this problem that when I'm trying to restore my iPhone 6 on iTunes it keeps me prompting me that restore and update when I'm just choose the restore option only, cause I don't want it to update its own iOS to the newer one. Is there a way to avoid updating when I choose the restore option only? I already search all the solution online yet no answer help my concern.


Schengen Visa: Itinerary change after visa issued

I am an Indian passport holder got my schengen Business visa approved from Belgian consulate. At the time of applying visa, i have produced my travel itenary as, Norway (1N) --> Belgium (14N)   now due to some reason I have to reschedule it and will be like: Norway: 1N Finland: 2N Sweden: 4N Belgium: 8N  Can somebody guide me if this is OK? or do i have to follow some procedure?


I've upgraded my desktop computer from Windows 7 to Windows 10 long time back. So initially I had Windows 7 Pro license. Now I need to re-install Windows10 on the same desktop computer. Question - do I need to go through Windows 7 -> Windows 10 upgrade chain or I can directly install Windows 10? If last, would it accept Windows 7 serial or it will recognize my computer/license when I sign in to my Microsoft account?


Is it possible to give an estimation (maybe an approximation) of the size of the $k$-th prime number?


Are $\mathbb{C}$ under addition and $\mathbb{C}$ under multiplication isomorphic?

Is it true that $\mathbb{C}$ under addition and $\mathbb{C}^*$ under multiplication isomorphic?   I don't think we can use the argument that,  $\mathbb{C}$ have zero inside it, but,  $\mathbb{C}^*$ don't have. As, they are infinite sets anything can happen.   I have proved that, $(\mathbb{R},+)$ and $(\mathbb{R}^+,\cdot)$ are isomorphic using the map $x\mapsto e^x$. Can I use that? I can't see how that map will work here.  Can anyone please explain hoe to proceed? Any hint will be appreciated.


Why isn't the acceleration at the top point of a ball’s journey zero?

When I shoot a ball vertically upward, its velocity is decreasing since  there is a downward acceleration of about $9.8\,\mathrm{ms}^{-2}$.   I have read that at the top most point, when $v = 0$, the acceleration is still $9.8\,\mathrm{ms}^{-2}$ in the downward direction where $v=0$. That is, the acceleration is still the same.  But at the highest point, the ball is stationary, so it is not even moving. How can it accelerate?


Let $S$ be de pseudo circle (see for instance ).  How can I compute its higher homotopy groups?  The question came up while trying construct a weak homotopy equivalence $X\to Y$ that does not admit an inverse. Taking $X=S^1$, $Y=S$ and $f$ as in the wikipedia page should work, but I was not able to work out a "simple" way of calculating $\pi_n(S)$ for $n>1$. By "simple" I mean that it should not invoke a generalization of that I am trying to prove.


Creating duplicate features based on many-to-one conversion of related table?

I need to create duplicate features (in this case parcels), using a related table to populate ID fields.  In essence, I need to use a related table of parcel owners to create duplicate parcels, each with its own unique ID from the related owner table.  The related table already contains the many-to-one link to parcels, I just want to force a one-to-one relationship between the owners and parcels, by creating a duplicate parcel for each owner record.  I'm using ArcGIS Desktop 9.3.1.


When i click on confirmation email after entering all details on evisa.gov.tr it says "Unfortunately, we are not able to issue e-Visa for you."Yesterday it was working perfectly and payment page loaded without any issue but due to some reasons i haven't paid. Should i wait for 48 hours and try my luck again. I have valid UK visitor visa.


Trying to prove (A ∩ B) - C = (A - C) ∩ (B - C)

Trying to prove $(A ∩ B) - C = (A - C) ∩ (B - C)$ Im stuck here on this problem:  $(A ∩ B) - C = \{x\mid x \in (A ∩ B) ∧ x \not\in C\}$  $(A ∩ B) - C = \{x\mid(x ∈ A ∧ x ∈ B) ∧ x ∉ C\}$  $(A ∩ B) - C = \{x\mid(x ∈ A ∧ x ∉ C) \lor (x ∈ B ∧ x ∉ C\}$  I'm stuck right about here because how do I change the or ($\wedge$) sign to the intersection sign ($\cap$).  Edit: step 3, changed the and to an or


Let $$ A:=\left[\begin{array}{llll} 3 & 1 & 0 & 0 \\ 1 & 3 & 0 & 0 \\ 0 & 0 & 6 & 2 \\ 0 & 0 & 2 & 6 \end{array}\right] $$ Find $\sup _\limits{Q \in M_{4\times 2} (\mathbb{R}), Q^{T} Q=I_{2}} \operatorname{tr}\left(Q^{T} A Q\right)$, where $M_{4 \times 2}(\mathbb{R})$ represents the set of all matrices of size $4\times 2$. I know that $\mathrm{tr}A=\sum _i A_{ii}$, but how can we deal with this upper bound? It is obvious that $Q^T AQ$ is a $2\times 2$ matrix, but I don't know how does the condition $Q^TQ=I_2$ help. Also, are there any backgrounds for this problem? I seldom see (linear algebra) problems asking the uppper bound for a trace and I hope I could get further information about these kind of problems (if possible).


How to prove that Normal Squared Distances follow a Chi-Square distribution?

Given a multivariate normal distribution  $f(x) = \frac{1}{\sqrt{(2 \pi)^n|\Sigma|}} \times \exp\left( -\frac{1}{2} (x-\mu)' \Sigma^{-1} (x-\mu)\right)$  how can I prove that $ (x-\mu)' \Sigma^{-1} (x-\mu) \sim \chi^2_{p} $?


Why the radial delta function is not equal to the product of two 1D delta functions

The first proof that comes to my mind is that the units of left side and right side does not match. Delta functions take an input and spit out an output of units = 1/[units of input]. What would be the rigorous proof of this?  $$\delta \left ( r \right )\space \space  \neq \space \space \delta \left ( x \right )\delta \left ( y \right )$$


Why do we have vector spaces over a **field**?

A vector space is defined as a set $V$ together with a field $F$, such that $(V,+)$ is an abelian group, and $V$ has scalar multiplication that is compatible with $+$. But why is it that in this definition, we require $F$ to be a field, and not any commutative ring?  To illustrate, consider $V=\mathbb Z^n$, the set of all $n$ dimensional vectors with integer coordinates. Why doesn't it make sense to extend the definition of vector spaces such that we can say $V$ is a vector space over $\mathbb Z$? All the familiar properties remain: we certainly have closure under scalar multiplication, and the other axioms remain. In particular, the axioms say nothing about needing to have inverses, which is the only thing fields add on top of being a commutative ring. So why wouldn't ordinary commutative rings suffice?


Is the .iso file the one I need to download?

I want to install Linux Ubuntu for Virtual Box, but is the .iso file the correct one for it, or will it just set up as another base operating system directly? Any help would be greatly appreciated.


Column line overshooting the horizontal line in table

\begin{tabular}{|m{3.5cm}|m{5.5cm}|m{4.5cm}|} \hline \emph{Category of Benefits} & \emph{General Benefit} & \emph{Operational Advantages} \\ \hline \multirow{3}{*}{\pbox{3.5cm}{Robust operational performance}} & \multirow{3}{*}{\pbox{5.5cm}{One sensor can contribute information while other are unavailable, denied(jammed), or lack coverage of a target or event}} & -Allows continued operation despite jamming \\ &  & -Graceful degradation \\ &  & -Increased probability of detection \\ \hline  \multirow{2}{*}{\pbox{3.5cm}{Extended spatial coverage}} & \multirow{2}{*}{\pbox{5.5cm}{One sensor can look where another cannot}} & -Increased survivability \\ &  & -Probability of detection increased  \\ \hline \label{tab1.1} \end{tabular}   For the LateX code mentioned above the table which comes looks like this ![enter image description here][1]   In the resulting table, column 1 vertical line overshoots the last horizontal line.  What is the problem?


Ubuntu-desktop (file, edit, help, etc...) missing from panel after unity --reset

After running unity --reset to fix a Compiz plug-ins problem, the dropdown menus (file, edit, help, etc...) that normally appear on the left end of the menu bar when the desktop is in focus are missing.  Any suggestions as to how I can correct this? I am running version 12.04.


Apologies if this question has already been answered somewhere already.   Is there somewhere I can view a list of tags which have been burninated/blacklisted from certain sites?  UPDATE:  I'm building a script which tags documents with relevant Stackoverflow tags. I was seeking a way of excluding at least some meta/unhelpful/ambiguous tags from my corpus of tags, to get rid of some noise in my data. Shadow Wizard's suggestion basically provides what I need.


Prove inequality of binomial theorem $\frac1{n^i}\binom{n}i \leq\frac1{m^i}\binom{m}i $.

I have to prove the following inequality:     $$\forall n,m \in \mathbb{N},i\in\mathbb{N_0}:n<m \implies \frac1{n^i}\binom{n}i \leq\frac1{m^i}\binom{m}i $$   I used this fact to prove an other inequality, without proving this one first, but now I am stuck. Is induction the way to do this?


When is use this code  \documentclass{amsart}  \usepackage{calligra,lipsum} \usepackage[T1]{fontenc}  \DeclareRobustCommand{\normalfont}{\calligra} \AtBeginDocument{\normalfont}  \title{A title} \author{An author}  \begin{document}  \maketitle  \section{A section} \lipsum[1]  \end{document}   everything goes fine, but when i try   \documentclass{book} \usepackage{titlesec} \usepackage{titling} \usepackage{xunicode} \usepackage{fontspec} \usepackage{xltxtra} \usepackage[T1]{fontenc}  \newfontfamily\headingfont[]{Calligra} \titleformat{\chapter}[display]   {\huge\headingfont}{\chaptertitlename\ \thechapter}{20pt}{\Huge} \titleformat*{\section}{\LARGE\headingfont} \titleformat*{\subsection}{\Large\headingfont} \renewcommand{\maketitlehooka}{\headingfont}  \begin{document}  \chapter{First Chapter}  The title above does not show any font.  \end{document}    I get fontspec error: "font-not-found" The font "Calligra" cannot be found. I am using XeLaTex.


Which performance measure to use when using SVM: MSE or MAE?

It is a common practice to measure an SVM model's performance by calculating its MSE (Mean Square Error). Why not use Mean Absolute Error (averaging errors' absolute values instead of squared values)?


Does the rotation of the earth affect the travel time from Europe to Australia?

Assuming that a place in Europe is exactly on the opposite side of the earth than Sydney. Now I want to take a plane to travel there. Does it matter if the plan flies with the rotation of the earth or counter the rotation of the earth? i.e. Does it matter if the plane flies westbound or eastbound?  Intuitively I would say it does matter, because if I fly against the earth rotation the goal, in this case Sydney is coming nearer. On the other hand, maybe the plane is still in the atmosphere and therefore part of the earth rotation.


I have gone through the intial steps and downloaded the files to a USB drive.  I have setup my computer to boot to USB.  When I try to do install and run the file I'm using the Boot from CD.  I restart and it's still not trying to boot to the drive.  I've even tried to just unpack and install to the stick, but it says it doesn't have enough space.  The stick is a 64 GB stick.


I have a question which is based on the question . The question reads:     Show that if A is compact, show that $d(x,A)= d(x,a)$ for some $a \in A$.   What if I change the question to     Show that if X is complete and $A \subset X$ is closed, show that $d(x,A)= d(x,a)$ for some $a \in A$.   I'm at a lost here. Can I get a hint? I can't seem to use to hints at the original post. My initial thoughts are to construct a sequence such that it converges to $inf\{d(x,a) | a \in A\}$. However, I need to show that the set $\{d(x,a)|a \in A\}$ contains its $inf$. I'm not sure how to proceed.


i just received an email saying Your UK visa application has been concluded, does this mean that visa has been refused?


How to transfer at Dubai between Terminals 2 and 3 with luggage?

I'm arriving in Dubai at Terminal 2 with flydubai and my flight with Emirates leaves from Terminal 3. As they are separate bookings, I realise I have to collect my luggage and clear Customs and Passport Control etc.  How do I transfer from Terminal 2 to Terminal 3 with luggage?  Is a taxi the best way, or is there a bus?


Ubuntu 12.04 LTS server - build-essential install not possible

Have found this question multiple times on the forum, but none of the answers were serious enough. So the problem with ubuntu 12.04. LTS server is that after a fresh install you can not install build-essential package. This is what you get:   Reading package lists... Building dependency tree... Reading state information... Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  build-essential : Depends: libc6-dev but it is not going to be installed or                             libc-dev                    Depends: g++ (>= 4:4.4.3) but it is not going to be installed   Things that DON'T help:   apt-get clean apt-get update apt-get -f install apt-get upgrade dpkg --configure -a apt-get autoclean apt-get --fix-missing install build-essential   apt does say that I have "held broken packages", but none of the above commands solves them. After running any of the above commands the summary at the bottom is all zeros (upgraded, newly installed, remove, not upgraded)  uname -a gives:  Linux sorrg01lin 3.11.0-15-generic #25~precise1-Ubuntu SMP Thu Jan 30 17:42:40 UTC 2014 i686 i686 i386 GNU/Linux   lsb_release -a gives:   Distributor ID: Ubuntu Description:    Ubuntu 12.04.4 LTS Release:    12.04 Codename:   precise


Converting the power series from sigma notation to a function?

The sigma notation for the power series is equivalent to the following function: $$\sum_{n=0}^\infty x^n = \frac{1}{1-x}$$  However, given the sigma notation above,  how would one arrive at it's equivalent function?


Large Fonts Are Not Consistent in Stack Exchange iOS App

Self explanatory on picture  App Version: 1.6.6.2 Device: Unknown (iPhone10,4) OS Version: Version 13.6.1 (Build 17G80)


An example of a non Noetherian UFD.     I know an example is $$K[x_1,\ldots,x_n,\dots]$$ with $K$ a field, but I don't know why. Can someone give another example or better an explanation?   Is it not Noetherian because it's not finitely generated? And why do you know it is a UFD?? My question now is how to prove this is a UFD.


Can someone explain the use of foor->bar when calling a function?

Is it different from foo.bar calling a function from a specific instance? I've seen it around on tutorials but it's never explained and it's too general a term to show up on google.


Cancellation for finitely generated abelian groups

Let $A,B,C$ be finitely generated abelian groups. I want to show that $$A\oplus C \cong B \oplus C $$ then $A \cong B$. My idea is as follows: we begin by noting that this has already been proved for $A,B,C$ finite. Let   $A = \mathbb{Z}^{k_1}\oplus A'$   $B = \mathbb{Z}^{k_2}\oplus B'$  $C = \mathbb{Z}^{k_3}\oplus C'$  Then we have $$\mathbb{Z}^{k_1+k_3}\oplus A'\oplus C' \cong \mathbb{Z}^{k_2+k_3}\oplus B'\oplus C'$$ Therefore $k_1 = k_2$ and then I would like to divide out by the infinitary parts to get $$A'\oplus C'\cong B'\oplus C'$$ and since all groups are finite we can use previous theorems to derive $A'\cong B'$ hence $A\cong B$. However I am not sure how to get past the 'dividing bit' as to assume that we can cancel would be circular. How should I proceed? Is the assumption that finitely generated abelian groups cancel even true?


Elementary number Theory / squarefree numbers

Can you help me to prove "Show that for any square-free integer $n > 1, \sqrt{n}$ is an irrational number."?   I'm asked to show that any square-free number $n, n^{\frac{1}{2}}$ is irrational.   I applied proof by contradiction here and assumed $n^{\frac{1}{2}}$ is a rational number. Therefore $n^{\frac{1}{2}}$ is equal to, lets say, $\frac{a}{b}$ where a and b are natural numbers.  Since $b^{2} \times  n = a^{2}$, I know that $n$ must contain a square number but I cannot prove it yet. I hope you can help me.


Print special characters like "à" from MySQL in PHP

I have a database, utf8_general_ci, and I have manually inserted the values into. Between those values, I have also special characters like à, è and so on. Now what I'm trying to do, is to print those values through PHP. My page has already <meta charset="utf-8"> , also $mysqli->real_escape_string but I still get a ? instead of that characters. Is not a font problem, if I manually echo "à"; it works, but the data from DB doesn't.


I was reading Schutz, A First Course in General Relativity. On page 9, he argued that the metric tensor is symmetric:     $$ ds^2~=~\sum_{\alpha,\beta}\eta_{\alpha\beta} ~dx^{\alpha}~dx^{\beta} $$   $\text{Note that we can suppose}$ $\eta_{\alpha\beta}=\eta_{\beta\alpha}$ $\text{for all}$ $\alpha$ $\text{and}$ $\beta$ $\text{since only the sum}$ $\eta_{\alpha\beta}+\eta_{\beta\alpha}$ $\text{ever appears in the above equation when}$ $\alpha\neq\beta$.   I don't understand his argument. If someone can explain why, I would really appreciate it.


Rotational kinetic energy when moment of inertia is changed

The following quote comes from:      Consider an ice skater that has just gone into a spin with arms   stretched out.  If it helps, the skater is wearing lead bracelets on   each wrist.  As the skater spins, the angular momentum and angular   kinetic energy are constant;  friction with the air and with the ice   can be eliminated.  The skater must exert an inward centripetal force   on the bracelets to keep them rotating in the same circle, but this   force does no work, since the bracelets are not changing their radius   of rotation.      Then the skater pulls in his arms and the bracelets, closer to his   axis of rotation.      Several interrelated things happen:           since there is no external torque, the angular momentum of the system stays the same;   Since the various masses of the skater are all moving towards the axis of rotation, the total moment of inertia of the system   decreases;     Combining 1 and 2, the angular velocity of the system increases;  if the moment is halved, the angular velocity doubles   Combining 2 and 3, with some quantitative treatment, the angular kinetic energy increases;  if the moment is halved and the   angular velocity is doubled, the kinetic energy doubles;   The skater does work;  his arms are now exerting an inward force through a distance as his arms draw the bracelets inward;  the work done can be rigorously shown to be identical to the increase in   kinetic energy...      However, it only covers a case when work is done to pull arms inwards. It is understandable that the work would be done in such case.  But what is happening in the opposite case when the skater has their arms inwards and lets them go outwards? S/he doesn't do any work but kinetic energy (and total energy) is lost. Why is it lost?  E.g.  I = 2kg * (1m)^2 w = 3.14/s L = 2kg * m^2 * 3.14/s Ek = 9.869  After shifting 2kg by 0.1m outwards: I = 2kg * (1.1m)^2 = 2.42 kg * m^2 L = 2 * 3.14 = 2.42 * w w = 2.5963 Ek = 8.1566   So, where did 1.7124 J go?  The quoted answer describes the easy case and omits the hard one.


I'm the owner of iPhone 4. Is there any possible way to downgrade from 7.02 to one of the previous firmware versions? The whole point is I don't have and have never had SHSH blobs and have never jailbroken my phone. The ideal is to get back to iOS 4, but even 5 and 6 would be fast enough for not annoying me all the time with iOS 7's incredible slowness. If there is some way to do that I will be absolutely happy. Thanks.


strtok() c++ How do I split a string with strtok() and put each part in a vector?

I'm trying to implement a basic terminal (like bash), and I'm currently trying to take in user input (as if they were entering commands in bash) and split up each by spaces and put it in a vector so I can read from the vector and attend to each command one by one. I can't seem to get my code to compile, what am I doing wrong? (here's what I have so far):  #include <iostream> #include <cstring> #include <vector> #include <string> using namespace std;  int main(){     vector<string> cmdline;     string command = "";     cout << '$';     getline(cin, command);      command.c_str();     char* tokchar;     tokchar = strtok(command, " ");       while(tokchar){         cmdline.push_back(tokchar);         tokchar = strtok(NULL, " ");     }  return 0;  }   Specifically, the compiler error is: cannot convert 'std::string' to 'char*'for argument 1 to 'char* strtok(char*, const char*)' It says the error is on the line where I set tokchar =...;  I'm not sure if this code will do what I'm hoping. How would I fix it and make it put all of the command line arguments into a vector separated by " "?


I have a problem that when I type reboot to console it works. And I don't want that, I want to be asked to run it with sudo and password. I've done a few configurations to my ubuntu, and since I'm not an expert I might messed something up.  I work with small embedded devices with Linux on them, I am root there and I reboot them from time to time, so when I type reboot as a root I don't need sudo or a password. The problem is, when I type it by mistake to my local console and my PC reboots... But I'm not root on my PC, so how can I block it?


When inspecting a PCB earlier today it occurred to me that all traces you find on modern PCB's are confined to 45 degree increments with respect to the (typically square) board edges.   What is the rationale for this?  Is this a fabrication consideration or something electrically inspired?


I have a Dell Inspiron 15 (5000 series) and am trying to dual-boot Windows 10 (already installed) and Ubuntu 16.04.3 LTS. I have a bootable USB stick, which I made using the ISO file from Ubuntu's website, and UNetBootIn (I have also tried this with a stick made from Rufus). However, when I try to boot from the USB to install Ubuntu, I am unable to do so.  I have tried booting from a USB drive on Legacy BIOS, which does start booting up Ubuntu, but it freezes a few seconds into the boot process. I have also tried booting on the standard UEFI, but adding grub (specifically, EFI/grubx64.efi on my USB stick) as a boot option. Note that when I do this, I disable Secure Boot. This does bring me to the standard grub screen, and I can click "Try Ubuntu without Installing", but it freezes on the load screen.  Any advice would be greatly appreciated! :) Thanks in advance!


Synchronized method or Synchronized block : Which one is better while writing singleton class in java?

As we know for synchronous operation while creating singleton class we make whole method as synchronized or only block of statements which are responsible for creation of object as synchronized.But, among these two approaches which one is better and why?  Approach 1  public static A getA(){       if (obj == null){           synchronized(Singleton.class) {             if (obj == null) {                 obj = new Singleton();//instance will be created at request time               }           }        }       return obj;   }    Approach 2  public synchronized static A getA(){       if (obj == null){           obj = new Singleton();//instance will be created at request time       }        return obj;   }


I couldn't help but notice that my NASM Assembly questions didn't have kind of code highlighting. Like this one:   I used Assembly and NASM tags and still didn't work. Do we have Assembly syntax highlighting? Well, not that there is much to highlight in Assembly anyway (although it'd be nice to see my symbols and registers with a different color).


how to remove ACM Reference format box in sig-conf template?

I found the following part titled ACM Reference format in the body. How can I get rid of this?   ACM Reference format: Ben Trovato, G.K.M. Tobin, Lars Thørv¨ald, Lawrence P. Leipuner, Sean Fog- arty, Charles Palmer, John Smith, and Julius P. Kumquat. 1997. SIG Proceed- ings Paper in LaTeX Format. In Proceedings of ACM Woodstock conference, El Paso, Texas USA, July 1997 (WOODSTOCK’97), 4 pages. DOI: 10.475/123 4


Prove that $\varphi$ is convex if $\varphi \left[ \int_0^1 f(x) \, dx \right] \le \int_0^1 \varphi [f(x)] \, dx$ for any measurable $f$

Q: Suppose $\varphi$ is a real valued function on $\mathbb{R}$ such that:   \begin{align*}   \varphi \left[ \int_0^1 f(x) \, dx \right] &\le \int_0^1 \varphi [f(x)] \, dx \\ \end{align*}   for every real valued bounded measurable function $f$ on $[0,1]$. Prove that $\varphi$ is convex.   My attempt:  Consider for fixed $x_1, x_2 \in \mathbb{R}$:  \begin{align*}   f(\theta) &= \theta x_1 + (1 - \theta) x_2 \\   \int_0^1 f(\theta) \, d\theta &= x_1 \int_0^1 \theta \, d\theta + x^2 \int_0^1 (1 - \theta) \, d\theta = \frac{x_1 + x_2}{2} \\ \end{align*}  Plugging this into the inequality given in the problem:  \begin{align*}   \varphi \left[ \frac{x_1 + x_2}{2} \right] &\le \int_0^1 \varphi [\theta x_1 + (1 - \theta) x_2] \, d\theta \\   \end{align*}  From here, I'm stuck. If I can show the midpoint property:  \begin{align*}   \varphi \left( \frac{x_1 + x_2}{2} \right) &\le \frac{\varphi(x_1) + \varphi(x_2)}{2} \\ \end{align*}  I know proofs from there that $\varphi$ is convex. But I don't see how to get that.


I'm seeing some weird hat behavior on the iOS app.  On some answers, I'm wearing the trophy hat.        On other answers, I'm not wearing any hat at all.        And on the web, I'm wearing the taco hat.        What's going on?   App Version: 1.6.2.5 Device: iPhone 6 OS Version: Version 9.3.4 (Build 13G35)


I'm new to LaTeX. I'm trying to create a table where one of the cells contains aligned equations.  The naive approach of nesting an align environment inside the table environment does not work:  \begin{tabular}{l r} A & B\\ \begin{align} x &= y+1\\ x &= (y+1) (y-1) \end{align} \end{tabular}   This gives the error 'Argument of \align has an extra }.'  I must admit I have no idea what that error message means... Why is it not possible to nest align and table environments? How do I put aligned equations in a table?  Thanks!


Can the Euler-Lagrange equation be used to derive the stationary action formula?

From what I understand I can use the  Euler-Lagrange equation to find the function ( Let us call L. ) where L can be the function as stated in the action formula.  But how difficult is it to actually derive the stationary action formula itself or is it the case that once I have he function I can always construct the action formula from first principles ?


Difference between search_api_solr and apachesolr

I would like to know the difference between these two modules, what are the advantages and disadvantages?


Find all integer solutions to $x^2-2y^2=1$

For the Pell's equation where $d=2$: $$x^2-2y^2=1$$ What are all the integer solutions to the equation. Apparantly there are infinitely many solutions, but how would I represent them in an expression?


how to register the submit event of a modal dialog?

I need to register the submit event from my modal bootstrap window, but I don't know which parameter to pass (dialog). The contents of my modal window are being loaded via Ajax request, but I need to call the function bindFormFinanceiroParcela (dialog) and pass through parameter some type of event or object of the type dialog in which I don't know what it is or how it works. function bindFormFinanceiroParcela(dialog) {     // Inscreve o formulário na janela modal com o evento submit     $('form', dialog).submit(function (e, i) {         if ($(this).valid() || i) {             startLoadOneMoment();             // Realiza una requisição ajax             $.ajax({                 url: this.action,                 type: this.method,                 data: $(this).serialize(),                 success: function (result) {                     // Se a requisição for satisfatória, recarrega a página atual                     if (result.success) {                          window.location = window.location;                                            } else {                         $('#contentModalFinanceiroParcela').html(result);                         bindFormFinanceiroParcela();                         //reload_dtFinanceiroIndex();                     }                     stopLoadOneMoment();                 }             });             return false;         } else {             return false;         }     });  function openModalFinanceiroParcelaSemURL(data) {     startLoadPage();      //create modal html     if (!$("#modalFinanceiroParcela").data('bs.modal'))         CreateModalFinanceiroParcela();              //load the modal content via ajax request     $('#contentModalFinanceiroParcela').html(data);          //Show modal     $('#modalFinanceiroParcela').modal({         keyboard: true     }, 'show');      // Register the submit event     bindFormFinanceiroParcela(????????);      stopLoadPage(); }  If I do it according to the source below, it works, but I can't do it that way with "load", otherwise a second request will be made. //So it works, but I can't use it, because it will make another request. $('#contentModalFinanceiroParcela').load(url, function () {     $('#modalFinanceiroParcela').modal({         keyboard: true     }, 'show');      // Register the submit event     bindFormFinanceiroParcela(this);      stopLoadPage(); });  Does anyone know how to help me? Thanks :)


Unable to get clarification on Stackoverflow

I note in the "questions that may already have your answer" section that 22 others have asked similar questions i.e. why can't new members comment.  I read many of them.  I understand your justification for requiring reps.  However, you seem to be overlooking a couple of considerations in making this pronouncement.   Sometimes the reply marked as the answer is just plainly wrong.  This may be because the discussed software has changed or the OP may have implemented the answer in conjunction with other changes and thought it was the answer that fixed the issue.  I have implemented several dozen answers found here that did not fix the issue. I have also seen answers referring to the use of classes and properties that no longer exist. But I am not allowed to inform others of this, or to ask for clarification on everything that was done.  This just happened today and there is nothing I can do about it. Sometime the answers are not clear.  Perhaps it was clear to to people with extensive experience in the tools causing the problem but to a newby you might as well be speaking gibberish.  It would help to be able to ask for some clarification on just what was meant.   Perhaps if you want to prevent extraneous comments you could provide a means just to request clarification.  Maybe a checkbox or something?    One of the explanations you provided is that it is not hard for a user to gain 50 rep points.  Actually it is very hard to do so when your job is not at the cutting edge of technology.  My customer is working with versions of software that are two or three versions out of date.  By the time I become proficient in them, no one else is using it any more.  In addition, cruising the internet to answer questions on StackOverflow, social.microsoft.com, or Experts-Exchange during working hours is a sure fire guarenteed way to get fired.


Differentiability of $f(x)$ at $0$ provided that $\lim_{x\to0} [f(2x)-f(-x)]/x$ exists?

Assume that $f:\mathbb{R}\to\mathbb{R}$ is continuous at $x=0$, and the limit \begin{equation} \lim_{x\to0}\frac{f(2x)-f(-x)}{x} \end{equation} exists. Is $f$ necessarily differentiable at 0? I was able to deduce that if $f$ is continuous in a neighbordhood of $0$ and has an isolated zero at $x=0$, it must be differentiable (unless I made an error). I believe that this result holds if there exists some $\delta>0$ such that $f(x)$ does not change sign in the neiborhoods $-\delta<x<0$ and $0<x<\delta$. But for the life of me I can't figure out a general proof (or a counterexample). Any help would be greatly appreicated!


Importing an .obj file and nothing is showing

A little bit of context, i've ripped some models from the game Yugioh duelist of the roses and was a able to open them in 3ds max to edit some of the stuff. after doing that I save the kind of deformed models as .obj and try to open them in blender but every time I try nothing shows up. its showing I have something in the outliner but no object appears! If anybody can point me in the right direction for how to fix this id greatly appreciate it!


absolutely convergent series and conditionally convergent series rearrangement

I don't understand that why the terms of an absolutely convergent series can be rearranged in any order and all such rearranged series converge to the same sum.  my textbook gives me an example that it is not so for conditionally convergent series  $1-\frac12+\frac13-\frac14+\ldots=\ln2$ $1+\frac13-\frac12+\frac15+\frac17-\frac14+\frac19+\frac1{11}-\frac16...=\frac32\ln2$   which I also don't know how to prove


Schengen Visa Valid on arrival in Schengen State and not while boarding flight

I am resident of Dubai and would be travelling to Poland on 21st May at around 22:30 ,my flight lands in Poland on 22nd at around 2:30 AM which is when my schengen visa becomes valid . I am very uncertain whether I would be allowed to board the flight?   If the answer is no then what would be your suggestion to get this sorted , contacting Embassy ?


Nautilus doesn't launch on Ubuntu 16.04 :(nautilus:3653): GLib-GIO-CRITICAL

$ nautilus   Produces the following error output.  (nautilus:3653): GLib-GIO-CRITICAL **: g_dbus_interface_skeleton_unexport: assertion 'interface_->priv->connections != NULL' failed     (nautilus:3653): GLib-GIO-CRITICAL **: g_dbus_interface_skeleton_unexport: assertion 'interface_->priv->connections != NULL' failed Could not register the application: Timeout was reached (nautilus:3653): Gtk-CRITICAL **: gtk_icon_theme_get_for_screen: assertion 'GDK_IS_SCREEN (screen)' failed (nautilus:3653): GLib-GObject-WARNING **: invalid (NULL) pointer instance (nautilus:3653): GLib-GObject-CRITICAL **: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed   Nautilus used to work before recent Ubuntu automatic software update. Any help is appreciated.  I have tried the following based on suggestion on another similar thread.  $ sudo apt-get install --reinstall nautilus-data   It didn't change anything.  $ nautilus -c   Produces the following output.  running nautilus_self_check_file_utilities running nautilus_self_check_file_operations running nautilus_self_check_directory running nautilus_self_check_file running nautilus_self_check_canvas_container running nautilus_self_check_file_utilities running nautilus_self_check_file_operations running nautilus_self_check_directory running nautilus_self_check_file running nautilus_self_check_canvas_container


Why a bullet leaves a hole on glass where stone makes scratch?

When we throw a stone it breaks the glass with scratches. But when a bullet hits the glass it leaves a small hole(not always) . I want to know the specific reason behind making hole and scratch.


Like this, only it doesn't work:  \documentclass{standalone}  \usepackage{tikz}  \begin{document}  \begin{tikzpicture}   \draw [->] (0, 0) ellipse [x radius = 2, y radius = 3];  \draw [->] (0, 0) -- (1, 0) -- (0, 1) -- cycle;  \end{tikzpicture}  \end{document}   (Edited, twice, to include an MWE that actually compiles, as requested).


If lead's electron configuration ends with 6p$^2$, shouldn't it be paramagnetic?

Doesn't lead, according to its electron configuration, have unpaired electrons? Yet why isn't it paramagnetic?


Show all post types in the same table of posts

I wonder if there is any way to show all post types in the same table of posts.  Let's say I've got 3 different post types: Movies, Books and Videogames.  Is there any way to show them all in a single table of posts?


I was reading an example, where it is calculating the square roots of $\sqrt 3 +3i$.  $w=\sqrt 3 +3i=2\sqrt 3\left(\frac{1}{2}+\frac{1}{2}\sqrt3i\right)\\=2\sqrt 3(\cos\frac{\pi}{3}+i\sin\frac{\pi}{3})$  Let $z^2=w \Rightarrow r^2(\cos(2\theta)+i\sin(2\theta))=2\sqrt 3(\cos\frac{\pi}{3}+i\sin\frac{\pi}{3})$.  But how did they get from $\sqrt 3 +3i=2\sqrt 3\left(\frac{1}{2}+\frac{1}{2}\sqrt3i\right)=2\sqrt 3(\cos\frac{\pi}{3}+i\sin\frac{\pi}{3})$?  And can one just 'let $z^2=w$' as above?  Edit: $w=2\sqrt 3(\cos\frac{\pi}{3}+i\sin\frac{\pi}{3})=z^2\\ \Rightarrow z=\sqrt{2\sqrt 3}(\cos\frac{\pi}{6}+i\sin\frac{\pi}{6})\\ \Rightarrow \sqrt{2\sqrt 3}\frac{\sqrt 3}{2} +i \sqrt{2\sqrt 3} \frac{1}{2}$


The difference between a sentence starting with 'to' + verb and starting with a gerund

What is the difference between the following two sentences?  To study English is hard.  Studying English is hard.


How do you set and reset a bit in an unsigned long long integer?

I've been working on this for hours but I still can't get my methods to work no matter how many times I look over bitwise functions. (Switching it to just pos throws an error). Bits() = default;  Bits(IType n) {      bits = n;  }  void set(int pos) {      (bits |= 1ULL << (pos-1)); }  void reset(int pos) {      // Resets (makes zero) the bit at position pos     bits  &= ~(1ULL << (pos-1)); }   For some reason it seems to be filling out the bit with the entire long.


I want to install Ubuntu on my Lenovo z51 Laptop. It has a Broadcomm bcm43162 Wifi Card.  When I boot into the Live CD, it doesnt have WiFi. When I go into the terminal and try:  sudo apt install firmware-b43-installer   It installs succesfully, but I still dont have a network connection.  A year ago I've managed to get it to work on my Ubuntu partition, but it got corrupted and I've forgotton how I did that.  I've tried Linux Mint, Manjaro & Ubuntu but they all don't seem to work.   Edit: Someone suggested:    But I've already stated that when I try  sudo apt install firmware-b43-installer   Nothing happens. And I can't reboot since I used the Live CD, because I want it to work first before I format my main partition.


ubuntu live persistense created usb not saving the data

I recently made a bootable USB of Ubuntu 18.0 LTS with unetbootin and Linux live USB creator and universal USB to save the settings and data. but every time I reboot my system my settings and data is gone. I created a new user account but this also didn't work. Where am I wrong?


Why is flux through a closed surface not infinite?

The Electric field lines coming out of a charge are infinite, So the lines passing through a closed surface should be infinite , right?


Is it safe to use a drive that previously had bad sectors (since reallocated via a Secure Erase)

My internal hard drive was playing up and diagnostics found that it had 20 bad sectors. I've since done a high security erase of the drive and all my issues seemed to go away. Disk Utility reported the drive was okay and I was able to reinstall OS X and restore from a TM backup, etc.  However, a few 3rd party apps indicate my drive now has 21 reallocated bad sectors. I imagine this is better than the previously reported 20 bad sectors (now showing as 0), but these apps are indicating my drive is still failing solely due to that.   I haven't been able to find much information on the web about lifetime of a drive after having reallocated bad sectors, so I'm unsure of what to do. Will these reallocated bad sectors become a problem, or are they indicative that the problems haven't stopped? Should I bite the bullet and just install a new SSD?


Selection of vertices surrounding a vertex (only the the ones directly touching)

I need to use this without python coding. Thanks, is there a shortcut or anything? I tried Crtl+L and just L and it just selects my whole model.


Why did Americans make up their own words for certain things?

Why did Americans come up with new words for the British English words like "sidewalk" instead of "pavement"?  I only see a reason they omitted certain letters in some words, like "colour" - "color", but I don't see any reason why they would make their own words.  Why didn't they stick with the British words?


Is there a function $f\colon\mathbb{R}\to\mathbb{R}$ such that every non-empty open interval is mapped onto $\mathbb{R}$?

I wonder  whether there is a function $f\colon\Bbb R\to\Bbb R$ with the folowing characteristic?   for every two real numbers $\alpha,\beta,\alpha\lt\beta$,  $$\{f(x):x\in(\alpha,\beta)\}=\Bbb R$$   I can't  say such a function does not exist, neither can I construct a example  Thanks a lot!


I have created a simple bash script called echo.sh. Which outputs a string. I've made sure its executable. And i then added it to the "startup applications" program through the GUI interface. However when i reboot my machine, it doesn't appear to of been executed, as there is no echo appearing in a terminal.  from my understanding shouldn't the script ,when executed, open up a terminal automatically from my understanding because of the STDOUT being the terminal file. However the script works fine if i launch it myself from the terminal.  echo.sh  #!/bin/bash  echo "hello this is a bash script talking"   Making it Executable  chmod +x echo.sh   Adding to "startup applications with correct directory to file"   Outcome  However when i reboot the system, the script doesn't run as expected, and no terminal appears with the echo message. I'm unsure as to why, and i may be completely missing the point, if so please let me know.  just to note, all my other bash scripts work , such as my "cleanup.sh" script which is also in the "startup applications" program.  Attempted fixes  I've tried redirecting the STDOUT to the terminal file /dev/tty. However this doesn't seem to work.  #!/bin/bash  echo "hello this is a bash script talking" >/dev/tty   I've also tested a bash script with just a simple rm command, just to check if it was just the echo command that was having a problem. However when added to start up applications or .bashrc file, it doesn't delete the test.txt in the same directory as the script. However works when i execute manually from the terminal.  #!/bin/bash  rm ./test.txt   I've also tested startup applications program itself with just opening Firefox, with just the command Firefox. Which works without an issue. So their doesn't seem to be an issue with the startup applications program itself?


I installed SQL Server Express on my machine and I can only connect to in in SSMS using .\SqlExpress. How do I change it so it becomes .?  I want to do this for SQLExpress which is different that the answers that are found here ""


What does this cryptic Bash command mean?

I was reading Ubuntu Forum's warning about malicious commands and found this interesting gem:  :(){ :|:& };: WARNING: The above code will crash your machine unless you have strict proc limits in place (which you probably don't) prompting a hard restart. Consider this code similar to running sudo rm -rf /.  But what does that mean? Even with my programming experience I've never seen a command that cryptic that's not assembly language.


In reviewing low quality posts, I cannot see a .  It was closed as:    The available options are as follows.


Link renders differently on client and server side when preceded by a special character

When editing a question on , I observed that a link which was not rendered in the post was hyperlinked in the edit preview (see pictures below). I tried reproducing it in the  to see if this also happens when the post is posted for the first time and observed the same. It seems to be a bug after the shift to CommonMark, leading to the different rendering of links on client and server-side. A link following a special character (without any space) is not hyperlinked in the post but is hyperlinked in the preview. A link separated from the special character with a white space appears to have no such problem. (see pictures below and my ). Link not hyperlinked in post  Same link hyperlinked in preview


I am setting up a function that will close a dropdown menu when clicked outside. The function works as intended, however it throws a error.  I am not sure what is causing the error, considering that the function works as intended.  const userBtn = document.querySelector(".header-userbtn"); const userMenu = document.querySelector(".header-usermenu");  function hideOnClickOutside(element, button) {   if (!element.classList.contains("active")) {     return false;   }   const outsideClickListener = event => {     if (!element.contains(event.target)) {       button.click();       removeClickListener();     }   };    const removeClickListener = () => {     document.removeEventListener("click", outsideClickListener);   };    document.addEventListener("click", outsideClickListener); }  userBtn.addEventListener("click", function(e) {   const chevron = this.querySelector(".chevron-wht");    this.classList.toggle("active");   chevron.classList.toggle("active");   userMenu.classList.toggle("active");    e.stopPropagation();   document.addEventListener(             /*main.js:31 */     "click",     hideOnClickOutside(userMenu, userBtn)); });   Here is the Error Message. It triggers every time the menu closes, and the function is called from the click event.  main.js:31 Uncaught TypeError: Failed to execute 'addEventListener' on 'EventTarget': The callback provided as parameter 2 is not an object.     at HTMLButtonElement.<anonymous> (main.js:31)


I was wondering if there is anyway to set a variable from a function. Let me explain with the following code:  number = 0 print number  def number_parse():     number = number + 1     return number  print number number_parse() print number number = number_parse() print number   I get the following output:  0 0 0 1   So what I am really trying to ask is, is there a way to set a variable from a function without having to call it from the line:  number = number_parse()   Can I not define a variable's value just by calling the function? What if I would like to set multiple variables (e.g. number, number_2, number_3 etc)  I am new to python and can't seem to figure this one out


Windows 10 hibernates instead of shutting down, even though fast startup is disabled

I had recently installed a major windows update (Version 1709, build 16299.125), and since then I have noticed a strange problem: whenever I shutdown the computer having open programs, I still see them at the same state when I power it back on. It seems like my computer actually hibernates instead of fully shutting down.  After searching and reading many articles, I realized there's a built-in function called "Fast Startup", which is supposed to exit all programs and hibernate instead of shutting the computer down.  Thinking the "Fast Startup" function might didn't work well (by skipping the stage of exiting all programs), I tried to totally disable the function using the following method:    1. Right click the Windows start menu button and choose Power Options.     Click on Choose What the Power Button Does.  2. If there is a Windows     UAC shield at the top with Change Settings That Are Currently     Unavailable, click it and choose Yes or enter your password to     reopen the dialog with administrative privileges.  3. At the bottom     below Shutdown Settings, it will say Turn on Fast Startup     (recommended). Deselect the option and press Save Changes.   Yet, my computer still remembers its previous state after I power it on from a (so-called) complete shutdown. Has anyone encountered a similar bug? Do you know how can I fix it?


do-release-upgrade failing on Ubuntu 16.04 LTS - says: No new release found

-- Our Situation --  We haven't been able to get do-release-upgrade to run on our Ubuntu 16.04 LTS systems in the past few weeks.   We have 100+ machines to upgrade. Have read the other solutions and none of them work so far (eg:     ) - that is except for the "brute force" method of manually changing the distro in /etc/apt/sources.list[.d/]* .. I'm not a fan of this method as it seems overly messy and not particularly friendly.   Is do-release-upgrade broken on 16.04LTS ? do-release-upgrade worked sometime mid last year, and now it isn't..   -- Some info.. --  * Require a command line based solution as we need to automate this.   We will be updating over 100 machines * None of the existing solutions get do-release-upgrade to work.     sudo do-release-upgrade     sudo do-release-upgrade -d     sudo do-release-upgrade -c * update-manager-core package is installed * File /etc/update-manager/release-upgrades has:     [DEFAULT]     #...     Prompt=lts  * File /etc/update-manager/meta-release has:     # default location for the meta-release file     [METARELEASE]     URI = https://changelogs.ubuntu.com/meta-release     URI_LTS = https://changelogs.ubuntu.com/meta-release-lts     URI_UNSTABLE_POSTFIX = -development     URI_PROPOSED_POSTFIX = -proposed     /etc/update-manager/meta-release (END)   -- Error Messages --    do-release-upgrade :         Checking for a new Ubuntu release         No new release found.   do-release-upgrade -d :         Checking for a new Ubuntu release         Upgrades to the development release are only          available from the latest supported release.    do-release-upgrade -c :         Checking for a new Ubuntu release         No new release found.   UPDATE #1   * Machines are running : Ubuntu 16.04.6 LTS  * Machines are updated every day by cron (apt update+upgrade)  * /etc/apt/sources.list.d/ubuntu.list has :     deb archive.canonical.com/ubuntu xenial partner


Hello guys I started a personal project to where I would basically make a meal planner based of how many calories a person wants to consume per day for myself. I know it maybe a tough challenge for me since I'm a beginner, but I can do it! I will leave the backend later, but for now I wanted to work on the UI and I'm having trouble with this piece of code. I want to make a list of panels to be held in a panel, based on how many number of meals they want is how many panels will appear. any insight on this will be much appreciated.   package mealplanner;  import javax.swing.*;  /**  * Created by Usman on 6/8/2017.  */ public class MealPlannerPanel extends JPanel {      JPanel[] panel;     int mealsPerDay, caloriesPerDay;     public MealPlannerPanel(){         mealsPerDay = Integer.parseInt(JOptionPane.showInputDialog("How many meals would you like per day?",null));         caloriesPerDay = Integer.parseInt(JOptionPane.showInputDialog("What is your daily calorie aim?",null));         panel = new JPanel[mealsPerDay];         for(int i = 0; i < panel.length; i++){             add(panel[i]);         }     }     public static void main(String[] args){         MealPlannerPanel planner = new MealPlannerPanel();         JFrame frame = new JFrame("Meal Planner");         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);         frame.getContentPane().add(planner);         frame.pack();         frame.setVisible(true);     } }


ArcGIS 10.1 Python Script tool wont read string variable in SQL statement

I am working on a simple script tool that selects features from a .shp and creates a new output with only those features. Basically the user specifies(from a drop down list) the county and the preserve and the tool just does a select from a .shp with all the counties and the same for the preserves. I think the problem lies in my syntax, The tool runs without errors but gives me empty outputs. However if I test it without the user input and just put a county name and preserve name in the SQL statement it works which leads me to believe Im not telling the script to use the user input properly.  Here is the select part of my script:  #Variables/Arguments CNTY = "C:\\CRTOOL\\Data\\FL_Counties.shp" AP = "C:\\CRTOOL\\Data\\FL_AP.shp" Select_County = arcpy.GetParameterAsText(0) Select_AP = arcpy.GetParameterAsText(1)  # Select arcpy.Select_analysis(CNTY, "C:\\CRTOOL\\Data\\Your_County.shp", "\"NAME\" = '%Select_County%' ") # Select arcpy.Select_analysis(AP, "C:\\CRTOOL\\Data\\Your_AP.shp", "\"LONG_NAME\" = '%Select_AP%' ")   Here are tool parameters(I have tried them with and without the ' ' in the filter list:   UPDATE: WORKING SCRIPT  #Local Variables/Arguments CNTY = "C:\\CRTOOL\\Data\\FL_Counties.shp" AP = "C:\\CRTOOL\\Data\\FL_AP.shp" Select_County = arcpy.GetParameterAsText(0) Select_AP = arcpy.GetParameterAsText(1) where = '"NAME" = ' + "'%s'" %Select_County whereB = '"LONG_NAME" = ' + "'%s'" %Select_AP  # Process: Select arcpy.Select_analysis(CNTY, "C:\\CRTOOL\\Data\\Your_County.shp", where) # Process: Select arcpy.Select_analysis(AP, "C:\\CRTOOL\\Data\\Your_AP.shp", whereB )


Step 4 of Canonical Distribution of Ubuntu OpenStack is taking too much time

I have a total of three machines. I have installed MaaS in one of my machines and the other two machines were added to the MaaS nodes list and kept in ready state.  When I run the fourth step given in the  Ubuntu documentation, both the machines went to the deployed state.  The Ubuntu OpenStack installer screen is running for too long a time. I don't know to how to proceed. Please help me. I am looking for this to do simple job scheduling in a cloud environment using OpenStack.


In QGIS 2.8, the heatmap plugin got CRS broken. I updated to 2.10, now in the plugin the dialog is broken: it does not let you choose the format.  I render layers for atlases with heatmap style. But I need to export it to GeoTIFF, and I don't see a way to do this.  Updating the QGIS is not easy in Ubuntu, since it works normally when installed from a PPA, but installing from sources, or downloading debs is  very painful.  Is there a workaround?  A command line example will do too.  edit here's a screenshot. The format list is empty, and if I write file extension manually as I did here, it still does not allow, showing a message that format is not chosen.    Meanwhile in another dialog, format choice works correctly:    Versions:


Real matrix with the property that every nonzero vector in $\mathbb{R}^n$ is an eigenvector of $A$.

so I'm supposed to let $A$ be a square real matrix with the property that every nonzero vector in $\mathbb{R}^n$ is an eigenvector of $A$. And I'm supposed to show that $A=\lambda I$ for a constant $\lambda$ in $\mathbb{R}$.  But I am having a lot of trouble with how to start this proof... Does it have anything to do with $Av=\lambda v$? I'm really confused. Any help would be appreciated.


How do you calculate your character's proficiency bonus?

How do you calculate your character's proficiency bonus in D&D 5e?


Redirecting entire old domain to new domain

I was wondering if anyone can help with this problem. So far I've had no luck experimenting and looking on forums. I have a client that had an old website. I made a new website for him with a new domain. He asked me to redirect everything on his old site, including all the pages such as website.com/shop or website.com/about. So far I've had no luck automating this. Is there any way I can redirect every page on his old site to just the homepage of the new site?


Global Variables - VisualForce Page - BaseUrl

I have a simple Visualforce page with just an Iframe inside.  I want to send as parameter to this Iframe the Instance URL.  To do this I use Global Variables, it is working for other parameters like {!$CurrentPage.parameters.id} or {!$Api.Session_ID} .  {!$Site.BaseUrl} or any other {!$Site.xxx}  working only in Force.com site.  How can I get the instance URL from this VisualForce Page?  <apex:page standardcontroller="Case"  showHeader="false" title="PIM" > baseurl {!$Site.BaseUrl}     name{!$Site.Name}  {!$CurrentPage.parameters.id}  {!$Api.Session_ID}         <apex:iframe src="anyURL" scrolling="true" id="theIframe"/> </apex:page>


In C# why can't a conditional operator implicitly cast to a nullable type

I am curious as to why an implicit cast fails in...  int? someValue = SomeCondition ? ResultOfSomeCalc() : null;   and why I have to perform an explicit cast instead  int? someValue = SomeCondition ? ResultofSomeCalc() : (int?)null;   It seems to me that the compiler has all the information it need to make an implicit casting decision, no?


Feed or alert of a specific Twitter keyword from specific Twitter account?

How do I receive an alert or create a feed for when a specific Twitter account tweets a specific keyword(s)?  For example, the author of a software application I use apparently does not have any type of feed dedicated to the updates for that software. I'd prefer not to follow his personal feed and monitor for that 1/100+ tweet mentioning the software update. I'd prefer to be notified in some fashion when they tweet a specific keyword. RSS is fine. Other tech/feed is fine.


As the title says, does Shyvana's q proc  passive  twice? Since her q essentially counts as two auto attacks (instant kill wards for example), then would each "auto" from her q proc Hydra?


I have always been puzzled by how do you arrive at Lagrangians?  That is, how do you know that the functional you need to get Newton's equations is  $$L  =  T-V(x)~?$$ Do you derive the Lagrangian first somehow or do you just guess the one which would satisfy the action to give equation's of motion? (because then you would need to know the equations of motion first.) Also, is the Lagrangian always equivalent to something resembling $T-V$, or there are other ways to determine it? More generally, is the action known before you know the equations of motion, or vice versa?  What I really wish to know is, was the Einstein Hilbert action discovered before field equations were? If so, how? My major doubt is how do you come across the Lagrangian if you don't know the equations of motion, and you can't guess $L$ then?


What is the cylinder on this wire? Is it some kind of adapter or transformer? What purpose does it serve? Why couldn’t it be incorporated into the primary adapter that plugs into the wall at the other end?


Removing all \n\r characters from a node XSLT?

wondered if you could help me please? I have node in xml that is as followed  $LOG: 08880xbpnd $ fhdsafidsfsd df sd fsd f sd fsd  I was wondering is there anyway to make all the text go on to one line so that it then can be passsed through to a javascript function? so it would turn out like this   $LOG: 08880xbpnd $fhdsafidsfsddfsdfsdfsdfsd


Time period of simple pendulum with varying mass

How do you find time period as a function of time for a simple pendulum that is in the form of a hollow sphere that is filled with mercury and there is a hole in the bottom through which the mercury is constantly falling at a fixed rate? I tried creating a function for the time period to check how it varies with the mass of mercury, but I had too many variables.   EDIT: This question was a concept based multiple choice question in my homework book. The option were time period becomes erratic, time period increases, time period decreases, time period first increases then decreases.


I need to compute the sum of the following infinite series:  $$\frac{1}{1 \cdot 3} + \frac{1}{2\cdot 4} + \frac{1}{3\cdot 5} + \frac{1}{4\cdot 6} +\cdots $$  How would I compute this sum? My teacher didn't really go over telescopic sums, and in the book it says I need to find the closed form of this sum, which I can do and I did.  $1/(n)(n+2)$  From here on though I get really confused, the book separates the fraction somehow and then tries to list the terms in closed form and factor something out? Not sure.


Avoid arrow crossing over blocks in flow chart

I've been creating a flow chart using the template I found here:    Please see the code below:  \documentclass{article} \usepackage[latin1]{inputenc} \usepackage{tikz} \usetikzlibrary{shapes,arrows} % Define block styles \tikzstyle{decision} = [diamond, draw, fill=blue!20,      text width=4.5em, text badly centered, node distance=3cm, inner sep=0pt] \tikzstyle{block} = [rectangle, draw, fill=blue!20,      text width=5em, text centered, rounded corners, minimum height=4em] \tikzstyle{line} = [draw, -latex'] \tikzstyle{cloud} = [draw, ellipse,fill=red!20, node distance=3cm,     minimum height=2em] \begin{document} \begin{tikzpicture}[node distance = 2cm, auto]     % Place nodes          \node [cloud] (a) {a};         \node [block, right of = a, node distance =5cm] (b) {b};         \node [decision, below of = b] (c) {c};         \node [block, below of = c, node distance = 3cm] (d) {d};         \node [decision, below of = d, node distance = 3.2cm] (e) {e};         \node [block, right of = e, node distance = 3.2cm] (f) {f};         \node [decision, below of = e] (g) {g};         \node [block, left of = g, node distance = 3.2cm] (h) {h};         \node [decision, below of = g, node distance = 3.5cm] (i) {i};         \node [block, left of = i, node distance = 3.2cm] (j) {j};         \node [block, right of = i, node distance = 3.5cm] (k) {k};      % Draw edges     \path [line] (a) -- (b);     \path [line] (b) -- (b);     \path [line] (b) -- node [near start] {yes} (d);     \path [line] (d) -- (e);     \path [line] (e) -- node [near start] {no} (f);     \path [line] (f) |- (b);     \path [line] (e) -- node [near start] {yes} (g);     \path [line] (g) -- node [near start] {no} (h);     \path [line] (h) |- (e);     \path [line] (g) -- node [near start] {yes} (i);     \path [line] (i) -- node [near start] {yes} (j);     \path [line] (j) -- (h);     \path [line] (i) -- node [near start] {no} (k);     \path [line] (k) -| (h); \end{tikzpicture} \end{document}   How can I create an arrow from k to h that doesn't intersect any of the other boxes or arrows?


What would be proper grammar for this sentence?

Could you please tell me how to properly write the following sentence?  I believe I know the grammar rule but I must not be creative enough to think of an alternative sentence structure.  Here's the sentence:     I would love to see houses you've been looking at.   I've never really figured out how to change a sentence like this without sounding really pompous.  Such as, "I would love to see houses at which you've been looking". This sentence sounds weird and awkward to me.


There's a pile of socks freshly washed and dried. Call it 2n of them (all pairs).   You pull one out at random. You don't have a pair (obvs) so you lay it out in the holding area. Holding area has 1 sock.   You pull another random sock from the pile. It doesn't match any of the socks in your holding area, so you lay it down next to the first. Holding area has 2 socks.  You pull out a 3rd sock. It matches one in the holding area. So you roll them both up and put them in the drawer. Holding area now has 1 sock.  What's the expected maximum number of socks in the holding area?  Or, what's a reasonable space (measured in socks) for the holding area?


What happens when you target a "magical effect" with Dispel Magic?

In D&D 5e, the spell Dispel Magic says     Choose one creature, object, or magical effect within   range.    The rest of the spell description explains that spells "on the target" of a level lower than that at which Dispel Magic was cast automatically end, and those of a higher level require a check.  This makes perfect sense when targeting creatures or objects which may have spells on them. But what does it mean to target a magical effect?  Does it mean that you can choose to target just one specific ongoing spell effect instead of stripping the whole shebang (clearing a negative spell from an ally with positive spells also in place, or a positive spell from an enemy who is under attack from a negative spell)?  Or, is this only for the special case of certain spells (like Imprisonment) which have effects which specifically mention being targeted by Dispel Magic, and since no effect is described otherwise? (This is a literal reading: a spell is a magical effect, but does not have spells on it, so the Dispel Magic effect has nothing to act on.)  Or — and I think this is a stretch — can magical effects which are not spells be dispelled by Dispel Magic? If so, what are the mechanics?


Write ‘There is exactly 1 person…’ without the uniqueness quantifier

During a lecture today the prof. posed the question of how we could write "There is exactly one person whom everybody loves." without using the uniqueness quantifier.  The first part we wrote as a logical expression was "There is one person whom everybody loves.", ignoring the 'exactly one' part of the question initially. From this he wrote  $L(x,y): x$ loves $y$; domain for $x$ and $y$: $\{\text{people}\}$  $\exists x\forall y: L(y,x)$  Which I understand to mean 'There is a person $x$ such that for all $y$, $x$ is loved by $y$' AKA 'There is a person who is loved by everyone'. I get that part.  The part I don't get is how the expression of 'exactly one'.  $\forall z(\forall y(L(y,z))\to x =z)$  which then creates the joint expression  $\exists x\forall y(L(y,x))\land \forall z(\forall y(L(y,z))\to x=z)$  I just can't seem to understand how $\forall z(\forall y(L(y,z))\to x =z)$ means exactly one here.  I suppose you can take $\forall z$ here to mean 'for any given person', which means the $\forall z$ is considering every person in the world.  This would translate the second expression block to something like, "For any given person $z$, if everybody loves $z$ then $z$ is the same person as $x$".  To me though $\forall z$ generally means for every element in the domain which I see as meaning every person in the world simultaneously, as it seems to for $y$.  Is that just plain wrong?  How can I tell when $\forall$ means 'all' and when it means 'for any (one)'?  In the previous English translation the only reason I was able to translate it (if it's even right) is because I already knew what the statement was suppose to mean.  Is it just that $\forall z$ means that this statement could be true for any element, and if so what's the difference between $\forall z$ and $\exists z$?  Someone told me that $\exists z$ would be redundant because the expression says $x=z$ but how do I know that $x$ and $z$ are automatically the same person if $\exists$ is used for both?  Sorry if this is a bit long with too many questions.  I just wanted to try to make the cause of my confusion as clear as possible so you can help me figure this out.


Python Recursion Alternatives for Training a Robot

Actually, I am writing a code to train a robot in an unspecified grid. The Robot can move only UP/DOWN/LEFT/RIGHT. I start from point [0,0]. initially, my plan was to recursively figure out the coordinates but are there any other alternatives? I get recursion limit violation error as well. How to write the non-recursive code of the following approach: def play_episodes(current_point):     global safe_block     if(mine_safe_space(current_point) and visited_before(current_point)):         check_state.add(conversion(current_point))         safe_block += 1         play_episodes([current_point[0] + 1, current_point[1]])         play_episodes([current_point[0] - 1, current_point[1]])         play_episodes([current_point[0], current_point[1] + 1])         play_episodes([current_point[0], current_point[1] - 1])


I do some minor programming and web work for a local community college. Work that includes maintaining a very large and soul destroying website that consists of a hodge podge of VBScript, javascript, Dreamweaver generated cruft and a collection of add-ons that various conmen have convinced them to buy over the years.   A few days ago I got a call "The website is locking up for people using Safari!" Okay, step one download Safari(v3.1.2), step two surf to the site. Everything appears to work fine.  Long story short I finally isolated the problem and it relates to Safari's back button. The website uses a fancy-pants javascript menu that works in every browser I've tried including Safari, the first time around. But in Safari if you follow a link off the page and then hit the back button the menu no longer works.  I made a pared down webpage to illustrate the principle.  <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">  <title>Safari Back Button Test</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">   Coding Horror     Load the page and you see the alert box. Then follow the link off the page and hit the back button. In IE and Firefox you see the alert box again, in Safari you do not.  After a vigorous googling I've discovered others with similar problems but no really satisfactory answers. So my question is how can I make my pages work the same way in Safari after the user hits the back button as they do in other browsers?  If this is a stupid question please be gentle, javascript is somewhat new to me.


Let $f:\mathbb{R}\setminus \left \{ 0 \right \}\to\mathbb{R}, f(x)=\frac{1}{x^2}\cdot e^{\frac{1}{x}}$ $x_{0}\in \left ( 0,\frac{1}{2} \right )$, $x_{n+1}=f\left ( \frac{1}{x_{n}} \right ) \forall n\in \mathbb{N}$  Show that: 1) $(x_{n})_{n\in \mathbb{N}}$ is convergent 2) $\lim_{n\to\ \infty }x_{n} = 0$  EDIT: Well, going to that link, someone says that $x_{0}$ is important when talking about the convergente of the sequence, and that's what that specific person forgot to mention.


How to calculate the integral $\int \frac{a\tan^2{x}+b}{a^2\tan^2{x}+b^2} dx$?

How to calculate the integral $\displaystyle\int \dfrac{a\tan^2{x}+b}{a^2\tan^2{x}+b^2} dx$?  It seems like a $\arctan$ of what else... but I can not work it out.  I have previously asked how to calculate the definite integral between $0$ and $\pi$ , but the answers there only use complex analysis, so they are of no help for the indefinite integral.


Before I start be easy on me I am not a stats person - I am  just on the quest for information :-)  I was tasked to generate many graphs for someone who wanted to see if the data presented with a bell shape curve vs a graph with > 1 peak - this was no biggie but silly me I thought maybe it would be easier to run the data thru some stats package like R that would flag the populations that need to be looked at with a graph. The quest has led me to  reading Shapiro-Wilk, Anderson–Darling test etc but various people with more knowledge than I still pointed to the graphing of data as the only way to verify Normal Distribution.  So my question is is there any Statistics method I can run the following data thru to flag the data for further investigation instead of graphs ?? Instead of Counts of Patients by days should I just look at full list of DaysInHospital  Thanks     Data is plotted with a graph per disease with the data plotted   x-axis - Days in Hosiptal   y-axis - Cnt of Patients     DiseasePopulation #1  ( DaysinHospital,Cnt of Patients) = {(1,1),(2,1),(3,3),(4,6),(5,2),(6,1),(7,1),(8,1)}   DiseasePopulation #2  ( DaysinHospital,Cnt of Patients) = {(1,1),(2,1),(3,1),(4,2),(5,6),(6,3),(7,1),(8,1)}


Black screen after installing graphic drivers

I just installed the nvidia drivers for my gpu following this . After the reboot i quickly see tty1 login but then the screen goes black with a flashing underscore (_) and I can't do anything.  Im running Ubuntu 15.10


lsusb relevant output Bus 001 Device 006: ID 0bda:8812 Realtek Semiconductor Corp. RTL8812AU 802.11a/b/g/n/ac WLAN Adapter  Upon plugging the device it is recognized by lsusb, however when I go to wireless settings no adapter is recognized. The driver is installed (by going to software and updates -> addition drivers and selecting the open source driver).


Could alias python=python3 in my bashrc cause problems?

I would like to use python3 as my default python when working with the terminal. If I added the line alias python=python3 in my ~/.bashrc, could that cause problems with other programs?


I love everybody, but it is your ignorance that which I cannot stand.   Can I say that which in the statement I made?


The rectangular can be covered by finitely many squares.

I'm thinking about a problem. It states that :  If a rectangular (with length $a$ and width $b$; $a>b>0$ ) can be covered by finitely many squares, then $\dfrac{a}{b} \in \mathbb {Q}$.   (I've thought about an idea: Choose some sequences of squares in type I and type II, an arbitrary sequence of type I has sum of the sides of all squares (in this sequence) is equal to $a$, a sequence of type II has sum of the sides of all squares (in this sequence) is equal to $b$.   If we can construct some sequences of type I and type II such that if a square belongs to exactly one sequence of type I if and only if it belongs to exactly one sequence of type II, and there's no squares that belong to at least 2 sequences of one type, then we can conclude that $\dfrac{a}{b}\in \mathbb {Q}$.)


I have an ArcGis 10.3 license for one year. When I check my authorized extensions I can see I have authorized the Data Interoperability, but when I try to install the extension is not available in the wizard installation. I could not found any executable in the Esri web.   Does anyone know where can I download the Data Interoperability setup.exe?   It's not in the directory installation; I have not a DataInterop folder in it.      the problem is that I can not install it. Once installed, checking it is for activating, but the problem is that does not appear in customize>extensions, I need first to install it.


When I leave wet clothes in the open air, they will get dry over time by themselves even at room temperature. I know that somehow the water becomes vaporized; it's not "disappearing". For that, it needs to get energy from its environment and probably it's getting this energy from heat. But since it is at the same temperature with the clothes or its environment, I don't understand how an energy transfer can occur. Doesn't this violate the definition of temperature, which is only defined to determine where heat will flow?   So the question can also be expressed as: How can water get heat (if not heat, what?) from its environment when there is no temperature difference so that it can evaporate?


Can't Access Boot Menu. Wants to Remove Ubuntu and Install Win7

I recently purchased a desktop just for office use. It did not come with an OS. I had someone install Ubuntu to prepare it for ViciDial because I work at home and some clients ask for me to provide for my own dialer. The guy said that I need Ubuntu for the ViciDial to work but he did not finish what he started and I can no longer find him.  I don't know how to use Ubuntu. I searched online on what to do. I followed instructions on what keys to press and my partner and I even went as far as pressing keys from ESC to F12, to Shift (press and hold) and Del but we were still not able to access the boot menu so we can install the Win7 from a CD. Every time we turn the PC on, it just shows a black background with a gray text field in the middle asking for a password. We don't know what the password is.  I'm sorry if I cannot provide other details. I don't have any other information on what he did with the computer. I'm lost and I just want to use my PC again.  In addition, can I still use Win7 if I setup ViciDial?


Let $a,b,c \gt 0$. Prove that (Using Cauchy-Schwarz) :   $$\sqrt{\frac{2a}{b+c}}+\sqrt{\frac{2b}{c+a}}+\sqrt{\frac{2c}{a+b}} \leq 3$$   I tried to use Cauchy-Schwarz in the following form $$\sqrt{Ax}+\sqrt{By}+\sqrt{Cz}\leq \sqrt{(A+B+C)(x+y+z)}\tag{1}.$$   I wrote $$\sqrt{\frac{2a}{b+c}}+\sqrt{\frac{2b}{c+a}}+\sqrt{\frac{2c}{a+b}}=\frac{\sqrt{2a(c+a)(a+b)}+\sqrt{2b(b+c)(a+b)}+\sqrt{2c(b+c)(c+a)}}{\sqrt{(a+b)(b+c)(c+a)}}.$$  and then I applied on $(1)$:  \begin{eqnarray} A &=& 2a(c+a)   &\mbox{and}&  x=a+b;\\  B &=& 2b(a+b)   &\mbox{and}&  y=b+c;\\ C &=& 2c(b+c)   &\mbox{and}&  z=c+a , \end{eqnarray}  but I did not obtain anything. Thanks for your help. :)


How do I correctly estimate heat output for heater wire

This is based on a problem that came up today. During the course of this problem I realized that I wasn't so sure I understood the relationship between wattage and heat produced.   In the past we did a test in the lab using .305 Ω /ft wire. The jacket is rated for 150C. We were able to get about 6.5A (at 3.66V)  out of it at 24C ambient, with out exceeding the jacket rating. I want to estimate what the ampacity of 0.027  Ω/ft wire is. So I am wondering if I did it correctly, because this amperage seems a little high for the wire to handle, then again most copper wire is only rated at 90C.  So the math I did on it was this  So you do .305 * 2 = .61 Ω /ft 6A^2 * .61 Ω = 21.62W   (I^2*r = W) 21.96W * / 2ft = 10.98 W/ ft  So would it be safe to assume that if I did the same with a 0.027w/ft wire with the same jacked I would arrive at this amperage?  If you start with 11W/ft * 2ft = 22W  0.027 Ω * 2ft = .054 Ω Sqrt(22W/(0.054 Ω)) = 20.18A  ETA: we are planning on testing this tomorrow when we get some wire in. So we shall find out.


Is it more appropriate to use WHAT or WHICH in this question?

I am wanting to know who rules Canada. Should I ask: "By WHAT monarch is Canada ruled?" or "By WHICH monarch is Canada ruled?" (The answer would be: "Canada is ruled by the British monarch Elisabeth the second.")


face is flickering in blender and invisible in unity and i cant add a texture

I have an invisible face in unity, and a black/flickering face in blender, I've looked it up,  but cant seem to find answer, so I have no idea how to fix it.    I have tried things like normalizing, it did fix parts of my problem, but this is the only one left and I can't seem to add a texture to the cube for some reason, as it just appears white.


polynomial converges uniformily to analytic function

Let $D=\{z:|z|<1\}$.   suppose $f(z)$ is analytic on $D$ and  continuous on $\{z:|z|\leqslant1\}$. prove that there exists polynomial sequence  $\{P_n(z)\}$ such that $\{P_n(z)\}$  converges uniformily to $f(z)$ on  $\{z:|z|\leqslant1\}$


Using induction to prove that $\sum_{r=1}^n r\cdot r! =(n+1)! -1$

Use induction to prove that    $\displaystyle\sum_{r=1}^n r\cdot r! =(n+1)! -1$   I first showed that the formula holds true for $n=1$.  Then I put n as $k$ and got an expression for the sum in terms of $k$.  I then found the sum till the $(k+1)$th term by adding the $(k+1)$th term to both sides of the equation and compared it to the sum expression I get by plugging $k+1$ into the sum expression given in the question - they don't match.


Why python throws away error for referencing a global variable if later we define that same as local variable?

I'm just curious how python know beforehand that a variable is local and not reference the global variable instead. Please have a look on two versions of the code.  eggs = 'global' def spam():     print(eggs)     eggs = 'local' spam()   While, if i comment eggs = 'local', python refer to global variable.   eggs = 'global' def spam():     print(eggs)     # eggs = 'local' spam()   Please help me with understanding as to what i'm missing.  Edit: Found the answer here:


If $\|u\| \leq \|u+av\|$ for all $a \in F$,   How can I show that $\langle u,v\rangle=0$?  I know a standard solution uses $\operatorname{Re}$ and $t =$ something but was wondering if there was perhaps an easier solution? Thanks!