I am upgrading a vintage 10speed, new chain was purchased. The new chain was a couple of links shorter than the original that I removed. I currently have the new chain connected with a piece of wire. See picture below:    It seems that it fits, I had the chain on both lower sprockets, front and rear and it seems to function fine when I move the chain on different gear combinations. Once I remove the piece of wire it will be a little tighter but it seems there is some play in the length. The rear derailleur just moves if I increase or decrease the chain length slightly. Just wondering if this is correct, is there some degree of flexibility in terms of how long the chain can be ? Does the new chain have to be the exact same number of chain links as the old one ?

My chain broke and in a moment of silliness (I was cold wet and slightly annoyed)  I threw the broken one away before thinking about measuring the new one.  Is there a guide to getting the chain length/tension correct ?  It's an 8 speed road bike (Shimano Sora back, double ring front)


I have created two sites. They have the same modules and themes available, however I want them to be complete clones of each other without doing a manual database export and import.   I attempted using Drupal 8's configuration synchronization but I receive the following message  The staged configuration cannot be imported,  because it originates from a different site than this site.  You can only synchronize configuration  between cloned instances of this site.   I've attempted using the  module. But I don't see an option for exporting and importing to separate sites.  I've also looked at a similar question here  However that applies to Drupal 7.  Is there a way to import and export nodes, site settings, and configurations such as menu items and what modules are turned on or off from one site to another?  UPDATE: I've discovered that I might be able to use configuration synchronization if I get the UUIDs to match, but I'm having trouble running drush on my multisite. Is there a way to manually change the UUID in the database?

This is what I'm trying to do:  I have a website A where I make configuration changes and add other stuff. Now I create a website B. I would like to add the configuration changes from website A to this website.   I know the UUID of both websites have to be the same (like staging & production environment). In "" they explain how to do this with drush cget system.site.   The problem is when I run drush cget system.site in my website A I get the following drush error:     Command config-get needs a higher bootstrap level to run - you will need to invoke drush from a more functional Drupal environment to run this command.                                                               [error]   The drush command 'cget system.site' could not be executed.                                                                                [error]   Drush was not able to start (bootstrap) the Drupal database.                                                                                [error]   Hint: This may occur when Drush is trying to:    * bootstrap a site that has not been installed or does not have a configured database. In this case you can select another site with a working database setup by specifying the URI to use with the --uri parameter   on the command line. See drush topic docs-aliases for details.    * connect the database through a socket. The socket file may be wrong or the php-cli may have no access to it in a jailed shell. See  for details.   Drush was attempting to connect to:  Drupal version         :  8.0.0-rc1  Site URI               :  http://default  Database driver        :  mysql  Database hostname      :  localhost  Database port          :  3306  Database username      :  root  Database name          :  s_1  PHP executable         :  /Applications/MAMP/bin/php/php5.5.10/bin//php  PHP configuration      :  /Applications/MAMP/bin/php/php5.5.10/conf/php.ini  PHP OS                 :  Darwin  Drush script           :  /Users/myname/.composer/vendor/drush/drush/drush.php  Drush version          :  8.0-dev  Drush temp directory   :  /tmp  Drush configuration    :  Drush alias files      :  Drupal root            :  /Applications/MAMP/htdocs/s1  Site path              :  sites/default  Sync config path       :  sites/default/files/config_bZM1aJhLcWGpFZJEzfEw_pKF4g71jOdkSRti30k540BAwE9GQ4U6p469a9VxyJS4j4JVfC58qg/sync   I've installed the latest version of drush .. . I'm working with the release candidate of Drupal 8. Is there another way to get my UUID? Or do you have a tutorial or a video/blogpost of somebody who already did this?  UPDATE:  Ok, I was able to retrieve the UUID from website A and changed the UUID in website B so they have the equal UUID.  After that I changed the system site slogan of website A.  Then I did an export of the configuration in website A. But when I tried to import it in website B I got 137 new files to sync .. . The UUID is different in all files like this:    When I tried to synchronize I got the following error:


I've been asked to give a speech tomorrow. Since I'm not prepared I said:  "Had you told me earlier I could've prepared for it."  Q 1) Was the response correct?  Q 2) Is it the third conditional since there a two hypothetical past events? (One is the he didn't tell me earlier and the other one is that I couldn't take preparation.)  Q 3) What's the difference between my original sentence and the following sentence:  "If you had told me earlier I could've prepared for it."

Can this:     These same officials, however, would have been appalled had they known what was going on behind this façade of self-help.   be rephrased as     These same officials, however, would have been appalled if they had known what was going on behind this façade of self-help.   ?


I know how to split strings in Python using square brackets ( [3:] ) / whatever number you want, but I cannot find how to do that in JS. Nothing seems to match what I am looking for. I am not very experienced in JS so I apologise if this has a very obvious answer.

I have this string  'john smith~123 Street~Apt 4~New York~NY~12345'   Using JavaScript, what is the fastest way to parse this into  var name = "john smith"; var street= "123 Street"; //etc...


I have a div that is width 100% and height 100%. Inside I have a 200px x 200px div. I'd like the 200px x 200px to align to the vertical and horizontal center of the outer div. Like in Photoshop when you align to the vertical or horizontal center. I've only been able to align from the edges so far. Is this possible?   Thanks

How can I horizontally center a
 within another
 using CSS?

Foo foo


When a > is encountered in a HTML comment the comment breaks. Take the following markdown source: <!-- Here is an example of this working fine.  And a second line to show that's not the problem. -->  <!-- This isn't visible like you would expect.  > Everything from here is visible. -->  Which renders as:    Everything from here is visible. -->   Here is an example of the above part of the question in the preview screen.    There are two comments, one completely hidden the other partially visible. This means I can't hide some HTML used to get a render. This means if I, or others, need to update the render we either don't have the HTML available or I have to clutter the post.

If I try to put something like this into a question or answer  <!-- <br>s are important here -->   the first > after the "br" is matched to the first < before the "!--", resulting in this being displayed:     s are important here -->   This happens in both previews and actual posts. I'd say it's a bug.  HTML comments shouldn't be treated as regular HTML tags; <!-- should only be matched to -->.


So imagine we have a mass attached to a string and spin it. If angular momentum is conserved then why does the object not have a tendency to move in a curved path if the mass is suddenly let go off. Linear momentum appears to be conserved in this case at an instantaneous point where the mass $M$ would have velocity $v$ at any given point and hence a linear momentum of $Mv$ which presumably dies out due to gravity and drag. Where is the angular momentum gone?

Since the tension force is a central acting force, the torque on an orbiting ball about that center is zero. But if the rope is cut down during motion the torque would still remain zero. This would mean that angular momentum of the orbiting ball should be conserved, but I find everywhere that ball will move in a straight line tangentially. What is wrong in my reasoning?


I wrote a Java program, in which, I need to append a string   " u13a2" to an existing one "u1234 u12de u1386 ... u15a3".  So gradually the string becomes longer and longer. I found the time spent on each appending also becomes longer and longer. Is there any way that we can improve this to some extend ?  The implementation came to my mind includes:  unicodeArray += " "+unicode;   or  unicodeArray = unicodeArray.concat(" "+unicode);   They gave similar performance. I think the main reason that causes these bad performance is the special type String. It creates a new object for every assignment. If you also think so, does this mean I'd better use another type, like byte array?

What is the main difference between StringBuffer and StringBuilder? Is there any performance issues when deciding on any one of these?


Can we add characters like α π Σ µ σ ♂   ╩ Φ ¥ ∩ ∞ ε in the AES 256bit CBC Encryption Key? Does it make the key more unique? In my VB.NET application I am using a key like this: "∩TY&Hjubf78▐Φ4≥╬V% ÷⌡Uαπ^f7cHJßF" Does it make any difference in Encrypting the data?

We all know that AES uses Key, IV and salt. But what if we add special ASCII characters like Alternate 255 (" ") or Alternatively 163 ("£") or Alternate 224 ("α") in the Key or IV or salt. Does it add extra security?


Copy from my exercise book:     Let $R$ be a commutative ring (not necessarily with identity). For an   ideal $A \subseteq R$ we define the radical $\sqrt{A}$ of $A$ by   $$\sqrt{A}:=\{x \in R : x^n \in A \text{ for some } n \in  \mathbb{N}\}$$   Now I should show that $\sqrt{A}$ is an ideal in $R$. Everything is easy except the part where I should show that if $x \in \sqrt{A}$, then also $-x \in \sqrt{A}$. My idea was to show, that $x^n \in A$ for some $n \in \mathbb{N}$, then also $(-x)^n \in A$. Intuitively we should end up with something like $(-x)^n = \pm$ but I am not sure how to prove it. The solutions in the book are rather confusing, since they say something like since $R$ has identity...what was not assumed in the exercise.

I am given that $R$ is a commutative ring, $A$ is an ideal of $R$, and $N(A)=\{x\in R\,|\,x^n\in A$ for some $n\}$.  I am studying with a group for our comprehensive exam and this problem has us stuck for two reasons.  FIRST - We decided to assume $n\in\mathbb{Z}^+$ even though this restriction was not given. We decided $n\ne 0$ because then $x^0=1$ and we are not guaranteed unity. We also decided $n\notin\mathbb{Z}^-$ because $x^{-1}$ has no meaning if there are no multiplicative inverses. Is this a valid argument?  SECOND - We want to assume $x,\,y\in N(A)$ which means $x^m,\,y^n\in A$ and use the binomial theorem to expand $(x-y)^n$ which we have already proved is valid in a commutative ring and show that each term is in A so $x-y$ is in $N(A)$. The biggest problem is how to approach the $-y$ if we are not guaranteed unity. Does anyone have any suggestions?  Thank you in advance for any insight.


Given recursively defined sequence $(a_n)$: $$a_1=1$$ $$a_2=2$$ $$a_{n+1}=n(a_n+a_{n-1}), n\geq 2$$  Find the formula for the general term $a_n$.   This is what I did:  So the first few terms are: $a_1=1, a_2=2,a_3=6,a_4=24,a_5=120,...$  I guess the general term can be written as $n!$. Let's prove it by mathematical induction:   Base case: $a_1=1!=1$ so it's true for $n=1$. Let's assume it's true for some $n$,i.e. $a_n=n!$. Then $$a_{n+1}=n(a_n+a_{n-1})=n(n!+(n-1)!)=n(n(n-1)!+(n-1)!)=n(n-1)!(n+1)=(n+1)n(n-1)!=(n+1)!$$  Using the principle of mathematical induction we've proved that the general term of this sequence is $n!$.  Is this proof valid? I'm not sure whether it's allowed to put $a_{n-1}=(n-1)!$ here.

The problem states:  Suppose $a_0,a_1,a_2,...$ is a sequence such that $$a_0=a_1=1,\ \ \ a_{n+1}=n(a_n+a_{n-1})\ \ \ (n\ge 1).$$  Guess a formula for $a_n$, valid for $n\ge 1$, and use mathematical induction to prove that your guess is correct.  I used this equation (and check with WolframAlpha) to find the results of a few different cases.  $$a_2=2,\ a_3=6,\ a_4=24,\ a_5=120.$$  Unfortunately, I'm not really sure how I can prove this. I would appreciate any help in solving this!


I'm sorting an array following . When I use a compareFunction parameter, Internet Explorer 11 is not sorting properly.  I have a team array with players. These players have names:  var team = [   {name:"Waldo"},    {name:"Sarah"}   ];   But I want to display them at the stadium video board sort by alphabetical order. So I have a list to append them when the DOM is ready:  MyHtml
My Team after sorting
       <button onclick='sortAndDisplay()'>Click here to sort by Name</button>

   My Javascript code  function sortAndDisplay(){   $("#myTeamAfter").empty();   team.sort(function(a, b){return a.name > b.name;});   for(var i=0; i < team.length; i++){     $("#myTeamAfter").append( "
" + team[i].name + "
" );   } }   Problem is that some Clubs use Internet Explorer 11 at their stadiums, and sort() function when I use my own compareFunction is not working properly on IE11, so Waldo is displayed first than Sarah and the fans are confused.  I've created a  where you can reproduce it:   Firefox 33.1                - Working!! :) Chrome 39.0.2171.65         - Working!! :) Internet Explorer 11.0.9600 - Not Working :(   Any idea to resolve the sort() for every browser?  Thanks!

I have a list of objects I wish to sort based on a field attr of type string. I tried using -  list.sort(function (a, b) {     return a.attr - b.attr })   but found that - doesn't appear to work with strings in JavaScript. How can I sort a list of objects based on an attribute with type string?


I took the GRE in August and scored a 301 and took it recently again and scored a 308. My field of work is primarily in Behavioural Economics so I plan on applying to specialized and general Economics grad school programs. I have a strong profile with internships in various organizations within my field and outside it as well as several publications and a good CGPA.   My questions are:    What are my chances of getting into good/top grad school programs in the U.S/UK?  Should I consider applying to places outside of the US that don't require the score at all?    Thanks in advance!

When applying to a PhD program in the US, how does the admissions process work? If an applicant is weak in a particular area, is it possible to offset that by being strong in a different area?  Note that this question originated from this . Please feel free to edit the question to improve it.


I am using grep to see a log of one of our systems.   When I type "cat server.log | grep PPHI245" it shows the output below:    But, when I type just "cat server.log" it shows the output below:    Look the red underlined text that I marked on the screenshot. It is the continuation of the error message.   Please, I would like to use grep to display the full error message, not just the first line of the error.  How can I do this?

I am trying to search a file for a pattern and if the it is found I want to see the line and 10 more lines of the result.  so far I have  grep -n pattern file | cut -d: f1    now not sure how to use this out put to do the print with the logic like   sed -n result,(result+10)p file   probably  going to have a few issued if it pattern is in multiple lines.  Any help is appreciated


Which of the following sentences is grammatical:   The boss could not believe what he saw yesterday morning when he entered the office. The boss could not believe what he was seeing yesterday morning when he entered the office.   I know that see is a stative verb, but can’t believe what I’m seeing or something like that is used fairly often too. I hope someone can help me out.

In which cases would you say, "I am seeing" instead of "I see"?


The question  was recently bumped to the top of the homepage. Glancing idly at the , I noticed the following peculiarity:    Wait what? The question had already been deleted, but the Community bot somehow felt the need to delete it again? How can that happen?  What's going on there?

I noticed  (10k-only) that was apparently deleted by Community more than five years after it was originally deleted, but no events (neither undeletion nor anything else) have occurred since the post was first deleted.  The revision history shows two consecutive "post deleted" events: one in July 2009, and the other in December 2014:    Interestingly, the deletion banner on the question itself only later shows the Community user's later deletion:    I checked the post's , where the reason for the Community user deleting a post is usually listed if it wasn't as a result of the Roomba (e.g. was a negatively-scored post when the user's account was deleted, the user was destroyed, etc.). However, the relevant timeline entry lists some cryptic text, which I searched for and couldn't find the meaning of:    What does "help post localization backfill" mean, and why is there this extra "post deleted" event?


Suppose that $f$ is a function such that $f'(x) = \frac{1}{x}$ for all    $x > 0$. Prove that if $f(1) = 0$, then $f(xy) = f(x) + f(y)$ for all    $x, y > 0$   I've tried applying the Mean Value Theorem, such that $f'(x) = \frac {f(b) - f(a)}{b - a} = \frac {1}{x}$, where $y = f(x)$ if continuous on $[a,b]$ and differentiable on $(a,b)$ such that there exists at least one point $c ∈ (a,b)$.   I'm probably wrong, but i don't know how do i really approach this question and what they are really asking for (e.g. $f(xy) = f(x) + f(y)$)

Suppose f is a function such that $f'(x) = \frac{1}{x}$ for all $x > 0$. Prove that if $f(1) = 0, then f(xy) = f(x) + f(y)$ for all $x,y > 0$  As stated above, how do i go about doing this question?   Hi all, i would like to apologize if the question is missing context or other details.   This question was part of my calculus tutorial. I was on the topic of application of differentiation when this question was given to me.  Thus far i have learnt about intermediate value theorem, mean value theorem, rolle's theroem, Fermat's thereom.  As of this point in my learning, i have not touched upon integration. The only reason why i accepted the answer with integration in it was because i understood it.  Thus i believe i am suppose to use one the few theorems that i've stated to solve this question. But i have no idea where to start.  At first i differentiated the equation $f(xy)=f(x)+f(y)$ with respect to x  i believed the answer to be $f'(xy)\frac{dy}{dx}=f'(x)+f'(y)\frac{dy}{dx}$  which would be $\frac{1}{xy}\frac{1}{x}=\frac{1}{x}+\frac{1}{y}\frac{1}{x}$  At this point a few questions came to my mind  1) am i suppose to differentiate the eqn in the first place 2) what has $f(1)=0$ got to do with anything 3) what theorem am i suppose to use to solve this question  This was my thought process throughout the question and i hope someone would point out my mistakes. Thank you


I have a function that return or should return all the rows selected from a database table. However, it returns only the first rows. I don't quite understand why the rest rows are not returned when i use the 'return' keyword. The code is a bit long, so i'm including a sample code which is a bit similar terms of functionality. I believe if i can get a fix for this, i should be able to fix the one in the main code. My sample code is below. In this code, only the color yellow is printed. Please anybody know why?   def color_choser():     colors = 'yellow', 'green', 'orange', 'blue', 'white', 'pupple', 'red', 'mangenta'     for color in colors:         return color print(color_choser())

The canonical way to return multiple values in languages that support it is often . Option: Using a tuple Consider this trivial example: def f(x):   y0 = x + 1   y1 = x * 3   y2 = y0 ** y3   return (y0, y1, y2)  However, this quickly gets problematic as the number of values returned increases. What if you want to return four or five values? Sure, you could keep tupling them, but it gets easy to forget which value is where. It's also rather ugly to unpack them wherever you want to receive them. Option: Using a dictionary The next logical step seems to be to introduce some sort of 'record notation'. In Python, the obvious way to do this is by means of a dict. Consider the following: def g(x):   y0 = x + 1   y1 = x * 3   y2 = y0 ** y3   return {'y0': y0, 'y1': y1 ,'y2': y2}  (Just to be clear, y0, y1, and y2 are just meant as abstract identifiers. As pointed out, in practice you'd use meaningful identifiers.) Now, we have a mechanism whereby we can project out a particular member of the returned object. For example, result['y0']  Option: Using a class However, there is another option. We could instead return a specialized structure. I've framed this in the context of Python, but I'm sure it applies to other languages as well. Indeed, if you were working in C this might very well be your only option. Here goes: class ReturnValue:   def __init__(self, y0, y1, y2):      self.y0 = y0      self.y1 = y1      self.y2 = y2  def g(x):   y0 = x + 1   y1 = x * 3   y2 = y0 ** y3   return ReturnValue(y0, y1, y2)  In Python the previous two are perhaps very similar in terms of plumbing - after all { y0, y1, y2 } just end up being entries in the internal __dict__ of the ReturnValue. There is one additional feature provided by Python though for tiny objects, the __slots__ attribute. The class could be expressed as: class ReturnValue(object):   __slots__ = ["y0", "y1", "y2"]   def __init__(self, y0, y1, y2):      self.y0 = y0      self.y1 = y1      self.y2 = y2  From the :  The __slots__ declaration takes a sequence of instance variables and reserves just enough space in each instance to hold a value for each variable. Space is saved because __dict__ is not created for each instance.  Option: Using a  (Python 3.7+) Using Python 3.7's new dataclasses, return a class with automatically added special methods, typing and other useful tools: @dataclass class Returnvalue:     y0: int     y1: float     y3: int  def total_cost(x):     y0 = x + 1     y1 = x * 3     y2 = y0 ** y3     return ReturnValue(y0, y1, y2)  Option: Using a list Another suggestion which I'd overlooked comes from Bill the Lizard: def h(x):   result = [x + 1]   result.append(x * 3)   result.append(y0 ** y3)   return result  This is my least favorite method though. I suppose I'm tainted by exposure to Haskell, but the idea of mixed-type lists has always felt uncomfortable to me. In this particular example the list is -not- mixed type, but it conceivably could be. A list used in this way really doesn't gain anything with respect to the tuple as far as I can tell. The only real difference between lists and tuples in Python is that lists are , whereas tuples are not. I personally tend to carry over the conventions from functional programming: use lists for any number of elements of the same type, and tuples for a fixed number of elements of predetermined types. Question After the lengthy preamble, comes the inevitable question. Which method (do you think) is best?


After installing Ubuntu in dual boot mode, I'm trying to switch back into Windows but when I boot up my computer and I'm in GRUB the only OS listed as an option to boot to is Ubuntu.   The SSD where Windows 10 was installed now seems to be completely empty when viewed in Ubuntu. I never formatted the drive so I have no idea why this is happening.

I installed Windows on my computer, followed by an installation of Ubuntu. However, now I'm unable to boot into my Windows install.  What can I do to fix this?


I have to connect Local LAN in wired network and Internet in WiFi is it possible

I am on an intranet that is not connected to the Internet and a Wi-Fi router with connection to the Internet. When I am connected to the wireless network, I can browse the Internet, but I cannot browse my LAN with my Ethernet cable connected.  How can I browse the Internet via my Wi-Fi router and at the same time browse my local LAN web application via my connected Ethernet cable?


I have a field in JSF2, I tried execute a validation in this way:  <h:inputText value="#{manutencaoContratoBean.contrato.nuContrato}" style="text-align: left; width: 90%; "> <f:convertNumber pattern="#######" maxFractionDigits="0" maxIntegerDigits="16"/>     And thus:  <h:inputText value="#{manutencaoContratoBean.contrato.nuContrato}" style="text-align: left; width: 90%; ">   <f:convertNumber integerOnly="true"/     However, my field only makes a validation and show me a message, I would like just the insertion of numbers, not Strings, this is possible ?  Is possible a insertion only of numbers ? I'm using RichFaces 4, if that's relevant.  I found this, it´s work well:  onkeypress="if(event.which &lt; 48 || event.which &gt; 57) return false;"   But this not allow a click on the backspace button, in case the user make a mistake.  Thanks in advance for all !

Is there a quick way to set an HTML text input (<input type=text />) to only allow numeric keystrokes (plus '.')?


I'm an iranian citizen with having Iranian passport and USA permanent resident visa currently in Turkey for a visit and have a return flight to USA.   Below is information about my return flight to USA and according to that I have a question please:   My return flight to USA is a transit flight from Antalya AYT airport to London Gatwick airport with Thomas cook airlines and then my next flight is on the same calendar day and at the same airport  (London Gatwick) with Norwegian Airline which I have confirmed flight ticket for my onwarding flight. So my final destination is USA.  I need your assistance with my question please about whether or not I need any other travel documents like transit visa for my transit flight from Antalya AYT airport to London Gatwick airport with Thomas cook airline?

Is there a website or some other way to find out if I need a transit visa for a short stop in the UK on my way somewhere else? Ideally this should give me the answer for all nationalities, and take into account any other visas I may have.


I am a British citizen married to a Tunisian citizen. We live together in Tunisia and we are planning to go to Italy for holiday. My question is: is it free of charge or he need to pay fees? What documents does he need to show to the embassy when he applies?

I'm a British citizen and my wife is in the UK on a spouse visa. She holds a BRP card. We're planning to visit Germany and some other Schengen countries, and I've got a question around visa requirements/supporting documents.  I've read in few places (i.e ) that the visa requirements are more relaxed if the applicant is a spouse of a UK citizen, and is travelling with the UK citizen.  How relaxed are the requirements? Does my wife need to submit supporting documents for accommodation, finances, flight booking, etc.? Or is it simply submitting the application form alongside the passports and BRP? (i.e standard documentation for Schengen visa application section from )


I have tried right clicking on the file selecting properties and then the permissions tab and setting it to execute. However, when I double click the file it opens in gedit. What do I do?

How can I make a bash script executable by double clicking just like .exe files in Windows? I tried , but there are two consequences:   the terminal twinkles, disappears, and nothing is done. you must specify to run in terminal in order to work.   I have a script that installs tomcat on an offline PC, including all dependencies of tomcat in the script. I need to make the script work on double clicking like windows since most who use the script will not be familiar with Ubuntu.  Forget the above explanation. I want to make a script that can be run by double-clicking on it, without using the terminal. Anybody knows how?


Is there a command-line program similar to nano or xtree in looks (i.e., ncurses-based) that will show me all the files in a directory, that will let me work through them all making the changes needed and then applying them?

I need to rename the following:  file_001_loremipsum.png file_002_dolor.png file_003_sit.png file_004_amet.png file_105_randomness.png   into  upl_loremipsum.png upl_dolor.png upl_sit.png upl_amet.png upl_randomness.png   How do I make it happen with just one simple line of terminal command?


I disabled the lock in the "Brightness & Lock" but I still get the lock screen when is resumes/wake from suspend. Although the option "Require my password when waking from suspend" is unchecked

When I'm watching a film in Mythtv the screen turns to black every 10 - 15 mins and I have to log back into Ubuntu. Very annoying!  How do I disable the black screen / screensaver / logout in Unity?  There no longer seems to be any options to turn the screen saver off as there were in Ubuntu prior to Unity.


Its a conference paper that broadly says:  "There is X, Y, Z, Biguri et al, articles out there, but here is a table with each of the works and their limitations, and why ours is better"  And then lists a bunch of things on my published article (about a software tool) claiming it does not contain several features. The problem is, the tool has and always had most of the features they say it hasn't. They are published and clearly demoed and showcased in the webpage.   Their paper has some credit, it is still good work and its not invalid because of their mistakes. But it is seriously misrepresenting my work.  What should one do in this case?   I was thinking on politely emailing them to let them know about their mistakes, I assume its not a malicious mistake, but more the fact that they did not take the time to properly do research. Is there anything else I can/should do?

This morning when I opened my email I was very excited to find a Google Scholar update telling me of two new citations from two different sets of authors each to a different paper of mine. As usual, I immediately checked the papers to find out if the authors were praising or criticising my work (or perhaps they found a mistake in one of my papers!). To my surprise, in one case the authors wrote a misleading statement which resulted from stretching quite a lot some of my conclusions. In the other case, the authors simply made an incorrect claim (details below for the curious). It's not the first time this happens to me - I even got one citation completely out of context once. How to react to this kind of situation?    Details for the curious:   In the first case, the authors cite a paper of mine where I compare two different methods to calculate elastic properties of materials. My main conclusion is that one of the methods converges much faster than the other one with the size of the basis set - in other words, it's computationally much cheaper. For calculations with usual basis sets the first method is much more accurate than the second one, with disagreements between the two in the order of 10% or even 20%. They claim that I show that both methods agree within a 1% of each other, which is misleading at best, because for the second method to agree within 1% of the first one one needs to do a very expensive calculation. That is one of the main points of the paper and it got completely overlooked by the authors. In the second case, the citation is plainly wrong. The authors cite my paper as an experimental work on InGaN semiconductors while it actually is purely computational.


Exception in thread "main" java.awt.HeadlessException: No X11 DISPLAY variable was set, but this program performed an operation which requires it.         at java.awt.GraphicsEnvironment.checkHeadless(GraphicsEnvironment.java:173)         at java.awt.Window.<init>(Window.java:437)         at java.awt.Frame.<init>(Frame.java:419)         at java.awt.Frame.<init>(Frame.java:384)         at sun.applet.AppletViewer.<init>(AppletViewer.java:159)         at sun.applet.StdAppletViewerFactory.createAppletViewer(AppletViewer.java:100)         at sun.applet.AppletViewer.parse(AppletViewer.java:1140)         at sun.applet.AppletViewer.parse(AppletViewer.java:1074)         at sun.applet.Main.run(Main.java:156)         at sun.applet.Main.main(Main.java:98)   I am getting the above error on compiling the file - "HelloWorldApplet.html" in command prompt with the command -   appletviewer HelloWorldApplet.html

I am trying to install a Java application on my Linux machine (Slackware).   I have received the following error, and I do not understand it.   Could you advise me how to approach the problem? Thank you.  Here is what I get: (I see that some X11 DISPLAY variable needs to be set, but what value should I give it and how?)  ~$ java -jar gate-5.0-beta1-build3048-installer.jar - ERROR -  java.awt.HeadlessException: No X11 DISPLAY variable was set, but this program performed an operation which requires it. java.awt.HeadlessException: No X11 DISPLAY variable was set, but this program performed an operation which requires it. at java.awt.GraphicsEnvironment.checkHeadless(Graphic sEnvironment.java:159) at java.awt.Window.<init>(Window.java:407) at java.awt.Frame.<init>(Frame.java:402) at net.sourceforge.mlf.metouia.borders.MetouiaDotsBuf fer.<init>(MetouiaDotsBuffer.java:105) at net.sourceforge.mlf.metouia.borders.MetouiaDots.<i nit>(MetouiaDots.java:66) at net.sourceforge.mlf.metouia.borders.MetouiaToolBar Border.<init>(MetouiaToolBarBorder.java:49) at net.sourceforge.mlf.metouia.MetouiaLookAndFeel.ini tComponentDefaults(MetouiaLookAndFeel.java:241) at javax.swing.plaf.basic.BasicLookAndFeel.getDefault s(BasicLookAndFeel.java:130) at javax.swing.plaf.metal.MetalLookAndFeel.getDefault s(MetalLookAndFeel.java:1591) at javax.swing.UIManager.setLookAndFeel(UIManager.jav a:537) at javax.swing.UIManager.setLookAndFeel(UIManager.jav a:581) at com.izforge.izpack.installer.GUIInstaller.loadLook AndFeel(GUIInstaller.java:373) at com.izforge.izpack.installer.GUIInstaller.<init>(G UIInstaller.java:116) at sun.reflect.NativeConstructorAccessorImpl.newInsta nce0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInsta nce(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newI nstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Construc tor.java:513) at java.lang.Class.newInstance0(Class.java:355) at java.lang.Class.newInstance(Class.java:30 at com.izforge.izpack.installer.Installer.main(Instal ler.java:62)


My approach so far:  Let $x^2+y^2+xy=n^2,$ where $n\in\mathbb Z$.  $\implies (x+y) ^2-xy=n^2$  $\implies (x+y) ^2-n^2=xy$  $\implies (x+y+n) (x+y-n) =xy$  Only one case is possible:  When $x+y+n=xy$ and $x+y-n=1$. On adding, we get: $2(x+y) =xy+1$. Since LHS is an even number so is RHS. That's why, $xy$ must be odd$\implies x$ and $y$ both are odds. So I checked for few odd numbers and found out that for $x=3$ and $y=5,\;x^2+y^2+xy$ becomes $49$ which is a perfect square.. I didn't dare to check for more odds as there could be many...  Recently I found out that for $x=5$ and $y=16$(an even number), $x^2+y^2+xy=361=19^2.$ (Surprising!!)   So now I can say, I am stuck very badly.. All of my observations miserably failed...  Please suggest something!

I have been reading about this quadratic Diophantine equation of the form  $x^2 + axy + y^2 = z^2$  where x, y, z are integers to be solved and a is a given integer.  All integral solutions are given by  $x = k(an^2 - 2mn), y = k(m^2 - n^2), z = k(amn - m^2 - n^2)$ and  $x = k(m^2 - n^2), y = k(an^2 - 2mn), z = k(amn - m^2 - n^2)$  (due to diagonal symmetry in x and y)  where $m,n$ are integers with $\gcd(m,n) = 1,$ but $k \in \mathbb Q$ is rational such that $(a^2 - 4) \, k \in \mathbb Z.$ This is Theorem 2.3.2. on page 90 of An Introduction to Diophantine Equations by Andreescu, Andrica, and Cucurezeranu. (2010). EDIT BY WILL JAGY.  I have no problem understanding how the solution forms were derived; they were just basic algebraic manipulation. But then when it comes to the solutions in positive integers, the form becomes  $x = k(an^2 + 2mn), y = k(m^2 - n^2), z = k|amn + m^2 + n^2|$ and  $x = k(m^2 - n^2), y = k(an^2 + 2mn), z = k|amn + m^2 + n^2|$  where k, m, n are positive integers, an + 2 m > 0 and m > n.  What I can understand is that we apply modulus to the x, y, and z in the previous form to get the latter form (we want x, y, and z to be in positive integers), but I can't seem to understand how an + 2 m > 0 and m > n work to prove  $|x| = |k(an^2 - 2mn)| = kn|an - 2m| = kn(an + 2m) = k(an^2 + 2mn)$ and  $|z| = |k(amn - m^2 - n^2)| = k|amn + m^2 + n^2|$.  Can anyone help me on this? I've been pondering for almost a week. It's driving me crazy. Thank you in advance.


I want to make the footer position at the bottom of the page. My code for footer is...   footer{   height: 80px;   background-color: rgb(93, 158, 255);   color: white;   text-align: center;   position: relative;   bottom: 0; }

Copyrigth &copy;

Designed by:  - Junior Web Development

         Result is

I have the following page (deadlink: http://www.workingstorage.com/Sample.htm ) that has a footer which I can't make sit at the bottom of the page. I want the footer to  stick to the window bottom when the page is short and the screen is not filled, and stay at the document end and move down as normal when there is more than a screenful of content (instead of overlapping the content).  The CSS is inherited and befuddles me. I can't seem to change it properly to put a minimum height on the content or make the footer go to the bottom.


I'm trying to uninstall Ubuntu 14.04 from a dual boot config. I deleted all partitions used by it. There was one partition called OEM partition (A second one, pretty sure Ubuntu made this). I deleted this using EaseUS Partition master.  I made a Windows 8.1 boot USB, used the repair CMD, and tried /fixboot and /fixmbr. I also changed the boot order to windows and deleted ubuntu from the boot order.  I have a strong feeling GRUB's not done with me yet. Is this correct?   The main reason I uninstalled Ubuntu was to make Windows run faster. I do not want to sacrifice on Windows' speed. I do not want to get into technicalities, but how do I remove Ubuntu completely? (This includes everything else it installed : GRUB, GRUB rescue, etc, etc).  I want to remove every last trace of my Ubuntu installation that reduces the performance of Windows.  How can I go about this?

I have installed Ubuntu on my laptop and now I want to remove it and the Grub Loader. How I can do it without the Windows installation disk (I cannot use the Recovery Console).


If I have e.g. 20 lines of text, e.g.
Cheese

Water

Earth

Helicopter

Rabbit
   I wondered if anyone might be able to advise please, how I might be able to have a button on the page which a user can click, which copies the text values to the clipboard, so that all the user gets in their clipboard are the p innerHTML values in a list split by line breaks, e.g.  Cheese Water Earth Helicopter Rabbit   The example above is just a simple example, rather than the finished product I'l be working with, just something to use as an example to demonstrate the point.  I was thinking it might be possible using Javascript / jQuery / accessing the DOM, but I don't know how one would do it.

What is the best way to copy text to the clipboard (multi-browser)? I have tried: function copyToClipboard(text) {     if (window.clipboardData) { // Internet Explorer         window.clipboardData.setData("Text", text);     } else {         unsafeWindow.netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");         const clipboardHelper = Components.classes["@mozilla.org/widget/clipboardhelper;1"].getService(Components.interfaces.nsIClipboardHelper);         clipboardHelper.copyString(text);     } }  But in Internet Explorer it gives a syntax error. In Firefox, it says unsafeWindow is not defined. A nice trick without using :


I would like to remove the first principal component from a data set, but keep that data set in its original coordinates. I have taken a stab at this by taking PCA, zeroing the first PC, and then rotating back using the inverse of the eigvenvector matrix. Is that the most efficient way to do this?  create a sample data set:  set.seed(1234) xx <- rnorm(500) yy <- 0.5 * xx + rnorm(500, sd = 0.3) vec <- cbind(xx, yy) plot(vec, xlim = c(-4, 4), ylim = c(-4, 4))     Take principal components and zero out the first PC:  vv <- eigen(cov(vec))$vectors newvec <- vec %*% vv newvec[, 1] <- 0   Now rotate the new data set back to its original coordinates using the inverse of the PCA rotation matrix:  rvec <- newvec %*% t(vv) # transpose of orthogonal matrix = inverse # plot new points in red and plot eigenvectors in green points(rvec, col = "red") arrows(0, 0, vv[1,1], vv[2, 1], col = "green3", lwd = 2) arrows(0, 0, vv[1,2], vv[2, 2], col = "green3", lwd = 2) legend("topleft", legend = c("original data", "data after extracting PC1", "eigenvectors of original data"), fill = c("black", "red", "green3"))     As you can see it seems to agree with the eigenvector orientations in green. But is this the correct and/or best way? Can I avoid the intermediate matrix multiplications for example?

Principal component analysis (PCA) can be used for dimensionality reduction. After such dimensionality reduction is performed, how can one approximately reconstruct the original variables/features from a small number of principal components?  Alternatively, how can one remove or discard several principal components from the data?  In other words, how to reverse PCA?    Given that PCA is closely related to singular value decomposition (SVD), the same question can be asked as follows: how to reverse SVD?


I am trying to symbolize a road network in QGIS.  Currently I am using a pen width of 1.86 milimeters to symbolize the roads, however I would also like to outline the roads with a secondary color.  This is easily done for polygons, however I cannot figure out if it is also possible with line features.  Another solution would be to use a buffer to generate polygons from the roads, however this is not optimal, so I would like to avoid this.  FINAL EDIT: I do not think this question exactly has been answered before, at least I couldn't find it. However, the answers in the linked questions could also be applied for my case.

I am new to GIS and I am using QGIS 1.7.3 on Windows.  Can any one tell me how to display a map from line shapefile with these two characteristics:   Roads are displayed with borders at the sides and intersect at crossroads Name label for long roads are duplicated at specified intervals   Here is the link to an image that illustrates my idea:    (The map was taken from underdark's blog)  This is the best I can achieve by drawing lines with two overlapping simple line, one slightly bigger than the other:


I'm looking for a cartoon space fantasy film that I saw on TV somewhere between 1985-1988. I think it was a one-off and not a series. I only have sketchy fragments and never got the whole story line, but it involved some form of space travel, quite a few people travelling onboard the vessel, with an old man of some importance who seemed to be comatose. They are trying to save him, I think, and there is some form of relativistic influence occurring, as whatever they are doing, or speed they are travelling at is influencing his age/rate of aging (it might even have been going backward in a parallel dimension). It was quite an intense, serious cartoon, but nevertheless absorbing. There were also a pair of blobby like sub-characters, pale in colour, with arms and legs who tended to drift about and could pick up the character of thought of those around, and may have been made of thought themselves. They had young child-like voices, somewhere around 8-10 years old or so, with UK-English accents. There was a certain electronic music theme that went with them too. That theme has popped up elsewhere, so I doubt it was scored specifically for this. It was aired in the daytime, somewhere mid-morning to early afternoon. The old man was white and had a white beard. The other adult characters spoke in English, and had as far as I remember mildly American- or UK- English accents.

I'm looking for a movie I've seen as a kid, the details are foggy and sparse but I'll try my best following :  What is it?: An animated movie. Tell us what it isn't: It is not . Tell us what made it memorable: A planet where some brain-sucking insect-like aliens live, also an old bald man lives on the same planet. When did you see this film?: Late 80's, early 90's. How old was it?: If I've seen the movie on TV in Spain, is a pretty safe bet that it will be at least 5 years old. Was it part of a series?: I don't think so. Plot: No clue, sorry. What language was it in?: The movie was dubbed to Spanish (Spain).  No detail is too insignificant  What details can I recall?:  Sci-Fi story with one character being an old bald man living on a planet where some insect-ish aliens can open your skull and suck your brain. Habitat of those insect-ish foes was depicted in light blue colors, I kinda remember giant mushrooms as well. A young boy befriends the old baldie, the boy came to the planet with some adults.   Other details I'm not completely sure (maybe my mind is filling the gaps):  I think that the movie was drawn using , not 100% sure though. I cannot remember which year I've seen the movie, but it should be late 80's or early 90's. I'm pretty sure that I've seen the movie in Spanish TV (not rented videotape). Somehow the young boy was the young version of the old baldie (time travel?). The old man lives in a wood house near the brain-sucking insect habitat, as many old man does he spend his time on the porch.    Try to offer unique details As anyone would expect from this kind of movie, there's a scene where the alien insects attack a group of people trying to suck their brains. A young boy was with those adults and survived with injuries in his head. The old bald man have some surgery in his head due to an attack he suffered years before.


I have a complicated structure shown bellow,    This structure is nested, but I need to deep-copy it. My copy function is   export function copy(o) {    if(typeof o==='object' || Array.isArray(o)) return     JSON.parse(JSON.stringify(o));    return o; }   When I use this function to copy the structure, the error shows,  Uncaught TypeError: Converting circular structure to JSON at JSON.stringify (<anonymous>) at copy (util.jsx:50)   Any good ideas about how to copy nested structures? Any suggestions are welcome.

What is the most efficient way to clone a JavaScript object? I've seen obj = eval(uneval(o)); being used, but . I've done things like obj = JSON.parse(JSON.stringify(o)); but question the efficiency.  I've also seen recursive copying functions with various flaws.  I'm surprised no canonical solution exists.


Are there simple/canonical examples for totally real number fields of degree $n$ for any natural number $n \in \mathbb{N}$? Of course, the question can be reformulated by asking if there exists an irreducible polynomial of degree $n$ with real roots only, i.e. all roots in the algebraic closure $\mathbb{C}$ are real.  Currently, I just started to read about field theory, but in the standard books (and soucres) I could not find an answer to my question.   $\mathbb{Q}(\cos(2\pi/n))$ is an example of degree $\varphi(n)/2$. In the Paper  of Ichimura one can find a construction of such polynomials (with some additional properties), using Hilbert's Irreducibility Theorem.    My question arose from Geometry of Numbers/Analytic Number Theory: Any totally real number field gives rise for an 'admissible lattice' $\Lambda$, that means $\inf_{(m_1,\ldots,m_n) \in \Lambda \setminus \{0\}} |m_1 \cdots m_d| >0$ in standard coordinates, as follows. Under the map $\mathbb{K} \rightarrow \mathbb{R}^n$, $x \mapsto (\sigma_1(x),\ldots,\sigma_n(n))$, where $\sigma_1,\ldots,\sigma_n$ denote all embeddings (which are real since $\mathbb{K}$ is totally real) of the number field $\mathbb{K}$, the image of the ring of integers $\mathcal{O}_{\mathbb{K}}$ is an admissible lattice.  Skriganov has shown in  that 'admissible lattices' are very uniformly distributed in parallelepipeds. (The remainder term is only of type $\log^{d-1}{r}$.)

Let $n≥1$ be an integer. I would like to prove (or disprove) the existence of a subfield $K \subset \Bbb R$ such that $K/\Bbb Q$ is Galois and has degree $n$.   It is easy to construct such a subfield for $n=2^k$: one  take $K=\Bbb Q(\sqrt 2, \sqrt 3, \sqrt 5, ..., \sqrt{p_k})\;$ where $p_k$ is the $k$-th prime number.  I found that the irreducible polynomial $x^3-6x+2 \in \Bbb Q[X]$ (Eisenstein's criterion with $p=2$) has three real roots, so its splitting field $K$ satisfies my conditions for $n=3$. Then I'm done with $n=3\cdot 2^k$ thanks to compositum of fields.  , a Galois extension of odd degree must be . In all cases, I don't know how to construct, in general or in particular cases ($n$ prime for instance), such a totally real Galois extension $K/\Bbb Q$ of degree $n$.  Thank you for your help!


How to prove this one? Let $f: R \longrightarrow S$ be a homomorphism of rings $R$ and $S$. If $M$ is a maximal ideal of $S$, then $f^{-1}(M)$ is a maximal iseal of $R$.

Let $\phi:R\to S$ Be a surjective ring homomorphism and $M \subset S$ is maximal, then $\phi^{-1}(M)$ is maximal in $R$. Here is what I wrote (it is known the preimage is an ideal, so prove only maximality)  Assume $\phi^{-1}(M) \subset W \subset R$. Then first $\phi(\phi^{-1}M) = S$ because $\phi$ is surjective. Hence $\phi(\phi^{-1}M) \subset \phi(W) \subset \phi(R) \implies S \subset \phi(W) \subset S \implies \phi(W) = S$. Now let $w \in W$ and $\phi(w) \in \phi(W) = S = \phi(\phi^{-1}M)$, so $w \in \phi^{-1}M$? Or this only shows $x \in \phi^{-1}(M)$ such that $\phi(x) = \phi(w)$?  Is there a way to complete the proof with what I wrote? (I already have witness the solution, basically $\phi^{-1}M \subset R$ is an ideal. Then by isomorphism theorems $S/M \approx R/\ker(\pi \circ \phi)$ where $\pi$ is the quotient map and usually field argument implies $\ker (\pi \circ \phi) = \phi^{-1}M$ because fields contain only two ideals)


i saw some threads about this topic, but no one helps :( I have the following problem, after my ajax i append some li's and img's. I put a class for all my images and after that, my image containers are not clickable. i saw on a thread here that some call to use the jquery live() function, but it doesnt work for me and i tried on() also.  Example:  $('.CLASS').live('click',function(){     alert("LETS ROCK"); });   Here my success Function (Ajax )  for( x in data.data)               {                    if( data.data[x].type == "image" )               {             $('.CLASS ul').append('

');                                            }                 }    thank you in advance

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


I want to show that if $F(T) \in B[T]$, where $B:=k[x_1,x_2,...,x_n]/(x_1^2+\cdots+x_m^2)$, is monic and has a root $\alpha \in\mathcal K(B)$ then $\alpha$ actually lives in $B$. This will imply that $B$ is an integrally closed domain and hence that $\operatorname{Spec} B$ is normal. But I am stuck at this point.  On the other hand, I know that the geometric interpration is that a quadric of $\operatorname{rk} \ge 3$ doesn't have "bad" singularities. Well, I know that such quadrics are irreducible, but that only helps me to show that $B$ is at least an integral domain.

One of the exercises in Ravi Vakil's algebraic geometry notes, Ex. $5.4.$I(b), is to show that    $$ \operatorname{Spec}\left(k[x_1, \ldots, x_n]/(x_1^2 + \cdots + x_m^2)\right) $$   is normal, where $k$ is any field of $\operatorname{char}(k)\neq 2$, and $n \geq m \geq 3$.    I have absolutely no idea how to get started on this. Is there anyone that could give a hint as to how one would approach this problem?


I have got a problem with rendering an animation (eevee). In my viewport everything works fine and the animation looks cool, but when I render it (I have tried to render as png and also as ffmpeg video) everything turns into just white frames. It is totally weird, because during rendering correct frames are appearing, but each frame turns white at the finish of rendering. Do you know what's the reason? :)   That's how rendered frame looks    And that's my viewport

A scene I made is not rendering, at all. This grey screen stays the same and nothing changes.  Here are my settings:  [


I need to write a document with Latex and I installed TexMaker. Does anyone suggest any easier tool? And a good documentation since I am finding loads but I need to learn it as quickly as possible.

Which book (free or otherwise) was the most useful to you when you started learning LaTeX?  I am frequently asked this question by friends who want to learn LaTeX, and I recommend the book which got me started, , but I feel that there might be better options around.  Also see .


How do I regress with regularization penalty term lambda * (w - w0)^2 instead of lambda * w^2? Is there any package to do it?  I produced coef w0 with some old data, now I have some new data, I want to regress again and I want the new coef close to w0.

Here is something I read in Ian Goodfellow's book Deep Learning.  In the context of neural networks, "the L2 parameter norm penalty is commonly known as weight decay. This regularization strategy drives the weights closer to the origin [...]. More generally, we could regularize the parameters to be near any specific point in space" but it is far more common to regularize the model parameters toward zero. (Deep Learning, Goodfellow et al.)  I'm just curious. I understand that by simply adding a regularizing term to our cost function, and that by minimizing this total cost $J$ we can influence the model's parameters to remain small :  $$J(\boldsymbol{\Theta}, \boldsymbol{X}, \boldsymbol{y}) = L(\boldsymbol{\Theta}, \boldsymbol{X}, \boldsymbol{y}) + \lambda||\boldsymbol{w}||_{2}^{2}$$  But how would one implement a version of this regularization strategy that would lead the parameters towards any arbitrary point? (say we want the norm to tend towards 5)


In the various usage of present perfect, I heard that there is a usage of expressing the nearest past like 'I've kicked the dog.' What percentage we used 'present perfect' to express 'the nearest past' in all usage of present perfect?

When we can use "recent past"? How much past time qualifies for "recent past"?


I'm trying to migrate a Ubuntu 19.04 install to the last Ubuntu version. The problem is the migration tool refuses to update to the next version: sudo do-release-upgrade  Checking for a new Ubuntu release Your Ubuntu release is not supported anymore. For upgrade information, please visit: http://www.ubuntu.com/releaseendoflife  Get:1 Upgrade tool signature [1,554 B]                                                                                Get:2 Upgrade tool [1,336 kB]                                                                                Fetched 1,338 kB in 0s (0 B/s)                                                                                authenticate 'focal.tar.gz' against 'focal.tar.gz.gpg'  extracting 'focal.tar.gz'  Reading cache  Checking package manager  Can not upgrade   An upgrade from 'disco' to 'focal' is not supported with this tool.   How can I migrate instead of a fresh install where I would have to reconfigure everything? Thanks in advance for your kind help

I am currently using Ubuntu 10.04. I know there is a 10.10 release, but can I upgrade directly to 11.04? Could you walk me through the steps please?


I understand how friction works in order to accelerate a car. The wheels pushes the road back and this causes a reaction force (friction) to push the wheel forward. My question is how does friction, which acted in the +x direction when accelerating, suddenly switch directions to the -x direction. The wheels are still turning in the same direction as before? How does this work?

I'm unable to understand how friction causes motion in cars and also is responsible for stopping them. When it starts the impending motion of tyres is in the backward direction that's why friction is in the forward direction and the car starts moving. But when the car engine turns off, the car stops after some time, but the condition of tyres are the same as in the previous case and friction must be in the forward direction.


GM,  is log(e) another way of writing ln ? as  $$  log_{(e)}  = ln $$  and consequently when  x=1 $$  log_{(e)}(1+1/2x)  = ln(1+1/2x)  = ln(3/2) =0.405  $$  Please let me know.   Thank you.

$$\dfrac{1}{2}\ln(x+7)-(2 \ln x+3 \ln y)$$  Our professor let's us solve this but i do not understand how $\ln$ works. He says it has same properties with $\log$ but i still don't get it. What's the difference of the two?


When Minecraft updates (It recently updated to 1.8) Minecraft mods no longer work. I have tried setting the Minecraft game back to an earlier version but most of the mods do not work anymore.  Do the mods need to be updated to work with the newest system regardless of updates? Or can mods remain the same and the Minecraft client just need to allow mods to be readmitted into the file system?

I've recently changed to the new Minecraft launcher, and I have noticed a change in the .minecraft folder layout. I can no longer install mods just by copying it over into the versions/1.6.1 jar file, as this file refreshes every time it is launched.  For those who don't know what I am talking about, here is the new layout:    I am specifically trying to install Optifine, which does work with 1.6.1. Where do I drag in the mod files now? I can't seem to find a jar file that is suited to it, except in the version folder, but as I stated above, this refreshes every time.  After copying a recent version and renaming it in the version folder, I get this error in the development console:   Unexpected exception refreshing version list java.lang.IllegalArgumentException: Version '1.6.1' is already tracked     at net.minecraft.launcher.updater.VersionList.addVersion(VersionList.java:91)     at net.minecraft.launcher.updater.LocalVersionList.refreshVersions(LocalVersionList.java:44)     at net.minecraft.launcher.updater.VersionManager.refreshVersions(VersionManager.java:47)     at net.minecraft.launcher.Launcher$2.run(Launcher.java:164)     at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)     at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)     at java.util.concurrent.FutureTask.run(Unknown Source)     at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)     at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)     at java.lang.Thread.run(Unknown Source)


Is there any code for String.Format in javascript as like in vb.net?   val=String.Format("{0:n" & ratedis & "}", to_arr(0))

I'm looking for a good JavaScript equivalent of the C/PHP printf() or for C#/Java programmers, String.Format() (IFormatProvider for .NET).  My basic requirement is a thousand separator format for numbers for now, but something that handles lots of combinations (including dates) would be good.  I realize Microsoft's  library provides a version of String.Format(), but we don't want the entire overhead of that framework.


When I type the same password (jalalkay) it gives me "False" answer!  import java.util.Scanner;  public class password2 {      public static void main(String[] args) {         // TODO Auto-generated method stub          Scanner pass = new Scanner(System.in);           System.out.println("Type a password");         String ps = pass.nextLine();          if(ps == "jalalkay"){             System.out.println("true");          }else{             System.out.println("false");         }      }  }

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


For example, if you're at your BIOS screen or a DOS environment, when you plug in a new USB keyboard, it appears to be usable almost instantly. But, if you are in Windows and plug in a new keyboard, it has to install drivers or updates, making it unusable for the duration. I realize that you don't get full features of certain keyboards in DOS, so Windows has to install drivers for added functionality. But why doesn't the keyboard start working with basic functionality instantly and continue to install the rest of the drivers if needed, obviously the technology is there to make this happen.  This is more for curiosity than to solve a problem, but any insight is appreciated!  Thanks

What does a "Legacy USB Mouse" option in a BIOS mean?  Yes legacy usually means older revision, or obsolete. So legacy usb mouse means support for "old style usb mouses".     That's not really answering the question. As Mr. Tamm, my high school electricity teacher, liked to say, "Yes, and oranges taste orangey."   What does legacy USB mouse support mean?   What is a legacy USB mouse?  There's an "old style" USB mouse?  What changed between what version of usb and what version of usb that made mice incompatible? Why was the change made?  When was the change made? Who made the change? What was the virtue of the "new USB mouses" over the "old USB mouses"?   Put it another way:     What is the BIOS doing when "Legacy USB Mouse" option is enabled?   What is the BIOS doing when "Legacy USB Mouse" option is disabled?   See also


I have recently created my website and hosted it through 000webhost. I have also begun researching on how to make my website 'searchable' from googles search engine.  And so i came across google webmasters and its tools. I created a sitemap and submitted it, and added the needed tags to my website head.  I then asked google to fetch and render my links that i wanted google to have appear when searched for, as shown below:    As soon as it said that my web links were indexed i could search for my website with almost all of my meta tag searches and find it on the two listed pages. A few days later, after using the same search parameters i can no longer find my website, so i went to my index status and it now says that it is currently indexing 0 links as shown below:    I dont understand why this is? and also how can i get my website indexed by google for me to search for it?

It's been sometime and Google has yet to index my site. How can I get Google to index my website?


I have thought of this and looked at other answers but the answer is not clear. We have not learned about Sylow yet and also we have not learned about the kernel.  So far, I know that A5 has order 60 with subgroups of orders 1,2,3,4,5,6,10,12,15,20, and 30. So, I know it must be shown that 15, 20, and 30 are not proper subgroups.  I considered that these subgroups are cyclic but I'm not understanding how this relates to the proof.  Any help is appreciated.

How can it be proved that any subgroup of $A_5$ has order at most 12?  This is [Herstein, Problem 2.10.15], which also gives the hint that I can assume the result of the previous problem that $A_5$ has no normal subgroups $N \ne (e),A_5$.    This problem appears in an earlier section of the text than the Sylow theorems.  There is a proof given at , but it uses the Sylow theorems, and I wonder if a more elementary proof is available.  So far, I can prove the following: For $n \ge 3$, the subgroup generated by the 3-cycles is $A_n$; if a normal subgroup of $A_n$ contains even a single 3-cycle it must be all of $A_n$; $A_5$ has no normal subgroups $N \ne (e),A_5$.  I showed the latter by repeatedly conjugating a given nontrivial element in $A_5$ by 3-cycles to eventually obtain elements whose product is a 3-cycle.


I can’t seem to get the HP OfficeJet Pro 8025 to scanning Linux regularly. The scanning seems to work only sporadically, even though the unit is detected in Ubuntu. I tried installing the HPLIP software, but the install does not succeed in Ubuntu 20.10, something related to Python dependencies not being met. The HPLIP software uses simple-scan for scanning documents. The simple-scan software sometimes works, but a lot of the time the scanning seems to be sporadic. I am using a USB connection and the lsusb command seems to detect the printer/scanner combo fine. Printing with CUPS almost works every time; I only had an issue where the printer wouldn't print once.

Let's assume that one has some modern HP printer and/or scanner which is  supported by HPLIP package from official repository. Or supported by newer version of HPLIP package (see  about installation).  From official documentation () it is known that device needs proprietary/binary driver or plugin.  How should one install such plugin?


Prove that if $|f| + |g| \equiv c$ ($c\in \Re$) in set $Ω\subseteq C$  where $f,g$ holomorphic in Ω then $f\equiv a$ , $g\equiv b$ where $a,b\in C$. Well the real problem was to show it for $\sum_{i=1}^{n}|f_{i}| \equiv c$ but I think i should starting by proving it for 2 of them.(This was once given to us on an exam as the only problem in it and it was valuated with 100% of the grade)

Let $D\subseteq \mathbb{C}$ be open and connected and    $f,~g:D \rightarrow \mathbb{C}$ holomorphic functions such that    $|f|+|g|$ is constant on $D.$ Prove that $f,~g$ are constant on $D.$   Attempt. I noticed first that this problem is already set before, and is considered  to be duplicate () and we are sent directly to problem . However, the last reference deals with the sum $|f|^2+|g|^2$, which I do not see how is connected to the sum $|f|+|g|$, as stated in our title (for example, the equality $|f|^2+|g|^2=(|f|+|g|)^2-2|f||g|$ is not helpful here).  Thanks in advance!


I was wondering if it is possible to modify what values show up in the Chrome omnibox when typing certain phrases.  For example, when I start typing "basecamp" it goes to basecamp.com/#####/projects/#####-old-project-im-not-on. I'd like it to either not have this one show up at all or instead prefer basecamp.com/#####/projects/#####-brand-spakin-new-project-yay.

I accidentally visited gist.gihub.com (note the missing t), and now that URL auto completes each time I start typing gist.…. How can I remove this URL?  I've tried removing it from my history, but that doesn't help:     (note the empty search results)


I have my win10 and various apps installed on my HDD. And I have a new SSD. Is there a way to safely move win10 to the SSD? Or the only way is to install it again?

Is there a free way to clone a full Windows 7 installation from HDD to SSD? (The free part is important, I know I can pay for Acronis True Image.)      SSDs are usually much smaller than HDDs which complicates matters. For instance, I have about 50GB data, my new SSD is 80GB but I still can't use Windows clone/restore system if my HDD is something like 300GB.  Therefore, I'm looking for a third party tool that will be able to:   Create a clone of my C: partition Store it onto an external USB drive Boot from some rescue / restore CD Load the image onto the new SSD   Acronis True Image seems like a tool that should support this but it's a paid-for software and the trial version cannot create clones. Acronis Migrate Easy is a fully functional tria for 15 days but need both the HDD and SSD connected at the same time which is a bit of a problem for me as a laptop user.  P.S. I almost got there combining Windows image backup combined with Acronis True Image restore CD (which can load .vhd's) but was not able to boot as some boot information were probably lost and could not be repaired using the Win7 installation DVD.


index.php  <!DOCTYPE HTML>

       check.php  check   I am loading some extra html into my index page , but i can't call any div or a jQuery from index page. i know is because it load the html after the page was done and i call before that.  But even I put $('.masterTooltip').hover inside $(window).load it won't work. My question is how can i call those those div or a from index ? but without putting those jQuery at check.php ?  If i put those jQuery code at check.php it work.

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


I have database "raj" with table "pagination"  In table pagination have "id", "actualtime" and "created" field  id - auto_increment actualtime- varchar created- datetime  that looks like this CREATE TABLE pagination(     id int auto_increment,     actualtime varchar(55),     created datetime )  I want to display all rows which are created on todays date and will display from today upto yesterday at 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 display value after 06:00 pm on yesterday but i want to display all data before 06:00 pm from currentdate.  After 06:00 pm data will be refreshed and clear. plz help me......  SELECT actualtime  FROM pagination  WHERE created BETWEEN date_add(date_sub(curdate(), INTERVAL 1 day), INTERVAL 18 hour) AND curdate()";

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)        ";


How do I show that an entire function $f(z)$ that satisfies $$ |f(z)|\leq\frac{1}{|Im(z)|} \quad \forall z\in\mathbb C $$ is a constant function?

Let $f(z)$ be an entire function such that $$|f(z)|<\frac{1}{|\text{Im}(z)|},\qquad z\in\Bbb C-\Bbb R.$$ The question asked me to prove that $f(z)=0$. At least looking at it, it really seems to have an application of Liouville's theorem lurking around somewhere, but I haven't found it.   My thoughts first led me to think about doing this by contradiction and using Picard's little theorem. So, I've considered a strip containing the real axis (say of width $2$ for simplicity). This will imply the complement maps into the unit disk, which implies that this strip has to map almost everywhere else on the complex plane. Now, on the imaginary axis, I know that $f(z)$ will vanish as $z\to\infty$, and this seems like it might be useful. I'm sort of under the impression $f(z)$ might have an essential singularity at $\infty$, which would mean $f(1/z)$ has an essential singularity at $0$. Either way, it of course can't have a pole at $\infty$ because of $f(z)$ vanishing on the imaginary axis, and if it is a removable singularity, it must be $0$, which still gives the solution. Therefore, I think it must have something to do with $f(z)$ having an essential singularity at $\infty$.   I was hoping to combine this with the above inequality and deduce a contradiction, but I haven't thought of one yet.   Any hints or suggestions? I'm studying for a prelim. exam, so this isn't homework.  Update: So, in the spirit of searching methods using the essential singularity at $z=0$, we have $$\left|f\left(\frac{1}{z}\right)\right|\leq\frac{1}{\left|\text{Im}\left(\frac{1}{z}\right)\right|}=\frac{|z|^2}{|y|}.$$ Thus, for $|y|>1$, we have $$\left|f\left(\frac{1}{z}\right)\right|<|y|\left|f\left(\frac{1}{z}\right)\right|<|z|^2.$$ Thus, if I can show that $|f(1/z)|$ is a polynomial, we'll know it can't have an essential singularity at the origin, concluding my proof.


When hunting down treasure goblins, like the , it drops items periodically.  If I leave it living, just ensure I damage it enough once it tries to escape through a portal, will my net reward from such a goblin be affected?  Meaning, does each such goblin have a fixed amount of reward to drop, or does it have some like that + that periodic drop?  If the latter, then perhaps the longer I can keep it living but keep it from escaping, the higher my total reward would be?

Every once in a while I'll come across the sneaky devils and they always flee.  What determines when they flee (time, distance, etc.) and do I get better loot by killing them faster?  Is there anything else I should know in order to get the most out of the encounter?  EDIT: What I mean is: Is the final drop better based on how effectively I defeat them?


i'm 100% positive this has been asked before. but ive wasted most of my day off and i can't find any straight answers for my problem... I need Unix/Linux on my computer to run some astronomy programs. I have a 1TB HDD and a 150gig, my 1TB has windows and everything on it. i want to install ubuntu on the 150gig so all i have to do is boot from the separate hard drive and everything i do in ubuntu is on that 150 gig. keep everything separate. but every time i try to install it i get problems.  To list a few, I got an ISO i received no information on how to use. i used the application saying i needed to insert a CD. i don't have a cd. i clicked the "i cannot boot from CD" option and spend 30 minutes waiting for it to do something. and installed a trial version. or something. i went to install the full version and it wasn't reading the 150 gig. HD.  I got a bunch of restarts with "cannot find an OS" and had to manually reboot from the 1TB, my computer not reading my USB to install from usb. and a bunch of other stuff  TL;DR I wan't to know how to make an installation USB drive that will let me INSTALL Ubuntu on a second hard-drive i have. Not Run off the USB in a virtual window. which is another problem that i had when trying to get an installation usb

I would like to see a full how-to guide on how to install Ubuntu.


Let $\mathbb{Q}$ denote the set of rational numbers. Find all functions from $\mathbb{Q}$ to $\mathbb{Q}$ which satisfy    $f(1)=2$; and  $f(xy)=f(x)f(y)-f(x+y)+1$.   I know that $f(x)=x+1$ satisfies the equation but I don't know how to prove if this is the only such function. This question was in the 'Induction' section of my textbook.   Any hints?

Define a function $f\colon\mathbb{R}\to\mathbb{R}$ which satisfies $$f(xy)=f(x)f(y)-f(x+y)+1$$ for all $x,y\in\mathbb Q$. With a supp condition $f(1)=2$. (I didn't notice that.)  How to show that $f(x)=x+1$ for all $x$ that belong to $\mathbb{Q}$?


I am using a dedicated server hosting for one of my project. I got a mail from my server provider that their monitoring system noticed a network scan (or network attack) from an IP address. The Netscan output they send to me is something like this   Sun Mar 16 09:57:21 2014 TCP my_server_ip 63624 => attacker_server_ip_1 5038 Sun Mar 16 09:57:21 2014 TCP my_server_ip 63624 => attacker_server_ip_2 5038 Sun Mar 16 09:57:21 2014 TCP my_server_ip 63624 => attacker_server_ip_3 5038  Sun Mar 16 09:57:21 2014 TCP my_server_ip 63624 => attacker_server_ip_4 5038    and so on ....  The attacker has used multipal ips probablity more than 200 ip. Please guide me what attack is all about and what should i do to avoid this attack.  Many many thanks in advance

This is a  about Server Security - Responding to Breach Events (Hacking)   See Also:                  Canonical Version I suspect that one or more of my servers is compromised by a hacker, virus, or other mechanism:   What are my first steps? When I arrive on site should I disconnect the server, preserve "evidence", are there other initial considerations? How do I go about getting services back online? How do I prevent the same thing from happening immediately again? Are there best practices or methodologies for learning from this incident? If I wanted to put a Incident Response Plan together, where would I start? Should this be part of my Disaster Recovery or Business Continuity Planning?   Original Version       2011.01.02 - I'm on my way into work at 9.30 p.m. on a Sunday because our server has been compromised somehow and was resulting in a    attack on our provider. The servers access to the Internet   has been shut down which means over 5-600 of our clients sites are now   down. Now this could be an FTP hack, or some weakness in code   somewhere. I'm not sure till I get there.      How can I track this down quickly? We're in for a whole lot of   litigation if I don't get the server back up ASAP. Any help is   appreciated. We are running Open SUSE 11.0.            2011.01.03 - Thanks to everyone for your help. Luckily I WASN'T the only person responsible for this server, just the nearest. We managed   to resolve this problem, although it may not apply to many others in a   different situation. I'll detail what we did.      We unplugged the server from the net. It was performing (attempting to   perform) a Denial Of Service attack on another server in Indonesia,   and the guilty party was also based there.      We firstly tried to identify where on the server this was coming from,   considering we have over 500 sites on the server, we expected to be   moonlighting for some time. However, with SSH access still, we ran a   command to find all files edited or created in the time the attacks   started. Luckily, the offending file was created over the winter   holidays which meant that not many other files were created on the   server at that time.      We were then able to identify the offending file which was inside the   uploaded images folder within a  website.      After a short cigarette break we concluded that, due to the files   location, it must have been uploaded via a file upload facility that   was inadequetly secured. After some googling, we found that there was   a security vulnerability that allowed files to be uploaded, within the   ZenCart admin panel, for a picture for a record company. (The section   that it never really even used), posting this form just uploaded any   file, it did not check the extension of the file, and didn't even   check to see if the user was logged in.      This meant that any files could be uploaded, including a PHP file for   the attack. We secured the vulnerability with ZenCart on the infected   site, and removed the offending files.      The job was done, and I was home for 2 a.m.            The Moral   - Always apply security patches for ZenCart, or any other CMS system for that matter. As when security updates are released, the whole   world is made aware of the vulnerability.   - Always do backups, and backup your backups.   - Employ or arrange for someone that will be there in times like these. To prevent anyone from relying on a panicy post on Server   Fault.


Is there any way I can query the Resources in Public Calendars and Resources? There does not seem to be any object related to the resources so if someone could help me out, it'd be great!

I want to add event to public Calendars using Apex code in trigger. Currently I have hardcoded id of public  Calendar in my code. But I don't want to hardcode id of Calendars. I want to query it in my code. But I am not able to query it as it says sObject type 'Calendar' is not supported.  Any help is appreciated.  Thanks Ankush


Show that the following are equivalent for a ring:  (1) any $R$-module is projective.  (2) any $R$-module is injective

I am solving an exercise from Dummit, Foote. Let $R$ be a ring with $1$. Then the following are equivalent:   Every $R$-module is projective. Every $R$-module is injective.   Proof:  (1) implies that for any R-mod $A$ we have $Ext^i(-,A)$ is a zero functor. But this means that for any R-mod $Ext^i(L,A) = 0$ for all $A$ so $L$ is injective. I show $(2) \Rightarrow (1)$ exactly the same way.  It is quite easy so I am afraid I missed something. Is my proof correct?


Let $\mathbb{F}_q$ be a finite field with $q=p^f$ elements. I know that for each $0\leqslant i\leqslant f-1$, the maps $\sigma_i(x)=x^{p^i}$ are $\mathbb{F}_p$-automorphsim of $\mathbb{F}_q$ (so $\sigma_i(x)=x$ for every $x\in \mathbb{F}_p$). Are there any other $\mathbb{F}_p$-automorphsim ? My Attempt: suppose that $g$ is a generator of $\mathbb{F}_q$. If $\sigma$ is an $\mathbb{F}_p$-automorphsim, then there exist a positive integer $k$ such that $\gcd(k,q-1)=1$ and $\sigma(g)=g^k$. Does $k$ must be a power of $p$ ?

I have to compute Galois group of $\mathbb F_q/\mathbb F_p$ where $q=p^n$. I know already that $\mathbb F_q/\mathbb F_p$ is galois, so I don't need to prove it. Moreover, I know that \begin{align*}\sigma :\mathbb F_q&\longrightarrow \mathbb F_q\\ x&\longmapsto x^p\end{align*} is an automorphism that fix elements of $\mathbb F_p$ and thus $\sigma \in Gal(\mathbb F_q/\mathbb F_p)$.  Now, I know that if $k<p^n$ then $\sigma ^k(x)=(x^{p})^k=x^{pk}\neq 1$ and thus $\sigma $ is of order $p^n$. Now if I can prove that $|Gal(\mathbb F_q/\mathbb F_p)|=p^n$, then $Gal(\mathbb F_q/\mathbb F_p)=\left<\sigma \right>$ and it would be finish, but I can't prove it since even $X^q-X$ split over $\mathbb F_q$, theis polynomial is not irreducible, and thus, I can't conclude. So how can I find an irreducible polynomial of degree $q$ that split over $\mathbb F_q$ ?


I have a folder having multiple geodatabase and I am calling that folder “Multiplegdb” There are 3 geodatabase in a folder which are as follows:   ABC.gdb UVW.gdb XYZ.gdb   Each geodatabase have several ‘Feature Dataset’ and each ‘Feature dataset’ have several ‘Feature Classes’.  My task:  I would like to list all the features datasets and feature classes in each geodatabase in a folder into CSV. I also would like to get the metadata information from each feature class into CSV file. The format of CSV file will be: GDB Name, Feature Dataset Name, Feature Classes name, Summary, Descriptions, Credits, Date Modified, File path.

I need to create a metadata-table for all files in a File Geodatabase.   Is it possible to automatically be updated with new filenames, and possibly even metadata (as created in the ArcGIS metadata editor)?


For the purpose of a startup, I have a loan for one physical dedicated server with several virtual machines inside it   For now there is mainly 2 VM on this server:  VM "tools", using ubuntu server 10.04 LTS   A source code repository using mercurial and hgserve A bunch of JAVA app for Atlasian for bug tracking, wiki... PostgreSQL as the Database for the tools Apache HTTPD as HTTPS front end.   VM "asterisk", using ubuntu server 10.04 LTS   with an asterisk server, functionnal, but more for testing as of now than anything.   But in the future we will have a "production" VM with ou JAVA application :   Apache HTTPD frontend  PostgreSQL database Tomcat webapp (maybe cluterised)   What I'am interrested into is a software that can monitor availability of services, KVM VM, applications and database so I can react in case of problem.  I have also another use case where I'd like to monitor the performance of the application (request, CPU, memory...) and gather usage statistics.  We have basically no money, and want a free tool, at least at first.   What would be easy and simple tool for the job ? I have heard of Nagios and Hyperic but I don't know them. So I don't know if they are suited for our needs.  EDIT :  The need is not only for server monitoring but also as a way to investigate actual application perfornance, responsiveness and if possible isolate bottlenecks.  From the links (not the same question as it seem more generic but quite informative) and the actual responses, Nagios + Munin should be a good fit. Problem is Nagios seems a little complex (I don't know for Munin). Will the Nagios/Munin combo will be able to gather detailled statistics and historical data for a java application (request/seconds, request latency, both with statistics by URL, hour, day, week... ?)  Are there other (better ?) alternatives ?

For a more comprehensive list of monitoring tools and their features, check out .   As the question states, what are the most commonly used tools used for this task and what are their strengths and weaknesses?


Are there any statistics that would show changes in voting patterns across SE sites since there was a change in the reputation system rewarding question upvotes with 10 points?  I am asking about voting patterns - numbers of votes cast up or down, not impact on users' reputation.   There are few possible outcomes:   Nothing has changed; voting counts on questions have not significantly changed There are more upvotes cast to questions There are more downvotes cast to questions   Are there any significant differences between different sites?

seems to be the opposite of . Back then,  included a nice analysis of what the effect would be when this change occurs.  I think it would be nice to have an impact analysis (something more substantial than the askers will gain more reputation which is quite obvious).  A particular point of this analysis would be the following case (questions):   score < 0 current reputation gained by user from the question < 0 new reputation gained by user from the question > 0   If there are many such cases, it would significantly encourage asking bad questions.  Question: Is there any impact analysis being done for the question reputation change similar to the one done in the past?


I was just wondering if you have two passports (a Chinese one and an Australian one), and you booked your airline ticket with the Chinese one, will you have to show both of your passports or just one?  The thing is, on my Chinese passport, it has my birth name, but then when I became an Australian citizen, I legally removed my Chinese name and replaced it with my English name. So I don't know whether I should just show the passport officials the one that I booked the airline ticket with.

I am a citizen of two different countries, and have two passports.  How should I use my passports when traveling?


I haven't had any good ideas nor found any helpful identities so far, so I'd appreciate some help.  Also, here $m > 2$.  Update: Thanks to the hints and to  previous post I managed to get to the conclusion I wanted. Thanks guys.

How can we sum up $\sin$ and $\cos$ series when the angles are in arithmetic progression? For example here is the sum of $\cos$ series:  $$\sum_{k=0}^{n-1}\cos (a+k \cdot d) =\frac{\sin(n \times \frac{d}{2})}{\sin ( \frac{d}{2} )} \times \cos \biggl( \frac{ 2 a + (n-1)\cdot d}{2}\biggr)$$  There is a slight difference in case of $\sin$, which is: $$\sum_{k=0}^{n-1}\sin (a+k \cdot d) =\frac{\sin(n \times \frac{d}{2})}{\sin ( \frac{d}{2} )} \times \sin\biggl( \frac{2  a + (n-1)\cdot d}{2}\biggr)$$   How do we prove the above two identities?


Its a South Korean animation TV series called ''Spheres'' and it is has strong similarities of Japanese animation techniques used in the series and art style that looks similar to anime        Should we regard this as anime like Japan's due its animation styles and techniques that Japanese use and despite being an animation of non Japanese origin?

is created outside Japan but is called Anime officially, can a cartoonic show created outside Japan be called anime?   the official trailer by the official account of the studio on YouTube,  in the description it officially states that it is an Anime.


Consider the initial value problem   $$xu''+\sin(x)u=0 \ \ \ \ u(0)=0, u'(0)=2$$   Derive the first $4$ non-zero terms of a power series solution to this problem about the point $x=0$.    I know the solution will have the from $$u(x)=\sum_{k=0}^{\infty}A_kx^k$$ But upon differentiating, I get that $$\sum_{k=0}^{\infty}k(k-1)A_kx^{k-2}+\sin(x)\sum_{k=0}^{\infty}A_kx^{k-1}=0$$ and do not know how to proceed. Would an initial substitution help?

Consider the initial value problem   $$xu''+\sin(x)u=0 \ \ \ \ u(0)=0, u'(0)=2$$   What can be said about the radius of convergence of this series?   I have determined that the first four nonzero terms (about the point $x=0$) of the power series are $$2x,-x^2,\frac{1}{6}x^3,-\frac{1}{72}x^4$$ How can I test for convergence? Intuitively it looks not to converge, but how can I  show this?  edit  The solution will have the from $$u(x)=\sum_{k=0}^{\infty}A_kx^k.$$ Differentiating, \begin{align} \sum_{k=2}^{\infty} k(k-1)A_kx^{k-1}+\sin(x)\sum_{k=0}^{\infty}A_kx^k&=0 \\ \sum_{k=2}^{\infty} k(k-1)A_kx^{k-1}+\left(\sum_{k=0}^{\infty} \frac{(-1)^k x^{2k+1}}{(2k+1)!}\right)\sum_{k=0}^{\infty}A_kx^k&=0 \\ (2A_2x+6A_3x^2+12A_4x^3+20A_5x^4+30A_6x^5+42A_7x^6+..)+\left(2x^2+A_2x^3+\left(A_3-\frac{1}{3}\right)x^4+\left(A_4-\frac{A_2}{6!}\right)x^5+\left(A_5-\frac{A_3}{3!}+\frac{2}{5!}\right)x^6+..\right)=0 \end{align} Equating coefficients, $x^{2k}=0$ for $k\in\mathbb{Z^+}$. $$6A_3+2=0\implies A_3=-\frac{1}{3}$$ $$20A_5+A_3-\frac{1}{3}=0\implies A_5=\frac{1}{30}$$ $$42A_7+A_5-\frac{A_3}{3!}+\frac{2}{5!}=0\implies A_7=-\frac{19}{7560}$$ Hence $$u=2x-\frac{1}{3}x^3+\frac{1}{30}x^5-\frac{19}{7560}x^7+..$$


So I've been playing a lot of hardcore minecraft lately, it's fun to need to be careful. Unfortunately an out of game event occurred that needed my immediate attention, which lead to my death in game. I've still got the save file, but when I log in a see the "You are dead" screen:  Not actually from me, just for explanation purposes.  I'm comfortable editing the files with NBTExplorer but I'm not sure which files to edit. I died in the nether, but I've managed thus far to move myself to my spawn points in the overworld and give myself 19 hp. But I'm still dead. Any advice? I'd like to keep the game in hardcore mode if possible!

My brother jumped into the voice of the doom in my Hardcore Creative map. I didn't press the ΄΄Delete This World΄΄ button yet.


I reviewed some late answers and found some that weren't answers. They were either comments to other answers or questions about the same/similar issue in a "forum-style". All of them were from new users with only 1 rep.  I wrote a comment to every answer, explaining those users what they did wrong and what they should do instead and flagged the answer afterwards as "Not an answer".  So the Mods reacted quite quick and deleted all of those answers. When I now visit the profile of those new users, its absolutely blank. No answer, no comments, ...  I am not sure if they will be ever be notified about my comments and if they want to go to their answers, they have to search them without having a clue about what happened (I assume they will still see them when they find the question again).  My idea was to teach them, that they have a chance to do better next time, but this seems a bit useless to me now, or are they informed in some way that their answer has been deleted and where to find them?

When I flag new user posts for "Not an answer" or "me too" type stuff, I usually write a comment to the user asking him to post a separate question  and don't pollute the universe bla bla.   Now I can see later - the post was deleted by a mod, but will the OP receive my comment if he logs in after a while - since the post is deleted.  Examples (I assume 10Ks can see the deleted posts - I'm not sure if these are the ones I commented on, but I flagged these for deletion)   or


As requested, I am forking a question as continuity to my previous inquiry from:    As such, this is not a duplicate. It is done so that the progrssion of the discussion is not so hard to follow for the readers. Maybe you should start doing it here in SE -- linked posts.    Keysight DC Sweep Problem  Alright, so I here's the DC sweep from the problem of the previous post above. I'm not really sure if I set it up right, since I'm new with ADS.  Here's the new setup:   Here's the output:    Doesn't seem to matter what I initialize VINMAG to be, it shows the identical plots. I can ignore VOUT for now, but why is VINMAG's plot always the same for any initialization? Probably a problem with variable declaration/initialization?  This can't be right.

For those of you that uses Advanced Design System (ADS), from this circuit:   Fundamental Frequency for transient simulation tool is set to 1GHz.  Yet, I'm getting this output:   Main question:  Since this is Common Drain, VOUT should at most have the same amplitude as VIN. Probably even negative shift, since I didn't change the voltage threshold (I haven't got to tweaking parameters yet). So what's up with the positive DC bias?? Why is the amplification significantly less than unity?  Other questions:  1.) Also, what's that Transient Response at the very first cycle of VOUT? Why would a semiconductor have a Transient Response? Is it because of the "inductance" on the drain and source of a MOSFET?  2.) Lastly, why is it that this simulation does not work on very low frequencies? I first started with 1Hz scale for everything (just change all units from 1GHz below to 1Hz). The M1 just acted like a 1kOhm constant resistor.  UPDATE:  Because of recent response, I bothered to simulate this in the 1kHz scale (replaced all units from GHz in the pics to kHz, did the same with Fundamental Frequency) -- really should've done that in the first place (stupid me). This is the output:    Even here, the DC bias is nearly the same and the amplification is much, much less. It also lags by 90°. Why?  I'm starting to think it's either just using the wrong component or there was a set of parameters to fill-in for this component to get this to work.  UPDATE:  the continuation of this discussion: