There is a person in my current daily life who never admits his wrongs. He is always quick to blame others first and always believes that he is not wrong. Even when he is proven wrong, he still believes he shouldn't be sorry and isn't wrong.   Is there a single-word adjective to describe this behavior? If not, a better way to describe this person would also make do.   While stubborn and irresponsible fit, I feel like they don't tell the whole story. By this, I mean if I were to say to others that he is very stubborn and irresponsible, it is not implicitly implied that he blames others and never acknowledges his own fault.  Edit: I believe my question is different because the person will also never acknowledge their wrongdoing. On top of blaming others, even after it has been proven to be their fault, they will not admit wrong doing. So aside from blaming others, they refuse to acknowledge the possibility that they have committed a mistake.

No matter what had really happened, this person will always blame and find an appearing logical/thought out way/strategy to it that, fundamentally, it's the other person who was the cause for all the trouble AND everything else that came from this trouble as well and from the next and so on.  No (slang) words like "jerk", "*sshole" etc. please.


I don't want the symbols to show up on my resume. I would like to input simple text containing my email address, phone number and linkedin URl.

I'm writing up my resume right now. My code looks like this:  \name{}{John Doe}   \email{John_Doe@gmail.com} \mobile{839-839-8399}   and the output currently looks like this:    But when I add \homepage, the symbol pops up, as following:    Is there a way to remove the home symbol?


So, I am planning on buying a new headset and the 3.5mm jack wire is both audio and microphone in one. I am unable to find out whether my case and/or motherboard supports this kind of wire.  Q1: What are these 'two-in-one audio/mic' 3.5mm jack cables called?  Q2: Which specification would I have to check (now, and in the future) to check for support?

I am ordering a Logitech headset that has separate audio and mic connectors. My laptop only has one 3.5mm audio port.  How can I tell if my laptop audio port works with a microphone? I am in the process of purchasing an audio adapter to convert 2 inputs to 1 input for the laptop, but I need to check if the one on my laptop works with a mic.


What verb, phrase or phrasal verb do you use when you are waving your hand to scare off or kill a fly? Can I say swat at? For example:  I swatted at a fly for hours with no success.  I am sure there are others phrases, but I can't remember it. It sounds like spat away or bat away.

I am looking for a word that means similar to driving out (a fly), so you 've got a fly or a bird flown into your home and you want to chase it out. It sounds like swish or woosh something. Does Anyone have any idea?


I use MAMP on Mac.  When I try to use drush en omega command on drupal root directory to install omega, But the terminal throw me an error:   drupal-7.23 tangmonk $ drush en omega  Command pm-enable needs a higher bootstrap level to run - you will   [error] need to invoke drush from a more functional Drupal environment to run this command.  The drush command 'en omega' 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.  Drush was attempting to connect to:  Drupal version         :  7.23  Site URI               :  http://default  Database driver        :  mysql  Database username      :  root  Database name          :  drupal  Default theme          :  garland  Administration theme   :  garland  PHP executable         :  /usr/bin/php  PHP configuration      :  PHP OS                 :  Darwin  Drush version          :  7.0-dev  Drush configuration    :  Drush alias files      :  Drupal root            :  /Users/tangmonk/Sites/drupal/drupal-7.23  Site path              :  sites/default  File directory path    :  sites/default/files      * 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     http://drupal.org/node/1428638 for details.   It seems mysql issue. But my site run perfect.

After much trial and tribulation, I thought I had drush all ready to roar. Much excitement. But then, no joy...  Drush is working. The sites operate fine via MAMP. Regardless, a "drush cc all" command returns:   No Drupal site found, only 'drush' cache was cleared.                                          [warning] 'all' cache was cleared.                                                                       [success]   This question has stumped drupalcon attendees and very experienced developers. Any ideas?  I am on Mac OS 10.9.3 using MAMP (free) Version 3.0.5  Here is my drush status:   Drupal version         :  7.29-dev                                 Site URI               :  http://default                           Database driver        :  mysql                                    Database hostname      :  localhost                                Database username      :  db_user                             Database name          :  db_name                        PHP executable         :  /usr/bin/php                             PHP configuration      :                                           PHP OS                 :  Darwin                                   Drush version          :  7.0-dev                                  Drush temp directory   :  /tmp                                     Drush configuration    :                                           Drush alias files      :                                           Drupal root            :  /Applications/MAMP/htdocs/mysite.dev   Site path              :  sites/default       Have tried executing drush from /Applications/MAMP/htdocs/mysite.dev; from /Applications/MAMP/htdocs/mysite.dev/sites/default; and using drush cc all --uri=http://localhost/mysite.dev  Tried running drush from sites/default. Same result.


I need to draw a binary tree (in fact the Stern-Brocot tree) with two pseudo nodes as parents to the root, as seen in the first picture.  At the moment I'm using tikz to draw it but the two pseudo nodes are all the way on the left. (See second picture) How can I align them or is there another completely different, better aproach?  The code I'm using: \begin{figure}     \centering         \begin{tikzpicture}             \tikzset{                 level 1/.style={level distance=15mm,sibling distance=65mm},                 level 2/.style={level distance=15mm,sibling distance=30mm},                 level 3/.style={level distance=15mm,sibling distance=15mm},                 level 4/.style={level distance=15mm,sibling distance=10mm},             }             \node {$\frac{1}{1}$}             child[grow=up, left] {node {$\frac{0}{1}$} edge from parent[dashed]}              child[grow=up, right] {node {$\frac{1}{0}$} edge from parent[dashed]}              child {node {$\frac{1}{2}$}                 child {node {$\frac{1}{3}$}                     child {node {$\frac{1}{4}$}}                     child {node {$\frac{2}{5}$}}                 }                 child {node {$\frac{2}{3}$}                     child {node {$\frac{3}{5}$}}                     child {node {$\frac{3}{4}$}}                 }             }             child {node {$\frac{2}{1}$}                 child {node {$\frac{3}{2}$}                     child {node {$\frac{4}{3}$}}                     child {node {$\frac{5}{3}$}}                 }                 child {node {$\frac{3}{1}$}                     child {node {$\frac{5}{2}$}}                     child {node {$\frac{4}{1}$}}                 }             };         \end{tikzpicture}     \caption{...} \end{figure}


I am confused in some part of the proof. Let $A =[\bar{a_1} \bar{a_2}\dots\bar{a_n}]$. Suppose, rank($A$) < $n$ then there is a $k$ such that  $$a_k = \sum_{i=1}^{k-1}\alpha_{i} \bar{a_i}$$   Now suppose $(x_1, x_2,\dots,x_n)$ is a solution. Then we can generate another solution vector where the first $k-1$ terms are $(x_i + \alpha_i x_{k})$ where $i=1,2,\dots,k-1$, the $k$-th term is $0$ and the rest of the terms are as it is. Now, if $x_k$ is non-zero I am getting two different solution vectors, thus getting contradiction, but if $x_k$ is zero in the original solution we get the same vector by our construction process. So, how to get a contradiction ?

Theorem: Given a system of linear equations $Ax = b$ where $A \in M_{m \times n}\left(\mathbb{R}\right)$, $ x \in \mathbb{R}^{n}_\text{col} $, $ b \in \mathbb{R}^{m}_\text{col}$ Deduce that a solution $x$ exists if and only if $\operatorname{rank}\left(A|b\right) = \operatorname{rank}\left(A\right)$ where $A|b$ is the augmented coefficient matrix of this system  I am having trouble proving the above theorem from my Linear Algebra course, I understand that A|b must reduce under elementary row operations to a form which is consistent but I don't understand exactly why the matrix A|b need have the same rank as A for this to happen. Please correct me if I am mistaken


What does this syntax mean in python? Why after assignment is slash ? discriminator_on_generator= \     generator_containing_discriminator(generator,discriminator)

I have a long line of code that I want to break up among multiple lines. What do I use and what is the syntax?  For example, adding a bunch of strings,  e = 'a' + 'b' + 'c' + 'd'   and have it in two lines like this:  e = 'a' + 'b' +     'c' + 'd'


If I kill all the policemen in the police station with the alarm activated will it prevent me from continuing the game?   What about other repercussions?

There are many innocent civilizians in Deus Ex: Human Revolution. Assuming I don't do so in sight of a police officer, are there any consquences to killing civilizians, or am I free to soak Detroit red with the blood of its people?


$$ \int_{-\infty}^{\infty} \frac{dz}{(z^2+a^2)^2}$$ Now this has the poles at  $$(z^2+a^2) = 0 $$  if we consider the contour from -R to +R extending from $-\infty$ to $+\infty$ i get the roots  $z = ae^{i\pi/2},ae^{i3\pi/2}$ that lie in the contour Now how to find the residues of these poles ??

Find $$\int_{-\infty}^{\infty}\frac{1}{(x^2+b^2)^2}dx$$   We see that the only poles are at $x=\pm bi$.  Integrating over the semicircular contour implies that it is equal to $2\pi i*Res_{(+bi)}$ because the integral over the circular arc is $0$.  So now I just need to calculate the residue at $+bi$. Can anyone give hints on how to do this?  I was thinking about multiplying by $(x-bi)^2$ and then evaluating at $bi$ but I'm not sure why this even makes sense.


If area is not uniform then how can current be constant? What happens to current density, electric field, drift speed? Are they constant?

let us assume that we have a conductor with a specified resistance ( case 1 ) and a normal conductor ( case 2 ) as shown in the figure , and now we apply an external electric field with a battery on it, we know that current density will be different in both the parts ,however , both the parts of the wire have different  resistances as there is a change in its cross section area but the potential difference will be equal as the length of both the parts is equal so is it correct to say that current running through both the parts is equal ?answer for both the cases


Black holes eventually decay by emitting radiation. It can take a long time. But from an outsider's perspective.   How long does it take from the perspective of someone falling into it?   I understand that time passes faster for someone closer to it, so would the rate at which it decays also appear to speed up?  Could it be so fast that the person falling into it sees it decay before it even reaches the surface?

I am not a professional physicist, so I may say something rubbish in here, but this question has always popped in my mind every time I read or hear anyone speak of particles hitting singularities and "weird things happen".   Now to the question at hand, please follow my slow reasoning... As far as I've learned, to reach a black hole singularity, you must first cross an event horizon. The event horizon has this particular property of putting the external universe on an infinite speed to the falling observer. Now due to the Hawking radiation, and knowing that the cosmic background radiation is slowly dimming, sooner or later every black hole in this particular instance of inflation we are living in will evaporate, according to an external observer of said black holes.  This means that every black hole has a finite timespan, as long as this universe survives that long. Now if we go back to the falling observer, we had already established that such an observer would see the outside universe "speed up" infinitely. This means that when the falling observer "hits" the event horizon, he will (or it if we speak about particles, which is clearer in this case), be immediately transported in time towards the final evaporation moment of the black hole. Either this or the particle gets some weird treatment. My point is, such a particle never gets to the singularity, because it has no time to get to it. The moment it crosses the event horizon, the black hole itself evaporates.  Where am I wrong here?


How can I split the ending of a file, like for instance I want file01 instead of file01.xlsx  My written code:  var filename = $v('P40_UPLOAD').split('\\').pop().split('/').pop();  var s = $s("P40_NAME",filename);   s.split('.')[0];  Unfortunately it doens't work.

Is there a way that I can get the last value (based on the '\' symbol) from a full path?  Example:  C:\Documents and Settings\img\recycled log.jpg  With this case, I just want to get recycled log.jpg from the full path in JavaScript.


In the __init__.py:  def tp(msg,o=None):   import datetime   omsg = ": %s" %repr(o) if o is not None else ""   dtf = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')   print(f"[{dtf}] {msg}{omsg}")   In a .py file  in the same directory (/package ?) :    Traceback (most recent call last):   File "/git/bluej/python/pointr/bluej/fusion/json_generators.py", line 243, in <module>     tp('Running human-in-loop tests ..') NameError: name 'tp' is not defined   What is the point of having __init__.py if the contents are not even visible to the files in the same package?  RE: the linked question and answers. It/they do not actually address my question here.  Update  I learnt how to run the script as a module within pycharm and that mostly  took care of the issue.  The tp() runs now: but it is still required to do     from . import tp

What is __init__.py for in a Python source directory?


I'm on 32 bit Lubuntu 16.04 and Chromium has the usual Flash version 11.2.9. A bunch of things won't play correctly so I've been trying to find a way to install Pepper Flash for a while and I'm not sure how to proceed.   I have the canonical repo enabled and I've tried installing PPAs in multiple ways--the package is always missing or there's no release file. Almost every online thread about this is from 2014 and I'm very new to Linux and very confused. And now the terminal is also on a loop when I use sudo apt-get update--it keeps trying to update & install ppa:skunk/pepper-flash which has no release file.  I have the latest tarball from Adobe. Could I extract it and manually install the Pepper Flash plugin as root? If so how would I do this? (I found a guide for this for Firefox but it didn't work out because it was majorly outdated.)  Forgive me if I'm missing something obvious, I have a headache. Thanks a bunch for any input.  EDIT: This got flagged as a duplicate but it's not--I was asking how to/if I could install via a tarball as root while the other question did not specify that this method was exactly what they needed info about. It is similar but not a duplicate.

I have Chromium web browser on my Lubuntu 13.04 (pre-installed).  I use LX Terminal (pre-installed) to write commands. I am trying to download flash player on Chromium using instructions on this :  sudo add-apt-repository ppa:skunk/pepper-flash   After typing in my password, this worked. Now   sudo apt-get update   I didn't need to type in my password, as I continued on the same terminal, but got W:/ and E:/ fetch file errors  sudo apt-get install pepflashplugin-installer   I continued on the same terminal despite the fetch file errors... and they said pepflashplugin-installer could not be found.  Is the last error because of fetch file errors, or because I need to download pepflash-plugin-installer somewhere? Or is it because of something else?  I cannot download the Chrome browser, and not looking to use flash player on my Firefox web browser (installed using lubuntu software center).


There exist any kind formula for the next sum? $$ \sum_{i = 0}^n \binom{n}{i}i^\alpha $$ with $\alpha$ an integer.

Is there any way to find:  $$\sum_{i=0}^n {\binom{n}{i}i^k}$$  I know that we can find it for small k by using binomial theorem by differentiating both sides and then multiplying both sides by x and repeating till the form presents itself and then putting x =1, but is there a way for any general power( k here) of i?


I came across a pretty clever little function that takes two functions, applies one on top of each other given an argument x:  def compose(f,g):     return lambda *x: f(g(*x))   Now my issue is with *x, as I don't see it really doing anything here. Why couldn't it be simple x (without the asterisk)?  Here are my tests:  >>> def compose(f,g): ...   return lambda *x: f(g(*x)) ...  >>> this = lambda i: i+1 >>> that = lambda b: b+1 >>> compose(this,that)(2) 4  >>> def compose(f,g): ...   return lambda x: f(g(x)) ...  >>> compose(this,that)(2) 4  >>> def compose(f,g): ...   return lambda *x: f(g(*x)) ...  >>> compose(this,that)(2,2) TypeError: <lambda>() takes exactly 1 argument (2 given)

In the following method definitions, what does the * and ** do for param2?  def foo(param1, *param2): def bar(param1, **param2):


Which one is correct?:  I was at the cinema yesterday. / I was in the cinema yesterday.  I was at a concert yesterday. / I was in a concert yesterday.  I was at the theatre yesterday. / I was in the theatre yesterday.  Why is sometimes "at" correct in different contexts and "in" in others? Can "at" mean "near" and "in"? If so, how could you guess that the speaker when he uses "at" means "in" or "near"? I know that "in" means inside (correct me if I'm wrong) but it's very confusing when it's "at" but not "in". I don't know if the speakers means inside or near. How is it possible to guess?  Is "at" more preferable in sentences like: "I was....". Is it some kind of a safer way not to make a mistake when you are tempted to use "in"? How do Americans and Britons see this?

I am really confused.  Which preposition is correct?     She is in/at the park.   They are in/at the park.   I am in/at the park.   Should I use in or at in these sentences?


When matter is converted to energy by means of $E=mc^2$, it produces quite a lot of "energy".  What I am having trouble understanding is exactly how the matter is transformed to energy at the atomic level. Do the atoms gain something or lose something in their internal structure? Do they just vibrate at different frequencies when the conversion occurs? Edit: This is a duplicate of the question, pardon me. Sorry.

I know that there's a difference between relativistic and rest mass. Relativistic mass is "acquired" when an object is moving at speeds comparable to the speed of light. Rest mass is the inherent mass that something has regardless of the speed its moving at.  When fusion happens, a certain percentage of the rest mass of two hydrogen atoms is converted into energy. I understand that $E = m_{rest}c^2$.   How does the rest mass of an object turn into energy? Does this involve particle physics? Doesn't this suggest that rest mass can be viewed as some sort of potential energy? It seems to me that it's a sort of locked energy that has to undergo a certain process to expel its energy to surrounding particles.  Also, Why does only a small percentage of rest mass turn into energy? Why not all of it. What dictates how much rest mass gets converted into energy?


Why can't we visualize Higher dimensions greater than 3? Is it just because the dimensions doesn't exist (Certainly I know that space-time is four dimensional) or any other physical reasons.

We consciously know and feel the first three dimensions and with some thinking time as well. But according to literature like String theory etc., we have many many more dimensions. We can readily express them in paper. But why can't we realize them? Why can't we experience them like the first three dimensions?  PS. I was pondering on this when I saw the movie Interstellar where even the fourth dimension 'time' is expressed using the first three dimensions for Cooper. PPS. The first three dimesnions being the X, Y and Z axes.


I'm having trouble deriving the PDF for the following problem (from the book Doing Bayesian analysis with R and BUGS):     Consider a spinner of the kind often found with board games, but with   a log10 scale from 1 to 100 (covering 0 to 360 deg). The spinner is fair, so any value is equally likely. What is the pdf at point $x$?   I know that the $x$ value at angle $t$ is given by  $$x = 100^\text{t/360}$$  Doing some transformation  $$x = \exp^{(t/360) \times \log(100)}$$  $$pdf(x) = pm(x)/dx$$  I also know  $$dt/dx = 360/(\log100 \times x)$$  Question     How to derive the answer below, using the information above?   Book answer     $$pdf(x) = 1/(2 \times ln(10) \times x)$$   Thanks.

Suppose $X$ is a random variable with pdf $f_X(x)$. Then the random variable $Y=X^2$ has the pdf   $$f_Y(y)=\begin{cases}\frac{1}{2\sqrt{y}}\left(f_X(\sqrt{y})+f_X(-\sqrt{y})\right) & y \ge 0 \\ 0 & y \lt 0\end{cases}$$   I understand the calculus behind this. But I'm trying to think of a way to explain it to someone who doesn't know calculus. In particular, I'm trying to explain why the factor $\frac{1}{\sqrt{y}}$ appears out front. I'll take a stab at it:  Suppose $X$ has a Gaussian distribution. Almost all the weight of its pdf is between the values, say, $-3$ and $3.$ But that maps to 0 to 9 for $Y$. So, the heavy weight in the pdf for $X$ has been extended across a wider range of values in the transformation to $Y$. Thus, for $f_Y(y)$ to be a true pdf the extra heavy weight must be downweighted by the multiplicative factor $\frac{1}{\sqrt{y}}$  How does that sound?  If anyone can provide a better explanation of their own or link to one in a document or textbook I'd greatly appreciate it. I find this variable transformation example in several intro mathematical probability/stats books. But I never find an intuitive explanation with it :(


I started GTA 5, now the task "GTAVLauncher.exe" tries to download 1 GB update from the internet, but it takes the whole bandwith.  Is there a way to limit the download speed of this task? I already tried , this worked fine, but unfortunattely it was only a test version and i can't efford it.  So is there a free method to limit the download speed of a task?

Is there a technique in Windows that can selectively limit bandwidth of a running process?


I do a two sample comparison with alpha = 0.05. The p-value I get is 0.33. I know that we do not reject the null hypothesis because it greater than 0.05. My question is can I interpret that the 0.33 is the probability that my null hypothesis is true. Could I also say that the null hypothesis probability of being false is 0.67?

After taking a statistics course and then trying to help fellow students, I noticed one subject that inspires much head-desk banging is interpreting the results of statistical hypothesis tests.  It seems that students easily learn how to perform the calculations required by a given test but get hung up on interpreting the results.  Many computerized tools report test results in terms of "p values" or "t values".  How would you explain the following points to college students taking their first course in statistics:   What does a "p-value" mean in relation to the hypothesis being tested?  Are there cases when one should be looking for a high p-value or a low p-value? What is the relationship between a p-value and a t-value?


The proposed duplicate is symbol plus label.  This is button versus symbol which is similar. I was hoping for advice on how to get users to realize the symbols are clickable. Putting a label next to the symbol is not going to help the user realize it is clickable.  The question is not how to get them to recognize the symbol but to realize they are clickable. In WPF users are used to clicking buttons (not text or symbols)   This is for a document management application This is a thick client (WPF) not a browser application But it will have a sister browser application In demo we get comments the screen looks busy The button line and image / icon lines are two options (will go with only one of those options) Search, browse history back, browse history forward, snapshot I like the image / icon Will users figure out they are clickable? What can I do to help the user figure out they are clickable?      This is the top left of here. There are 6 click symbol/icon. What make a user know the symbols are clickable?    Sorry if I wrote poor question but duplicates and answers are not addressing my question. What can I do to help the user figure out the symbols clickable? This may be a better perspective.  There a 6 clickable symbols on this page. How do I get users to recognize the symbols are clickable (even if they don't know what it means)?  From the aswer from Devin I am trying to represent the context of navigation bar. This is were I am currently:  I am not UX trained but I don't like the label. I think it is too much noise/clutter. It makes identification harder. It is not sexy.  They can learn the function of a button in a mouse over and will quickly memorize.

Are there any rules on when to use icons vs. icons with text vs. just text links in a web application?  For example:    vs.   save  vs.  save    Extra question: Is  save -or- save  preferable?


I want to use windows xp and ubuntu lts on same pc. How can I do it? and is ubuntu free os or we have to purchase it for proffesional or for best use?

I need my pre-installed version of Windows 7 (or any other version of Windows), how could I install Ubuntu without erasing it?


I am studying mathematical induction and most of the times I have to prove something. Like, for example:  $1 + 4 + 9 + ...+ n^2 = \frac{n(n+1)(2n+1)}{6}$  This time I found a question that ask me to find a formula for   $1 + 16 + 81 + .... + n^4$  How can I do this with induction? And is there really a formula for this sum?

As far as every question I've seen concerning "what is $\sum_{k=1}^nk^p$" is always answered with "Faulhaber's formula" and that is just about the only answer.  In an attempt to make more interesting answers, I ask that this question concern the problem of "Methods to compute $\sum_{k=1}^nk^p$ without Faulhaber's formula for fixed $p\in\mathbb N$".  I've even checked this  without finding what I want.  Rule #1: Any method to compute the sum in question for arbitrary $p$ is good, either recursively or in some manner that is not in itself a closed form solution.  Even algorithms will suffice.  Rule #2: I don't want answers confined to "only some values of $p$".  (A good challenge I have on the side is a generalized geometric proof, as that I have not yet seen)  Exception: If your answer does not generalize to arbitrary $p$, but it still generalizes to an infinite amount of special $p$'s, that is acceptable.  Preferably, the method is to be easily applied, unique, and interesting.  To start us off, I have given my answer below and I hope you all enjoy.


how to remove the popup message from standby inactivity?  Because this message is more than annoying, it is still there when I wakes.  Using ubuntu 13.10 (upgrade from 13.04) with Unity    TRANSLATION :   POWER  Automatic Suspend  Computer will suspend very soon because inactivity  EDIT [7-01-2013] : I believe we have found a solution on the ubuntu-fr.org forum. All credits to return Bybeu who created a script that literally removes the popup message. When I speak, I have not tested the script but if an expert could there have a look and give us his opinion, it would be appreciated.  You can find the info of Bybeu here to post # 13  or via

I'm using ubuntu 13.10 as htpc. To save some power, i have set it to suspend after 30minutes of inactivity. Before entering suspended state, a popup appears to warn me that computer is about to get put to sleep. This is a little annoyance since it appears when i resume the pc later.   How can i disable this notification for good?


I see an alignment issue with the Markdown Editing Help icon and its relevant help properties in the Firefox browser.  Firefox version: 43.0.2  But the same is properly aligned in Chrome and IE 10.  Screenshot for your reference:        After clicked the icon the help properties are not aligned properly.

Just posted a bug report, and found another one :p    (lame hand-drawn cursor coz windows doesn't capture the real cursor)  Oh yeah, I'm on Firefox.


I checked this code, and i saw that by the end of the function func()  the destructor of base class have been called twice. I dont understand why?? thank you..  class base  { public:     base(){cout << "ctor of base\n";}     ~base(){cout << "d-ctor of base\n";} }; class derived: public base  { public:     derived(){cout << "ctor of derived\n";}     ~derived(){cout << "d-ctor of derived\n";} }; void func(base ob) {     cout << "inside func\n"; } void main() {     derived ob;      func(ob);      system("pause"); }

Someone mentioned it in the IRC as the slicing problem.


I need to create a persistent file and save about 50mb of data in it.  . Is there another way to create local files that works in latest versions of Firefox and IE?

Is there local file manipulation that's been done with JavaScript? I'm looking for a solution that can be accomplished with no install footprint like requiring .  Specifically, I'd like to read the contents from a file and write those contents to another file. At this point I'm not worried about gaining permissions and am just assuming I already have full permissions to these files.


I have recently installed Ubuntu for the first time and it is running exceptionally slow.  Version:  No LSB modules are available. Distributor ID: Ubuntu Description:    Ubuntu 16.04.3 LTS Release:    16.04 Codename:   xenial   Processes:  top - 14:33:41 up  1:12,  1 user,  load average: 1.16, 1.63, 1.59 Tasks: 174 total,   1 running, 173 sleeping,   0 stopped,   0 zombie %Cpu(s):  9.6 us,  0.7 sy,  0.0 ni, 88.4 id,  1.3 wa,  0.0 hi,  0.0 si,  0.0 st KiB Mem : 11753128 total,  8966964 free,  1897648 used,   888516 buff/cache KiB Swap: 12024828 total, 12024828 free,        0 used.  9507028 avail Mem     PID USER      PR  NI    VIRT    RES    SHR S %CPU %MEM     TIME+ COMMAND         890 root      20   0  581064 176596  57956 S  6.3  1.5  23:49.16 Xorg           2297 ollie     20   0 2082488 240708 103988 S  2.3  2.0   1:23.95 Web Content    1682 ollie     20   0 1405520 341920  76848 S  1.7  2.9  12:16.67 compiz         1980 ollie     20   0 2391632 364112 145216 S  0.3  3.1   3:39.87 firefox        2055 ollie     20   0 2109904 202328 100968 S  0.3  1.7   2:00.45 Web Content    2759 root      20   0       0      0      0 S  0.3  0.0   0:00.04 kworker/u2:0   2828 ollie     20   0 1947012 242732 125488 S  0.3  2.1   0:40.05 Web Content       1 root      20   0  119988   6056   3900 S  0.0  0.1   0:01.19 systemd           2 root      20   0       0      0      0 S  0.0  0.0   0:00.00 kthreadd    My graphics controller:  VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Carrizo [1002:9874] (rev c5) (prog-if 00 [VGA controller])   For which I have installed graphics drivers using sudo apt-get install amd64-microcore. My laptop specs do not warrant the slow behaviour, which is AMD Quad-Core A10-8700P APU with Radeon™ R6 Graphics (1.8 GHz, up to 3.2 GHz, 2 MB cache) and 12 GB RAM.  Does anyone have any idea why it may be running so slowly?  Edit:  Using lspci -nnk | grep -A4 VGA returns the following:  VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Carrizo [1002:9874] (rev c5)     DeviceName: ATI EG BROADWAY     Subsystem: Hewlett-Packard Company Carrizo [103c:80ba]     Kernel modules: amdgpu 00:01.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Kabini HDMI/DP Audio [1002:9840]

The new open source AMDGPU driver pre-installed in Ubuntu 16.04 should support all the "Volcanic Islands" cards out-of-the-box. This means that AMD Radeon R9 285, R9 380/380X and R9 Fury/FuryX graphics cards will be supported out-of-the-box if Ubuntu 16.04 LTS is installed.  However I read that the open source AMDGPU driver has an experimental support for the "Sea Islands" graphics cards (HD7790, R7 260, R9 290, R7 360, R9 390). Is this support enabled by default on Ubuntu 16.04, or will these graphics cards use the Radeon driver?  Thanks


Since opinion based questions are not allowed neither here nor on stackoverflow, I would like to ask if any of you, know some other web page (outside Stack* ecosystem), where we can ask questions like:  "Which Java Web framework would you recommend to learn"   or any other, which by nature are opinion based.  EDIT1:  Allow me to explain a bit more - I know there are webgroups, forums and mailing lists BUT most of those are for single programming language or framework and I'm looking for something more generic. Stackoverflow is great because there are experts from all sort of programming languages and frameworks, so if it would be allowed to ask:   "Best web frameworks similar to ASP.NET MVC4"  I would get a lot of opinions, from different languages and frameworks, and that exactly what I'm looking for.

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


I'm trying to set a distance which is relative to the font size.  The problem is that the distance is reused several times in the document, potentially in environments with a different font size.  In each case the distance should automatically rescale to retain it's proportion to the font size.  Unfortunately, simply specifying the distance in em or ex doesn't work because the distance is stored at the size of em or ex in the current font.  When the font changes, the distance is not updated accordingly.  Is there a way around this?  Ideally the solution should work under both LaTeX and PlainTeX.  Below is a M(n)WE which shows the current, undesired, behavior.  \documentclass[12pt]{article}  \newskip\test \test = 1em  \begin{document}  In each row, the lines should be the same length.  \rule{0.4pt}{1em} \rule{0.4pt}{\test}  {\tiny\rule{0.4pt}{1em} \rule{0.4pt}{\test}}  {\Huge\rule{0.4pt}{1em} \rule{0.4pt}{\test}}  \end{document}

I noticed a behavior regarding lengths under fonstsize changes, which I'm hoping there is a way to circumvent.  Consider this MWE:  \documentclass{article} \begin{document}  \newlength\mylength \mylength=\baselineskip \def\stringmylength{\the\baselineskip}  mylength~~~  baselineskip~~~ stringmylength\\  \the\mylength~~~~~~~~\the\baselineskip~~~~~~~~~~~~~\stringmylength\\  \Large \the\mylength~~~\the\baselineskip~~~~~~~\stringmylength\\  \end{document}   with this output:    When I define a length in a scalable unit (here, as \baselineskip, though the same behavior occurs if I define \mylength as 2.7871ex), I would hope that, upon changing the fontsize, it would scale.  But \mylength does not.  I seem to recall reading somewhere that lengths are converted to some internal LaTeX unit, which would explain, perhaps, why a length, once specified, doesn't scale with fontsize.  Yet, it is clear that certain lengths do scale, such as \baselineskip, as given in my example.  Also, I could "work around" the problem by storing the length not as a length, but as a string (\stringmylength in my example), though that seems crass to me.    Is there a way to define a LaTeX length which will scale with fontsize changes?  If not, what is the prescribed way of manually modifying lengths to conform to fontsize changes?  [EDIT: As mentioned in a comment to David, and picked up on by egreg, this question concerns the formulation of lengths in the stackengine package]


I read  in which the following assertion was made:     The sun, in fact, emits light in all colors, but since yellow is the   brightest wavelength from the sun, that is the color we see with our   naked eye   Now, as a photographer, I was always taught that the light from the sun was brightest in GREEN and that is why green is the color to which our eyes are most sensitive. In fact, if we look at the spectrum of the sun:    As we can see from this graph, the most intense light from the sun is not yellow, it is green. So, is NASA just wrong or what? Why does the sun appear yellow?

The spectrum of the Sun as seen at sea level can be seen at  so we can see that wavelengths around green to yellow are the ones that are the most present. The human eye seems to be more sensitive to green wavelengths (around 555 nm which is plain green) compared to others: see .  However the Sun appears mostly white/yellowish.  I don't understand why. The human eye sensitivity for orange/yellow/blue is lesser than for green. Much lesser in case of red wavelength. So even though the spectrum is a continum of all these wavelengths why is the eye fooled toward white?  And why more toward yellow than green?  Thanks.


How do you I create a new user account on Ubuntu?

Just switched from 10.04 to 11.10. I'm wondering about the limited options in the GUI for managing users and groups. Where is the old GUI to change groups, id's, etc. I know that I can do this from cli, that's no problem. But I want this comfortable GUI back.


The Stack Exchange Android app crashes when I tap on a job in recommended jobs.  I also did a data reset for the app and reinstalled it but that didn't fix the issue.   Attaching screenshot of the section.   Also, all other sections are working fine as expected except the Recommended Jobs, which causes sudden app crash.   App Version: 1.0.89 Device Manufacturer: OnePlus Device Model: ONEPLUS A3003 (OnePlus 3)  OS Version: 6.0.1 (26)   Edit:  Added the  of the issue.

Clicking any Careers (or Jobs) ad in the Android app feed results in an instant crash for the Android App version 1.0.89.


I have given the wrong permission to the /etc folder  chmod -R 777 /etc   When I want to login as root it gives me an error and the following output.   How can I correct the permissions?  system13@motpl:~$ sudo su sudo: /etc/sudoers is mode 0777, should be 0440 sudo: no valid sudoers sources found, quitting sudo: unable to initialize policy plugin system13@motpl:~$ su root Password:  su: Authentication failure system13@motpl:~$

I was trying to run chmod -R 777 ./ but ended up typing chmod -R 777 / and set 777 on my entire machine. What can go wrong? How can I fix it?


I wonder if there is the same difference between identity === and equality == operators in angular directives like in pure javascript?  For example is  ng-if="value === 'foo'  better than  ng-if="value == 'foo'  What I checked is that   ng-if="true == 1  passes but   ng-if="true === 1  doesn't, so it looks like it works the same way like pure js. On the other hand in angular source they use just equality check, even tho in js identity is preferred.    Which operator should we use in angular directives?  EDIT: To clarify - I'm not asking about javascript conditions, this has been already answered on stack, my question is - is there any difference in conditions between pure js and angular directive conditions?

I'm using  to go through JavaScript, and it's returning many suggestions to replace == (two equals signs) with === (three equals signs) when doing things like comparing idSele_UNVEHtype.value.length == 0 inside of an if statement.  Is there a performance benefit to replacing == with ===?   Any performance improvement would be welcomed as many comparison operators exist.  If no type conversion takes place, would there be a performance gain over ==?


In C# there are String objects and string objects.   What is the difference between the two?  What are the best practices regarding which to use?

Example (note the case):  string s = "Hello world!"; String s = "Hello world!";   What are the guidelines for the use of each? And what are the differences?


I have Internet access to my laptop, over Wi-Fi. I have connected a device with an Ethernet port (with an Ethernet cable from my laptop to the device), and set up a local area network between the two, so that they can ping each other. Now I want the device to access the Internet, i.e., to forward "Internet" from Wi-Fi on my laptop to the Ethernet port of the laptop.  How do I set this up if the laptop runs Ubuntu?

I have a Linux (Ubuntu 12.04) PC connected to the internet with a Greenpacket WiMax USB modem. I want to share the Internet connection with another computer running Windows 7 Home Premium, connected to the Linux PC over a LAN. Is this possible? How? Is the reverse possible instead (connecting the internet to the Windows computer and sharing it with Linux)?


When I installed Ubuntu 18.04 I didn't keep a partition with Windows, now I want to create a Windows partition. Can it be done?

About two weeks ago I had a problem with my PC that my brother wrote a question about at .  I still haven't solved the problem, so my PC is unusable now.  Now I think that it would be simpler to re-install both Win7 & Ubuntu than repair them, but there're some data on their partitions. I want to recover this data.  These partitions are not mountable for some reason. I don't know why.  sudo fdisk -l about the problematic partitions:     Device    Boot      Start         End      Blocks   Id  System /dev/sda1            2048     147912703    73955328   83 Linux /dev/sdb2            206848   174079999    86936576    7  HPFS/NTFS/exFAT   And in GParted:      And the error of the mount command:  Failed to mount '/dev/sdb2': Invalid argument The device '/dev/sdb2' doesn't seem to have a valid NTFS. Maybe the wrong device is used? Or the whole disk instead of a partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?   And the exact same message for /dev/sda1  How can I recover my data from those HDDs?  EDIT     I have tried to specify the type of the drive:  $ sudo mount -t ext4 /dev/sda1 /olddisk mount: wrong fs type, bad option, bad superblock on /dev/sda1,        missing codepage or helper program, or other error        In some cases useful info is found in syslog - try        dmesg | tail  or so $ sudo mount -t ntfs /dev/sdb2 /olddisk NTFS signature is missing. Failed to mount '/dev/sdb2': Invalid argument The device '/dev/sdb2' doesn't seem to have a valid NTFS. Maybe the wrong device is used? Or the whole disk instead of a partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?   EDIT     sudo ntfsfix /dev/sdb2 returns:  Mounting volume... NTFS signature is missing. FAILED Attempting to correct errors... NTFS signature is missing. FAILED Failed to startup volume: Invalid argument NTFS signature is missing. Trying the alternate boot sector Unrecoverable error Volume is corrupt. You should run chkdsk.


I'm trying to create a similar effect to . And I found a nice tutorial with something . However, I wasn't able to add a text there. So it looks like the  is not using any volumetrics at all? Can you help to decipher this shader?

I'm trying to recreate the windows 10 background effect on a logo I've made in blender.  Half the logo has a glass like material, the other half has a steel like material. And I'm using cycles at the moment.  I've put various light sources behind the logo and tried a few variations of volumetric scatter in the world to get the god ray sort of feel coming off the logo, but it's just not looking anywhere near as effective as I'd like.  I know the win10 background was a real set and photographed, but has anyone come across a tutorial to do something similar in blender?  I'm very new to the tool, I'd appreciate any pointers in the right direction.


In the lyrics of First of May, there is a line "But guess we'll cry come first of May". What is the meaning of it? Especially, what is the meaning of "come first of May"? What will "come first of May"?   Thanks

I’ve stumbled upon the following sentence reading a blogpost:     Come C++11 (programming language) there are some extra options for our ownership policies.   What does come mean here? It doesn’t look analogous to any clause I’m aware of.  (Well, I understand the general meaning of the sentence but I don’t understand how come in such a syntactic form fits in here. If anything (maybe the blog author was incorrect?), the sentence means that after C++11 has come there are those options.)


I am able to compile and run this. How it is possible to write a try-catch block outside the main scope, seems to defy my logic? Any term to describe this behavior?  int main() try {  }  catch(...){}

Note that this function does not have a "{" and "}" body.  Just a try/catch block:  void func( void ) try {     ... } catch(...) {     ... }   Is this intentionally part of C++, or is this a g++ extension?  Is there any purpose to this other than bypass 1 level of {}?  I'd never heard of this until I ran into


If $G$ be a group and $H\le G,$ $K\le G$ such that $\mid G:H \mid=m$ and $\mid G:K \mid=n$ then  we know the following two relsults from group theory.  $(1)$ $lcm(m,n) \le \mid G:H\cap K \mid \le mn$   $(2)$ $\mid G:H \cap K \mid \le mn.$ The equality of $(2)$ holds iff $G=HK.$   I know the proof of these two results. Note that $gcd(m,n)=1 \Rightarrow \mid G:H \cap K \mid =mn(by (1)) \Rightarrow G=HK(by (2)).$ But I want to prove $gcd(m,n)=1 \Rightarrow G=HK$ without using $(2)$. Any hint is accepted.  I have seen the solutions to similar question.But it's assuming that $G$ is finite.But what happen if $G$ is infinite

I'm struggling to proof that if $H$ and $K$ are subgroups of  finite index of a group $G$ such that $[G:H]$ and $[G:K]$ are relatively prime, then $G=HK$. I don't know why I can't answer it, because this question seems easy. I'm stuck maybe because I've studied so far just Lagrange's theorem and some of its consequences. But I think we don't need much more, because this is the material covered so far by the Hungerford's book.  I need help.  Thanks.


So I live in a rented apartment and some things did not go as planned and ended up with a puppy before moving instead of after. Anyways I just noticed he has been chewing on the frame inside my bedroom and I'm just wondering how to fix this so I can obtain as much of my deposit as possible

My dog chewed the bottom part of the doorframe to my bedroom.  I live in a rented apartment, so this is not OK.  Is there any way to fix it and make it look somewhat presentable (doesn't have to be perfect)?  How do I find a matching frame?  How do I match the paint?    Update: Just wanted to thank everyone for their help!  @XOPJ: Thanks, that is useful to know.  Actually, I don't think she actually chewed it, but simply scratched at it when I left her in the room for a while (she's got separation anxiety).  So my description was not quite accurate to begin with!  Regarding replacing the trim, I think that's just too much work for someone like me who doesn't know much about DIY projects.  I considered this initially before coming to this forum, but there doesn't seem to be an easy way to remove the trim, and I'm afraid I'd knock a huge chunk out that I'm not supposed to if I tried to pry it off!  My filler experiment has been a half-success:  I had one big chunk which I managed to glue back in place, and I filled in the rest with wood filler and painted over it.  Since it's near the bottom of the door, you don't notice it unless you're looking for it.  However, I think I'll try to touch it up at some point in the future.


I'm writing a shell script that has to know if a certain program version is less or equal to version x.xx.xx here is an example script to try and explain what I want to do: #!/bin/bash  APPVER="`some command to output version | grep x.xx*`"  if [[ "$APPVER" is smaller or equal to "x.xx*" ]]; then     do something else     do something else fi  is there a way to do that? I found ways to compare numbers, but they won't work with version numbers. I need a solution that uses no or as little as possible programs. any help is appreciated!

Suppose I want to compare gcc version to see whether the system has the minimum version installed or not.  To check the gcc version, I executed the following  gcc --version | head -n1 | cut -d" " -f4   The output was  4.8.5   So, I wrote a simple if statement to check this version against some other value  if [ "$(gcc --version | head -n1 | cut -d" " -f4)" -lt 5.0.0 ]; then     echo "Less than 5.0.0" else     echo "Greater than 5.0.0" fi   But it throws an error:  [: integer expression expected: 4.8.5   I understood my mistake that I was using strings to compare and the -lt requires integer. So, is there any other way to compare the versions?


I want to install the ubuntu 12.04.2 in my computer, which already has windows 8. I have no idea how to do it, I cannot understand a single word of the other post since I'm new in all this. Can somebody help me using easy lenguage (and pictures if possible), please?

I'm absolutely new to Linux. I would like to know how to install Ubuntu alongside the pre-installed Windows 8+ OS.  Should I do it with Wubi, or through the Live USB/DVD?  What steps do I need to take to correctly install Ubuntu?


I'm trying to debug some \newcommand macros I'm working on, and I've got it down to this minimal example. All it does is define two lengths and then set their values - it doesn't use them for anything.  \documentclass{article}  \newlength{\xscale} \newlength{\yscale}  \newcommand{\setscale}[2] {     \setlength{\xscale}{#1}     \setlength{\yscale}{#2} }  \newcommand{\mystyle} {     \setscale{0.25cm}{0.18cm} }  \begin{document}  foo, \mystyle% bar  foo, \setlength{\xscale}{0.25cm}\setlength{\yscale}{0.18cm}% bar  \end{document}   The output looks like this:    Why is that large space being inserted when I wrap the \setlength commands inside \newcommand, but not when I don't? How can I define these commands so that they will set the lengths without inserting extra space into the document?

I found two things peculiar in the common style of macro definitions:   Ending lines in macro definitions with '%'; Not wrapping a macro name in braces.   Example:  \newcommand\examplemacro{%     \somecommand%     \othercommand% }   Being a software engineer first and a LaTeX user a distant second, I would expect:  \newcommand{\examplemacro}{     \somecommand{}     \othercommand{} }   Is there a reason for doing it the former way, or is it merely a matter of habit?


There is a two-line spacing between comments. But if I upvote any comment, the spacing gets reduced to single-line spacing. Why is this?

Single-line comments show like two lines, simply to give space for the Vote and Flag icons, which are placed with above the other. Can these buttons be placed next to each other? This would allow single-line comments to look like single lines. Example:


file contains no newline terminator.  final line of file is mixed to the username in command prompt.  file:  line 1   test:  user /: cat file line 1user /:   Solution is suggested to be : to add a new line terminator to file.  How can this solution be regarded as the proper thing ?  this means in the future a strage file can ruin our mood if it does not have a new line terminator.  Logic would suggest.. to not trust anything. but to be correct yourself.  So If I want to be correct.. I should never permit my username to show up at the end of some string regardless of it has a new line terminator or not.  I am not suppose to count on them.  I am suppose to be my own entity.   is there an alternative solution to ensure my username never becomes a victim of a "new-line-terminator-less" file or string ?  Perhaps solutions can not exist because it would make other things disfunctional such as "tail" and etc ?  but there has to be some logic.   looking for some logic.

file contains just 1 line:  aaa   when I run "cat file" it mixes to username  user /dir : cat file aaauser /dir :   What could be the problem ?  Extra Info:  perhaps this is not properly set in bashrc ? ?  PS1='\u \W : '   UPDATE:  shouldnt there be a solution other than including a newline to the file ?  Why would there be no care for the elements that can distort the command line prompt ? ( by not having a new line )


I'm trying out the xenial nightly, and I'm wondering if I have to download a new nightly once in a while to keep up to date, or if running sudo apt-get dist-upgrade will keep me current.

I installed an Ubuntu alpha or beta and have been keeping it up to date.   So, Should I presume that my system has automatically updated to the next alpha or beta, and will be running the official release when it's finished?


The integral I'd like to solve with contour integration is $\int^{\infty }_{0}\dfrac {dx}{x^{4}+1}$ and I believe the simplest way to do it is using the residue theorem. I know the integrand has four simple poles at ${\dfrac {\pi}{4}}$,${\dfrac {3\pi}{4}}$, ${\dfrac {-\pi}{4}}$,${\dfrac {-3\pi}{4}}$ but I am stumped on how to calculate the residues at those poles. Since my contour is in the y>0 space I only need the poles at $\dfrac{\pi}{4}$ and $\dfrac{3\pi}{4}$  I know that the integrand $f(z)=\dfrac{p(z)}{q(z)}$ where $q(z_{0})=0$, $q'(z_{0})\neq0$, $p(z_{0})\neq0$ so the Residue of $f(z)$ at $z=z_{0}$ is $\dfrac {p(z_{0})}{q'(z_{0})}=\dfrac {1}{4z^3}$. How do I calculate the integral using the residue theorem?

I have to compute this integral $$\int_{0}^{\infty} \frac{dt}{1+t^4}$$ to solve a problem in a homework. I have tried in many ways, but I'm stuck. A search in the web reveals me that it can be do it by methods of complex analysis. But I have not taken this course yet. Thanks for any help.


Let $R,S$ be two rings with identity. Prove that every ideal of $R\times S$ is of the form $I \times J$ where $I$ is an ideal of $R$ and $J$ is an ideal of $S$ .  Obviously $I \times J$ is an ideal of $R\times S$. Conversely let us assume that $M$ is an ideal of $R\times S$.   To show $M=I\times J $. How to proceed?

I am trying to solve this problem:      Let $ R_1,...,R_n$ be rings with identity. Every ideal of $R=\prod_{i=1}^n R_i$ is of the form $\prod_{i=1}^n I_i$  where $ I_i$ is an ideal of $R_i$.    The first part is clearly if $J$ an ideal of $R$ then $J\subset \prod_{i=1}^n I_i$, but i can complete the rest..any help..


My PC was infected by belombrea. I was told to reinstall OS, but I did it a different way. Is this sufficient?  Go to the search bar, type reset, click reset this PC. It'll give 3 options. On the bottom there's more recovery options with "learn how to start fresh with a clean installation of Windows PC", is that the same as reinstalling the OS? If I try click, it'll tell me that I'll need to reinstall Dell Touchpad, Realtek Card Reader & Realtek High Definition Audio Driver from the web. How can I do that?

What should I do if my Windows computer seems to be infected with a virus or malware?  What are the symptoms of an infection? What should I do after noticing an infection? What can I do to get rid of it? how to prevent from infection by malware?   This question comes up frequently, and the suggested solutions are usually the same. This community wiki is an attempt to serve as the definitive, most comprehensive answer possible. Feel free to add your contributions via edits.


I just flagged an answer as 'not an answer' and it immediately appeared in the flag queue which in  from yesterday I believed to have been removed. When I go into my queue the flag does not show but it shows the flag on the right hand side but no where else. When I click on the link to the flag the page refreshes but nothing else happens.

The comment with the Flagged Posts that seems to be new as of today states there are posts with flags awaiting my attention but the counter shows zero and when I go into flagged posts there is nothing waiting for me.


This year I will submit about 16 aplications to different universities for graduate studies at the US. However, I found that there are new professors looking for Phd. students. So as a foregin student with only a bachelor of science in computer science, how should I approach to a professor looking for students?. My background is the following:   CS major at the first university of my country A research thesis  3 research papers in the field of the professor's interest. (not ground breaking, the first one is in a local congress the second is in an international conference indexed by springer's LNCS and IEEE, the third is also indexed in springer.) 3.0 GPA I will take the GRE and TOEFL the nexts weeks   After all, I read 2 papers of this professor an I would like to be his Phd. student. If he would like to know me I will take a trip to the USA just to talk with him. How can I email to this professor and let him know I am an international enthusiastic stundent that wants to extend his work.

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 saw the elephant at the zoo."  "I saw elephants at the zoo."    In sentence 1, is the word the elephant denote a proper noun and in sentence 2, is elephants denoting common noun?  Note: Please visit the link (Definite article section) -

I was reading a paragraph about lions and I came up with a question about the definite article (the).  Let me tell you first what I know about it.     1->We use the before a singular noun (when we are sure about the noun.    And the listener and the speaker both know about it).      2->We use the before a plural noun (again when we are sure about the noun,   and we are not talking generally).   So, my question is why does the writer use the here as we are not talking about any specific lion or lions. We are talking generally.  The Paragraph:     Living in the grasslands, scrub, and open woodlands of sub-Saharan   Africa, the lion is the second largest cat in the world. It is dwarfed   slightly by the tiger, which is closely related and has a very similar   body type.    Can we re-write the paragraph something like this:     Living in grasslands, scrub, and open woodlands of sub-Saharan Africa,   lions are the second largest cat in the world. They are dwarfed   slightly by tigers, they are closely related and has a very similar   body type.


When an object leaves a celestial body (e.g. planet or star) with it's escape velocity, according to first law of motion, it will continue travel away from the body with the same speed (without having need of any additional energy). Let's assume that: At time t1 the object has at distance d1 from the celestial body. And At time t2 the object has at distance d2 from the celestial body. Here t2 > t1 and d2 > d1 Now if the object falls from distance d1 back to the body, at the time of impact it will have certain energy. Let's assume this energy is j1 Jules. And if the object falls from distance d2 back to the body, at the time of impact it will have more energy than j1 (Because, d2 > d1 hence gravitational acceleration will cause more speed at the time of impact) Let's assume this energy is j2 Jules Question is: This total system didn't consume any external energy (neither the object was supplied with additional fuel after it starts its journey from celestial body). Then how does it generate more energy just by travelling for more time in space? How can this be explained in the context of law of conservation of energy? Update 1: This is not question about escape velocity. It's more about how to explain relation of energy of impact of a trajectory (if it falls back) with the amount of time it has travelled in space. More the amount it travels, more is it's impact. How to explain that especially wrt Energy conservation law. Update 2: I was using some online free fall calculators (for e.g. ,  and ) and they calculated speed exceeding escape velocity for height more than 10 thousand kilometer. That made me to think of this question.

I have several confusions regarding . I am sure I am missing something(s) obvious or maybe I am taught wrong.     Lets say we throw an object of any mass at exactly escape velocity of earth calculated from $v^2=\frac{2GM}{r}$ which is almost $11 \text{km s}^{-1} $ but I am talking about exact escape speed.   That ball initially has $KE=\frac{1}{2}mv^2$ and $PE=mgh$. Wikipedia says and I quote      In physics, escape velocity is the speed at which the kinetic energy plus the gravitational potential energy of an object is zero.     How is that possible? As $F=\frac{GmM}{r^2}$ no matter how much the particle travels away from earth's surface it will always be accelerated towards earth. With increasing $r$ the $F$ will decrease but it will never reach $0$. That means that there will be no point where the particle will stop and will continue to move with slower and slower speed will never reaches zero. Am I right? A request: Please explain exactly what happens to particle's $KE$ and $PE$ at different points such as at $r=0$ and at $r=\infty$.


The derivative of a polynomial is useful in algebra because of its algebraic properties. However, the definition itself originally comes from analysis. It seems like too big a coincidence that an analytic definition continues to be so useful even in contexts where the concepts of limits and (analytic) derivatives no longer make sense. Is there an explanation for this?  An example of how such an explanation could be provided is:   An "algebraic" definition of the derivative of a polynomial over a field $F$, for example as the unique polynomial satisfying some property, rather than just by providing the formula with no explanation. An explanation as to why this also happens to give the rate of change when $F=\mathbb R$. For example, maybe a proof that the rate of change equals the algebraic derivative, but which doesn't involve explicitly calculating the limit, it just shows that the rate of change must satisfy some property which characterizes the algebraic derivative.

When studying polynomials, I know it is useful to introduce the concept of a formal derivative. For example, over a field, a polynomial has no repeated roots iff it and its formal derivative are coprime. My question is, should we be surprised to see the formal derivative here?   Is there some way we can make sense of the appearance of the derivative (which to me is an analytic object) in algebra? I suspect it might have something to do with the fact that the derivative is linear and satisfies the product rule, which makes it a useful object to consider. It would also be interesting to hear an explanation which explains this in the context of algebraic geometry.  Thanks!


So I'm going through the edit motions, and am presented by . It wrecks the code spacing. It's a bogus edit.  Since it's not quite bad enough to be vandalism, I spend the time writing an explanation in the custom field. By the time I hit 'reject' the approval bots have waved it through.  Since some of us actually might care about the correctness of edits, should I be forced to correct this bogus approval by going back and editing the post back to the original spacing?  This is not the first time I've been rebuffed when rejecting a pretty bad edit. Surely this process needs to be 'flaggable' so we can identify those abusing or misusing their edit approval powers? The 'test' edits are too easy to spot and don't seem to a sufficient deterrent to number bumpers (people who do edits purely to bump numbers and earn badges).

Problem User submits a  which should be rejected (at least 3 reasons pop-up straight away...) You happen to come across this and you want to do the right thing, which is reject the suggested edit. So you hit Reject button and select your reason. Oops...  So then you refresh the page and click the more link to see the reviewers and stats  Right, I am not saying this is not entirely possible to come across 11/35/14 suggested edits which really improved the post... but how likely is this to happen?  UPDATE aimed at 's suggestion  which should be clear based on  Let Me Flag Currently, there isn't any way to actually flag these guys for moderators attention. I know I can go to their profiles/ activity tabs/ comments and leave a comment explaining how to act in the suggested edits queue... I can write a custom message under one of their comments and explain the problem to the mod...well, I am not going to do that.. These are painful ways of achieving something that should be exposed right there at the review stage. There needs to be another/simpler way to tell our mods and other already establish and trusted users that there are some potential robo-reviewers which need handling (possibly a ban1)  The mechanics A suggested review flag [SRV] flag's meta could be as follows (obviously just an idea)  Reviewer Link to the review Optional: reason for flagging Date/time Flagger  Each user would have a counter against his profile stored in the back end. How many times his action has been flagged, and how many times mods(10K+ possibly as well) have approved such a flag (robo-alert). This number would not be exposed to users, so nobody but the diamond mods know the raw numbers/count. If the system detects, let's say, 10 approved flags the reviewer gets an automatic ban(to be discussed). I think we could add those types of flags to the  and let those 10K+ help handle those types of flags. Any ideas are welcome as it's quite difficult for one person to invent and think throughout the entire system. Consequences Pros  slowly disposing of robo-reviewers  in a long run: improve the quality of suggested edits being approved  users awareness -> "my actions are somehow analyzed further"   could educate users a bit more of What do I approve/reject and consequences for being a robo-reviewer.   Cons  Increased load of moderation required  Implementation of such system (developer time, etc)   1 - I am not the one to judge when a ban is necessary. It would up to the mods when someone actually deserves a ban. It could also be dependent on the amount of approved flags a reviewer has received


$$\lim_{n\to \infty}2^{\frac{1}{n}}$$   Basically looking at $$\lim_{n\to \infty}2^{\frac{1}{n}}=2^{\lim_{n\to \infty}{\frac{1}{n}}}=2^0=1$$  But if I use $$\lim_{n\to \infty}2^{\frac{1}{n}}=\lim_{n\to \infty}e^{\ln\left(2^{\frac{1}{n}}\right)}=\lim_{n\to \infty}e^{{\frac{1}{n}}\cdot{\ln(2)}}=\lim_{n\to \infty}e^{\frac{1}{n}}\cdot\lim_{n\to \infty}e^{\ln(2)}=1\cdot2=2$$  Where did I got it wrong?

This was a practice problem I was given.      Show that $\lim_{n \rightarrow \infty} \sqrt[n]{a} =1$.   My argument is as follows: \begin{align} \lim_{n \rightarrow \infty} \sqrt[n]{a} &= \lim_{n \rightarrow \infty} e^{\ln(\sqrt[n]{a})} \\ &= e^{\lim_{n \rightarrow \infty}(\frac{1}{n}) \ln(a)} \\ &= e^{\lim_{n \rightarrow \infty}(0 \cdot \ln(a))} \\ &= e^0 \\ &= 1.\end{align}


One of the requirements of a sigma-algebra is that all countable unions are in the algebra i.e. if $A_n\in B$ for $n=0,1,2,...$ ($B$ been our algebra and $A_n\subset U$) then we require: $$ \bigcup\limits^\infty_{n=1} A_n\in B$$ my question is whether this includes all finite unions i.e. do we also require: $$A_1 \cup A_4\in B$$ etc?

I'm really struggling to grasp why $\sigma$-fields are not necessarily closed under finite union.  If the above statement is true then;  Let $(\Omega, \mathcal{F},P) $ be our probability space such that $(A,B \in \mathcal{F} \Rightarrow A \cup B \not\in \mathcal{F})$.  Surely $P(A \cup B) $ then cannot be evaluated.  Any advice on how I could move forward would be greatly appreciated.


You know how sometimes you want to cry, but do not cry.  Maybe a few tears are shed, but you mostly just choke up.  The urge to cry is there, perhaps overwhelmingly, but you suppress it somehow and don't actually cry.  Is there a word for this state?  I've always used "crying" but it really isn't quite crying yet.

You know when you see something touching and moving and you feel like tears are about to come out of your eyes, yet you're able to barely control it; how do you describe this feeling or state?  i.e. I was all [...] at the sight of his master curled up asleep in fetal position on the floor at the vet's beside his dog.  Take a look at this and you'll know what I'm talking about:


While trying to install a 14lb metal shelf to the wall, I had learned from a previous installation mishap to upgrade from plastic anchors to something stronger. I picked up a few toggle bots (3/16" w 3" bolts).   When I started drilling the 1/2" hole, I realized my bit wouldn't go much further than an inch in. It was a hard stop. After the 1" of drywall immediately behind it is what looks like concrete. There is NO space between the drywall and the concrete.  I live in a new condo and the wall happens to be one that I share with my neighbour. I'm not sure what material it's made of, or if these toggle bolts will work.  Does anyone have any advise on how I can get these heavy shelf installed, toggle or no toggle.

I have a predicament, I am putting up a shelf into the wall.  The wall is plaster, and then hollow and then concrete. I have screws with toggle bolts on them.  The 2 inch screw with the toggle bolt was too short to get the toggle bolt inside the plaster to the hollow part.  The 3 inch screw with the toggle bolt is too long because it hits the concrete. But the toggle bolt will reach into the hollow part.  How do I approach this dilemma? Do I need to drill into the concrete somehow? I think my current drillbit is incorrect for doing this, but I'm not sure.  Insight appreciated


I am wondering what are the affects to current in a parallel circuit and if the current can be run in parallel in the same way as with voltage (eg. To power 3 phones in Parallel would I need 3 times the current) Edit: I am using the phones simply as a example I am trying to power 10 laptops at 19.5 volts (running them in parallel) . And each laptop needs 8 amps to run  So my question is to power the 10 laptops  in parallel do I need 8 amps (the power necessary for one laptop) or 80 amps (The power necessary for 10 laptops).

Power supplies are available in a wide range of voltage and current ratings.  If I have a device that has specific voltage and current ratings, how do those relate to the power ratings I need to specify?  What if I don't know the device's specs, but am replacing a previous power supply with particular ratings?  Is it OK to go lower voltage, or should it always be higher?  What about current?  I don't want a 10 A supply to damage my 1 A device.


This is the simple program I am trying to run which shows error. If I pass URL without whitespace, then the program runs properly.  Error: 404 Bad Request.    If instead of "Hey You", I pass "Hey%20You". The program runs correctly.

I'd like to know do I normalize a URL in python.   For example, If I have a url string like : " goo/bar.html"  I need a library in python that will transform the extra space (or any other non normalized character) to a proper URL.


Are the parameters (the beta's) that result from a ridge regression interpretable as we normally do with canonical linear regression? Can I use them to test hypothesis? Or is ridge regression something that can be used only for Machine Learning (i.e. prediction) tasks?

I know about the benefits of regularization when building predictive models (bias vs. variance, preventing overfitting).  But, I'm wondering if it is a good idea to also do regularization (lasso, ridge, elastic net) when the main purpose of the regression model is inference on the coefficients (seeing which predictors are statistically significant).  I'd love to hear people's thoughts as well as links to any academic journals or non-academic articles addressing this.


const arr = new Array(1);  arr[0] = {x: "first", y: "second"} arr[0][5] = "third" console.log(arr) // Result: [{5: "third", x: "first", y: "second"}]  Why did it add 5: "third" in the beginning like that? How does JS handle this under the hood?

The primitive types (number, string, etc.) are passed by value, but objects are unknown, because they can be both passed-by-value (in case we consider that a variable holding an object is in fact a reference to the object) and passed-by-reference (when we consider that the variable to the object holds the object itself).  Although it doesn't really matter at the end, I want to know what is the correct way to present the arguments passing conventions. Is there an excerpt from JavaScript specification, which defines what should be the semantics regarding this?


I have a Minecraft Java Edition file that I would like to convert to use in Minecraft Bedrock Edition on Windows 10.  Is there any way to do this?

Now that I've discovered that I can host a , I'd like to know if is it possible to use the textures and maps of the PC version for the pocket version.  I'm planning to visit Peru and Machu Picchu. It would be really cool to entice them for the voyage by letting them play a  in their favourite video game. Unfortunately, this God of Deceit world looks really sophisticated. I don't believe the Pocket Edition would be able to play it.


I have 2 servers, A & B, both running CentOS 5.7.  If I ssh using Putty from Windows 7 to server A or B, the password prompt is quick  But if I ssh from Ubuntu 11.10 to server A, the password prompt takes a long time, almost 2 minutes; while server B password prompt is quick, though not as quick as using Putty.  htw@htw-HP-ProBook-4421s:~$ time ssh use@A.biz user@A.biz's password:  Connection closed by A.biz  real    2m33.170s  htw@htw-HP-ProBook-4421s:~$ time ssh user@B.biz user@B.biz's password:   real    0m1.904s   There shouldn't be anything wrong with both servers since ssh-ing from Win 7 is quick. The puzzling bit is logging onto server B is faster than onto server A using Ubuntu. Both servers sshd.conf are already set to UseDNS=no  How do I debug this?

I have an old laptop running as a server (It runs Ubuntu Natty).  When I SSH into the box, it often takes a long time to log on, if it's been a while since last time I logged on. I suspect the reason to be that the SSH daemon is put to sleep somehow, and has to be woken before I can log on. Can anyone explain why this happens?  Additional info  Besides SSHD the server runs Transmission Daemon and two Dropbox instances.  I have appended "UseDNS no" to /etc/ssh/sshd_config.  The machine is running a desktop kernel, because I use it as a backup desktop machine as well. Would it help to change it to a server kernel, or would that disable my desktop? I have read that there might be issues with nVidia drivers when running a server kernel, but don't know if this applies on Natty.


I've been reading some about the difference between Google Analytics "Avg Visit Duration" statistic and their "Avg Time on Page" statistic.  I've found many good answers, among them, this .  However, even as I read these explanations of the two numbers, I'm struggling to understand how it could be that my blog site has an Avg Time on Page that is far above the Avg. Visit Duration...  My Avg. Time on Page is currently   05:23   My Avg. Visit Duration is currently 01:58  Does that make any sense?  I thought that the average visit duration has to be larger than the average time on page, because it's a super-set of that.  I thought it's the difference in time between the first and final pageviews of a visitor, which would always be larger than the view time of a single page... What am I misunderstanding?  Thanks!

I have the following Custom Report set up in Google Analytics:  Metrics:   Avg Time on Page Avg Time on Site   Dimensions:   Page   So a report looks like this:  Page                    Avg Time on Page         Avg Time on Site /an-article             00:03:14                 00:00:11 /another-article        00:05:11                 00:01:07 /something-written      00:03:00                 00:00:31   Why is it that for each 'page', the 'site views' are significantly lower?


I want to reverse the polarity of my current source, which is a capacitor in this case, in the middle of discharging phase. Also the capacitor bank is being discharged through a coil to make a short time electromagnet. What I want is to reverse the polarity of that magnet in middle of discharge. How can I achieve this using MOSFETs or other fast switching components?  Below is the single polarity simple circuit. Also I'm using polarity sensitive capacitors in my capacitor bank.  I know that H-bridge would be the component in this situation, but I'd like to build my own "H-bridge" using n- and p-type MOSFETs to handle these high currents.         – Schematic created using

I'm working on a relatively simple Arduino project and want to reach an elegant solution for a circuit. I'm not sure if there is an existing IC for what I want to do, but here is a diagram for what I'm attempting to accomplish.  When googling the solution I found the name to be an ABBA circuit (tagged by minecraft sadly), essentially I have 2 inputs which need to be switched when a 3rd logic trigger is activated. Can I do this with a single device? Or is there a more complex solution?  More stats: +3V line has ~170 mA of current Logic Switch is a +5V line with ~47 mA of current (Digital pin)  Thanks for taking a look and I appreciate any help given.


In my model I have a class containing a rather generic function, which calls a higher order function. I put together a simple example of it:  class AClass(object):      def __init__(self, prop, fun):         self.prop = prop         self.fun = fun      def do_sth(self):         self.fun()  def namely_this_(context):     print 2*context.prop  obj1 = AClass(3, namely_this_) obj1.do_sth()   This snippet contains everything to know, just note, that it could be continued by something like:  def namely_this_2(self):     print 4*self.prop obj2 = AClass(2, namely_this_2)  obj2.do_sth()   The above code does not run, instead it throws a  TypeError: namely_this_() takes exactly 1 argument (0 given)   Instead, I have to change the do_sth to      def do_sth(self):         self.fun(self) # the *self* in the parenthesis added   Question: In what way does the namely_this_ differ from functions defined inside a class and is my workaround a viable solution?

I've read that it is possible to add a method to an existing object (i.e., not in the class definition) in Python.   I understand that it's not always good to do so. But how might one do this?


I am thinking that the RHS can be counted as $\binom{n}{k} + \binom{n}{k+1}$. But I don't how the following counting may go.

After reading , the most popular answer use the identity $$\sum_{t=0}^n \binom{t}{k} = \binom{n+1}{k+1}.$$  What's the name of this identity? Is it the identity of the  modified.  How can we prove it? I tried by induction, but without success. Can we also prove it algebraically?  Thanks for your help.    EDIT 01 : This identity is known as the  because, on Pascal's triangle, when the addends represented in the summation and the sum itself are highlighted, a hockey-stick shape is revealed.


I've installed Ubuntu 16.04 and effectively lost control of my computer which worked just fine under Ubuntu 14.04. I just need a simple command line instruction(s) so I can save my files on my 2tb backup drive, reformat my hard drive and start all over again. Even though I don't want to use it I've even lost access to the partitions with Windows 7 on them.

For some reason I can't boot my system. I get an error akin to Operating System Not Found.   I tried bootrepair, and that didn't work. So then I decided I would just save my personal files, wipe everything, and reinstall.   But in the live session, when I go to the /home directory, my username folder isn't there, instead it goes to the Live CD's desktop and other directories. Is there some other error occurring? Is there a way to recover the files?


My instructor stated that in order to have a valid proof by mathematical induction, you first have to show A(1) holds, and then assume A(n) to deduce A(n+2). Why is the first step necessary if we are going to assume A(n) though?   I get that showing A(1) is true suggests that A(n) might be, but that could very easily not be the case. Perhaps A(3) does not hold. So why logical benefit do we gain by proving A(1) before completing a more general proof by induction?

Learning about proof by induction, I take it that the first step is always something like "test if the proposition holds for $n = \textrm{[the minimum value]}$"  Like this:       Prove that $1+2+3+...+n = \frac{n(n + 1)}{2}$ for all $n \ge 1$.   Test it for $n = 1$:  $$n = \frac{n(n + 1)}{2} \implies 1 = \frac{2}{2}\textrm{, which holds.}$$  * The rest of the proof goes here *    So, I do it all the time (like a standard). But I never really thought about why. Why do I do such test? I can see that if the test does not hold, it cannot be proven by induction, I guess. But is there another reason we do this?


I am trying to prove that all analytic bijective map from $\mathbb{C}$ to $ \mathbb{C}$ has the form of $f(z)=az+b$ where $a$ is nonzero.  I tried to approach this problem by using taylor series and Cauchy integral formula, but how do I use the property of bijection?

How can it be shown that $$Aut(\mathbb{C})=\{f|f(z)=az+b,a\neq 0\},$$ where an automorphism of $\mathbb{C}$ is defined as a bijective entire function with entire inverse?  If $f$ is of the form $f(z)=az+b$, with $a\neq 0$, then obviously $f$ is in $Aut(\mathbb{C})$. How can I prove the converse?


$(B_t)$ is a Brownian motion and i assume that $s<t<u$ we have $$E[B_t |\sigma(B_s,B_u)] = G(B_s,B_u)$$ Does anyone knows the explicit expression of $G$ ? (the calculus is easy but fastidious...). Thank you.

Let $(B_t)_{t\geq 0}$ be a standard Brownian motion in $\mathbb{R}^d$. It is intuitive that, for fixed $s<t<u$  $$\mathbb{E}[B_t\mid \sigma(B_s,B_u)]=B_s+\frac{t-s}{u-s}(B_u-B_s).$$  However, I cannot think of a way to show this rigorously.   If first attempted to take $A\in\sigma(B_s,B_u)$ and show that $\mathbb{E}[1_A B_t]=\mathbb{E}[1_A(B_s+\frac{t-s}{u-s}(B_u-B_s))]$. But I cannot manage to show this equality.   I'd be very thankful for any ideas and suggestions on how to tackle this problem.


this is the code I have now:  \begin{tabular}{|l|l|p{8cm}|} \hline NB & Screen & Description\\ \hline \multirow{-40}{*}{1} & \includegraphics[scale=0.4, trim=0 0 0 -5]{CO600_Screenshots/Login-Accounts} & The first view is the Google Login Screen and has 4 buttons. \newline Selecting either of the accounts will take us to Screen 2, 'Add Account' and 'Remove' will take us to further Google screens which have not been documented. \\ \hline \end{tabular}   The large block of text after the \includegraphics is placed automatically at the bottom of the cell - I need to place it at the top.  I've tried to use the multirow package to do this but then the text extends out of the cell and stops wrapping.  Can anyone help?  Thanks!

I want to create a table with multiple rows of the following form: a cell that contains text and then multiple cells that contain images. The text should be vertically centered and the contents of every column should also be centered horizontally. I am aware of the m{} column type but somehow this seems to fail if an image is contained in the row and determines the row height. Any ideas?  Minimal example:  \documentclass{article} \usepackage{graphicx} \usepackage{array} \begin{document} \begin{figure} \begin{tabular}{m{3cm}c} (a) & \includegraphics{some_picture.pdf}\\ \end{tabular} \end{figure}  \end{document}


My central air conditioner isn't cooling like it used to. I noticed that the refrigerant lines entering the evaporator coil in the plenum were icing up. What might the problem be?

I noticed my house wasn't getting under 75°F this weekend when I had the thermostat set for 70°F. Since I'd done a lot of drywall sanding inside recently, my first idea was to replace the filthy air filter.    My first indication that the air filter wasn't the root cause was when the return didn't have enough suction to hold the air filter in place while I was replacing it. I went outside to look at the compressor unit and discovered the exposed portion of the refrigerant line running into the house was frozen, but the fan was still running. The evaporator drain line still had a steady stream of water coming out of it. After turning everything off and waiting for the line to thaw, I turned the thermostat back on. Cooler air came out of the vents, but it didn't seem to be blowing with much force, and it wasn't as cool as it should be. I went back outside and discovered the refrigerant line was already frosting up again. At this point it was already dark, so I turned everything back off and slept with the ceiling fan on. :/   Other random notes that may or may not play a factor:   The AC unit had been sitting idle the past 3 days since we had nice weather in the mid-70's last week. I mowed the lawn next to the condenser unit the day I noticed it stopped working. However, I was bagging the grass clippings, so nothing should have been blown into the unit.   Any ideas on the root cause of the icing and lower air flow? I wouldn't think the two would be connected normally. Is it something as simple as low refrigerant levels? I plan on going to look more closely at it after work today. What are some other things I should pay attention to?  UPDATE: I checked the system after work today and decided to give it one more chance after I couldn't find anything wrong with it. After a few hours, it had brought the inside temperature down from 80°F to 75°F. I periodically checked the refrigerant line for freezing, but it never got much colder than 60ish degrees.  I think the root cause was the air filter, and that I didn't allow enough time for the line to thaw last night.  UPDATE 2: Maybe I drew conclusions too soon - I just checked the refrigerant line and discovered frost on it again. The inside temperature was at 72°F while the outside was at 66°F. I think pumping warm air to a cooler outside temperature may have contributed to the icing, but I'm not completely sure. (And if you think I'm crazy for running the AC when I could just open the window, you'd think twice too if you saw how many bugs swarm my porch light and windows every night. Dozens of them somehow find their way past the screens if I open the windows.) I plan on running it again tomorrow during the day and monitoring the refrigerant line temperature every few hours. If it freezes up again, I think I'm going to cave and call a repair guy.  UPDATE 3:  I totally forgot to follow up on this. It froze again, so I called an HVAC repair guy. He checked the system, added refrigerant, and problem solved. I think the bill came out somewhere around $150 for the service call fee and refrigerant costs.


How do I show that my solution to the congruence is the only solution? I'm asked to solve, $\mu,\lambda$ that satisfy $$89 \lambda+55 \mu=1$$ Using Euclid's algorithm I found $\lambda=-21,\mu=34$. Then I'm asked to find the solution to $$89 x \equiv 7\pmod{55}$$ Using $\lambda 89 \equiv1 \pmod{55}$ I found that $7\lambda89 \equiv7 \pmod{55} \implies x=7\lambda +55k$ for $k\in \mathbb{Z}$. But how do I show, that this is the only solution to the congruence?

I want to ask a question about modular arithmetic. I know, that modular multiplicative inverse exists only if modulo and integer are relatively prime. I want to know, are there any ways of division in modular arithmetic, if modulo and integer aren't relatively prime? I tried to find info about that, but failed.


I am using multiple tools developed by the  which are not configured via a config file but via their source code (in this case C) and then simply installed through make install. So I am maintaining my own repos (need continuous changes) of these programs. The question is where should i put these repos? Directorys like /usr or /usr/local/share are for reference purpose. Is it /opt, /srv or should i just collect them somewhere in my home directory?

Is there a standard location in Linux for holding source files for example OpenSSL. I am building Nginx from source with non default version of OpenSSL. I need to download and untar OpenSSL and I did it in home directory. Now, I wonder is there a standard location in Linux maybe /opt ?


Based on what I have learned (and also this article:  as well as the original 1995 paper), BH procedure requires specifies a FDR-value threshold. However, I have seen reported raw "adjusted pvalues" that simply adjust pvalues using BH, without specifying the procedure a FDR threshld. How precisely is this done without specifying the FDR threshold? (Previously asked here:  but with no answer)

I understand the procedure and what it controls. So what's the formula for the adjusted p-value in the BH procedure for multiple comparisons?    Just now I realized the original BH didn't produce adjusted p-values, only adjusted the (non) rejection condition: . Gordon Smyth introduced adjusted BH p-values in 2002 anyways, so the question still applies. It's implemented in R as p.adjust with method BH.


The family has two children. We know that one is Jack(boy). What is the probability that the other child is also boy? The ratio of the number of newborn boys and girl 107:100 (boys are more).  My solution:  If is one boy, we have 4 options:  Jack-girl 1/4=0,25   girl-boy 1/4=0,25  Jack-boy 1/4=0,25  boy-Jack 1/4=0,25  Only two options can be, in this case is probability 2/4=0,5  The probability of the birth of a boy - 107/(107+100) = 0,5169  The probability of the birth of a girl - 100/(107+100) = 0,4831  The probability that two boys are born for each other is 0,5169*0,5169  The finally probability that the second child is also a boy  0,5*0,5169*0,5169 = 0,1336  Is this solution correct?

A man visits a couple who have two children.One of them, a boy, comes in to the room. Find the probability p that other is also a boy  a) 1/3 b) 2/3 c) 1/2 d) 3/4  Correct Ans: a) 1/3  However I am getting answer as 1/2.My solution is as follows.  The couple has two children, hence the sample space is as follows.  B- Boy G - Girl  BB BG GG ( BG and GB mean the same thing as Girl,Boy), but it is already known that one is boy.So the sample space reduces to  BB BG  So now p is 1/2  Is there some mistake is my approach ?


I have a Nikon D3300 and I want to do astro-photography. I have a 50mm prime lens and by the , I can click only up to 6.6 seconds without having star trails. Any idea how I can do it without buying any other lens?

I want to take pictures of  or  or , but I don't have an equatorial tracking mount, and don't want to spend that much money on one.  How can I get clear, low-noise shots of things in the night sky without noticeable motion blur, without spending too much money? Is it possible to build a DIY tracking mount? Are there other techniques or devices that could help?


In the last year I had a problem with my notebook: sometimes when I push the power button it starts (I hear the fan) but nothing appears on the screen, I have to hit it on the bottom to make it start..  In the last month the problem changed: now it starts every time without need of hitting it but it shuts down without any apparent reason and then immediately reboots. This happens more frequently when the notebook is JUST turned on or when is turned on from a while but I am not using it. In addition if I instead boot Windows (installed on another partition) the problem disappears...    My hypothesis is that the problem is in the hard disk, so I came to the questions:   How can I verify my hypothesis? Is it plausible? Since Windows in in sda2, Ubuntu in sda5 and sda3 contains only data do you think it is a good idea to move Ubuntu to the left (resizing sda3) and then leaving the last part of the disk (where probably there is the problem) empty (in a new partition)?

I've run across (personally or by proxy) a bunch of storage media that exhibited physical problems during their life. Hard disks, solid state drives and other flash storage media all fail after some time. The situation is worse with USB flash drives and flash cards because of the large amount of suppliers with inferior flash cell and flash controller quality.  How can I reliably detect if a storage drive suffers from physical damage?  Note that this question isn't about file system integrity (which can be checked with ).


This code was written in Scala.  Is it possible to write it in Python using built-in functions?  Scala Code:  List(1, 2, 3, 4, 5, 6, 7, 8, 9).grouped(4).toList.map { group =>     println("begin")         group.map { item =>             println(item)         }     println("end") }   Result:   begin 1 2 3 4 end begin 5 6 7 8 end begin 9 end   I tried, but didn't succeed.

I have a Python script which takes as input a list of integers, which I need to work with four integers at a time.  Unfortunately, I don't have control of the input, or I'd have it passed in as a list of four-element tuples.  Currently, I'm iterating over it this way: for i in range(0, len(ints), 4):     # dummy op for example code     foo += ints[i] * ints[i + 1] + ints[i + 2] * ints[i + 3]  It looks a lot like "C-think", though, which makes me suspect there's a more pythonic way of dealing with this situation.  The list is discarded after iterating, so it needn't be preserved.  Perhaps something like this would be better? while ints:     foo += ints[0] * ints[1] + ints[2] * ints[3]     ints[0:4] = []  Still doesn't quite "feel" right, though.  :-/ Related question:


I Used the "install ubuntu alongside windows boot manager" option to download ubuntu yesterday (after hours of confusion from reading about manually adding partitions).  I think I allowed 65GB (using the slider during installation) for Ubuntu and the rest for Windows. (I have 300GB usable HDD space).  After it finished installing, I tried booting in to each OS and they worked perfectly. The problem is, I am unable to see any of my Windows files and documents from Ubuntu.  When I click that Hard drive icon on Ubuntu, I get this:  Error mounting /dev/sda4 at /media/atlanta-thinkpad/BED68EB6D68E6F09: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=1000,gid=1000" "/dev/sda4" "/media/atlanta-thinkpad/BED68EB6D68E6F09"' exited with non-zero exit status 14: Windows is hibernated, refused to mount. Failed to mount '/dev/sda4': Operation not permitted The NTFS partition is in an unsafe state. Please resume and shutdown Windows fully (no hibernation or fast restarting), or mount the volume read-only with the 'ro' mount option.   Edited:  I can now see the ubuntu partitions after diabling fast startup in windows, but the partitions are empty.

Whenever I boot Ubuntu, I get a message that it cannot mount my windows partition, and I can choose to either wait, skip or manually mount.  When I try to enter my Windows partition through Nautilus I get a message saying that this partition is hibernated and that I need to enter the file system and properly close it, something I have done with no problem so I don't know why this happens.    Here's my partition table, if any more data is needed please let me know.     Device Boot      Start         End      Blocks   Id  System /dev/sda1            2048    20000767     9999360   83  Linux /dev/sda2        20002814   478001151   228999169    5  Extended /dev/sda3   *   478001152   622532607    72265728    7  HPFS/NTFS/exFAT /dev/sda4       622532608   625141759     1304576   82  Linux swap / Solaris /dev/sda5        20002816   478001151   228999168   83  Linux


My texture has some black text (on right side of picture,) and also a transparent background. But the text also is transparent?!? Plus I must keep the text black.  Picture:  Please help.

I'm designing this animal-type creature, and want to add a transparent .png image to its face with the face features (object has a subsurf). On the left is the image with the features, on the right is the part of the object where I want it to be.    I tried to import the image as a plane, but matching the shape of the plane with the face didn't work, and the lines of the face left shadows on the head, and could be seen as a different object from some angles (although it's the closest I've gotten yet). It looked like this:    So , I tried selecting the faces of the head that the features should go over, and create a new material for it. Unfortunately, since the .png is transparent, the result produced was this:    (where it's impossible to tell the transparency from a black background default color, and where I wouldn't know where to start to adjust size and position).  I also tried UV mapping, but then the whole object became black with the features repeated all over.   Is it something I have to go into Nodes for? I'm kind of stuck here. Creating a new material and applying it is simple, but applying a material that is an image is a bit more complex it seems... Ideally, I would reproduce the same technique for the adhesive bandage on its arm (seen on the right of image 1).