Is it possible to boost the signal of my wifi, i keep getting disconnected from xbox live.  I do not wish to boost the range (loads of products state range) of the signal but the actual connection strength of the signal. is this possible?

I had Windows 10, then 1 day my wifi range dropped. It shows only one signal when I'm on the same floor of the router, and no signal found when even go out of the door. For many other reasons (and for this one too) I switch from Windows 10 to Windows 7. But the problem is same. I tried to update the drivers but nothing happened.  It also sometimes shows Limited Access and a yellow triangle on network indicator, but all the other devices connected via that network (wired AWA wireless) showing Internet Access and also fine range. So it may not be the problem of the router. I can't even open the router page (192.168.0.1) when Limited Access shown. So I think It's not the internet, but the router is not connected to my system.  Here's my WIFIcard: Realtek RTL8723BE 802.11 bgn Wifi Adapter  What I do is troubleshoot the problem and after waiting 10-18 seconds my internet came back.   Is it my system's hardware problem or something else? Can I resolve this thing?


I have a form that sends datas to my DB. However I want to make sure it is safe. I used to use htmlspecialchars($variableToSecure) But I learned it is not enough (protects only from html injections) I searched on internet and found mysql_real_escape_string($variableToSecure) But this one is obsolete and doesn't exist since php 7.0 I wish to know what is the best way to secure a variable now?

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


I just can't manage to make the cursor and origin in the picture to go to the centre of my mesh, I press all the option on shift+s and nothing works.

So, I'm working creating a lamp... yes, newbie here.  After modeling for a bit, I noticed that my point of origin was no longer the center of my object:    How to I reset an object origin point to the center of it's geometry?


I have bibliographical references ordered in a spreadsheet and I want to create a .bib file to use then in latex documents. I have found the way to transforma a .bib file into a csv, but not the inverse.

I'm seeking a way to get my books database, stored on , into BibTeX form. As near as I can tell, Goodreads provides no support for this directly, but does provide for  (on the right). Are there tools I could used to import from the CSV file into BibTeX?    FWIW, the fields exported by goodreads are  Book Id,Title,Author,Author l-f,Additional Authors,ISBN,ISBN13,My Rating,Average Rating,Publisher,Binding,Number of Pages,Year Published,Original Publication Year,Date Read,Date Added,Bookshelves,Bookshelves with positions,Exclusive Shelf,My Review,Spoiler,Private Notes,Read Count,Recommended For,Recommended By,Owned Copies,Original Purchase Date,Original Purchase Location,Condition,Condition Description,BCID   and I can, of course, easily rearrange their order or convert to other delimiters.


I need to prove that $a_{n} = (1^{2} +2^{2} + ...+n^{2})^{n} >n^{n}(n!)^{2}=b_{n}$ for any natural number n.   Proof:  Note that by the arithmetic-geometric mean inequality,$\frac{1^{2} +2^{2} + ...+n^{2}}{n} > (1^{2}\cdot 2^{2}\cdot...\cdot n^{2})^{n/2}$. Then $1^{2} +2^{2} + ...+n^{2} > n(1^{2}\cdot 2^{2}\cdot...\cdot n^{2})^{n/2} = n(n!)^{n}$. This implies that $a_{n} =(1^{2} +2^{2} + ...+n^{2})^{n} >n^{n}(n!)^{2n} \geq n^{n}(n!)^{n}= b_{n}$. Then we conclude that $a_{n} > b_{n}$ for all natural numbers $n$.  Is there anything wrong with my proof?

I am getting crazy with this one.     Suppose $a_n=(1^2+2^2+3^2+\ldots+n^2)^n$ and $b_n=n^n(n!)^2$. Show that $a_n>b_n$ for all $n$.    They suggest to use the AM-GM inequality.


I am learning development on osx and ios. So far, coding is ok. The most difficult is to handle all the files, all the configuration issues (of xcode), and so on. I thought hearing from a guru about libraries/frameworks would help me a lot!  I would like to know more about libraries and frameworks.    What is a library, what is a framework (and what's the difference between them)? Where can I find a list of all the frameworks (of all the libraries?)? Or: what are the most important frameworks? What can I do without any framework?

What is the difference between a framework and a library?   I always thought of a library as a set of objects and functions that focuses on solving a particular problem or a specific area of application development (i.e. database access); and a framework on the other hand as a collection of libraries centered on a particular methodology (i.e. MVC) and which covers all areas of application development.


Why is participating in meta a privilege in Stack Overflow?

I have enough reputation to open a meta question in one community, but I don't have enough reputation to open a meta question in a different community.   I thought the point of requiring some reputation was to filter out spammers, wouldn't some reputation in any community show that a user isn't a spammer?


Do the Kryptonians have the same life expectancy as humans?  Does their life expectancy differ while being on Earth?  We see Superman go from childhood to adulthood quite normally but does it mean he moves to old age the same as us?  Is there a difference between the duration of his adulthood and ours as he seems to have a similar adolescence??

Assuming Superman doesn't die in battle, and lives out his life under the effects of our yellow sun, what is his expected lifespan? Has DC Comics ever provided or suggested an answer?


R is a commutative ring with an identity element.  Prove or disprove that if   $a \in R ,\; a \neq 0 \;$and is not invertible  so  $a$ is a zero divisor.  I tried to pick $\;x \in R,\; x\neq 0\;$ s.t $\;ax = 0$  My first try led me to pick $\;x = ax-x$  $ax = a(ax-x) = a^2x - ax\;$ Then I thought that if i could prove that $\;a\;$ is idempotence I could prove that $\;ax = 0$

In $\mathbb{Z}_n$ the elements are fully partitioned between the units and the zero-divisors. I believe this is the case, am I correct?  Now, I take it this does not hold true in general, there may be rings with elements that are neither units nor zero divisors?


Fragmented memories:   A space station is discovered. May have been a by team of people who get split up? They board the space station. The space station is uninhabited. As they explore, the rooms start getting larger and larger. Eventually the last room is found which is actually the entire universe. I think it was written in the 70s.

I read it online few years ago. It is a short story about exploring a spacecraft/ship/station that seems to be infinite inside.  It is written like a log, and each entry starts with a measure, like Day 1 "1 km", Day 2 "10 km", Day 3 "100 km" (not sure about dimensions but they grew exponentially).  I found the story at that time while reading about megastructures. Although the construction in the story was huge, it didn't fit the criteria of megastructure because it was infinite.


I have seen the following sentence in a published book:  Sentence A There were a toothbrush, a piece of floss, and a tube of toothpaste.  It sounds wrong to my ear. I would write  Sentence B There was a toothbrush, a piece of floss, and a tube of toothpaste.  This is because I believe the verb should agree with the nearest noun, i.e., "a toothbrush".  Is the original sentence correct, or are both versions correct? Many thanks

It seems I put a   Bounty assigned by outside party, two lengthy, reference-citing answers, one "-1" (awarded the bounty), one "-2", two others scored "0" and "-2" respectively, the answers suggesting one or the other is correct, 73 comments and no consensus so far - and me, as the asker, lost without a clue what to think of the answers anymore -  this is no longer "Learners' Level" question, so I thought I'd bring it here and hear what the experts have to say.    Original question:  Plurality of verb depending on plurality of list elements  An edit was suggested to my sentence.     There was were an orange, some grapes, two apples and a small pile of cherries on the plate.   In my native language plurality of the verb always follows plurality of the first element on the list. There were an orange,... sounds awkward to me, no matter what follows up. My simple solution was reordering:     There were some grapes, an orange, two apples and a small pile of cherries on the plate.   But that's not the first time I faced this situation and I'd like to know what the rules of grammar say about that - was my editor overzealous or am I trying to copy rules of my language that don't apply in English?    Someone linked a  for negatives, where the situation is more clear-cut ("There is no..."). Same applies to connection with "or" apparently, per accepted answer there. Still, nothing for "and".  It seems there is a consensus that in that if the verb goes after the list, it will be plural.     an orange, some grapes, two apples and a small pile of cherries were on the plate.   There doesn't seem to be clear consensus for:     On the plate { was | were } an orange, some grapes, two apples and a small pile of cherries   Adding more to the confusion is the abbreviated form: "There's"     One last note. In North America, at least, there is a widespread use of using a singular form like "there is" and "there was", without regard for the subject item or items, and this "there is" is often shortened to "there's":           There's three apples on the table!      Could you please clarify this mess?


I saw this photo on my social network.  The ambiguous expression $6\div2\times3$ yielded 2 different answers.    The difference is the order of operations. If the division's done first then the answer is 9. If the multiplication was first then the answer would be 1.  What is correct?  There are rules for the  like "BODMAS" for example (I use it) but it doesn't say what is correct in such situation.  Is it possible that both answers are correct unless "brackets" are specified? Or is there one correct answer? Is there a rule for the "direction" in which those must be done? "left to right" for example?  edit: It looks like it's known that it should be done from left to right but the question now is whether:   It's just a convention. It's a definite rule that makes us say that one of the answers is wrong.   tag should be "operator-precedence" for example. Help me with the tag please :)

Possible Duplicate:          Please, look at the picture?    Which calculator shows true result and how to prove achieved result?


I have just installed a brand new debian buster: $ lsb_release -a No LSB modules are available. Distributor ID: Debian Description:    Debian GNU/Linux 10 (buster) Release:    10 Codename:   buster  $ cat /etc/profile  [..] if [ "`id -u`" -eq 0 ]; then   PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" else   PATH="/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games" fi export PATH  [...]  $ whoami  zozo $ su  Password: # id -u  0 # printenv | grep -i ^path  PATH=/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games  If I run as root:  # grep -i path /etc/profile.d/* no output # grep -i path ~/.profile no output # grep -i path ~/.bashrc no output  Being on a Debian system there is no ~/.bash_profile nor ~/.bash_login vi ~/.profile  PATH="/usr/bin:/bin:/usr/sbin:/sbin"  but the problem remains: Ctrl+D to get back to normal user then $ su  password:   # printenv | grep -i ^path PATH=/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games  So I made some searches:  then if [ -z "$PS1" ];then echo NOT interactive shell ;else echo INteractive shell ;fi INteractive shell  it says:  When Bash is invoked as an interactive login shell, [...] it first reads and executes [...] /etc/profile [...]. After [...] it looks for [...] ~/.profile ...  So I am wondering why it does not load PATH from ~/.profile (~/.profile is not called/loaded). Of course, if I put it in ~/.bashrc, it works. So, at the end, by default, no path for essential commands like shutdown or reboot. Furthermore, I am realizing that tools like systemctl, which are by essence an administration commands are located in /usr/bin instead of /sbin or /usr/sbin  (and many other admin commands, like getfacl, setfacl... but that's another problem). I should have missed something here.

According to the answer to  on Ask Ubuntu, GNOME Terminal is a type of non-login shell. As pointed out in the excellent book, A Practical Guide to Fedora and Red Hat Enterprise Linux, 6th Edition:  an interactive non-login shell executes commands in the ~/.bashrc file. The default ~/.bashrc file calls /etc/bashrc.  As a result, /etc/profile won't be processed in a non-login shell. However, I found that I have appended the java home path to the PATH variable and, when I use GNOME Terminal and issue the command java, everything goes fine. Also, the value of the PATH variable is the same as the value I defined in /etc/profile. In view of the above-mentioned facts, there is a conflict, what’s wrong with my understanding?


My Work:  If you take the cartesian product of any set with two arbitrary elements $a$ and $b$, and the resulting set is $\{\{x_1\},\{x_1,x_2\}\}$, then the only possible values for $a$ and $b$ are $x_1$ and $x_2$ by definition of the cartesian product.  This answer seems overly trivial and I think I'm doing something wrong. Please help!

My book says  \begin{equation} (a,b)=\{\{a\},\{a,b\}\} \end{equation}  I have been staring at this for a bit and it doesn't make sense to me. I have read several others posts on this, but none made any sense to me.  For example,   Based on how my ignorant brain is viewing this, I don't see why the definition could not be.  \begin{equation} (a,b)=\{\{a\},\{b\},\{a,b\}\} \end{equation}  aka the power set. What is the significance of the {a} in that definition? Please keep things simple if possible. Normally definitions have a valid and clear reason for being defined that way.    Clarification  First, I understand what an ordered pair is. I just don't see how the set notation says that.   Second,  \begin{equation} (a,b) = \{\{a\},\{a,b\}\}=\{\{a,b\},\{a\}\} \end{equation} Sets don't preserve order, but ordered pairs do. How does the third part of the equality apply to the definition?  Third, another issue with the notation that I have starts with the Product Property of Sets  \begin{equation} \text{Let $X$ and $Y$ be sets} :\ X=\{a,b,c\}\text{ and }Y=\{a,d,e\}. \end{equation} \begin{equation} \text{Then }X \times Y = \{(a,a),(a,d),(a,e),(b,a),(b,d),(b,e),\dots,(c,e)\} \end{equation} If we look at the first ordered pair and our given definition we have  \begin{equation} (a,a)=\{\{a\},\{a,a\}\} \end{equation}   How can this be so, you can't have duplicates in sets? I guess what I am looking for in an answer, is not a proof or a definition of ordered pairs, but rather something like, "This notation says what it says because...". Except for the second to last point I get the terminology, I just don't get the connection between the two different uses of notation.


A C++ beginner here! :-) I was trying to write a function by mimicking those in STL algorithm.  template<class InputIterator> InputIterator findNegativeMax(InputIterator, InputIterator);   The above is the declaration in some.hpp file. And below is the definition of the function findNegativeMax().  template<class InputIterator> InputIterator findNegativeMax(InputIterator first, InputIterator last){     Iterator position = nullptr;     while(first <= last){          /*some logic*/     }     return position; }   As stated earlier I tried to mimic the STL code like  . but when I compile the test code which looks like  int main(){ std::vector<int> vec = {1,2,3,44,4,-5,-5,-2}; auto it = algo::findNegativeMax(vec.begin(),vec.end()); std::cout<<"position::"<<*it<<std::endl; return 0;   }  .But when compiling with all necessary objects and attributes included I'm getting the following error  /tmp/ccma7n9Q.o: In function main': testAlgo.cpp:(.text+0x87): undefined reference to__gnu_cxx::__normal_iterator > > algo::findNegativeMax<__gnu_cxx::__normal_iterator > > >(__gnu_cxx::__normal_iterator > >, __gnu_cxx::__normal_iterator > >)' collect2: error: ld returned 1 exit status  Please pardon if the question is in anyway misformed.  Thank you in Advance.

Quote from :     The only portable way of using templates at the moment is to implement them in header files by using inline functions.   Why is this?  (Clarification: header files are not the only portable solution. But they are the most convenient portable solution.)


I've been reading  to help me understand how AES works. In  picture it says:  I take each column and mix the bits in it.  But then never explains how he mixes the bits. I've been searching for a while, but can find nothing about it. Can anyone explain what is happening in this step?

Section 3.4.3 "The MixColumns Step"(page 39) of , it states     The columns of the state are considered as polynomials over   $\operatorname{GF}(2^8)$ and multiplied modulo $x^4 + 1$ with a fixed polynomial $c(x)$.      The polynomial $c(x)$ is given by   $c(x) = \mathtt{03} \cdot x^3 + \mathtt{01} \cdot x^2 + \mathtt{01} \cdot x + \mathtt{02}$      Let $b(x) \equiv c(x) \cdot a(x) \pmod{x^4 + 1}$. Then         How this polynomial multiplication modulo $x^4+1$ is converted to Matrix Multiplication?


I have tickets for the Wimbledon final, scheduled on 15 July, obtained through the online ballot. I am a government employee (since 28-6-2016), working as an assistant engineer with a net salary of 41000 INR. I had been refused a visa, even after submitting bank statements (8 months), my Wimbledon ticket offer, pay slips (7 months), Form 16 for the last two years, NOC and leave sanction, appointment letter, accommodation proofs. What are my chances if I apply again as the date of travel is closer? Is it better if I opt for Premium Service?  If you look at the refusal letter they have miscalculated the closing balance 3,75,000 is roughly 4175 pounds.I have paid for the wimbledon finals and received conformation i have provided all the evidence in support.I have a genuine reason but still refused..

Many of the UK visa refusals we see here share a common pattern and the prevailing reasons refer to V 4.2 (a) and (c).    I do understand that, while the applicants may describe very different individual circumstances, there's a consistent pattern and, broadly, fall into specific categories:    Credibility (lifestyle, lack of ties, visit history, lies & omissions) Funding (insufficient funds, provenance of funds, funds parking) Sponsorship (family, friends, employer)   Question: What most commonly triggers a UK visa refusal where V 4.2 (a) and (c) are given as the grounds?  Secondarily: Given that there is a clear pattern, to what extent are these refusals predictable? Does sponsorship make a difference? Is there a set of personal circumstances, however abstract, where a refusal is all but guaranteed? For example, why do those we see here on TSE who sought entry for the PLAB or British Army appear to be refused with a common theme? Is there a uniform shortcoming or is it just discrimination?   PLAB: What is about applications for a visa, for the purpose of sitting the Professional and Linguistic Assessments Board (PLAB) exam, that seem to invite refusals. After all, the test is given so that international medical graduates can show that they qualify to practise medicine in the UK. The first part, PLAB 1, can be taken in centres outside of the UK. However, PLAB 2 can be taken only in the UK. Why can't you can't get a visa just to sit the exam, promising that you'll leave immediately after?    British Army: Since Commonwealth citizens are eligible to apply online to join, even those who don't reside in the UK, why is it so difficult to get a visa just to attend an interview to see whether you are suitable? Even with an invitation from the Army, such visa applications seem to be unsuccessful. Isn't a career in the British Army a valid reason?     Lastly:  After such a refusal, what approaches would increase the chance of a successful application?


I am a teenager who plans to start a Minecraft server. I live in the United States and I assume that I will need to pay taxes.   My parents want to find out more about the taxes. I've read a couple of things but I'm not sure what to do. Obviously I want to pay as little as possible.  How do I do this? Also what kind of taxes does the server count as?

I run a Minecraft server and there is a donation button so players can help support the costs. I pay out of pocket for the rest, it's $125/mo.  The money they donate goes right to paypal which is where the automatic payment to the server happens, so it works out nice as it will just pull the remaining amount from my account.  Do I need to claim the donations as income? Can I somehow write off the server costs? Etc.


I have cloned my current Ubuntu installation onto a bigger hard drive using clonezilla, but the amount of free space is still the same as before.   So I did some searching and found out that I have to use gparted to make the new space available. But I'm not quite sure how to use gparted to do this.

Previously, I have installed Windows 7 on my 320 GB laptop with three partitions 173, 84 and 63 GB each. The 63 GB partition was where the Windows was installed. The rest were for file containers.  Now I changed my OS to Ubuntu 12.04 LTS. I installed Ubuntu by replacing the entire Windows 7 on the 63 GB partition. The rest of the partitions remain as an NTFS Windows partition and I can still access them both (the 173 and 84 GB partitions).  Now I want to change the two partitions of Windows into an Ubuntu format partitions plus most importantly, I want to extend the 63 GB partition to more than a 100 GB because at the moment I am running out of disk space. Whenever I try to install any application, especially using wine, it always complains for a shortage of disk space.  How do I do the extending activity before I entirely format my laptop again and lose all the important files on my partitions?


I have this in my .htaccess file:  <IfModule mod_rewrite.c> RewriteEngine On RewriteBase / RewriteCond %{HTTP_HOST} ^www\.(.*)$ [NC] RewriteRule ^(.*)$ http://%1/$1 [R=301,L] RewriteEngine On RewriteCond %{REQUEST_FILENAME} !-f RewriteRule ^(.*)$ app.php [QSA,L] </IfModule>   It rewrites both, http://www.site to http://site, and site to site/app.php I also want to rewrite site/index.php to site/app.php. How can I do it? When I request /index.php I get a 404 response.  I've tried to rename app_dev.php to index.php en my local host, but doesn't work. I've done the next change in .htaccess:  order allow,deny allow from all <IfModule mod_rewrite.c>   RewriteEngine On   RewriteCond %{REQUEST_FILENAME} !-f   #   RewriteRule ^(.*)$ /app_dev.php [QSA,L]   #line deleted   RewriteRule ^(.*)$ /index.php [QSA,L]         #line added </IfModule>   and rename the file app_dev.php to index.php

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


I have a small server at home, which has postfix installed.  It's only use is to return the results of cronjobs and email out externally for a few other scripts.  I use my ISP's mail server as a relay host.  It recently came to my attention that the mail server was acting as an open relay.  I fixed that problem by closing incoming port 25 on the router and reconfiguring postfix to only accept outcoming mail from the server.  I have checked with nmap externally from the LAN and tried various open relay tools and everything seems fine.  The problem is that I am still getting mail trying to be sent.  I have temporarily set the relay host to 127.0.0.3 (non-existent) to stop things being sent out and have set up iptable firewall rules on my server to prevent outbound port 25, so nothing is actually going out.  I thought the queues might still be full so I did:  sudo postsuper -d ALL deferred sudo postsuper -d ALL   But the mail keeps on coming in with the following log messages:     Dec  1 12:04:56 server postfix/pickup[3267]: E18411FA4: uid=33 from=   Dec  1 12:04:56 server postfix/cleanup[3274]: E18411FA4: message-id=<20111201120456.E18411FA4@server>   Dec  1 12:04:56 server postfix/qmgr[3268]: E18411FA4: from=, size=15619, nrcpt=1 (queue active)   Dec  1 12:04:57 server postfix/error[3304]: E18411FA4: to=, relay=none, delay=0.17, delays=0.1/0/0/0.08, dsn=4.4.1, status=deferred (delivery temporarily suspended: connect to 127.0.0.3[127.0.0.3]:25: Connection timed out)   So the question I have are:   How to determine where the incoming mail is coming from? i.e. which program on the server or from which other ip-address. What other ways can I debug this problem? Do you think I've been hacked and my server is compromised?

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


I have more than 10 different topics on my homepage. The titles are all wrapped around h1 tags.   I've heard so much about how bad it is to have multiple h1 tags on a page, that I wonder if this will affect a website's SEO negatively? If yes, how do I solve this problem?

Is is true
 tag should not have more than 1 on every page for SEO?   Every pages on the header, it includes and
 tag. Website Name which show an image from logo class, like this:

      Website Name

   and I also include
 on the contact page, help, etc and article page for example:
Contact Us

Name of the Article Title here
   On the homepage, it just has one
 for the logo Site Name... other pages have 2
 tags


When my Mac starts I want to automatically start a batch script called run.sh in the folder myfolder. When I start Automater I only find options for AppleScript and JavaScript.

We are trying to have a simple drive mapping script start up for ALL users on a Mac Mini. What's the simplest way of going by doing this? I've tried creating a .plist in Lingon and adding it to the Library LauncherDaemons and LauncherAgents folders, but it's not starting up. Any ideas? Is there a way to do this in the Terminal? The script by itself works fine and works if we add it to the Startup Items in System Preferences, but we want this to be automatic and for all users.  Thanks.


I wanted values like -  1,1.02,1.04,1.06,1.08 etc... So used numpy in python:  y = [x for x in numpy.arange(1,2,0.02)]   I got the values-  1.0, 1.02, 1.04, 1.0600000000000001, 1.0800000000000001,   I have three questions here:    How do I get exactly values 1,1.02,1.04,1.06,1.08 etc.... Why correct values for 1.02, and 1.04, and not for 1.0600000000000001,  How reliable our programs can be when we can't trust such basic operations in programs that can run into thousands of lines of code, and we do so many calculations in that? How do we cope with such scenario?   There are very similar questions that address problems with floating points in general and numpy library in particular -       While they address why such a thing happens, here I'm concerned more about how do I deal with such scenario in everyday programming, particularly in numpy python? Hence I've these questions.

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


Let $n\geq 2$, $A=[a_{ij}]\in Mat_n(\mathbb{R})$ the matrix defined by $a_{ij}=0$ if $i=j$ and $a_{ij}=1$ if $i\not =j$   Calculate $\det(A)$  Proof:  Sylvester's theorem:   Using Sylvester's determinant theorem, which says that for any rectangular matrices of mutually transposed shapes $A\in\mathrm M_{n,m}(K)$ and $B\in \mathrm M_{m,n}(K)$ one has $$\det(I_n+AB)=\det(I_m+BA).$$  If $N$ is your matrix then $-N=I_n-AB$ where $A\in\mathrm M_{n,1}(K)$ is a one column all-one matrix and $B$ is its transpose. Then  $$ \det(N)=(-1)^n\det(-N)=(-1)^n\det(I_1-BA)=(-1)^n(1-n). $$ I need an explanation about one part of the proof  Question:     I don't see this step:      $(-1)^n\det(I_1-BA)=(-1)^n(1-n).$

How do I calculate the determinant of the following $n\times n$ matrices  $$\begin {bmatrix} 0 & 1 & \ldots & 1 \\ 1 & 0 & \ldots & 1 \\ \vdots & \vdots & \ddots & \vdots \\ 1 & 1 & ... & 0 \end {bmatrix}$$  and the same matrix but one of columns replaced only with $1$s?  In the  above matrix all off-diagonal elements are $1$ and diagonal elements are $0$.


I really want a drawing tablet with a display. So far I've looked at the iPad Pro and Cintiq models. But I keep getting caught up in reading reviews, articles, blogs, etc., about each product that I keep forgetting to think back to core of what I'm looking for. I wish there was a person who knew everything about every product I could chat with, but a design forum is probably the closest I will get. I would be using the tablet for mainly sketching, illustrating, graphic design, and MAYBE animation. Here is a list of capabilities I'm looking for in a tablet (having no experience. Some of them might not even exist). (Features of high importance to me **)   ** Display tablet (visual screen built in) ** Accurate touch point with virtually no lag ** Wide scope of pressure sensitivity ** Wireless capabilities (Wi-Fi, Bluetooth, power. For sending files to my computer, working remotely without a power source, etc.) ** High definition, retina display, etc. ** Work directly in my Adobe programs (Photoshop and Illustrator at the LEAST. I also use InDesign, After Effects, and Flash) * Use the tablet for other things, browsing web, games, Netflix, etc. (probably only iPad, huh?) * Hook up with keyboard (I'm just thinking about shortcuts while using Adobe) * Touch capabilities (I like the idea that I could move around the screen with my fingers, zoom, in, etc. I watched some videos on Cintiq and iPad Pro, and this would be amazing. But since I've never used a drawing tablet, I'm not sure how much of a pain not having it would be) Ability to use as a mouse (I love using the Wacom Intuos. It would be nice to have the choice of working solely within my tablet, or on my MacBook while using my tablet as a mouse) Screen protector that fits? For protection and maybe give it that rougher paper texture Save files directly to the device   I know that this list is kind of insane, but I know I'm going to spend a pretty penny on this device and I want to make sure all (or most) of my needs are met. I'll probably go to Best Buy to try some tablets out and talk to someone who knows a little bit about what I need, but I'd rather here opinions from people in my field or any design-related field who has experience using tablets.

I do some caricature, cartoons and illustrations, as hobby. I believe that I am okay'ish with pen and paper, but recently decided to go digital.  Given my budget, and a quick assessment of needs and reviews of various graphic tablets, I am thinking of ordering the Wacom Bamboo One CTE 660 Pen Tablet which as per specs is a wide-format 8.5"x5.5" entry-level tablet.  During my research I've found that I could potentially use it with Inkscape, since I am not in a position to make an investment in professional software. Although I am not aware of the real potential of Inkscape for my purpose. I think I can mostly make-do with vector-graphics, and occasionally embed bit-maps (s.a. for scene background).  My question is -   Since the table is of a particular size, which is roughly half or sometimes even a quarter of the paper size I use normally, would the experience be very different ? Given that I'd be using vector graphics, can I assume that "free-hand drawn" images will scale-up nicely? What are the other "free" (as in beer) alternatives for my purpose/use-case? Ideally, I'd prefer something that is not very resource hungry, as my PC isn't very powerful (yeah, living with a lot of constraints!).   Edit:  Finally I went ahead and got myself a Wacom Bamboo One 'Medium' (6x9) tablet. It is the entry-level product, but based on my first day experience, I think it is quite nice. I wasn't expecting anything pro-grade, but it seems to be pretty adequate. Build quality seems reassuring (i.e. not cheap, flaky plastic), is quite sleek, and pretty responsive. It worked out of the box. Without drivers, on Win 7, it worked as a mouse right-away. Worked in MS-Paint as expected (as a pen). On installing drivers and software, I got pressure-sensitivity and something called Bamboo-dock. It seems like a Widget-container, i.e. you can download applications online... pretty much the same crop that you see on Firefox, Opera, Chrome -- but seemingly hand-picked, and pretty relevant to usage with a pen. I like SumoPaint, which I've used before, and is not bad for decent drawings / illustrations.  Getting used to Pen, as a navigation / desktop-pointer tool, takes some getting used to. I think touch-phones and touch-pads have already mentally tuned us to direct pointing, but those devices have the display and touch-sensor aligned. When you are using the display and touch disjointed, it feels a bit odd, but not bad.  Thanks all for your comments.


I have tried the answers in this question     I have all ready installed the Update kb3102810, Installing and searching for updates is slow and high CPU usage occurs in Windows 7 and Windows Server 2008 R2  I have waited about 45 minutes and it has gone no where.  WindowsUpdate.log latest lines in file.   2016-02-11  17:36:23:677     356    1374    DnldMgr ***********  DnldMgr: New download job [UpdateId = {CB2E949C-7B90-4826-9DB0-0E5FA8B3651A}.201]  *********** 2016-02-11  17:36:23:677     356    1374    DnldMgr   * Queueing update for download handler request generation. 2016-02-11  17:36:23:677     356    1374    DnldMgr Generating download request for update {CB2E949C-7B90-4826-9DB0-0E5FA8B3651A}.201 2016-02-11  17:36:23:724     356    1374    Handler Generating request for CBS update CB2E949C-7B90-4826-9DB0-0E5FA8B3651A in sandbox C:\windows\SoftwareDistribution\Download\902a68569cfad0482255ed6e0f029c53 2016-02-11  17:36:23:724     356    1374    Handler Selected payload type is ptExpress 2016-02-11  17:36:23:740     356    1374    Handler Detected download state is dsHaveDownloadResponses 2016-02-11  17:36:24:052     356    1374    Handler Request generation for CBS update complete with hr=0x0 and pfResetSandbox=0  2016-02-11  17:36:24:114     356    1374    DnldMgr ***********  DnldMgr: New download job [UpdateId = {CB2E949C-7B90-4826-9DB0-0E5FA8B3651A}.201]  *********** 2016-02-11  17:36:24:114     356    1374    DnldMgr   * All files for update were already downloaded and are valid. 2016-02-11  17:36:24:130     356    1368    DnldMgr BITS job {14558046-1C04-40F1-9F69-5F5ED05C967E} completed successfully 2016-02-11  17:36:24:301     356    1368    DnldMgr   Download job bytes total = 431847, bytes transferred = 77616 2016-02-11  17:36:24:301     356    1368    DnldMgr ***********  DnldMgr: New download job [UpdateId = {FF010B0B-353D-4561-BDF7-59A5D6E56D3A}.201]  *********** 2016-02-11  17:36:24:301     356    1368    DnldMgr   * Queueing update for download handler request generation. 2016-02-11  17:36:24:301     356    1368    DnldMgr Generating download request for update {FF010B0B-353D-4561-BDF7-59A5D6E56D3A}.201 2016-02-11  17:36:24:442     356    1368    Handler Generating request for CBS update FF010B0B-353D-4561-BDF7-59A5D6E56D3A in sandbox C:\windows\SoftwareDistribution\Download\7c8467ad7aaf7387919d0296e8dfd0dc 2016-02-11  17:36:24:442     356    1368    Handler Selected payload type is ptExpress 2016-02-11  17:36:24:457     356    1368    Handler Detected download state is dsHaveDownloadResponses 2016-02-11  17:36:24:816     356    1368    Handler Request generation for CBS update complete with hr=0x0 and pfResetSandbox=0  2016-02-11  17:36:24:910     356    1368    DnldMgr ***********  DnldMgr: New download job [UpdateId = {FF010B0B-353D-4561-BDF7-59A5D6E56D3A}.201]  *********** 2016-02-11  17:36:24:910     356    1368    DnldMgr   * All files for update were already downloaded and are valid.   Task Manager Process List.

I installed Windows 7 fresh and installed SP1. Now, when I try to check manually for Windows Updates it just hangs on the Checking for updates screen.    I tried running the tools in , but this did not fix the issue either:  No matter what I do it just hangs on the "Checking for updates..." screen and goes no further.


I am a US Citizen planning on traveling to Germany to visit some relatives in the military.  I don't know what documents I need to have, and the last thing I want to do is show up at the airport (or worse, get to the other country) and find out I forgot something.  So what documents do I need to travel from the US?

I'm a US passport holder. What documents do I need when I fly from the U.S. to Germany?  Assume I'm going for a few weeks of vacation.  Obviously I need my passport.  What about a "visa"?  Anything else?


Sometimes I see a question that is clearly and indisputably off-topic (wether it's opinion-based or too broad etc.), and I vote to close the question for the appropriate reason. However, just because it's off-topic doesn't automatically mean it's a bad question. Every now and again I come across a very a good question that just happens to not be a good fit for SO, and sometimes I have in mind a good answer that I believe could truly help the OP.   My question is: is it bad to answer these questions, knowing they are indeed off-topic? I am perfectly aware that the question will likely be later closed/removed, but the OP will still likely benefit from the answer. I personally see no harm in answering these questions.

Should I post an answer to an off-topic question after flagging it?   I seem to find off-topic questions that I can give a good, useful and correct answer to. (The specific question tonight is , but it's happened several times this month now). Other users have clearly deemed the question worth a response; I think I can provide a better response based on the original question and the provided comments, but I also don't think the question fits well on StackOverflow.   By answering, I feel like I would validate the question's existence on SO. On the other hand, other users clearly deem the question appropriate enough to warrant answers.   What's the consensus for this situation?


Are there best practices for validating, recording AND formatting phone numbers?  Thanks for the link to AN answer regarding AN ELEMENT of my question: a regex for validating.  But please recognize that it does not answer the question that was asked.  There are no doubt countless suggestions for validating, recording and formatting phone numbers; many of which are highly rated.  However, since this is a common area that a multitude of developers have wrestled with for a long period of time, I asked if there are generally accepted best practices for the whole package.    Please read and respond to the stated question:  Are there best practices for validating, recording and formatting phone numbers?     Starting with the data element, are phone numbers better stored as integers or strings (or something else)? Next, should delimiters be stored with the numbers or stripped out? (In other words, should (212) 555-1212 be recorded as 2125551212 and  then formatted appropriately in a view?) Next, what's the best way to deal with formatting alternatives in different countries?  Perhaps if the country code was recorded in a separate field, a SWITCH statement could be used to select the right formatting for the view (or validation) of the phone number itself. Finally, are there good examples of regular expressions or other methods for validating phone number inputs?   I recognize the this is really a collection of questions, each of which likely has opinions scattered all over SO and the web.  Since validating, recording and displaying formatted phone numbers is such a common task, it seems like there should be some standard methodologies or best practices; and my question is, "Are there generally accepted practices, and where can I find them?"

I'm trying to put together a comprehensive regex to validate phone numbers. Ideally it would handle international formats, but it must handle US formats, including the following:   1-234-567-8901 1-234-567-8901 x1234 1-234-567-8901 ext1234 1 (234) 567-8901 1.234.567.8901 1/234/567/8901 12345678901   I'll answer with my current attempt, but I'm hoping somebody has something better and/or more elegant.


i am facing a problem from last 3 days on wards,     problem is in my menu item  list is not showing in Arabic but content inside website is showing in Arabic what will be the issue........please solve this  http://image-dent.com/arabic/index.php

I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1.  Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur?  This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2.


is explained very nicely in the link . But still i have not understood  Why is P value interpreted under null hypothesis?

Hypothesis testing seeks to reject a null hypothesis ($H_0$) on the basis of an assumption made about the sample following a certain distribution. This assumption is conditional on $H_0$ being true. So what is the flaw with the following reasoning?     If I reject $H_0$ in favor of the alternative hypothesis ($H_1$), I   must then assume that (1) $H_1$ is true, and (2) that at the   same time the variable under examination follows the distribution   used to reject $H_0$. Since we also stated that the assumed   distribution is conditional on $H_0$ being true, it appears that $H_0$   has got to be true in order to justify the assumption made about the   distribution. Logically, it would therefore seem that both $H_0$ and   $H_1$ have to be true, which is a paradox, because they are mutually   exclusive!


I was curious as to the correct uses of the words "whilst" and "while". In what context should I use them?

When should whilst be used instead of while?  For example, should I use the first or the second sentence?      They don't do this whilst they do that.   They don't do this while they do that.   Which would be correct?


How to convert a string to Boolean ?   I tried using the constructor Boolean("false"), but it's always true.

Can I convert a string representing a boolean value (e.g., 'true', 'false') into a intrinsic type in JavaScript?  I have a hidden form in HTML that is updated based upon a user's selection within a list. This form contains some fields which represent boolean values and are dynamically populated with an intrinsic boolean value. However, once this value is placed into the hidden input field it becomes a string.  The only way I could find to determine the field's boolean value, once it was converted into a string, was to depend upon the literal value of its string representation.  var myValue = document.myForm.IS_TRUE.value; var isTrueSet = myValue == 'true';   Is there a better way to accomplish this?


I have downloaded on my local machine eusflat 2019 template for paper  and using it in miktex following section in EUSFLAT2019_template.tex   \section{How Microsoft detects anomaly in azure} Microsoft uses a technology called security center \cite{microsf41} in its cloud environments.To detect threats and reduce false positives Security Center  collects data from Azure resources and network and then applies a lot of  machine learning and big data algorithms to detect threat.These techniques as more advance than normal signature based anomaly detection techniques.It is impossible to  manually identify the attack and predict the attack when it might happen.So the Microsoft \\ Security Centre uses following technologies     \newline   shows output in log as   Underfull \hbox (badness 10000) in paragraph   so I want to know why is this giving me message for badness in the template.


Let $ {a_k}$ be an unbounded,strictly increasing  sequence of  positive real numbers and $x_k=\dfrac{a_{k+1}-a_k}{a_{k+1}}$. Prove that $\sum_{k=m}^n x_k>1-\dfrac{a_m}{a_n}\forall n\geq m $ and $\sum_{k=1}^\infty x_k$ diverges to $+\infty.$  What I thought: $\sum_{k=m}^n x_k=\sum_{k=m}^n(1-\dfrac{a_k}{a_{k+1}})$  As $0<\dfrac{a_k}{a_{k+1}}<1$,taking $\dfrac{a_k}{a_{k+1}}=1-\dfrac{1}{k}$ for each $m\leq k \leq n$.  But i cant carry it more .Please help me.

Let $\{a_n\}$ be an unbounded, strictly increasing sequence of positive real numbers and let $x_k=\frac{a_{k+1}-a_{k}}{a_{k+1}}$. Which of the following statements is/are correct? (CSIR NET December 2014)         For all $n\geq m, \sum\limits^{n}_{k=m}x_k>1-\bf{\frac{a_m}{a_n}}$   There exist $n\geq m, \sum\limits^{n}_{k=m}x_k>\frac{1}{2}$      My attempt:  Analysing question in light of $a_k=k\implies x_k=\frac{k+1-k}{k+1}=\frac1{k+1}$, I feel both are correct, I doubt if  I can generalise the result in light of this one example.   Any way to prove that this true for general case?    Note: Please do not confuse  with my question. The first two options are different, I've marked the difference in bold.


Let $K$ be a field and $f(x)$ be a one-variable monic polynomial on $K$. Is the minimal polynomial on $K(f(x))$ of $x$ (with $t$ as a variable) $f(t) - f(x)$? I know that the minimal polynomial of $x$ I want to know is a divisor of $f(t)-f (x)$. I expect the minimal polynomial to be $f(t)-f(x)$. So, in general, is $f(t)-f(x)$ irreducible on $K(f(x))$?

Let $F$ be a field and $x$ transcendental over $F$. Let $y=f(x)/g(x)$ be a nonconstant rational function with relatively prime polynomials $f,g\in F[x]$. Prove $[F(x):F(y)]=\max(\deg f,\deg g)$.  My attempt: By replacing $y$ with $\frac{1}{y}$ if necessary we assume $\deg g\geq\deg f$. By the Euclid algorithm we assume $\deg g>\deg f$. Then $\deg g=\max(\deg f,\deg g)$, let $n=\deg g$. Let $R(t)$ be this polynomial $$R(t)=yg(t)-f(t)=\frac{f(x)}{g(x)}g(t)-f(t)$$ Then $\deg R=\deg g=n$ because $n=\deg g>\deg f$. The coefficients of $R(t)$ lie in $F(y)$ and hence $R(t)\in F(y)[t]$. Clearly $R(x)=0$.  Now I only have to prove $R(t)$ is actually the minimal polynomial of $x$ over $F(y)$. I believe the next step is to obtain a contradiction that $R(t)$ being reducible can lead to $f,g$ being not coprime, but I can't figure out how to do that.  P.S. A hint is preferred over a full answer.


Is there any difference in free-transforming a text or just adding the bigger font size??

Is there a difference between using Transform commands to scale text and altering the size of the font via Character panels?   I'm working in Photoshop CC


I've been recently learning about GLM's after learning about ordinary linear regression. In simple linear regression, I believe that an error term is used in order to account for randomness in the actual response when we predict values, like the equation below: Yi= β0+ βxi+ ϵi Where ϵi follows a normal distribution with expectation 0 and variance sigma^2. However I believe that this assumes that our Y variable follows a normal distribution. I was wondering what would be the equivalent error term (if any) for GLM's that we model assuming Y follows another distribution (such as Poisson or Gamma), and if it relates anyway to the "link" function used in GLMS. Thanks!

I have been discussing with several lab members about this one, and we have gone to several sources but still don't quite have the answer:  When we say a GLM has a family of poisson let's say are we talking about the distribution of the residuals or the response variable?  Points of contention   Reading  article it states that the assumptions of the GLM are The statistical independence of observations, the correct specification of the link and variance function (which makes me think about the residuals, not the response variable), the correct scale of measurement for response variable and lack of undue influence of single points  question has two answers with two points each, the one that appears first talks about the residuals, and the second one about the response variable, which is it? In this , when talking about assumptions, they state "The distribution of the residuals can be other, eg, binomial" At the beginning of  chapter they say that the structure of the errors has to be Poisson, but the residuals will surely have positive and negative values, how can that be Poisson?  question, which often is cited in questions such as this one to make them duplicated does not have an accepted answer  question the answers talk about response and not residuals In  course description from the University of Pensilvania they talk about the response variable in the assumptions, not  the residuals


"I always excelled at database and literature mining". "I always excelled at database- and literature mining". "I always excelled at database- and literature-mining".   What's the preferred version? In #1 "database" is too detached and may be interpreted as standalone. But since no hyphen is required between "literature" and "mining", it seems incongruous to put one after "database". What do you think?

My example in this case is "activity- and experience verbs", in the meaning "activity verbs and experience verbs". Does the hyphen suggest that "activity-verb" or "activityverb" is the uncontracted phrase, or is it correct to use a hyphen like shown in this case?


If there's n different coupons. Instead of ordering coupons one-by-one until you collect all n coupons as in the traditional 'Coupon Collector Problem', what if the coupons came in packs of m coupons. (given that the coupons are placed in the pack at random from the n coupons and are independent of each other). If random variable X is the total number of distinct coupons that one receives.   What is the expected value $E(X)$? (by using indicator random variables)  So given that one has already collected i coupons I was able to calculate the expected value of orders required to receive a new distinct coupon is $E(X_i)=\frac{n}{n-i}$ (according to the traditional 'Coupon Collector's Problem'). So now since the coupons are coming in packs of m, its pretty much the same as having m individual orders. And so I was thinking that the expected value of distinct coupons now is:  $E(X)=\frac{m}{E(X_i)}$ ?

I am trying to solve a variation on the .  In this scenario, someone is selecting coupons at random with replacement from n different possible coupons. However, the person is not selecting coupons one at a time, but instead, in batches.  Here's an example problem formulation: There are 100 distinct coupons. A person makes selections in 10-coupon batches at random (each coupon with replacement). What is the expected number of batches necessary to have selected 80 unique coupons?  I have been able to determine the expected number of selections necessary to have selected k unique coupons when selecting one at a time (much like Henry's ), but I'm a bit stumped as to how to go about solving it with this particular wrinkle.  Any tips/guidance would be greatly appreciated.


I have two videos. One is a normal video, the other is a grayscale video. Supposedly, merging the videos I can have a video with a depth of field blur effect. I wish to know how I could do it using ffmpeg. The videos are generated with WolfCamQL, is a program to capture Quake Live demos.

I'm trying to blur a portion of a video using FFmpeg (specifically to blur a face).  I have been trying to use a combination of timeline editing and the various bluring filters, but I cannot find a way to blur only a section of the video.  I'm hoping for something like:  -vf boxblur=enable='between(t,10,100)':width=20:height=20:x=400:y=200   Where width/height is size of blurred box and x/y are location of blurred box.  Is something like this possible?


The title pretty much covers it all, but I want to create a USB drive with Ubuntu on it to boot a Macbook Air. My computer has Ubuntu 14.04 on it, and that's it. How do I do it ?

How do I make an Bootable Ubuntu USB containing the the latest version of Ubuntu?  For completeness, how would I be able to do this on Ubuntu, Windows, OS X or another Linux distro?


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

I have the ISO image file (that is, *.iso) and I am trying to boot my  installation with this image. Is it possible? I know how to mount my ISO image to my filesystem (on my host machine), but I don't think VirtualBox boots an OS from a location on my file system.  I've even tried to mimic mounting, such that VirtualBox thinks it has to boot from the CD drive, but this failed.   What is the correct way to boot an OS from an ISO image in VirtualBox?  My host machine is Ubuntu 10.04 (Lucid Lynx) and my VirtualBox version is 4.1.4.


Is there an explanation of why the clone troopers changed to storm troopers? And why the clone troopers seemed to be more organized and specialized (colors, weapons variations, etc) than Storm troopers?

I understand why the Empire would want to start using more than one genetic template to create clone troopers, but why did it start using non-clone troopers instead of just continuing the cloning program?  It seems that with cloning they were able to use a training program (and genetic manipulation) that gave them completely loyalty (other than when the Kaminoan rebellion, where the Kaminoans had sabotaged the training programs).  Why stop using such troops and start using people that might question orders or aren't as easily controlled as clones were?


If I bookmark a question posted by userA, will I receive, in the future notifications of userA's new posts?

Is there a way to follow the questions and answers posted by a developer on Stack Overflow?


I can't make my string entireFileText test to see if it is the same as Email.  I think I'm missing something...  if(entireFileText == Email) {                         JOptionPane.showMessageDialog(frame, "Welcome back!", "Confirmation", JOptionPane.INFORMATION_MESSAGE);                         }else{                             System.out.println("oops");                         }

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


I accidentally forced my PC to shutdown by holding onto the power button during a BSOD in windows 10 and ever since, my PC has not been able to boot to the login screen instead it keeps giving the "Inaccessible Boot Device" error. I have tried all the recovery options but none of which seems to work.  PS I also have Kali Linux installed (and working currently) on the same hard drive.  How exactly can i make my PC boot without loosing any of my files

I have a Windows 10 computer. This morning it restarted into a blue screen with error code Inaccessible boot device.  There are no recent hardware changes. Also I think it was not after a Windows update installation. At least I chose Restart to restart, and not Update and restart as usual before an update installation.  According to other posts related to this problem I tried the following:   Restart into save mode: no success, the same error displays Restart into recovery console: The system partition usually mounted as C: is available as D:   chkdsk d: /x completes without finding any error. I conclude, that the problem is not related to a hard disk failure. bootrec /fixboot completes with success.  bootrec /scanos completes with a message Number of Windows installations identified : 0. Why doesn't it find the Windows installation, even though it is available under D:\ ? sfc /verifyonly has found integrity violations, but sfc /scannow finished with the message The Windows resource protection was not able to complete the operation.  System restore to a previous restore point: After a (long) while, the task completed, but without solving the problem. Booting from the Windows Installation disk:   I tried the option Repair Windows: It was not possible to roll back to a previous restore point Update Windows keeping programs and files seems to work only when booting first into the current installation to do an upgrade. It cannot be done while booting from the installation disk (as it was the case in previous versions of Windows).     Is there anything left I could do before reinstalling Windows 10 ?  Edit: Now there is the second computer with the same problem within 2 days. This smells like an epidemy (caused by a bad Windows update ?)  This time I tried:   Restart into save mode: no success, the same error displays System restore to a previous restore point : No success, it offers to try from another restore point.   I stopped here. I just don't want do make a mistake that forces me to reinstall it.


The story is about a rich man who makes clones of himself. The clones are fed and exercised so that they will have perfect bodies, but are not given the ability to mentally develop. They cannot speak or communicate with the world.  When the rich man gets old, he switches his brain into one of the clones. This way, he will give himself a new, fresh body. However, he is horrified to find that when he wakes up after the transplant, he is in the same body. He has transplanted his brain, but not his soul, or his memories. He tries to tell the operators that there has been a mistake, but he finds himself unable to get the words out. he realizes he will be trapped as an idiot forever, while the clone steals his life from him.

I'm looking for a short story whose title I can't remember.  In it a wealthy man practices cloning and consciousness transfer to achieve immortality, often parading older bodies around his estate naked (not a nice guy). The story follows a final transplant, which doesn't go as expected. The man is left trapped with his memories and no ability to speak, while the clone walks off behaving exactly as he would.


The problem about a frog climbing a stair of size N, in steps of size 1 or 2, can be formulated as Fibonacci; and if it can jump in steps of size $1,2,...k$ there must be $k$ recursive calls.  I want to know if its possible to solve this problem using combinations with repetition instead of using recursion?   Im trying to use combinations with repetition formula to give number of positive integer solutions to the restricted equation representing the problem (for example k=3 and N=4, the equation  $a+b+c+d = 4$ with $1 \le a,b,c,d \le  k$ ) and after that subtracting the impossible solutions (i.e. solutions wich contain value of zero for one or more variables), but I'm having trouble restricting the equation and counting the impossible solutions.  Wonder if Im walking in the right direction here?

I think there are $\binom{b+ c - 1}{c-1}$ ways to distribute $b$ balls in $c$ containers. (Please correct me if that's a mistake.) How does this change if I am not allowed to place more than $n$ balls in any given container?  If we call this number $N(b,c,n)$ then I can come up with  $$N(b,c,n) = \sum_{k=0}^n N(b-k, c-1, n)$$  with the base cases  $$N(b,c,n) = \binom{b+ c - 1}{c-1}$$  for $n\geq b$, and  $$N(b,c,n) = 0$$  for $n<b/c$.  Is there some better way of writing this than that recursion relation?


I found the quote  The introduction of numbers as coordinates is an act of violence.  from  from  is very interesting. Unfortunately, I can not understand it. I asked for elaboration below that answer and have not received any response for a long time. Could you please elaborate on this quote? Thank you so much!

"The introduction of numbers as coordinates is an act of violence." - Hermann Weyl.  A lot of people like this quote, apparently. They also seem to associate it to the manifold context in the obvious way: they interpret the quote as saying that focusing on coordinate charts is insightless, or at least dry. Although I aggree with this, I feel like the way the quote is phrased is not inclined to that interpretation. If not by the fact that Weyl is connected to geometry (and that this quote is in Bredon), I would interpret this phrase as saying that "Representing numbers by a given basis is insightless and can lead to mistakes, like thinking that divisibility is dependent of the number basis you are using." I think the words numbers and coordinates are strangely placed.  Therefore, my question is: What was the precise context on which this quote arose and, if possible, can we pinpoint exactly what did Weyl mean?


I use the IEEEtran to edit the papers, but the journal name won't show in the reference, only like " [1] F. Basile, F. Caccavale, P. Chiacchio, J. Coppola, and C. Curatella,“Task-oriented motion planning for multi-arm robotic systems,” vol. 28,no. 5, pp. 569–582." How can I solve this?  thank you very much.

I use "ieeetran" and the following code to generate the reference (without URL information)  \bibliographystyle{IEEEtran} \bibliography{IEEEfull,paper01Const}   however, the result is  "Y. Qian, “Design and Control of a Personal Assistant Robot,” Ph.D. dissertation."  And the generated .bib files is   @phdthesis{qian_design_2013,   location = {{France}},   title = {Design and {{Control}} of a {{Personal Assistant Robot}}},   url = {https://tel.archives-ouvertes.fr/tel-00864692/document},   abstract = {The purpose of this thesis is to design, model and control of a personal assistant robot used for domestic tasks. In order to make the robot's design more efficient, a virtual simulation system is built using dynamic simulation software. ...},   pagetotal = {214},   timestamp = {2017-07-06T15:44:04Z},   langid = {english},   institution = {{Ecole Centrale de Lille}},   author = {Qian, Yang},   urldate = {2016-02-25},   date = {2013-07-04},   file = {Full Text PDF:C\:\\Users\\Yan WEI\\AppData\\Roaming\\Zotero\\Zotero\\Profiles\\jf7ifsnc.default\\zotero\\storage\\35UHZBC4\\Qian - 2013 - Design and Control of a Personal Assistant Robot.pdf:application/pdf} }   Wherever, the complete reference is   "Yang Qian. Design and Control of a Personal Assistant Robot. Other. Ecole Centrale de Lille, 2013. English."  How can I solve this problem? Thank you very much.


If photon has energy, it has gravity.  If photon has gravity and move through space at light speed, it creates gravitational shock wave (like sonic boom because gravity move at the same speed as photon).  If photon creates gravitational shock wave, it looses energy.  If photon looses energy, so it decays.  Which sentence is wrong ? I don't think all of these will be true because if these are true, they will prove that photon have to decay which we still can't prove. But I have no idea which one is wrong.

As explained in the answers to  post, photons apparently exert a gravitational pull on other objects. It has also been explained on this site, that gravity propagates at the speed of light.  I'm wondering, though, how do you reconcile these two facts? I'm trying to imagine the gravitational field made by a photon and it seems like there are some paradoxes. For example, how can gravity propagate ahead of the photon at the speed of light, if the photon is also travelling at the speed of light? My guess is the solution is probably found in relativity, but I certainly can't figure it out.   Right now, the best I can do is to think about gravity as sound, and a photon as an object travelling at the speed of sound. Can anyone help me out?


newbie here!!! so guys I’m running Ubuntu 14.04 and everything was perfect before i begun to get stuck while using it, several times, the systems just stop and nothing is working!every time i need to press the power off button to shutdown the systems and power it on again, and I’m losing a lot of things can any one tell me what to do??? thanks in advance when it stuck it looks like this:

All operating systems freeze sometimes, and Ubuntu is no exception. What should I do to regain control when...   just one program stops responding? nothing at all responds to mouse clicks or key presses? the mouse stops moving entirely? I have an    In what order should I try various solutions before deciding to pull the power plug?  What should I do when starting up Ubuntu fails?  Is there a diagnostic procedure I can follow?


I have an un-patched 32-bit PC (no microcode is available) running Ubuntu 16.04.  If I will use just the guest account (not the administrator account) for browsing, would it be possible to steal the WiFi password?  Would it be possible to steal the administrator password of the PC?

I was wondering if I use my computer running Ubuntu only for browsing while using the guest account on an unpatched PC logging in to any site I browse - will it be possible to steal any passwords typed into the browser or not?   Can e.g. a harmful web site steal my administrator password for the PC or even the WiFi password?


When I try to put in my code snippets it never works. If I press space 4 times, it only monotypes the first line after I paste in my code. No freaking way are we supposed to go in and put 4 spaces on ever line??

How do I post text so that it is formatted as code?  What do I need to do so that my code shows up properly — not escaped or removed — when posted? And how to get the correct syntax highlighting?     For more information, see "" in the .


I am using System.Runtime.Caching to persist variables in cache, but later i cannot access to them because are disposed and the program throws a ObjectDisposedException with the message: DbContext has been disposed I didn't execute Object.Dispose(), so the class ObjectCacheare disposing it in background. In what moment at what moment does it happen? after doing cache.add? It can be avoided? How i made it: Making the list: using (GesBrokerSuiteEntities ctx = new GesBrokerSuiteEntities())                 {                                         rel_tareas_orquestador nuevoregistroOrquestador = new rel_tareas_orquestador();                      nuevoregistroOrquestador.id_robot_hija = idProyindividual;                     nuevoregistroOrquestador.id_robot_padre = 2;                     nuevoregistroOrquestador.id_robot_tarea_padre = "2";                     nuevoregistroOrquestador.id_robot_tarea_hija = idProyindividual - 1+"";                     nuevoregistroOrquestador.id_tarea_hija = Int32.Parse(id2);                     nuevoregistroOrquestador.id_tarea_padre = 2;                     nuevoregistroOrquestador.sincronizada = 2;                     nuevoregistroOrquestador.esperar_padre_completa = 2;                      ctx.rel_tareas_orquestador.Add(nuevoregistroOrquestador);                     listaRelTareasOrquestador.Add(ctx);  1-Adding the list to cache CacheItemPolicy cacheItemPolicy = new CacheItemPolicy(); cacheItemPolicy.AbsoluteExpiration = DateTime.Now.AddHours(1.0);                      cache.Add("listaOrquestador", listObject, cacheItemPolicy);  2-Then i get it in another method listaRelTareasOrquestador = (List<GesBrokerSuiteEntities>)cache.Get("listaOrquestador");  After this, i cannot access to the content of the list because it disposed. UPDATE: withing the using() works, the elements aren't disposed. now the problem us this, when trying to get the saved values, it obtains the database rows: nuevoregistroOrquestador.id_robot_hija = listaRelTareasOrquestador[0].rel_tareas_orquestador.FirstOrDefault().id_robot_hija;  I know it is executing a query in my DB, any way to obtain the data i saved previously? Like a local variable. UPDATE 2 Now when i'm trying to access the values into the list,i am not receving the previous ones: rel_tareas_orquestador nuevoregistroOrquestador = new rel_tareas_orquestador();  nuevoregistroOrquestador.id_robot_hija = listaRelTareasOrquestador[0].rel_tareas_orquestador.FirstOrDefault().id_robot_hija; nuevoregistroOrquestador.id_robot_padre = registro.rel_tareas_orquestador.FirstOrDefault().id_robot_padre; nuevoregistroOrquestador.id_robot_tarea_padre = registro.rel_tareas_orquestador.FirstOrDefault().id_robot_tarea_padre; nuevoregistroOrquestador.id_robot_tarea_hija = registro.rel_tareas_orquestador.FirstOrDefault().id_robot_tarea_hija;  I know the methods are returning database values due to querys, how i can access to the list values i saved previously? Visual Studio shows me that in debugging:

What is the purpose of the Using block in C#? How is it different from a local variable?


I have a working code (below) to convert a number to Excel-like (A...Z AA...AZ BA...BZ ...ZA-ZZ) column codes (headers).  For simplicity I limited it to 1 or 2 character codes.  Can the algorithm be streamlined by using a bit more of elementary math or using it differently?  Please note that I just happened to need it in JavaScript (so I wrote it in JS) and am not looking for pure code improvements.  function numberToLetters(nNum) {     var result;     if (nNum <= 26) {         result = letter(nNum);     } else {         var modulo = nNum % 26;         var quotient = Math.floor(nNum / 26);         if (modulo === 0) {             result = letter(quotient - 1) + letter(26);         } else {             result = letter(quotient) + letter(modulo);         }     }      return result; }  function letter(nNum) {     var a = "A".charCodeAt(0);     return String.fromCharCode(a + nNum - 1); }

I want to implement numbering scheme like Microsoft Word uses for numbering.  first one gets = A,next is  B, next is C, .... then AA, then AB,....and so on.  as shown below   A        B  C  .   .  AA  AB  AC  .  .  AAA  AAB  ....   '=>' here means converted to.  some examples:       1 => A 26 => Z 27 => AA 52 => AZ 53 => BA   and heres the code for it:     var convertToNumberingScheme = function(n){         var x = n-1,             r26 = x.toString(26),             baseCharCode = "A".charCodeAt(0);          var arr = r26.split(''),             len = arr.length;          var newArr =arr.map(function(val,i){             val = parseInt(val,26);              if( (i === 0) && ( len > 1)){                 val = val-1;             }              return String.fromCharCode(baseCharCode + val);         });         return newArr.join('');     }   It seems to work fine, but any ideas if there are some potential bugs or ways to  optimize this.


I am preparing a simple presentation and would like to select some of the references in my bibtex file. I tried to do it as I do in a .tex file but it gave me '?'.  I am using the package bib at the beginning as   \usepackage{natbib}   I am doing the citations at the body of my slides such as \citep{xxx}   Then at the end, I add the commands  \begin{frame}{References} \bibliography{mybib} \bibliographystyle{agsm} \end{frame}   Do you have any idea why it does not work?

I've browsed the forums and found a number of posts that have addressed this issue, but none of the solutions seem to work for me. I have the following script that I just copied from the bibtex home page to get familiar with it. Instead of the citation number I get a question mark. I compile using Latex+Bibtex+Latex+Latex+PDFLatex+ViewPDF just as has been previously suggested and the problem persists.   \documentclass[11pt]{article} \usepackage{cite}  \begin{document}  \title{My Article} \author{Nobody Jr.} \date{Today} \maketitle  Blablabla said Nobody ~\cite{Nobody06}.  \bibliography{mybib} \bibliographystyle{plain} \end{document}   My bibliography (Bib.bbl)  @misc{ Nobody06, author = "Nobody Jr", title = "My Article", year = "2006" }    Looking at previous posts one thing that is concerning is that my .bbl looks empty as shown below. Further, I don't have a .blg  \begin{thebibliography}{}  \end{thebibliography}


I have looked all over the settings for a way to change the sound theme, but I can't find one. There is one spot in the settings where you can choose an alert sound, but that doesn't look like it would be what I want and it only gives the option of default. I have the Unity Tweak Tool,but there are no sound options present there. I downloaded a theme and placed the theme folder in /usr/share/sounds, but I don't know where to choose the theme.  This is for Ubuntu 16.04 and not a duplicate but its very similar.

I'm trying to set up individual system sounds for ubuntu 15.04. I've read some instructions but they're a bit pithy for me.  Is there an app to add?


I am teaching a university maths module, which is currently taken by approximately 300 undergraduates. By the way, I am teaching in Asia.  Due to the number of undergraduates, tutorial classes are conducted from Monday to Thursday. There comes the problem:  This course consists of 2 in-tutorial quizzes. The quizzes are set very similarly so that the level of difficulty is consistent. However, due to the similarity of question, students from Tuesday, Wednesday and Thursday classes can obtain quiz questions and keep practising them. In the end, these students excel while students from Monday do averagely or poorly.   Question: How to deal with this kind of situation? A few solution that I can come out with is to have a mid-term, where everyone sits in a lecture hall.   Another way is to set different questions each day. However, this method does not guarantee the level of difficulty is consistent throughout all tutorial classes.  The last way, which I don't prefer, is to set assignment. However, students tend to copy each other and t defeats the purpose of assignment.

I teach a writing course to different sections, across different days of the week. From the schedule, some students will take their mid-term exam early in the week, while others will take it later in the week. Recently, I found one student who was “just checking to see what the exam was like”, but was planning to go to another session to actually take the test. I realized there might be a variety of ways that students taking the exams on Friday would have an advantage over those taking it on a Monday.  I've taken the following steps in an attempt to address this problem:   I build multiple tests, e.g. "A", "B", "C", etc., which are of similar difficulty, have the same types of problems, but different subjects. "A" is given to one section, "B" to another, etc. Provided a sample test that students can print and practice with and discuss with me in class.   Note that, there are several challenges to administering this:   The classes are large, and the school offers me no assistance in managing the exams. Many students regularly attend my lectures during sections that they did not register for, so I will not easily recognize who belongs in which time.   Are there any additional steps I should consider to make sure the test is administered fairly?


What is the limit of the sequence: $$\frac{1^1+2^2+3^3+\dots +n^n}{ n^n}$$  I tried only to break it in $(1/n^n)+..+(n^n)/n^n$ and say that the first equals to zero and the last is $1$. I have no idea what to do with the rest. Any ideas?

$$\lim_{n \to \infty}{\frac{1^1+2^2+3^3+\cdots+n^n}{n^n}}.$$  With a first look this must give $1$ as a result but have a problem to explain it.  How can I do it?  Edit  I noticed that it is $\frac{\infty}{\infty}$.  $$\lim_{n \to \infty}{n^{n}\frac{(\frac{1^1}{n^{n}}+\frac{2^2}{n^{n}}+\frac{3^3}{n^{n}}+\cdots+1)}{n^n}}= \lim_{n \to \infty}{\frac{1^1}{n^{n}}+\frac{2^2}{n^{n}}+\frac{3^3}{n^{n}}+\cdots+1}=1$$  Is this correct?


I would like to Change a HTML class with JavaScript  HTML  <i id="test" class="fa">   How can I do it really simple?

How can I change the class of an HTML element in response to an onclick or any other events using JavaScript?


I want to compare dates and not display the same information twice. i.e. if I have been somewhere from 5/2/19 - 14/2/19 I want to display: "From 5th - 14th February 2019" rather than the long version, but if over the month (or year) it will need to display all. (I need to write these letters often, so automated the document)  \documentclass[a4paper,12p]{article}  \newcommand{\hospital} {London Hospital } \newcommand{\system} {Robot 5} \newcommand{\periodstart} {\newdate{date}{05}{02}{2019}} \newcommand{\periodend} {\newdate{date}{14}{02}{2019}}  \usepackage{datetime} \newdateformat{normal}{%   \longdate \ordinaldate{\THEDAY} \monthname[\THEMONTH] \THEYEAR}  \begin{document}    \null\hfill \normal \today \\      \bigbreak     {\bfseries\large \hospital \par} {\bfseries\large \system \par} {\bfseries\large Trial period: {\periodstart \normal \displaydate{date}} -- \periodend \normal \displaydate{date} \par}  \end{document}

I would like to use the  package to format date(time) ranges.  For example, \DTMdaterange{2017-08-05}{2017-09-10} would output 2017-08-05/09-10 in ISO format, or something like August 5 to September 10, 2017 in US English.  I looked into implementing it myself, but find it a bit hard.  Is there any package that already includes this functionality aside from ?  I thought  might be a good candidate, but cannot find anything useful (I am mostly interested in formatting dates; times are not necessary).


Max value of $$\int_{a-1}^{a+1} \frac{1}{1+ x^8} \,dx$$is attained at what value of a?   My attempt:  Let the given integral be $\alpha$ . Then the max value can be calculated by differentiating the term. So for differentiating, i used the Newton-Leibniz rule but all i could infer from the result was that the function $\alpha$ is monotonous. I don't know what else to do. Any inputs will be appreciated.

I am not being able to understand the graphical method of solving this, any simple explanation will be appreciated.  A non-graphical calculation will be very helpful too.  Thank you so much in advance!


Given the following string:  Test <- c("123 - Test1", "1234 - Test2", "123 - 45 - Test3")   When I use gsub as below with very basic regex  gsub(".*- ", "", Test)   I get the following output:  "Test1" "Test2" "Test3"   How can I change my regex to only substitute up until the first - to get the following result:  "Test1" "Test2" "45 - Test3"   I know regex is 'greedy' so I am looking for a way to overcome this greediness.

I have this gigantic ugly string: J0000000: Transaction A0001401 started on 8/22/2008 9:49:29 AM J0000010: Project name: E:\foo.pf J0000011: Job name: MBiek Direct Mail Test J0000020: Document 1 - Completed successfully  I'm trying to extract pieces from it using regex. In this case, I want to grab everything after Project Name up to the part where it says J0000011: (the 11 is going to be a different number every time). Here's the regex I've been playing with: Project name:\s+(.*)\s+J[0-9]{7}:  The problem is that it doesn't stop until it hits the J0000020: at the end. How do I make the regex stop at the first occurrence of J[0-9]{7}?


I want to got difference between 2 date in Years ,Month , Days for   Example : Hirring Date : 25/7/1998 CurrentDate : 30/9/2017  The resulte to be like :  19 Years – 2 Month – 11 Days

What would be the best way to calculate someone's age in years, months, and days in T-SQL (SQL Server 2000)?  The datediff function doesn't handle year boundaries well, plus getting the months and days separate will be a bear.  I know I can do it on the client side relatively easily, but I'd like to have it done in my .


How do I change the settings to where I can press the space bar and it put a space after the letter instead of deleting the letters after it. For example, when I have a sentence like " I hav to go." And I want to put the cursor after the v to add an e it will end up like this "I haveto go" then I go to put a space between them and it does this " I haveo go" then add another space " I have go" then "I havego" then another space and it does the same thing " I haveo" and it deletes the letters after it.

We all use editing facilities to change a line of text as we are entering it. There are two principal editing modes within a line, a) "insert mode" which inserts non-editing characters at the point of the cursor, and shuffles text to the right, and b) "overwrite mode", in which non-editing characters simply overwrite whatever character the cursor selects.  Overwrite mode IMHO is left from the days of green-screen CRTs. The only use I have ever found for it is drawing 2-D pictures in ASCII, which I quit doing back in the 80s when real drawing tools became available.  Windows (stupidly IMHO) offers overwrite mode toggle-enabled by use of the INSERT key on the keyboard. (I'd guess Linux/Unix likely follow suit in the usual Windows-envy). I don't ever hit that button because it just puts me in overwrite mode.  However, as I'm typing sometimes Overwrite mode suddenly happens. I think it must be some strange combination of ALT/Windows/CTRL/SHIFT and some other key, or two standard keys depressed in time nearby. Does anybody know what the alternate key sequence is so I can try harder to avoid it? Is there a way to tell Windows to simply stop using Overwrite mode?


Is it possible to apply formatting to all tables in a single document without doing it one by one?

I have a bunch of large documents, with many tables that have different and inconsistent fill styles - some of them are not readable in black and white when printed.   I cannot change the background fill for all the tables at once. The problem I have is that when I open such a document, and Select All, the Table Properties are inactive.  Do you know a technique for selecting all the tables, or a method for applying global format of tables, with a script or some other way?


for (int i = 0; i< expArray.length; i++){             System.out.println(expArray[i]);             if ( expArray[i] == "5" ){  ///WHY IS THIS NOT WORKING!!!??                              System.out.println("here");   I know the output of the System.out...:  0 = 0 + 5   This is how my String array was made:      for (int i = 0; i< expArray.length; i++){         if(varTable.get(expArray[i]) != null){             expArray[i] =  Integer.toString((int) varTable.get(expArray[i]));         }     }   So the issue is, at the expArray[i] == "5" ) if block up top its not going in at i=1 where it should. any reason/thoughts?

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


The piece that I remember from this book or maybe even a series is that it's about a brother and sister - who were in their teens I feel - with either magical abilities or find a book with magical information in it.    I remember the girl always having like a zipper floating next to her in space that she could store things in. They traveled all around together.    In one book or chapter I remember they were both whales in the ocean and had to get used to the fact of going up for air, it discussed the phosphorescent fish down there etc.  I have been after this for a decade and just keep striking out. I would love to re read the series. I feel like I read this around/before the Artemis Foul books.

I can't remember the gender of the main character.  I remember bits and pieces from different books, but I think they're all part of the same series. The pieces may not be in order or from multiple books.   Boy somehow ends up in a mirror universe that's darker and seems to have no people. He has to travel to a certain office(?) building and steal a book. I think this is towards the end of the book (I can't remember the events leading up to it). I think he finds the portal in a forest or something behind his school. He goes into the ocean with mermaids or something and has to save the ocean from pollution. Aliens exist and are observing Earth, because they think it's undeveloped and are waiting for them to be advanced enough. His mother ends up in hospital and he does something to save her. He goes to Ireland(?) and enters a mountain or something to find a race of people. I can't remember who showed him how, but I'm pretty sure she used magic. He goes to Mars and saves a race from war with themselves(?). This place was hidden inside an illusion. He's also grouped with a linguist that learned their language. He travels to another world where there's a prince. I can't remember, but I think it might've been part of a tournament. His sister goes to a robot planet through a portal. I think the actual planet was a robot/AI and had lots of little robots on it. Can't remember what happens here, but he goes there and saves her from something.   It was set a few years ago, when computers weren't common (his family got one early in the first book, I think).  Thanks in advance if someone finds it.


I was trying to prove that $\tan \frac{x}{2}>\frac{x}{2}$ for all $x \in (0, \pi)$ I am trying to use some trigonometric identity that gives me lights to be able to prove this, could you give me some way?

In proof of $\displaystyle\lim_{x\rightarrow0}\frac{\sin{x}}{x}=1$ is assumed that $\sin{x}\leq{x}\leq\tan{x}$ while $0<x<\frac{\pi}{2}$. First comparison is clear, arc length must be greater than sine value, but how about $x\leq\tan{x}$, why tangent is longer than arc?


From my understanding. if the car is moving at the velocity of 10 m/s and the fly is moving at the velocity of 5 m/s. the fly must move backward at the velocity of 5 m/s. but the fly seem to be able to keep up with the car just fine.

A couple of weeks ago I was travelling in a car (120 km/h approximately) and I saw a  flying in front of me (inside the car, near my nose, windows closed). I wonder how was that possible.   Does it mean is really flying at 120 km/h or the fly is being affected by some kind of gravity/force?


I have recently bought Dell 7560 (7000) series. It has come with Windows 10. I want to add ubuntu as second operating system. If anyone has tried installing ubuntu with Windows 10 in the same system, can you please tell me what problems did you face and what should I keep in mind except taking backup of the system. Also, which version of ubuntu is supported? I know there are some many answers related to this but I need answers related to this Dell 7560 system. I would like to know compatibility issues, specifically.

I am a bit financially strapped and received a Gateway GT5056 tower. The tower has an AMD dual core 64-bit processor in it. Will Ubuntu 12.04 run on this machine? I will not have any other application other than LibreOffice installed.


Give a function $g : \mathbb{N} \times \mathbb{N} \to \mathbb{N}$  such that $g$ is one-to-one and onto function.  the onto part I could easily solve but every function I think of, is not one-to-one.

Show that $\mathbb{N} \times \mathbb{N} \sim\mathbb{N}$.  I found a bijection such that $g(k,l): \mathbb{N} \times \mathbb{N} \to \mathbb{N}$ by  $$g(k,l) = {(k+l)(k+l-1) \over 2} - (l-1)$$  But I am having trouble showing that it is 1-1 and onto.  First I said let   $${(k_1+l_1)(k_1+l_1-1) \over 2} = {(k_2+l_2)(k_2+l_2-1) \over 2}$$  and I was trying to use that to show $k_1 + l_1 = k_2 + l_2$ but I don't know how to do that, and once I get there I'm not sure how to show that $l_1=l_2$ or $k_1=k_2$  for onto I said let $y \in k+l$.  Then $${y(y-1) \over 2} = y$$ so therefore $g(k,l)$ is onto.  therefore g is a bijection.


I'm looking for a way to abort a script execution if a sql query returns some results. I've found a few solutions on the forum but all of them lead to shutting down QGIS (thing I precisely want to avoid). This question has already been discussed at  and the conclusion was that it was not possible yet. 7 years later, I'm wondering if this has eventually been made possible? My script: conn = psycopg2.connect(db_key)  cur = conn.cursor()  try:     cur.execute(""" --  SELECT * FROM a.table1 WHERE ps_code like 'test_erreur' """)  except:     print ("Can't run this SQL query")  rows = cur.fetchall()  if rows is None:      print("No error found") if len(rows) > 0:     iface.messageBar().pushMessage("Erreur", "Script processing had to be stopped because errors has been detected", level=Qgis.Critical, duration=30)     for row in rows:         print (row)     sys.exit()

I'm writing a Python script to use it in Processing framework. I need to cancel script execution if certain conditions are met (to save user's time). I tried to use sys.exit(arguments) command. The issue is that not only the script, but QGIS itself shuts down too. I also tried quit() but result is the same. How should I terminate script in Processing framework? The following code is for reproduction purpose only. I don't need ad hoc solution for this particular case because I already have it. I need to know how to deal with this issue in general. ##Raster processing=group ##raster_1=raster ##raster_2=raster   from osgeo import gdal import sys from numpy import * import ntpath import re import platform from PyQt4 import QtGui   raster_1 = gdal.Open(raster_1) raster_2 = gdal.Open(raster_2)  rasters_list = [raster_1, raster_2]  # create a message for the case when CRSs of rasters do not match class WrongCRS(QtGui.QMessageBox):    def __init__(self):     super(WrongCRS, self).__init__()      self.initUI()    def initUI(self):      self.warning(self, 'Oops!',             "Rasters must have the same CRS!\n\nExecution cancelled!", QtGui.QMessageBox.Ok)  # check CRS proj = None for raster in rasters_list:   new_proj = raster.GetProjection()   if proj is None:     proj = new_proj   else:     if proj != new_proj:       WrongCRS()       sys.exit('CRSs do not match!')     else:       continue


Find the least Positive Integer Satisfying $1+\frac{1}{2}+\frac{1}{3}+\cdots+\frac{1}{n} \ge 4$  My try:  I actually applied a Brute Force taking:  $$\int \frac{dx}{x} \ge 4$$ Then we get: $$\ln x \ge 4$$ Hence $$x \ge e^4$$  So approximately $n=55$  Is there any better approach?

Question: $ 1 + 1/2 + 1/3+\dots+ 1/n > 4.$   Find the range of smallest value of n.       Answer: $n$ lies in $(20,60)$.      Source: KVPY 2017.   To the best of my knowledge I find this series to be divergent and thus its sum can not be calculated. I couldn't think of a way to approximate value of $n$. Help is appreciated!