How do you evaluate:  $$\sum_{n=0}^\infty \frac{(-1)^n}{(2n+1)^3}$$  Not too sure where to start. I thought of trying to convert the denominator into some integral, but that didn't seem to work. According to Wolfram Alpha, the answer is $\frac{\pi^2}{32} $ but I'm not sure how. There's some use of a generalized zeta function on the Wolfram Alpha page, but I'm not too sure how to work with that. If someone would give me the answer using zeta functions, could you show step by step? I would really appreciate it. If there's an easier way, that would be appreciated!   Oh Also, please no Complex Analysis! Thanks in advanced!

Prove that : $$\sum_{k=0}^{\infty} \frac{(-1)^{k}}{(2k+1)^3}=\frac{\pi^3}{32}.$$    I think this is known (see ), I appreciate any hint or link for the solution (or the full solution).


I'm fairly new to python, so I need your help  I have to write a program that compiles email addresses out of a list of student names. I already got a working code to put them together and print them the right way. my only problem is, that i can't seem to match the first syllable of the name with regex (first syllable = from the first character up until the first time a consonant follows after a vowel)  this is what i tried:  first_mail = re.match(r'\w*[_aeiou][bcdfghjklmnpqrstvwyz]', first).group()  this expression will give me everything up until the last time a consonant follows after a vowel, but i want it to match only up until the first time  edit: Frederic should become fred, soeren should become soer

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

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 am trying to set global parameters to control items separation in enumerate and itemize environments. The command (from )  \xpatchcmd{\itemize}{\def\makelabel}{\setlength{\itemsep}{\heightItemSepI}\def\makelabel}{}{}   Works well to set the separation for itemize to a predefined height of \heightItemSepI  The command (from )  \makeatletter \patchcmd{\@listI}{\itemsep3\p@}{\itemsep=0.5em}{}{} % this sets the space globally (for itemize or enumerate) \makeatother   Works for both enumerate and itemize, but it cannot accept a predefined height and, if put there, it will throw the error 'missing number, treated as zero'.  My question is how to combine the good features of both approaches? I do not like to enter the numbers directly in commands because I like to set parameters outside the commands modifying packages/classes codes. This helps me set things up quickly when I come back after a while. Also, I use predefined lengths for certain calculations about the layout of my documents.  I know that enumitem allows for easy customization of these parameters but enumitem in beamer can lead to 'TeX Capacity Exceeded' errors  \documentclass[aspectratio=169]{beamer}  \usepackage{xpatch}  \newlength{\heightItemSepI} \setlength{\heightItemSepI}{0.3cm} \newlength{\heightItemSepII} \setlength{\heightItemSepII}{0.2cm} \newlength{\heightItemSepIII} \setlength{\heightItemSepIII}{0.15cm}  \makeatletter     \xpatchcmd{\itemize}{\def\makelabel}{\setlength{\itemsep}{\heightItemSepI}\def\makelabel}{}{}     \g@addto@macro\@listii{\itemsep \heightItemSepII}     \g@addto@macro\@listiii{\itemsep \heightItemSepIII} \makeatother  \makeatletter \patchcmd{\@listI}{\itemsep3\p@}{\itemsep=1em}{}{} % this sets the space globally (for itemize or enumerate) \makeatother   \usepackage{blindtext}   \begin{document}  \begin{frame}      \blindlistlist[1]{enumerate}  \end{frame}  \begin{frame}      \blindlistlist[1]{itemize}  \end{frame}  \begin{frame}[allowframebreaks=0.9]{Long Lists}      You can insert a very long nested list by using a page-wide frame with multicols      \blindlistlist[3]{enumerate}  \end{frame}  \end{document}

I know that you can change the itemsep of an itemize environment by loading the enumitem package. To the extend of my knowledge, this method has the disadvantage that every time I use an itemize/enumerate environment to manually adjust itemsep.  Thus, I want to ask if there is a method (preferably) or a package in which I can set itemsep=0.2cm (or its corresponding value in pt) globally (i.e. for my entire document).  Thanks in advance!  PS: A workaround is to record a macro with my settings (itemsep, label, etc..). However, I don't think that is a proper way to handle such thing


Is there an easy way to compute the size (Lebesgue measure) of the set $$S_n(a):=\{(x_1,\ldots,x_n)\in\mathbb{R}^n:x_1+\cdots+x_n<a\text{, and }x_i>0\}.$$ Using integration I computed that $$m(S_n(a))=\frac{a^n}{n!}.$$ But the computation is tedious, and I was wondering if there are more concise/direct ways of proving it.  Computation: $$ \begin{align} m(S_n(a)) &= \int_0^a\int_0^{a-x_1}\cdots\int_0^{a-x_1-\cdots-x_{n-1}}dx_n\cdots dx_1 \\ &= \int_0^a\int_0^{a-x_1}\cdots\int_0^{a-x_1-\cdots-x_{n-2}}(a-x_1-\cdots-x_{n-1})dx_{n-1}\cdots dx_1 \\ &= \int_0^a\int_0^{a-x_1}\cdots\int_0^{a-x_1-\cdots-x_{n-3}}\frac{-1}{2}(a-x_1-\cdots-x_{n-1})^2\big|_0^{a-x_1-\cdots-x_{n-2}}dx_{n-2}\cdots dx_1\\ &=\int_0^a\int_0^{a-x_1}\cdots\int_0^{a-x_1-\cdots-x_{n-3}}\frac{1}{2}(a-x_1-\cdots-x_{n-2})^2dx_{n-2}\cdots dx_1\\ \end{align} $$ and so on...

Let $T_n=\{x_i\ge0:x_1+\cdots+x_n\le1\}$. I know $T_n$ is tetrahedron.  My question: How can I compute the volume of $T_n$ for every $n$?


For the purposes of collaboration, I want to create a number of short commands or environments that will color the text within its scope so as to identify the author.  My first thought was to simply create a number of new commands along the lines of the suggestions given . But I'm imagining that the various collaborators would be writing several pages of text at a time and I don't know whether large blocks of text (and perhaps multiple new environments within that text) brings with it issues that would decide in favor of using new commands or environments.  Is there a reason to choose one or another route to coloring large blocks of text?  In general, when is it better to use a new command vs. a new environment (if there is any substantial difference)?   UPDATE: Well I think I've come up with a partial answer: making commands following the model given in the linked answer (\newcommand{\red}[1]{\textcolor{red}{#1}}) won't allow you to place multiple paragraphs within the scope of one command instance. Each paragraph requires a new instance of the coloring command (unless I'm doing something wrong). This would seem to be one reason to go the environment route.  FURTHER UPDATE: It turns out that the limitation of the command approach was a limitation of \textcolor, not some general limitation on new commands. Using \color allows you to color multiple paragraphs.

The first time I learnt LaTeX, I thought \newcommand properly fits for inline mode and \newenvironment for displayed mode.  Later I noticed it is not correct. So the question is   What is the rule of thumb when deciding whether we should use one over the other one?


At the end of the Massacre at Hardhome in the 5th season of Game of Thrones, the army of the dead stood on the shores watching as Jon Snow and the survivors very slowly rowed away. From a narrative standpoint, it’s easy to see why the show needed the ice zombies to stop here, as it delivered one of the show’s most impressive and terrifying moments — the raising of the dead with a hand gesture by The Night’s King. But it also raises some fundamental questions about this undead army. Are they afraid of water?

After watching 6 seasons of Game of Thrones, we know that the only roadblock for White Walkers is "The Wall" to stop them from attacking Westeros. However, we see that King Stannis attacked wildlings through a ship route without crossing the Wall.  What is stopping the White Walkers from doing the same? They can ask wights to make Ships or rowboats. They have a lot of forests to get wood for making ships. They can simply land at the coast of the North and attack Winterfell or whatever they want.


Example:  Let $T : V \to W$ and $S : W \to U$ be two one to one linear transformations.  Would $S \circ T$ also be one to one?

I am asked to consider f(x) and g(x) which are both 1-1 functions on their respective domains. I have been asked to show f ∘ g is a 1-1 function and then a followup statement of if f ∘ g is 1-1 does that mean f(x) and g(x) are both 1-1 on their domains.  The problem I am having with this question is how do I show the result? I understand when a function is 1-1 over a certain domain and I have tried composing my own functions but am unsure how I prove the result is true because I do not believe providing an example of two functions f(x) and g(x) where the first statement holds is really what I am supposed to do.  Sorry for posting again so soon, especially for such a similar and straightforward question.  Thank you.


In the following two sentences, what is more appropriate and why - hence or therefore?  I Missed the bus hence I had to take a cab I Missed the bus therefore I had to take a cab  Or they can be replaced for each another?

I was taught that, at least, 'therefore' and 'so' and can be used interchangeably, one being informal, the other formal. But, even when written, replacing 'so' with 'therefore' doesn't seem correct.     I was tired so I fell asleep.   ...     I was tired therefore I fell asleep.   Am I even allowed to use therefore as a conjunction here? The dictionary says I can, but it would seem more suitable to say:     I was tired and therefore I fell asleep.   I realise hence and thus (and even ergo) are rarely used, but where do they fit into this?


About a week ago, i bought a Desktop PC and decided to install Ubuntu 18.04 as it's starter OS (There were no files, no drivers, anything inside the HDD. It was clean), the installation (i made another un-answered thread about that here: ) was interrupted halfway through and tried again, this time leading to an un-ending 'Ubuntu' loading screen after it finished installing.  Tried installing Ubuntu 16.04 instead, had the same issue. Then Windows 10, had an eternal loading screen. And finally Windows 7, same thing as before.  I came to the conclusion the issue was the physical hard drive, but i'm not sure what exactly is the problem.

I tried to fix my hard drive using Ubuntu but I encountered an error message and didn't know how to proceed. I need to fix my bad sectors   fsck /dev/sdb   fsck from util-linux 2.20.1   e2fsck 1.42.5 (29-Jul-2012)   fsck.ext2: Permission denied while trying to open /dev/sdb   You must have r/w access to the filesystem or be root


What are some examples of English words that got taken into use in a foreign language in a changed state, and then subsequently re-entered the English language in state B or even state C.

Wikipedia mentions several English words that have been :   Anime comes from animation and has been reborrowed into English to mean Japanese-style animation. Puroresu comes from professional wrestling and is a term for Japanese-style professional wrestling. Kosupure comes from cosplay (an abbreviation of costume play) and refers to the practice of dressing in costumes of anime and video game characters.    Do you know other examples of word reborrowings from Japanese or other languages back into English, or vice versa?


I need to multiply a column in a file with float numbers, say with (1.0 + 0.25) I have a extracted column 3 ( with Numbers) with awk command from file file1.txt awk '{ print $3 }' file1.txt > coloumn1  1.0   1.2   1.3    I want to multiply all column values with (1.0 + 0.25)to achieve the following values. requirement is to use different p1 values. p1 is 1.1 ( 1.0*(p1+0.25))   ( 1.2*(p1+0.25))   ( 1.3*(p1+0.25))    1.250   1.500   1.625    My script is #bin/bash p1=1.0 val=`echo $p1 + 0.25 | bc` awk -F, '{$1*=$val}1' OFS=, coloumn1 > coloumn_mod  But above awk command is not returning the expected result , Could you please help correcting the above command ?

Here is my script (to find the files that contain a specified pattern):  find . -type f \     -exec awk -v vawk="$1" '/'"$vawk"'/ {c++} c>0 { print ARGV[1]; exit 0 } END { if (! c) {exit 1}}' \{\} \;   I would like to use my script with an argument §:  MyScript.sh pattern   My problem is that I don't manage to put the $1 variable in awk.  When I try to debug my script  bash -x MyScript.sh pattern   Here is the output :  + find . -type f -exec awk -v vawk=pattern '// {c++} c>0 {print ARGV[1] ; exit 0 } END { if (! c) {exit 1}}' '{}' ';'   The $vawk variable seems to be empty.  Any idea?


Is there a name for this type of sentence: "The higher the temperature, the higher the pressure"?    Such a word grouping is generally accepted as a sentence in science.

Is     The more, the merrier!   a sentence? It doesn't seem to have a main verb, so I'm inclined to say no, but it certainly functions as a sentence in everyday speech.  I can think of three ways of analysing it:   It's a sentence with no main verb. Is this even possible? It's a sentence with an implicit verb: something like The more we have, the better! It's not a sentence. But then, what is it?


I did   fdisk -l   and found that I have 15 different ramdisks which are all called /dev/ram* (where * is a number between 1 and 15.)  This seems weird, but I'm not a hardware specialist so I don't really know if they are all needed or if I should just change/delete some of them. So, is this normal and should I leave it alone, or should I change something here?

Ever since I upgraded to 15.10, fdisk -l reports 16 ram disks (/dev/ram0 ... /dev/ram15). I'm a bit unsure what those are needed for. Is it safe to delete them? If not, how can I get rid of that fdisk output?


What's the average performance of long term stock investors in terms of % profit per year?  I want to know how I am doing compared to other people.  Is there such a statistic?

I've heard the number 7% thrown around a bunch of times, but I am struggling to find reputable data to back it up.   All I found was a quote from Warren Buffet that I couldn't find an original source for and data assembled by individuals on their personal websites. Is there something from an organization such as Market Watch making a statement about this?  I'm hoping to specifically find what the 10 or 20 year return is for investing in the S&P 500 index fund or another diversified portfolio option.


I have some associated categorical dependent variables that are ordinal in nature (with 4 or 5 categories). If I want to see the effect of a set of independent variables (which can be both continuous and categorical) what is the right way to perform the regression?   Should that be a multivariate generalized linear model? Actually if I performed separate regression for each DV, I would use ordinal logistic regression. But as the variables are associated, I am afraid, that will be misleading to use in my case!   What should be the right procedure? Can SPSS handle this? A reference that I can follow is cordially expected.

I have some dependent variables related to the growth of a company having categories like (e.g. for variables indicating net profit, financial turnover etc.)   (1) decreasing,   (2) stable,   (3) increasing and   (4) rapidly increasing.  Now these variables are associated and ordinal in nature. I want to see the effect of a set of co-variates on these dependent variables. I understand that separate logistic regression will result in wrong formula of the variance and thus will produce wrong p-values. But what kind of regression should I run with more than one associated dependent categorical variables? Should that be a GEE model? Or anything else like multivariate regression (GLM)?   Can SPSS or R perform this?   Besides, I would like to have your suggestion regarding whether I should rather consider these variables as nominal and take "stable" as the reference category so that interpretations are more meaningful?  Kind regards.


I always notice that my designs look good but buttons and other clickable elements don't look clickable. Can you provide any tips or links that can help me?

I'm creating a flat-ish responsive website, which basically is an online résumé.  I'm displaying skills (but it could be whatever) in a grid system. Each skill is clickable, to display some information about it (level, etc.).  Here is a screenshot (from a mobile device view) of what I've made at this point.   I know, as the conceptor of the design, that it is clickable. However, I feel like it is not obvious - or not enough at least - for any random user.  On a computer browser, it is easy to have visual change on hover, but on tablet / mobile, I can't figure out how to do.  Does anyone has a visual trick to basically say hey, click on me? I think I could add a little pointer in the corner of each tile but I'm not sure it would look good.    UPDATE  According to some suggestions, I have changed icons to be more relevant. Thus, I can delete the label.  I also lighten a bit the background-color of buttons, in order to accentuate the constrat between the two shades of blue.


For $ n \ge 1$ , $F_1=F_2=1$  for $n \ge 3$ ,$F_n=F_{n-1}+F_{n-2}$  prove that  $\gcd(F_{n+1},F_n)=1$  I'm trying to prove by induction  we prove that when $n=1$, the equation holds,  $\gcd(F_{1},F_1)=1$ next when $n=k$, suppose  $\gcd(F_{k+1},F_k)=1$ is true, we prove $P(k+1)$ is true using induction hypothesis.  We're trying to prove that $\gcd(F_{k+1+1},F_{k+1})=1$.  We know that $F_{k+2}=F_{k+1}+F_{k}$, does this mean   $\gcd(F_{k+1+1},F_{k+1})=F_k$?  or  $F_{k+2} =1. F_{k+1} +F_k$? or $F_{k+2} \equiv  1 \bmod F_{k+1}$?  then  $$\gcd(F_{k+1+1},F_{k+1})=\gcd(F_{k+1}+F_k,F_{k+1}) =\gcd(F_{k+1},F_{k+2}  \bmod F_{k+1})=\gcd(F_{k+1}+F_{k})=1$$  I'm not too sure about when $F_{k+2}=F_{k+1}+F_{k}$, is this have same meaning as  $\gcd(F_{k+1+1},F_{k+1})=F_k$? or  $F_{k+2} =1. F_{k+1} +F_k$.   Is there an alternative proof?

I have looked a bunch of solutions of this problem on the web. But I want to know that whether my solution is correct or not. My solution is as follows  Proof(By Induction)  $P(n)$:The Fibonacci numbers $F_n$ and $F_{n + 1}$ are relatively prime.  Base Case: $P(0)$ is true because $F_0 = 0$ and $F_1 = 1$ are relatively prime.  Inductive Step:   Assume $P(n)$ to be true. Now to show that for $n \geq 0$, $P(n) \implies P(n + 1)$  $\implies \gcd(F_n, F_{n + 1}) = 1$  $\implies s(F_n) + t(F_{n + 1}) = 1$  $\implies s(F_{n + 2} - F_{n + 1}) + t(F_{n + 1}) = 1$  $\implies (t - s)(F_{n + 1}) + s(F_{n + 2}) = 1$  $\implies \gcd(F_{n + 1}, F_{n + 2}) = 1$  $\implies P(n + 1)$ is true  Thus, by induction $P(n)$ is true for all $n \geq 0$.


I’m a Nigerian , I have been invited by the British army for an assessment next month , my dad is willing to sponsor my Traveling expenses and my brother who is in the British army and a citizen of United Kingdom is will accommodate me, I am unemployed currently do my apprenticeship in my fathers company ,my dad has paid N1,500,000 (£3000) into my account with a letter that represents that ,my father is a business man and I have paperwork to back that up  , I have also added my father assets in Nigeria  to my visa application..do I need to bring my fathers company bank ste together with my own..or should I just bring only mine since he has already sent the money to my account???

The UK Visas and Immigration Directorate publishes  that provides helpful tips that can result in successful visa applications. Section 2 of this guidance opens is entitled "other documents you may want to provide" (emphasis mine).  Section 2: other documents you may want to provide – all visitors This section provides guidance on the types of documents that you may want to provide to help us consider your application against the Immigration Rules. Previous travel documents/passports, which show previous travel. Financial documents showing that you have sufficient funds available.  These must clearly show that you have access to the funds, such as:  bank statements building society book proof of earnings such as a letter from employer confirming employment details (start date of employment, salary, role, company contact details) where a third party (who is either in the UK or will be legally in the UK at the time of your visit) is providing financial support to you e.g. a business, a friend or a relative, documents to show that they have sufficient resources to support you in addition to themselves and any dependant family should be provided   The first item is "bank statements" and this ties in with the , which says...  evidence that you can support yourself during your trip, eg bank statements or payslips from the last 6 months  (Note 'eg' is a Latin abbreviation meaning "for example"; this appears to be optional rather than a fixed requirement.) Question: How should someone interpret this such that the chances of success are maximized? How many statements should I submit? What are they looking for and what do my bank statements tell about me?


I have apache2 setup and serving files successfully from locations such as:  /var/www/example.com  where ownership and permissions were set like this:  sudo chown -R $USER:$USER /var/www/example.com  sudo chmod -R 755 /var/www  resulting permissions look like:  drwxr-xr-x 6 tim tim 4096 Aug 23 23:22 example.com/  drwxr-xr-x 5 tim tim 4096 Aug 24 14:45 www/  and apache2.conf includes:  ServerName 127.0.0.1  and hosts includes  127.0.0.1 localhost  sudo service apache2 restart  a browser successfully loads:  localhost/example.com    the above is all good but...  I get 403s when I attempt to setup files to be served from an ntfs partition with:  sudo gedit /etc/fstab  /dev/sda3 /media/tim/Data  ntfs-3g permissions,locale=en_GB.utf8    0   2  sudo umount /media/tim/Data  sudo mount -a  and use the same chown and chmod method above:  sudo chown -R $USER:$USER /media/tim/Data/www/example.com  sudo chmod -R 755 /media/tim/Data/www  with a symbolic link such as:  /var/www/ $ ln -s /media/tim/Data/www/example.com  The symbolic link works with these permissions: lrwxrwxrwx 1 tim tim 36 Aug 24 14:45 example.com -> /media/tim/Data/www/example.com  and the permissions for the folders look like this:  drwxr-xr-x 1 tim tim 8192 Aug 24 15:16 /media/tim/Data/www/example.com  drwxr-xr-x 1 tim tim 0 Aug 23 23:24 /media/tim/Data/www/    i have also tried  setting up virtualhost successfully on the local ext4 file system, but again got 403s if the virtualhost pointed to /media/tim/Data/www/example.com or the symbolic link /var/www/example.com  I've seen others apparently solve the issue with the fstab method, and as far as I can tell my permissions are also set correctly this way, but still fails.  Answers appreciated.

I'm a beginner in Ubuntu hoping to find a better web development environment than WIndows. I'm trying to access http://localhost but its always giving me a forbidden error. I've installed php, mysql, and apache separately. Files/web_files is also my web directory in windows which when I access on windows is D:/Files/web_files and on ubuntu is media/Files/web_files. I also restart apache after editing the default file located in etc/apache2/sites-available Am I editing the wrong file? Please help.  <VirtualHost *:80>     ServerAdmin webmaster@localhost      DocumentRoot /media/Files/web_files     <Directory />         Options FollowSymLinks         AllowOverride None     </Directory>     <Directory /media/Files/web_files/>         Options FollowSymLinks         AllowOverride All         order allow,deny         allow from all     </Directory>      ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/     <Directory "/usr/lib/cgi-bin">         AllowOverride None         Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch         Order allow,deny         Allow from all     </Directory>      ErrorLog /var/log/apache2/error.log      # Possible values include: debug, info, notice, warn, error, crit,     # alert, emerg.     LogLevel warn      CustomLog /var/log/apache2/access.log combined      Alias /doc/ "/usr/share/doc/"     <Directory "/usr/share/doc/">         Options Indexes MultiViews FollowSymLinks         AllowOverride None         Order deny,allow         Deny from all         Allow from 127.0.0.0/255.0.0.0 ::1/128     </Directory>  </VirtualHost>   Update If I used var/www instead it works like magic.  DocumentRoot /var/www <Directory />     Options FollowSymLinks     AllowOverride None </Directory> <Directory /var/www/>     Options FollowSymLinks     AllowOverride All     order allow,deny     allow from all </Directory>   Here's the output from the mount command  /dev/loop0 on / type ext4 (rw,errors=remount-ro) proc on /proc type proc (rw,noexec,nosuid,nodev) none on /sys type sysfs (rw,noexec,nosuid,nodev) none on /sys/fs/fuse/connections type fusectl (rw) none on /sys/kernel/debug type debugfs (rw) none on /sys/kernel/security type securityfs (rw) none on /dev type devtmpfs (rw,mode=0755) none on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620) none on /dev/shm type tmpfs (rw,nosuid,nodev) none on /var/run type tmpfs (rw,nosuid,mode=0755) none on /var/lock type tmpfs (rw,noexec,nosuid,nodev) none on /lib/init/rw type tmpfs (rw,nosuid,mode=0755) /dev/sda2 on /host type fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,allow_other,blksize=4096) binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,noexec,nosuid,nodev) gvfs-fuse-daemon on /home/wern/.gvfs type fuse.gvfs-fuse-daemon (rw,nosuid,nodev,user=wern) /dev/sr0 on /media/2022_21092011 type udf (ro,nosuid,nodev,uhelper=udisks,uid=1000,gid=1000,iocharset=utf8,umask=0077) /dev/sda3 on /media/Files type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096,default_permissions) /dev/sda1 on /media/System Rese   And here's the output from ls - laR/media  ls: cannot access -: No such file or directory ls: cannot access laR: No such file or directory /media: 2022_21092011  Files  System Reserved   So I'm wondering if this is an issue in the filesystem or its permissions. But I don't think it has something to do with permissions since I can perfectly edit the files in media/Files/web_files without having to run it as a superuser.  Thanks for those who has taken their time to help me so far.


I looked up guides to install ubuntu, but they all say that you can choose the option: "install along windows". But The option is long gone, so i read... . Now i shrinked my windows partition, and get a new extra partition. When i install ubuntu using a usb device, everything goes well, but when i need to choose a partition to install ubuntu on, i can't use the partition i created because it's not usable... . So i think i have to format the partition but i don't know how.  Can someone help me?  P.S. :  The main goal is to run a dualboot system. I'm using windows7

I'd like to see the full How-To on how to use manual partitioning during Ubuntu installation. The existing guides (at least those I found here) cover only automatic part and leave untouched the manual part (or extremely short and contain no pictures).  I'd like to cover such situations:     If your disk contains other systems:


I have a 2018 Macbook pro with MacOS 10.13.6.  To have a more stable connection (compared to WiFi) I got a "Belkin USB-C to Ethernet Adapter".  Initially, the adapter had a self-assigned IP which I fixed by changing how the IPv4 in Network settings is configured from DHCP to DHCP with manual address. Now the status is green and the device is assigned an IP address. However, there is still no connectivity through this device.  Any help is appreciated.

Cannot connect MacBook Pro (Retina, 15-inch, Mid 2015) (10.13.3) to the internet through my Apple USB Ethernet Adapter. I am receiving this error under System Preferences/Network:   "Apple USB Ethernet Adapter has a self-assigned IP address and will not be able to connect to the Internet." IP Address: 169.254.59.248 Subnet Mask: 255.255.0.0   I can connect to the internet with the same ethernet port on my Windows 10 machine. When I replace the IP address with a the Wi-Fi IP address I use to successfully connect to the same network under "Using DHCP with manual address", the Apple USB Ethernet Adapter icon is green and displays the message "Apple USB Ethernet Adapter is currently active and has the IP address xx.xx.xx.252." However there is no actual internet connection (i.e., I cannot visit any website).  According to  to a similar problem, I can:   Find and disable whatever firewall is intercepting the DHCP return traffic. According to System Preferences/Security & Privacy/Firewall, my firewall is off. Is there anywhere else I can check for additional firewalls? Would firewalls somehow impact ethernet and Wi-fi differently?  Inspect the network traffic or the router logs to see if and why the Mac DHCP broadcast packet is being ignored. How do I check network traffic on my Mac? I am comfortable using the terminal.   I have also tried steps listed as potential solutions in :   To reset the firewall, go to the /Macintosh HD/Library/Preferences/ folder and remove the file called "com.apple.alf.plist," and then restart your computer. On my computer I went to /Library/Preferences/ and ran sudo rm com.apple.alf.plist If that was already set, try the "Advanced" button, then "Renew DHCP Lease" Removing their "Ethernet" config from the Network settings and then re-adding   Does anyone have other suggestions? Thanks in advance


My mum and dad want a divorce and I don't know what I can do. My dad likes another woman and my mom already asked three lawyers for the divorce. My BFF has heard some things about this. My life is already a dark, gloomy cloud, and I am very very unlucky! I don't know what to do. Please Help Me!

I am a young teenager, younger than 16. (I do not want to give my age online)    My dad told me he wants a divorce, but I don't want my parents divorced. My dad says he can't stand my mom anymore.  My dad is older than 45 and my mom is older than 40.    If it happens, I would choose to stay with my mom. My dad can cook and drive, but my mom can't. There's a school bus in high school though.    What can I do to prevent this divorce?


my karbonn s2 has 512 MB RAM but it is always shows 85 % full I have installed RAM cleaner app but not happy with it. sometimes my phone hang down. what can be done to increase the memory (RAM) ?

I'm new to the ICS os, coming from Gingerbread from another phone. The phone's quite nice and fast when I first used it, but just this morning it started exhibiting weird actions. Camera360 doesn't open up automatically when I click it, the Camera closes for no reason, Pocket restarts when an article has an image, and TTPod resets the song to the previous song on my widget in the middle of a new song I'm playing.  I checked out the ram, and and was surprised to see 500+ mb used, 0 mb available. I looked at the list of programs and I see the usual culprits like Facebook, but the ram they're using doesn't add up to 500+ mb. Yeah, I know that the whole ram indicated isn't usable by the apps, but I don't think I've done anything to warrant the 0 mb. I close my apps. There are times when there's free 4 to 5 mb, but I think that too shouldn't be the case. I tried installing Advance Task Killer, it listed less than 10 apps, killed it, still the ram is what it is above.   I did a reboot, and now it reads 300+ mb usage, 200 something free.   What can I do? How do I ensure an app's closed on ICS? I installed GoLaucher because it has a handy task killer and I can see the ram freed in an instant, but I would like to know if there's a better way to handle the RAM.


SQL Server provides ways to analyze indices that should be added to a database, but is there a way to identify indices that shouldn’t exist, or be replaced be better ones in SQL server?  For example:   Indices that uses a lot of space, cause locking during inserts and aren’t well used Duplicate, or nearly duplicate indices that could be replaced by a single index   Please read carefully before marking as a duplicate of another question.

I am working on a Data warehouse. I have tables with up to 200M records. Some of these tables have around 20+ indexes (I can't provide a reason why they have been created in the first place). This is making the job of maintaining these indexes too painful and has a direct impact on the DWH import job in both performance and run time.  How can I find the least used indexes on each table? (in order to get rid of them)


I keep getting this error in my program where I am calling the method getValWords and the error say the following "The method getValidWords(String) in the type anothertry is not applicable for the arguments (File)".   This is a sample of my code.       File file = new File (args[0]);     List<String> words = getValidWords(file);       Collections.sort(words);      System.out.println(words.toString());      }  public static String[] getValidWords(String s) {     s = s.replaceAll("[0-9]\\p{L}+", " "); // Removes any word starting with a number     s = s.replaceAll("\\s+", " "); // trims extra whitespace "    " into " "     return s.split(" "); }

I've been using the idiom below for some time now. And it seems to be the most wide-spread, at least on the sites I've visited.  Is there a better/different way to read a file into a string in Java?  private String readFile(String file) throws IOException {     BufferedReader reader = new BufferedReader(new FileReader (file));     String         line = null;     StringBuilder  stringBuilder = new StringBuilder();     String         ls = System.getProperty("line.separator");      try {         while((line = reader.readLine()) != null) {             stringBuilder.append(line);             stringBuilder.append(ls);         }          return stringBuilder.toString();     } finally {         reader.close();     } }


I have the following question :  $G$ is a group  ִ$a\in G$ while $O(a)=n$ then $O(a)=O(a^{-1})$  What I did :  We know that :  $(a^n)=e$  we know that   $(a^n)^{-1}=(a^{-n})^=(a^{-1})^n$  Well, I don't know that to do now. I'm not sure I approach this correctly.  Any ideas?  Any help will be appreciated.

If $a$ is a group element, prove that $a$ and $a^{-1}$ have the same order.   I tried doing this by contradiction.    Assume $|a|\neq|a^{-1}|$  Let $a^n=e$ for some $n\in \mathbb{Z}$ and $(a^{-1})^m=e$ for some $m\in \mathbb{Z}$, and we can assume that $m < n$.  Then $e= e*e = (a^n)((a^{-1})^m) = a^{n-m}$. However, $a^{n-m}=e$ implies that $n$ is not the order of $a$, which is a contradiction and $n=m$.  But I realized this doesn't satisfy the condition if $a$ has infinite order. How do I prove that piece?


So according to  and  I should be using \(...\) instead of $...$ and \[...\] instead of $$...$$.   But what if I have a document where I've already used dollar signs a bit? How do I convert them? A simple find and replace won't work since:   It won't care whether $$ is a beginning or ending; and I use the dollar sign in the text (to refer to the currency).    Does anyone have a neat tip for this?

Is there an editor or IDE (or a script) for substituting the TeX-Commands $ and $$ for opening and closing math regions into the corresponding LaTeX-Commands \(,\) and \[,\]? I'm sure there is a tool - and I'm searching for. I think, this will result in better readable code. A simple search and replace wont do that - but with regular expressions, that should not be problem. I simply do not want to invent the wheel a second time.


I noticed that in C# there are both a byte and Byte data type. They both say they are of type struct System.Byte and represent an 8-digit unsigned integer.   So I am curious as to what the difference if any is between the two, and why you would use one over the other.  Thanks!

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


I have VSCode installed on Ubunutu 14.04 64-bit but when it's launched from terminal there is this error:   [6303:0615/111654:ERROR:browser_main_loop.cc(170)] Running without the SUID sandbox! See https://code.google.com/p/chromium/wiki/LinuxSUIDSandboxDevelopment for more information on developing with the sandbox on. bash: cannot set terminal process group (-1): Inappropriate ioctl for device bash: no job control in this shell   Is this something I should fix or it is coming from VSCode?  Also is there a way to launch it from terminal but terminal not to stay open all the time?

How do I run a program in the background of a shell, with the ability to close the shell while leaving the program running? Lets say my UI is having problems or for some reason, I need to boot up a program from the terminal window, say, nm-applet:  nm-applet   When it's started, it occupies the foreground of the terminal window.  Is there any simple way to run the program in the background without needing to leave the terminal open or have it occupy the whole terminal?  On that note, I did find a way to run programs from the terminal and have it allow for other inputs, by appending an ampersand (&) to the command as such:  nm-applet &   But this isn't much use as any processes started in the terminal are killed once the terminal is closed.


How can I replace mysql_real_escape_string in PDO to keep my code still secure:  (mysql_real_escape_string no longer supported in PHP v7.x)  I would appreciate if somebody could provide an example for this code line: "ORDER BY " . mysql_real_escape_string($order) . " LIMIT :numRows";"  Full code below:   public static function getList( $numRows=1000000, $order="pageID ASC" ) {     $conn = new PDO( DB_DSN, DB_USERNAME, DB_PASSWORD );     $sql = "SELECT SQL_CALC_FOUND_ROWS *, UNIX_TIMESTAMP(pagePublicationDate) AS pagePublicationDate FROM web_pages             ORDER BY " . mysql_real_escape_string($order) . " LIMIT :numRows";      $st = $conn->prepare( $sql );     $st->bindValue( ":numRows", $numRows, PDO::PARAM_INT );     $st->execute();     $list = array();      while ( $row = $st->fetch() ) {       $article = new cmsEngine( $row );       $list[] = $article;     }      // Now get the total number of website pages that matched the criteria     $sql = "SELECT FOUND_ROWS() AS totalRows";     $totalRows = $conn->query( $sql )->fetch();     $conn = null;     return ( array ( "results" => $list, "totalRows" => $totalRows[0] ) );   }

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?


We have been under recent attacks from a hacker and we need to be able to stop all IP addresses from editing files except for the ones at our office.  I know how to do this via an .htaccess file however I am at a loss when it comes to just a server side thing.  Unfortunately we use a server at HostGator and they couldn't tell me much. I am not much of a server person, so I am not even sure if this is the best route.  Any guidance or help on the subject matter would be greatly appreciated.    Thanks!

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 a table (t0), in my Postgres DB, with data that looks something like this:  t1_id  t2_id 1      1       2      1 2      1 4      null 4      null 5      null   And I have a query to return my desired results of:  t1_id  t2_id 1      1 4      null 5      null   My query looks something like this:  (   SELECT DISTINCT ON (t2_id) t1_id, t2_id   FROM t0   WHERE t2_id IS NOT NULL ) UNION ALL (   SELECT DISTINCT ON (t1_id) t1_id, t2_id   FROM t0   WHERE t2_id IS NULL )   Is there a faster way to do an operation like this? It's not too bad, but I'm doing it in several places (with joins) and all these repeated queries seems to slow stuff down a bit. Seems like there must be a better way.  Here's the query in fiddle form:


I am using a Jquery plugin called Jquery Content Panel Switcher.  It does exactly what the title says, it switches out divs with ease.  The html for the page is:    One Two

   In each of my content panels I have a form.  In each form there is a table:

Rank 1

       Number	       Requirements

       1	       Info

       2	       More Info

   I am trying to fire off an action if a row gets clicked.  Here is the javascript I am using:  $(document).ready(function(){   $('#switcher-panel form table tbody tr').click(function(){      console.log("Clicked");    }); });   When I use the Jquery selector of $('#switcher-panel form table tbody tr') in my Chrome console, it finds the table and everything looks fine.  When I put it in my javascript file, nothing happens.  Some direction would be great.  Thanks for the help.

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


I have a .asp page that loads some frames and I need to access their content.  I tried to use jquery .contents() method by replicating the official example from the documentation but even that doesn't work.   Here's my code snippets  HOME.HTML  <!doctype html>     <meta charset="utf-8">   <title>contents demo</title>               MYCOM.HTML  <!DOCTYPE html>   <title></title>

MYCOM FRAME!

      Also using .load on the frame to ensure that its content is fully loaded does not work.  What am I doing wrong?

I would like to manipulate the HTML inside an iframe using jQuery.  I thought I'd be able to do this by setting the context of the jQuery function to be the document of the iframe, something like:  $(function(){ //document ready     $('some selector', frames['nameOfMyIframe'].document).doStuff() });   However this doesn't seem to work. A bit of inspection shows me that the variables in frames['nameOfMyIframe'] are undefined unless I wait a while for the iframe to load. However, when the iframe loads the variables are not accessible (I get permission denied-type errors).  Does anyone know of a work-around to this?


I'm trying to setting up a template HTML / CSS / Javascript.  My footer don't stay down.  As you can see if the page is full,  it works more or less good.  But if the page doesn't fills all the screen  the footer goes up.  If you don't have a good big screen resolution you don't see that. In this case push CTRL &  minus to see the problem (or CMD & minus on MacOs).  I love it and I want to use just that template.  I've tried also something that  footer {   position: fixed; }   but the footer had to follow the last section.  It's possible to set it to stay at the end of the page maintaining the same layout?  P.S. I prefer to do it only with CSS without using JS, because some browsers can't have it.  Thank U

I have a simple 2-column layout with a footer that clears both the right and left div in my markup.  My problem is that I can't get the footer to stay at the bottom of the page in all browsers.  It works if the content pushes the footer down, but that's not always the case.


I am using a commercial scraper with some light RegEx support, and I want to capture data (the odds, 3.13, 14.69 etc. etc.) from the text as seen below:  I have to match one variable at a time (it is how the scraper works), save it, repeat. The problem is that I can't match some numbers as seen above; for some reason the first digit before the decimal place is not captured. However ([\d]+.[\d]+) correctly matches everything. Any suggestions?

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 am currently writing my physics bachelors thesis and it is the first time i have written a document in latex. I have two questions:   The current document class is article, i have partitioned my thesis into sections and subsections. I have many equations in the main body which i reference in my explanations etc. As it stands, the equation label is up to about (200), and this is ugly to write everytime. I would prefer if i could number the equations by section and then by order, for example the 10th equation of section 3 (which might be located in subsection 3.2, for example) should be labelled (3.10). I know i can do this with the document class book, but i dont like the chapter style of this class and much prefer the section/subsection style. How might i get around this without manually labelling every equation?  I, like many other authors, did not start writing my thesis in chronological order. I instead started in section 2, then jumped to section 4 etc. Now i would like to write section 1, but i made the rooky mistake of not implementing automatic updating in my equation labelling. So for example, if i go to add an equation and label it (1),  the label of every equation coming after it gets its number increased by (1). The problem is that in my (already written) explanations i have referenced equation (1) which has just become equation (2). I realise that the only way to rectify this is to go through and do it manually, but for the future how does one implement automatic synchronizing  of the equation labels and equation references?    I would prefer answers for 1 and 2 which are compatible, if possible. Thank you!

Possible Duplicate:          I have written my thesis in document class 'article' (don't ask me why). Now I want to number my equations by sections, i.e. in section 1 they should go 1.1, 1.2, ..., in section 2 they should go 2.1, 2.2, ...  I don't want to change the document class (e.g. to 'report') because then I would have to change all sections to chapters, subsections to sections and because I fear a lot of other unintended consequences.   How can solve this?  Thanks for any help!


How do I insert  in my Stack Overflow question?  I have tried the code, HTML and other options, but I was unable to get my XML code snippet included in my question in a readable format.  <?xml version="1.0"?> <DTS:Executable xmlns:DTS="www.microsoft.com/SqlServer/Dts" >     <DTS:ConnectionManager>         <DTS:Property DTS:Name="ObjectName">DB2Source</DTS:Property>         <DTS:Property DTS:Name="Description"></DTS:Property>         <DTS:Property DTS:Name="CreationName">OLEDB</DTS:Property>         <DTS:ObjectData>             <DTS:ConnectionManager>                 <DTS:Property DTS:Name="Retain">0</DTS:Property>                     <DTS:Password DTS:Name="Password" Sensitive="1"></DTS:Password>                     <DTS:Property DTS:Name="ConnectionString">Data Source=develop;>                 </DTS:Property>             </DTS:ConnectionManager>         </DTS:ObjectData>     </DTS:ConnectionManager>      <DTS:ConnectionManager>         <DTS:Property DTS:Name="ObjectName">SQLDest</DTS:Property>         <DTS:Property DTS:Name="Description"></DTS:Property>         <DTS:Property DTS:Name="CreationName">OLEDB</DTS:Property>         <DTS:ObjectData>             <DTS:ConnectionManager>                 <DTS:Property DTS:Name="Retain">0</DTS:Property>                 <DTS:Password DTS:Name="Password" Sensitive="1"></DTS:Password>                 <DTS:Property DTS:Name="ConnectionString">Data Source=devc2400;</DTS:Property>             </DTS:ConnectionManager>         </DTS:ObjectData>     </DTS:ConnectionManager> </DTS:Executable>

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 .


Last fall, Tim Post ♦  that the primary reason that the accounts of underage users are deleted on sight is that there are laws against holding a minor's Personally Identifiable Information (PII). This has caused some consternation among both child users who have been banned and adult users who appreciated the contributions of child members that have been banned due to their age.  That rigamarole has led me to come up with the idea of proposing a programming site for underage users (tentative name: Stack Overflow for Teens) that would be more or less like a "regular" Stack Exchange site but where no PII would be collected from participants, or at least the gathering of PII would be completely voluntary and underage users found to have disclosed PII could continue participating after their PII was deleted (and perhaps a short suspension to teach them a lesson, especially if they have continued to provide PII after being warned that they are not old enough to do so).  Is a site that does not collect PII feasible? I have not (yet) proposed such a site because I (currently) lack the . The fact that underage users can't come onto the current Area 51 obviously doesn't help much, but that's not the focus of my question. I'm not asking about finding a community, but if I could find enough sympathetic adults to push through a proposal for a site for underage users, is this something that would be feasible or would Stack Exchange the company be likely to shoot it down as unfeasible either in a technological or business sense? E.g. "This is a great idea, but I have to close this proposal because the programming effort to remove all mandatory PII collection points would cost more than the company has, and the company's model anyways involves the monetization of PII so there's really little reason we would want this."

Yesterday my daughter watched me acting on my favorite SE site. She essentially said:      "Hey, that's cool. Can you recommend me a me a site there, where I could go to with my bunch of questions I have to ask?"   I admittedly had to deny her going here, since    She's going to get 12 that month (IIRC minimum age to legally participate at SE is 13, correct me if I'm wrong) Her english skills aren't well developed enough, to participate in internationally aimed sites   I've done more research then later and found 1, specifically designed for children's questions.  They're controlling more questions, and missing topics coming in from the interested children via e-mail.  I appreciate this model somehow, since (vs. a forum or SE), it's moderated by adults, and directed e-mail channels. Though adults have their "blinders" strapped on, and may totally miss the question. Also it keeps the kids safe from any totally off question attends of pedophile nature or such.    I've been infected now with the thought, if it would be possible to make up a site using the SE engine, that is specifically designed for    childrens asking mainly children answering decent moderation by adults, merely keeping them safe probably language specific, since we can't expect children to be familiar with english to ask well formed questions   I know it's kind of opinion based, but could you imagine one goes well and have the right controls at hand, to set up such kind of sites with SE (in Area51)?    As @Oded and others confirmed the point, that it generally wouldn't be legal for children younger than 13, besides parent's explicit agreement, which apparently can't be managed properly,   BREATHE  I still think that +13 year aged teens till at least 16 need to be treated as children, and it would be a good idea to give them protection level moderated sites.    1)Sorry it's in german, and that's also part of the question somehow. But I'd suppose everyone else here might be intelligent enough to extrapolate this for their native languages.


Prove that if $G$ is a group with $(ab)^{2}=a^{2}b^{2}$ for all $a,b\in G$, then $G$ is abelian.   I am not sure how to prove this. This is my work so far:  Proof so far: $G$ is abelian iff $ab=ba$. If $(ab)^{2}=a^{2}b^{2}$ for all $a,b\in G$, then $(ae)^{2}=a^{2}e^{2}=a^{2}$ or $a=a$ for all $a\in G$.     I am not sure whether I am approaching this correctly at this point, since it looks a little silly to me. If this is the right way, I am not sure how to continue.

If $G$ is a group show that if $(a \cdot b)^2 = a^2 \cdot b^2$ then $G$ must be abelian.   $\begin{aligned}(a \cdot b)^2 = a^2 \cdot b^2 & \iff (a\cdot b)\cdot(a \cdot b) = (a \cdot a)\cdot (b \cdot b) \\& \iff a \cdot (b \cdot (a \cdot b)) =a(a \cdot (b\cdot b)) \\& \iff (a^{-1} \cdot a) \cdot (b \cdot (a \cdot b)) =(a^{-1}\cdot a)(a \cdot (b\cdot b))\\& \iff (b \cdot (a \cdot b)) =(a \cdot (b\cdot b)) \\& \iff (b \cdot a) \cdot b =(a \cdot b)\cdot b\\& \iff (b \cdot a) \cdot (b \cdot b^{-1}) =(a \cdot b)\cdot (b \cdot b^{-1}) \\& \iff b \cdot a = a \cdot b\end{aligned}$  Thus $G$ must be abelian. Is this right? Is there less clunky way to write it if it's?


Stokes Theorem tells us that when $S$ is a piecewise-smooth surface that is bounded by a simple, closed, piecewise-smooth boundary curve $C$ with positive orientation and $\mathbf{F}$ is a vector field whose components have continuous partial derivatives on an open region in $\mathbb{R}^3$ containing $S$, then we have $$\int_C\mathbf{F }\cdot d\mathbf{r}=\iint_S \mathrm{curl }\ \mathbf{F}\cdot d\mathbf{S}.$$  The Divergence Theorem states that when $E$ is a simple solid region, $S$ is the boundary of $E$ with positive (outward) orientation, and $\mathbf{F}$ is a vector field whose component functions have continuous partial derivatives on an open region that contains $E$, then we have  $$\iint_S\mathbf{F}\cdot d\mathbf{S}=\iiint_V\mathrm{div }\ \mathbf{F}dV .$$  Since $$\mathrm{div}\ \mathrm{curl}\ \mathbf{F}=0,$$ then why doesn't $\int_C\mathbf{F }\cdot d\mathbf{r}=\iint_S \mathrm{curl }\ \mathbf{F}\cdot d\mathbf{S}$ always vanish?  For by the divergence theorem we have $$\int_C\mathbf{F }\cdot d\mathbf{r}=\iint_S \mathrm{curl }\ \mathbf{F}\cdot d\mathbf{S}=\iiint_V\mathrm{div }\ \mathrm{curl}\ \mathbf{F}dV =0.$$  But clearly this is not always true.   Where am I going wrong here?     Is this true only when $S$ encloses another region $V$? Does $V$ need to be bounded to apply the divergence theorem?  For some reason I feel like this is not the case, but I am not sure. Is there an obvious physical interpretation to the above result?   Many thanks for your consideration.  This has stumped me for quite some time and I would be very grateful to anyone who could shed some insight.

Let $A$ be any vector field, then by Stokes Theorem we have:  $$ \oint_{\gamma} \mathbf{A} \cdot d \mathbf{r}=\int_{S} \operatorname{curl} \mathbf{A} \cdot d \mathbf{S} $$  We can now apply Divergence Theorem to $\operatorname{curl}\mathbf{A}$, which using the fact that divergence of curl is $0$, gives:  $$ \int_{S} \operatorname{curl} \mathbf{A} \cdot d \mathbf{S} = \int_{\tau} \operatorname{div} ( \operatorname{curl} \mathbf{A} ) d \tau = 0 $$  So we could conclude for any vector field $A$:  $$ \oint_{\gamma} \mathbf{A} \cdot d \mathbf{r} = 0$$  What is wrong here?


If I have 5 slivers and one of them is a Thorncaster, will I need to assign the "1 damage to target creature or player" before or after my opponent declares blockers?  My guess is that it is as I attack, but I would like it to be after blockers are assigned.

I was guessing, since you actually target things instead of just dealing damage (similar to ), 's triggered abilities would actually go on the stack.  This came up in a separate game this past Friday when the Sliver deck attacked with two s, one , and two s while his opponent had a  as well as some 2/2.  The reason this even came up was because, if the triggers went on the stack, you could target things so they resolve in the following order:   Predatory Sliver targets Blood Artist, killing it. Predatory Sliver targets the 2/2, dealing one damage to it. Thorncaster Sliver targets the 2/2, killing it. and 5. Both Manaweft Slivers target the player, dealing one damage each to him.


I am a beginner in shell scripting. I am trying to change directory in a shell script by passing an absolute path as an argument. I am trying to do it with cd command but it's not working.  Any idea how to specify an absolute path? e.g, currently I'm in /home/malik1 and I want to  go to  /home/documents  What I've done:  if [[ -d "$1" ]]; then      cd $1   Correct me please if I'm doing it wrong.

I'm trying to write a small script to change the current directory to my project directory:  #!/bin/bash cd /home/tree/projects/java   I saved this file as proj, added execute permission with chmod, and copied it to /usr/bin. When I call it by: proj, it does nothing. What am I doing wrong?


If $m=a_1x+b_1y$, $n=a_2x+b_2y$ and $a_1b_2-a_2b_1=1$ then prove that $GCD(m,n)=GCD(x,y)$   Using a little bit of algebra, I arrived at: $$x=b_2m-b_1n\tag{1}$$ and $$y=a_1n-a_2m\tag{2}$$  But then I'm at a loss. What should I consider next? I did plug in a couple of values and it holds.

I'm having issues figuring out how to approach this problem:     Conclude that if $ad-bc = \pm 1$, then   $$\gcd(x,y) = \gcd(ax +by, cx + dy)$$   The fact that $\gcd(x,y) = \gcd(x+ky, y)$ is a very special case of this exercise   I believe there is a property that if $a = bq_1 + 0$ where 0 is r, then b divides a, and $b=\gcd(a,b)$  Is that at all relevant in this case?


Yesterday, the privilege tracker looked like this:    Today, it looks like this:    Note how the privilege overlaps the "Next Privilege" and triggering rep level.  (Chrome 67, Windows 7, 64-bit)

It seems "See votes, expandable user card" goes on a second line on the activity page of the user profile resulting in a pretty bad look:    You can see it live on  (though of course that may change any day now depending on their rep-growth).  I'm using Chrome Version 67.0.3396.99 (Official Build) (64-bit)


I am new to salesforce Lightning component and I meet a problem about how to navigate from one lightning component to another Lightning component,I want to know what is the best practise for it?  Now I just build a desktop app, in one component named studys I have a button and when I click the button I want to show the studyDetail component, and the studys component is not on the page.  How can I do this?

I have tried several ways to do this and have not reached enlightenment.  I have the same problem as outlined in this question   I was optimistic about using navigateToUrl but only .app have available urls, and .app cannot be seen in the salesforce1 mobile application. The components are not available via a direct url.  Here is what I have found:  This works in an app but not in mobile:  $A.get("e.myNamespace:navigateToView").setParams({"view": "bar"}).fire();  For this I cannot figure out what my recordId is for my lighning component. BTW, Also tried "componentId": "xxx" which I found in Dave Carroll's sublime manifest file:     $A.get("e.myNamespace:navigateToSObject").setParams({"recordId":"XXXXX2"}).fire();    The following also does not work:  $A.get("e.myNamespace:navigateToObjectHome").setParams({"scope":"myNamespace__expenseTracker__c"}).fire();  This works great and will take me to the homepage. I wish it worked for lightning components:  $A.get("e.force:navigateToURL").setParams({"url":"/_ui/core/chatter/ui/ChatterPage"}).fire();  Anybody familiar with a full lightning component example that demonstrations a navigation technique that works in salesforce mobile?


When should one wrap runtime/unchecked exceptions? What is the need? Why was CompletionException in java8 introduced? There are other examples as well in java and please include as many examples you want to include.

In Java (or any other language with checked exceptions), when creating your own exception class, how do you decide whether it should be checked or unchecked?  My instinct is to say that a checked exception would be called for in cases where the caller might be able to recover in some productive way, where as an unchecked exception would be more for unrecoverable cases, but I'd be interested in other's thoughts.


I am working about task for custom GIS application (about 70 users). It must show a map of region with custom objects from database (they will be triangles, lines, and icons with coordinates) . Users can add objects to the map by clicking the mouse. I am reading now about OSM, tiles servers and other information. But I don't know how to start creating the architecture of an application. Could you give some advices or examples of such applications (I think somebody has done such projects). Will I need ArcGIS and what plan? Or can I use only OSM with Leaflet?

I want to start working on a web map at work to map some of our statistics by city.    I have an idea, but I'm not exactly sure where to start.   Are there any definitive resources that provide step by step guidance on how to do this?


When I put a lens along the the sun it convert the sun energy to heat and maybe fire the substance beyond the lens. How could I determine the heat produced and what is the formula?

Why Magnifying glass(convex lens) produces heat when placed in front of sun?


Every time I open Blender the same project is opening, I don't know how I did this but I cant close the project and can't open a new project. I haven't saved the project that opens anywhere, this window opens every time.

I accidentally opened too many menus (or windows) and I want to reset them to default.  It is really annoying, and effecting my animation.  Thanks


I'm typesetting a Ph.D.-thesis and one of the chapters separates into two sub-chapters so I need it to count chapters like that:  1. Chapter one  2a. Chapter two A  2b. Chapter two B  3. Chapter three   Here problem that if we use following comment :  ***********************************************************  \usepackage{etoolbox}% http://ctan.org/pkg/etoolbox  %\usepackage{hyperref}% http://ctan.org/pkg/hyperref  \newcounter{subchapter}\renewcommand{\thesubchapter}{\alph{subchapter}} \makeatletter  % \patchcmd{<cmd>}{<search>}{<replace>}{<success>}{<failure>} \newcommand{\updatechaptercounter}{}  \patchcmd{\@chapter}{\@afterheading}{\updatechaptercounter\@afterheading}{}{}% Regular patch of \@chapter  %\patchcmd{\Hy@org@chapter}{\@afterheading}{\updatechaptercounter\@afterheading}{}{}% Hyperref patch of \@chapter  \makeatother  \providecommand{\theHchapter}{}%  \newcommand{\startsubchapters}{%    \setcounter{subchapter}{0}% Reset sub-chapter numbering    \renewcommand{\thechapter}{\arabic{chapter}\thesubchapter}% Update chapter number display    \renewcommand{\theHchapter}{\arabic{chapter}\thesubchapter}% Update chapter number display (for hyperref)    \renewcommand{\updatechaptercounter}{\addtocounter{chapter}{-1}}% Update chapter number    \let\oldchapter\chapter%   \renewcommand{\chapter}{\stepcounter{subchapter}\oldchapter}% Increment subchapter } \newcommand{\stopsubchapters}{%    \renewcommand{\thechapter}{\arabic{chapter}}% Reset chapter numbering    \renewcommand{\theHchapter}{\arabic{chapter}}% Reset chapter numbering (for hyperref)    \let\chapter\oldchapter% Restore regular \chapter command    \renewcommand{\updatechaptercounter}{}% Clear chapter counter update    \stepcounter{chapter}% Update chapter counter  }  \begin{document}  \tableofcontents  \chapter{chapter one}  \startsubchapters  \chapter{chapter 2 A}  \chapter{chapter 2 B}  \stopsubchapters  \chapter{chapter three}  ********************************************************************************   Respected Teachers/Friends  By using above text in LaTex, we have chapters contents are  1. Chapter one  2a. Chapter two A  3b. Chapter three B  4. chapter 4   Please solve this problem.

Currently I use a manually declared version of the chapter title. But the idea is to extend it to use specific and manually chosen number of the chapters.  I try to obtain numbers like this 1, 1b, 2, 2b, 3, 4. But for obtaining b, I want to specify it manually with for example an option in the \chapter command (something like this \chapter{...} for obtaining 1 then \chapter[b]{...} for obtaining 1b.   Do you have any ideas for obtaining this result?


Edit: I figured it out!  Answer is posted below. Thanks JSD!  I must be missing something because I thought this was a fairly simple process.  I have already copied the font over to my project folder.  I am trying to use the font in a UILabel on a Table Cell with this code:  UILabel *cellTitle = [[UILabel alloc] initWithFrame:CGRectMake(10, 10, 300, 40)]; cellTitle.font = [UIFont fontWithName:@"Source Sans Pro Black" size:50]; [cell.contentView addSubview:cellTitle];   It doesn't seem to be working.  The text appears but not with the custom font.  What am I missing?  EDIT:  Apparently if I use this code instead   cellTitle.font = [UIFont fontWithName:@"Source Sans Pro" size:50];   This works but it's only using the last font in my array of my pList file, which is only the Regular version of the font.  Has anyone ever had this issue before?  None of these codes work either:  cellTitle.font = [UIFont fontWithName:@"Source Sans Pro Bold" size:50]; cellTitle.font = [UIFont fontWithName:@"Source Sans Pro Regular" size:50];   This is the font in my font book:    PList file:

I would like to have an app include a custom font for rendering text, load it, and then use it with standard UIKit elements like UILabel. Is this possible?


If we are using php mysqli or PDO wrapper class, do they prevent SQL injection risks ?  E.g.      or     Always Use prepared statements and parameterized queries is advised by all experts.  wrapper class is useful for less coding in quick time and also help to reduce repeated coding.   Then how can we use wrapper class along with prepared statements and parameterized queries simultaneously ?  I am confused by this?  e.g.   example from -   Use prepared statements and parameterized queries  $stmt = $dbConnection->prepare('SELECT * FROM employees WHERE name = ?'); $stmt->bind_param('s', $name);  $stmt->execute();  $result = $stmt->get_result(); while ($row = $result->fetch_assoc()) { // do something with $row }   And with wrapper class, e.g. we use it as  $name = $database->filter($_POST['name']); $query = $database->get_results("select* from employee where name='$name'"); foreach ($query as $row){ // do something with $row }   Then where to use wrapper and where to use prepared statements ?   how to use both simultaneously ?   How to achieve sql injection prevention while using wrapper class ?

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 know that Ubuntu 11.10 has reached EOL status.  But is there a way to have it updated up until the EOL date of 5/9/2013?  I have looked at this , and it talks about how to get it done, but when I go to old releases, 11.10 is not listed.    So is the fact that it just got EOL status it needs a little time to move there or is there another way to have that update done?  The system is too old to have anything above 11.10.

Recently I have installed an older version of Ubuntu on my old machine. Whenever I try to install any software, I get an error saying it couldn't be found:  $ sudo apt-get install vlc Reading package lists... Done                Building dependency tree        Reading state information... Done     E: Couldn't find package vlc


Are attack rolls, made by enemy creatures, made behind a screen in Adventurers League? Is it at DM's discretion?  The answer would be useful in order to evaluate the usefulness of the feat Lucky.

If an enemy B attack a character A, where A has the Lucky feat, and A wants to spend a Luck point, in which moment can character A can spend that Luck point?     Can Character A see/know the natural result of Enemy B's roll before deciding whether or not to use a Luck Point?   If no, Can Character A see/know the natural result of Enemy B's roll after deciding to use the Luck Point,but before choosing which die?


In our deployment we have two servers. I want to connect it via host to host VPN:   On one server we have JMS broker on the second server we have JMS client and I want allow access to JMS broker only if it is pass via IPSec channel (JMS broker and client is only for the example).  Is it possible to check that packets pass via IPSec channel?

I'm using IPSEC in a tunnel mode.  How to make an iptables rule that will match only packets which arrived via IPSEC tunnel (i.e. after IPSEC decrypted them - not the IPSEC packets when they arrive and before decryption).   The point is to have a certain port which will be accessible only via IPSEC and inaccessible to the rest of the world.


A common way to reduce overfitting in a machine learning algorithm is to use a regularization term that penalizes large weights (L2) or non-sparse weights (L1) etc. How can such regularization reduce overfitting, especially in a classification algorithm? Can one show this mathematically?

I imagine that the larger a coefficient on a variable is, the more ability the model has to "swing" in that dimension, providing an increased opportunity to fit noise. Although I think I've got a reasonable sense of the relationship between the variance in the model and large coefficients, I don't have as good a sense as to why they occur in overfit models. Is it incorrect to say that they are a symptom of overfitting and coefficient shrinkage is more a technique for reducing the variance in the model? Regularization via coefficient shrinkage seems to operate on the principle that large coefficients are the result of an overfitted model, but perhaps I'm misinterpreting the motivation behind the technique.  My intuition that large coefficients are generally a symptom of overfitting comes from the following example:  Let's say we wanted to fit $n$ points that all sit on the x-axis. We can easily construct a polynomial whose solutions are these points: $f(x) = (x-x_1)(x-x_2)....(x-x_{n-1})(x-x_n)$. Let's say our points are at $x=1,2,3,4$. This technique gives all coefficients >= 10 (except for one coefficient). As we add more points (and thereby increase the degree of the polynomial) the magnitude of these coefficients will increase quickly.  This example is how I'm currently connecting the size of the model coefficients with the "complexity" of the generated models, but I'm concerned that this case is to sterile to really be indicative of real-world behavior. I deliberately built an overfitted model (a 10th degree polynomial OLS fit on data generated from a quadratic sampling model) and was surprised to see mostly small coefficients in my model:  set.seed(123) xv = seq(-5,15,length.out=1e4) x=sample(xv,20) gen=function(v){v^2 + 7*rnorm(length(v))} y=gen(x) df = data.frame(x,y)  model = lm(y~poly(x,10,raw=T), data=df) summary(abs(model$coefficients)) #     Min.  1st Qu.   Median     Mean  3rd Qu.     Max.  # 0.000001 0.003666 0.172400 1.469000 1.776000 5.957000   data.frame(sort(abs(model$coefficients))) #                                   model.coefficients # poly(x, 10, raw = T)10                  7.118668e-07 # poly(x, 10, raw = T)9                   3.816941e-05 # poly(x, 10, raw = T)8                   7.675023e-04 # poly(x, 10, raw = T)7                   6.565424e-03 # poly(x, 10, raw = T)6                   1.070573e-02 # poly(x, 10, raw = T)5                   1.723969e-01 # poly(x, 10, raw = T)3                   6.341401e-01 # poly(x, 10, raw = T)4                   8.007111e-01 # poly(x, 10, raw = T)1                   2.751109e+00 # poly(x, 10, raw = T)2                   5.830923e+00 # (Intercept)                             5.956870e+00   Maybe the take-away from this example is that two thirds of the coefficients are less than 1, and relative to the other coefficients, there are three coefficients that are unusually large (and the variables associated with these coefficients also happen to be those most closely related to the true sampling model).  Is (L2) regularization just a mechanism to diminish the variance in a model and thereby "smooth" the curve to better fit future data, or is it taking advantage of a heuristic derived from the observation that overfiited models tend to exhibit large coefficients? Is it an accurate statement that overfitted models tend to exhibit large coefficients? If so, can anyone perhaps explain the mechanism behind the phenomenon a little and/or direct me to some literature?


A textbox in a WinForm I have created is for e-mail. I'm checking the validation of the e-mail format.  The string seems to be ignoring the "." condition?  According to my test, it runs:   abcdef   - Not valid  (Correct) abcdef@gmail    - valid     (Incorrect) abcdefgmail.com      - Not valid     (Correct) abcdef@gmail.com     - Valid   (Correct)   Code Snippet:  Regex RX = new Regex("^[-!#$%&'*+/0-9=?A-Z^_a-z{|}~](\\.?[-!#$%&'*+/0-9=?A-Z^_a-z{|}~])*@[a-zA-Z](-?[a-zA-Z0-9])*(\\.[a-zA-Z](-?[a-zA-Z0-9])*)+$");

Over the years I have slowly developed a  that validates MOST email addresses correctly, assuming they don't use an IP address as the server part.  I use it in several PHP programs, and it works most of the time.  However, from time to time I get contacted by someone that is having trouble with a site that uses it, and I end up having to make some adjustment (most recently I realized that I wasn't allowing 4-character TLDs).  What is the best regular expression you have or have seen for validating emails?  I've seen several solutions that use functions that use several shorter expressions, but I'd rather have one long complex expression in a simple function instead of several short expression in a more complex function.


For example if $\lambda=\omega$ then $1+\omega=\omega$  If this is true, how to prove it formally? if not, could you make a counterexample?

For what ordinals does $1+\alpha=\alpha$ hold?   It obviously does not hold for naturals, (though I don't know how to prove it). My proposal is that it holds for any ordinal $\ge\omega$. Assume the contrary: $\exists \gamma \ge \omega $ such that $1+\gamma\ne\gamma$. Let's divide gamma by omega: $\gamma=\omega\tau+\rho$. So, $$1+\omega\tau+\rho\ne\omega\tau+\rho$$  $$\omega\tau+\rho\ne\omega\tau+\rho,$$ which is a contradiction.     For what ordinals does $2\alpha=\alpha $ hold?   My proposal is that it (1) holds for limit ordinals and (2) does not hold for non-limit ordinals.  Assume the contrary (1): $\exists$ a limit ordinal $\gamma$ such that $2\gamma\ne\gamma$.  Let's divide gamma by omega: $\gamma=\omega\tau+0$. So, $$2(\omega\tau+0)\ne\omega\tau+0$$ $$(2\omega)\tau\ne\omega\tau$$ $$\omega\tau\ne\omega\tau,$$ which is a contradiction.  Assume the contrary (2): $\exists$ a non-limit ordinal $\gamma+k, k>0$ such that $2(\gamma+k)=\gamma+k$. So, $$2\gamma+2k=\gamma+k$$ $$\gamma+2k=\gamma+k$$ $$2k=k,$$ which is a contradiction.  I'd like to know whether my proofs are correct or not, and if they are, whether they're rigourous enough. It would also be great to see alternative ways of proving these.  Thank you in advance.


I have to show that, if a function $f:\mathbb R\to\mathbb R$ is differentiable, it is also continous. $$\lim_{h\to0}\frac{f_{(x+h)}-f_x}{h}=f'_x\space\space\space\space\forall x\in \mathbb R$$  To show:  $$\lim_{h\to 0} f_{(x+h)}-f_x=0\space\space\space\space\forall x\in \mathbb R$$  I do not know hot to show that. My first thought was to set $h\to 0$: $$\lim_{h\to 0} f_{(x+h)}-f_x=f_{(x+0)}-f_x=f_x-f_x=0?$$ But i think this is not a proper proof. Can somebody help me? Thank you

I have a question, to aid my understanding, about the proof that differentiability implies continutity.$\mathstrut$    Differentiability Definition  When we say a function is differentiable at $x_0$, we mean that the limit:  $$f^{\prime} (x) = \lim_{x\to x_0} \frac{f(x) - f(x_0)}{x-x_0}$$ exists.  Continuity Definition  When we say a function is continuous at $x_0$, we mean that: $$\lim_{x\to x_0} f(x) - f(x_0) = 0$$  Theorem: Differentiability implies Continuity: If $f$ is a differentiable function at $x_0$, then it is continuous at $x_0$.  Proof:  Let us suppose that $f$ is differentiable at $x_0$. Then $$ \lim_{x\to x_0} \frac{f(x) - f(x_0)}{x-x_0} =  f^{\prime} (x) $$  and hence  $$ \lim_{x\to x_0} f(x) - f(x_0) = \lim_{x\to x_0} \left[ \frac{f(x) - f(x_0)}{x-x_0} \right] \cdot \lim_{x\to x_0} (x-x_0) = 0$$  We have therefore shown that, using the definition of continuous, if the function is differentiable at $x_0$, it must also be continuous.  My Question  The proof seems to execute the following steps:   Assume the function is continuous at $x_0$ Show that, with little algebra, we can change this into an equivalent question about differentiability at $x_0$. With this little bit of algebra, we can show that if a function is differentiable at $x_0$ it is also continuous.   What I am slightly unsure about is the apparent circularity. In my mind it seems to say, if a function is continuous, we can show that if it is also differentiable, then it is continuous. Rather than what I was expecting, namely, if a function is differentiable, we can show it must be continuous.  Hopefully my confusion is clear. Any help will be greatly appreciated.


I'm new to physics. And I have curiously wondering about the relationship between matter and energy. From what I understand, one can create the other, but is it truly creating or just aiding in the process?

I understand the energy and mass can change back and forth according to Einstein. It is fluid; it can go from one to the other. So, what keeps mass from just turning into energy? Is there some force holding a subatomic particle together? What keeps mass in it's state? I hope this is not a silly question but I am clueless. Thanks


I use pixel inspector in Arcgis  to find cell values. this is very helpful tool in arcgis. I wanted to know if there is such a tool in Qgis which can help me to find the cell values(Except the identify tool).

I was wondering how to check the value of a pixel at a mouse click in QGIS (as of 2.4).  In ArcGIS, the Identify tool does the job for both rasters and vectors. However, in QGIS, the Identify tool seems to be greyed out when only one raster layer is loaded.


I have been searching through meta trying to find out what the exact number of views is that constitutes "low views."  Is there an algorithm that determines when the Tumbleweed badge is programmatically awarded?  Or does someone go through questions and manually award the badges to questions they think meet the criteria?

Formerly List of all badges with full descriptions.  What are badge name's requirements? Why didn't I get badge name ? Which badges can I earn multiple times?    Jump to:                    Note: Some badges are awarded based on score. The term score means the total number of upvotes minus the total number of downvotes.  Any badge with a *** next to it is one of 20 badges that count towards the  displayed on a moderator candidate in an election. The candidate score is a total of 40 points: the first 20 are awarded based on the user's rep divided by 1000 and rounded down; the second 20 represents the total number of unique badges earned of the 20 that count. Note that if the same badge is earned multiple times, it will only count once towards the candidate score.  Any badge with a "(retired)" next to it is no longer awarded, but is retained by users who previously earned them. See  for more info on what it means for a badge to be retired.       Visit the  of the  on any site to see a complete list of badges that you can filter by earned, unearned, or type.


Hello I have a friend who is traveling form Manila to the Dominican Republic making a change of planes in Istanbul and Madrid. Does he need to get a visa to transit through Istanbul?

I have an Indian passport and am planning to visit Germany with a valid visa. To book a flight for Germany (Mumbai – Dusseldorf), I came across some connected flights that stop at Istanbul.  Do I need to have visa for Turkey?  This is the first time I am travelling outside my country, and any information on this will be helpful.


I am unable to understand that why do we have two ways to multiply two vectors? (viz. Dot product and cross product) How do we even know when to use which product? Is it analogous to anything with numbers? Do we multiply numbers in two ways?  Or is this concept of multiplication really just another unrelated independent operation unfortunately named multiplication due to lack of alphabet, maybe?  Basically, my question is why do we have two ways for multiplying vectors and how whoever thought of it, thought that we needed two ways?

Most questions usually just relate to what these can be used for, that's fairly obvious to me since I've been programming 3D games/simulations for a while, but I've never really understood the inner workings of them... I could get the cross product equation as a determinant of a carefully-constructed matrix,   but what I want to ask is... How did the dot and cross product come to be? When were they "invented"? Some detailed proofs? Did someone say: "Hey, wouldn't it be nice if we could construct a way to calculate a vector that is perpendicular to two given operands?"  Basically, how/why do they work?  I would appreciate explanations, links to other explanations, other web resources... I've been searching the Internet lately for explanations, but most of them are on how to use it and nothing that really gives substance to it.


I was thinking of random math problems to myself when I came across this:  $x^2 = 2^x$  It seemed very simple at first, but after trying multiple ways to solve it, I had no idea what to do.  So, I began doing a lot of searches for this problem, and I found out that in order to solve $x^2 = 2^x$, you have to use some function of which I have never heard before. So, I have three main questions regarding this problem.  1) is it possible to solve $x^2 = 2^x$ arithmetically? If so, how would one do so? If not, why not? In other words, why would it be impossible to solve this problem arithmetically?  2) Why is it that addition and multiplication are commutative, but exponentiation is not? I understand not all forms of multiplication in mathematics are non-commutative, but for the sake of this problem, exponentiation feels like the "next step" right after multiplication. Here's what I mean by this:  Addition is just adding a number to a number.  Multiplication is just adding a number $N$ times to a number.  Exponentiation is just multiplying a number $N$ times by a number.  3) Would it be possible to invent your own function to solve $x^2 = 2^x$, or rather, $x^y = y^x$? And after you found a way to represent your answer, how could you go about evaluating your answer without using a calculator?  If anything doesn't make sense above, I can do my best to clarify. I also know some of these questions have been asked before, but I didn't really understand any of the answers, and the questions weren't as specific as mine.

How to solve this equation $$x^{2}=2^{x}$$   where $x \in \mathbb{R}$.  Por tentativa erro consegui descobri que $2$ é uma solução, mas não encontrei um método pra isso. Alguma sugestão?(*)  (Translation: By trying different values I've found that $2$ is a solution, but I couldn't find any method to this though. Any suggestions? )


** Term-control chars edited out:  Script started on 2017-12-01 06:51:43-0500 /etc/bash.bashrc ~root/.bashrc declare -x PATH="/root/sbin:/usr/local/sbin:/usr/sbin:/sbin:/root/bin:/root/.emacs.d/term-cmd:/usr/local/bin:/usr/bin:/bin:/snap/bin:/root/Scripts" declare -x HOME="/root"  bash # passwd bunky  Current Kerberos password:   New password:   Retype new password:   Current Kerberos password:   Current password:   passwd: Authentication token manipulation error  passwd: password unchanged   bash exit #################################   1) I have never set up Kerberos.  Why is passwd asking for "Current Kerberos password?  2) As root, I should not require to know 's "current password".   3) In fact, an unknown problem with the user's old password is the reason for the whole exercise.

I am logging in to my Ubuntu Server using my username. Once I am logged in I am typing passwd command. Entering a new password but a second after getting following error messages:  passwd: Authentication token manipulation error passwd: password unchanged   What is wrong here? How can I change my password otherwise if I don't have access to that server physically, i.e. I am connecting remotely with ssh using terminal.


Which Stack Exchange should I use for cyber security questions or in other words, is there a Stack Exchange like Stack Overflow, but for ethical hackers? In my case, I'm starting into the cybersec world and as a beginner I get to tons of difficulties and mostly errors with the linux ecosystem (Kali Linux) and more over with software that's related to cybersec. EXAMPLE:  Having problems installing certain packages for "Kali Linux", like wifite2 or hashcat.  Getting errors no one in the tutorials is getting when installing a certain package which doesn't come with the OS...  Want to learn how a certain software is properly used "hashcat" for example.  Having difficulties understanding the way a certain software works..

Is there any SE Site where we can post questions related to Hacking (Networking)?


While solving the question of  a question arrived in my mind; the question was  Everyone knows the divisibility rule of $13$.  Test for divisibility by $13$: Add four times the last digit to the remaining leading truncated number. If the result is divisible by 13, then so was the first number.   For Example : $$50661$$ $$5066+4=5070$$ $$507+0=507$$ $$50+28=78$$   and $78$ is $6\times13$, so $50661$ is divisible by $13.$  Please help me!!!

Given a number presented in decimal form $n=\sum_{k=0} d_k10^k$ there are some nice thumb rules to decide whether it is divisible with a prime number  $p\in\{7,11,13,17,19,23,29\}$.   For each of this numbers there is a number  $a_p$ such that $p|n\iff p|(a_p\cdot d_0+\sum_{k=0} d_{k+1}10^k)$.  $a_7=-2,\;a_{11}=-1,\;a_{13}=4,\;a_{17}=-5,\;a_{19}=2,\;a_{23}=7,\;a_{29}=3$  E.g. $\;19\cdot 17=323$ and $32+2\cdot 3=38=2\cdot 19$ and $32-5\cdot 3=17$.  Is there a number $a_{31}$ that works the same way? Or $a_p,\;p\ge37$?


For some reason, Lydia won't wear her armor when I give it to her. I've tried just your basic steel stuff, Elven boots and gauntlets, and a myriad of other things and none of them equip. When I bring up her inventory, the shield, jewelry, and weapon I've given her has a little arrow next to it to show it's equipped. This arrow doesn't appear on any of the armor items. I've tried taking the items away from her and giving them back; removing everything except armor from her inventory; telling her to leave and then making her follow me again—none of them have worked.   I'm starting to think she just hates me (I do scream expletives at her every time she blocks a doorway or does something else stupid). But seriously, she needs to put on her armor. Help please?

So, I was interested in seeing if I could get Iona to wear some more common clothes around the house.  I pretty much just leave her there most of the time anyway, so there's no point in her being always dressed for battle.  I couldn't seem to get her to un-equip her standard armor, and she wouldn't put on regular clothing or lesser armor while it was equipped.  So, after I finished leveling and perking up my pickpocketing, I stole the Steel Armor straight off her back.  After that, I gave her some more suitable house attire (via "Follow me..." -> "I need to trade...") which she gladly put on.  However, when I later left and returned to the house, I found her wandering around in her undergarments!  I checked her inventory, and found the clothes I'd given her were still there and her armor wasn't.  So, she had no good reason not to be dressed in what had been handed to her.  Later, I figured out this continues to happen even if I leave a full set of Legendary-quality Dragonscale Armor with her.  And, later on... I found out this is also the case with Lydia and Jordis.  They'll all wear their clothes immediately after being given them.  But if I leave them at home, I'll return to find them bare.  Is this a known bug?  Is there any way around it without using the PC-only console?


What is the best way to parse non-digit strings e.g. "twenty two"->22 to integer or double values in python ? Especially what is the best way to detect that region if there are additional words in a sentence.   Thanks

I need to convert one into 1, two into 2 and so on.  Is there a way to do this with a library or a class or anything?