I was given a project of a some developer and during looking throuhg the code I found such code:  public interface IPackage {     void @Do(); }    I've just seen usage of @ in context with strings. But what does that mean in such context? Can somebody explain please? Thank you in advance!
I discovered that you can start your variable name with a '@' character in C#.  In my C# project I was using a web service (I added a web reference to my project) that was written in Java. One of the interface objects defined in the WSDL had a member variable with the name "params". Obviously this is a reserved word in C# so you can't have a class with a member variable with the name "params". The proxy object that was generated contained a property that looked like this:  public ArrayList @params {     get { return this.paramsField; }     set { this.paramsField = value; } }   I searched through the VS 2008 c# documentation but couldn't find anything about it. Also searching Google didn't give me any useful answers. So what is the exact meaning or use of the '@' character in a variable/property name?
Setting up SFTP to log in to server with Filezilla I have an ec2 instance on AWS which already installed a few Wordpress-es in it.  I want to set things up to let more people handle their own projects, with me also being able to go into the server using terminal if I still want to.  I have been following tutorials such as  and a few others.  I figured all of them just teach users how to sftp into their own home folder, also the steps keep saying addUser but some users already existed and removing them might cause some issue.  How can I give existing users the permission to use SFTP for Wordpress projects?  Let's say all my Wordpress projects are already under /var/www/ which has already been set up with www-data:www-data.  Really new with setting things like this.  Thanks in advance for any help. Find the value of $\sin\frac{2\pi}{7}+\sin\frac{4\pi}{7}+\sin\frac{8\pi}{7}$ Merging arrays with the same keys Is SHA-256 secure as a CTR block cipher? Generate a 256-bit random nonce. XOR it with a 256-bit reusable symmetric key. This is x.  We represent numbers in simple binary instead of a counting function. 0 in dec = [256 zeros] in binary, 1 = [255 zeros]1, 23092348 = [241 zeros]1011000000101110001111100, etc.  For each nth block needed for the length of the plaintext, XOR x with n and hash it with SHA-256 to form b[n].  Let p[n] be the nth 256-bit block in the plaintext and c[n] be the nth block in the ciphertext. Then c[n] := b[n] XOR p[n].  Send the unencrypted nonce along with the ciphertext.  To decrypt c[n], XOR it with b[n] to retrieve p[n].  Is this secure? If so, then why do we need AES-256?  If this is not secure, then is there any mode of operation for which SHA-256 is secure as a block cipher? Specifically, it would need to be used in cipher feedback, output feedback, or any other mode that only uses the cipher in the encryption direction. Meaning of $\int \phi^\dagger \hat A \psi \:\mathrm dx$ While analysing a problem in quantum Mechanics, I realized that I don't fully understand the physical meanings of certain integrals. I have been interpreting:    $\int \phi^\dagger \hat A \psi \:\mathrm dx$  as "(square root of) probability that a particle with state $|\psi\rangle$ will collapse to a state $|\phi\rangle$ when one tries to observe the observable corresponding to $\hat A$" $\int \phi^\dagger  \psi \:\mathrm dx$ as "(square root of) probability that a particle with state $|\psi\rangle$ will collapse to a state $|\phi\rangle$".   All integrals are over all space here, and all $\phi$s and $\psi$s are normalized.  Now, I realize that  interpretation of the first integral doesn't really make sense when put side by side with the second one.   For example, when $|\phi\rangle$ is an eigenstate of $\hat A$, I get two different expressions for "the square root of probability that one will get the corresponding eigenvalue of $\psi$ when one tries to observe the observable corresponding to $\hat A$". As far as I can tell, $\int \phi^\dagger \hat A \psi \:\mathrm dx \neq\int \phi^\dagger  \psi \:\mathrm dx $, even if $|\phi\rangle$ is an eigenstate of $\hat A$. I am inclined to believe that the second integral is the correct answer here (it comes naturally when you split $|\psi\rangle$ into a linear combination of basis vectors). But I am at a loss as to the interpretation of the first integral.  So, my question is, what are the physical interpretations of $\int \phi^\dagger \hat A \psi \:\mathrm dx$ and $\int \phi^\dagger  \psi \:\mathrm dx$?  (While I am familiar with the bra-ket notation, I have not used it in this question as I don't want to confuse myself further. Feel free to use it in your answer, though) Help with multirow table I am trying to wrap text in the multirow column (1st one) and only have the vertical lines inside the table if that makes sense.   Can anyone help me? `  \begin{table*}[!htbp] \centering \renewcommand{\arraystretch}{1.4} \begin{tabular}{|c| p{2cm}|c|c|c|c|} \cline{3-6} &amp;&amp;\multicolumn{2}{c|}{\textbf{Gravité du Dommage G1}} &amp; \multicolumn{2}{c|}{\textbf{Gravité du Dommage G2}}\\  \cline{3-6} &amp;&amp;\textbf{Fréquence F1} &amp; \textbf{Fréquence F2} &amp; \textbf{Fréquence F1} &amp; \textbf{Fréquence F2}\\ \hline \multirow{ 2}{*}{\textbf{Probabilité Occurence O1}}&amp;\textbf{Possibilité Evitement P1}&amp;&amp;&amp;&amp;\\ \cline{2-6} &amp;\textbf{Possibilité Evitement P2}&amp;&amp;&amp;&amp;\\ \hline \multirow{ 2}{*}{\textbf{Probabilité Occurence O2}}&amp;\textbf{Possibilité Evitement P1}&amp;&amp;&amp;&amp;\\ \cline{2-6} &amp;\textbf{Possibilité Evitement P2}&amp;&amp;&amp;&amp;\\ \hline \multirow{ 2}{*}{\textbf{Probabilité Occurence O3}}&amp;\textbf{Possibilité Evitement P1}&amp;&amp;&amp;&amp;\\ \cline{2-6} &amp;\textbf{Possibilité Evitement P2}&amp;&amp;&amp;&amp;\\ \hline \end{tabular} \end{table*} Questions on "All Horse are the Same Color" Proof by Complete Induction I'm bugged by the following that's summarized on p. 109 of .     False theorem: All horses are the same color.      Proof by induction:      $\fbox{$P(n)$ is the statement: In every set of horses of size $n$, all $n$ horses are the same color.}$   $\fbox{Base Case or $P(1)$:}$ One horse is the same color as itself. This is true by inspection.   $\fbox{Induction Step:}$ Assume $P(k)$ for some $k \geq 1$.   $\fbox{Proof of $P(k + 1) :$}$   Since $\{H_1, H_2, ... , H_n\}$ is a set of $n$ horses, the induction hypothesis applies to this set. Thus, all the horses in this set are the same color.   Since $\{H_2, H_3, ... , H_{n+1}\}$ is also a set of $n$ horses, the induction step likewise holds for this set. Thus, all the horses in this set are the same color too.         Therefore, all $n +1$ horses in $\{H_1, H_2, H_3, ... , H_n , H_{n+1}\}$ are the same color. QED.   The issue the instructor was trying to point out is clearly valid. For the case $n = 1$, there is only ${H_1}$. So this case says nothing about possible overlapping elements of each set of $(n + 1)$, for instance $H_2$ in the above proof.    But it was proposed in the class discussion that this was the only problem. Had you been able to prove $P(2)$ true, then a proof of the above format would have been fine.    My interpretation is that yes, you could prove all horses are the same color, if you can prove that any set of two horses will be the same color. But this format would not work.  Why not? The problem I see is that the above proof is for the existence of at least one particular pair of sets of horses of sizes $n$ and $n + 1$, such that in each set, all horses are the same color.  Particularly when the set of size $n$ is a subset of the set of size $n + 1$.  In order to prove the induction step, don't you need to prove that sets of sizes $n$ and $n + 1$, do not necessarily contain the same, overlapping elements?  You could prove that any horse can be added to a set of 2 horses.  Take the last two, and they must be the same color, and so on.  Wwhatever color the first two happen to be, all other horses must thus be the same color.    Am I misinterpreting the example, or am I making a logical error? Thanks in advance. the largest integer $n$ for which $n+5$ divivides $n^5+5$? When we divide $n^5+5$ by $n+5$, we get a remainder $-620$, i.e., $n^5+5=K(n+5)-620$ , now how to proceed further? Why does the Lasso provide Variable Selection? I had an (extremely minor) identity crisis when I clicked on my username and saw a different identicon than I'd had previously. :)  According to , your identicon is based on a hash of your last known IP address.  Since a user's profile picture part of their identity, I would prefer if my profile picture only changed through deliberate action on my part.  Since the user's IP hash is already saved (the identicon has to be displayed to people even during the unthinkable periods when we're not actively browsing), I propose preserving the first one assigned to a user, and not updating it even if the user's IP address changes.  Are there any upsides to the current behavior that I haven't thought of? How do you get a timestamp in JavaScript? Something similar to Unix's timestamp, that is a single number that represents the current time and date. Either as a number or a string. How do I configure Nautilus to open at my Documents folder instead of my home folder?  I've scoured this site and found answers instructing users to edit the /usr/share/applications/nautilus.desktop file, replacing %U with the path to the desired default directory. I've edited all the variants of nautilus.desktop in the said directory, but none of the edits has an effect. I've checked all the files after editing them to make sure that I saved the edit effectively, and all look good to me.   I've edited every file to read as follows:  Exec=nautilus --new-window /home/judy/Documents   I've also edited the org.gnome.Nautilus.desktop file, just to be sure, with no joy.   I'm running Ubuntu 15.10.  Note: if I enter nautilus /home/judy/Documents from the command line, Nautilus properly opens in the desired directory.  Is there a simple way that I can configure an icon in the launcher bar to run this command and have the Nautilus icon that looks like a metal file drawer?  Thanks. I'm pulling my hair out over this one. Delete all files except specified files/folders using command line? I have a folder containing a lot of folders and different files with the following structures :  NASA │ ├── a │   ├── doc1 │   ├── doc2 │   ├── doc3 │   ├── folder1 │   └── folder2 │ ├── b │   ├── doc1 │   ├── doc2 │   ├── doc3 │   ├── folder1 │   └── folder2 │ ├── c │   ├── doc1 │   ├── doc2 │   ├── doc3 │   ├── folder1 │   └── folder2 │ ├─ x ├─ y └─ z          I want to delete the content of the folder (NASA/) except specified folders and files.   For example I want to keep a folder, b folder and x file.     I tried   :   rm !(a/) -r NASA/   And (as explained in the answer ):  find NASA/ -type f ! -iname "x" -delete   But this is not very straight forward and I have to use a bash script.    Am I missing a more easy way ? How can I do this in a single command? What was the galaxy formation Rust saw before confronting Erol Childress in  S01E08?  It was weird like out of the series. I guess it was some sort of hallucination, a product of Rust's madness or addiction. How to get rid of blank pages in PDF exported from SSRS I have a two-page SSRS report. When I exported it to PDF it was taking 4 pages due to its width, where the 2nd and 4th pages were displaying one of my fields from the table. I tried to set the layout size in report properties as width=18in and height =8.5in.  It gave me the whole table in a single page of PDF, but I am still getting the 2nd and 4th pages blank.   Is the way I am doing it incorrect?  How else can I get rid of those blank pages? Get the size of the screen, current web page and browser window glob() - sort array of files by last modified datetime stamp In Star Trek II: The Wrath of Khan (the one from 1982, not the recent remake), Khan yells "This is Ceti Alpha V!" and they're all like this is a big surprise, we didn't know.  If they had previously charted the planet, wouldn't the computer have told them the planets weren't quite where they should be based on earlier visits? I mean, we can predict the next hundred transits of Venus, shouldn't 23rd century explorers be able to predict where the Ceti planets are less than twenty years after their first visit? How to carry audio over SSH? Is there a way to carry audio over ssh?   Say after connecting to remote machine through ssh -X I opened a browser and want to watch a youtube video. Currently I could only able to watch the video without any audio. But I want to hear the audio too. How to do that? What are the differences between Holmes, Moldvay, and Mentzer D&D?