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How should ip2long converted IP's be stored in MySQL?
How to find all graph isomorphisms in FindGraphIsomorphism I wonder how a researcher send an unsolicited email to another one asking for feedback to their work. I guess it will be something like this?  Hello Dr. X To introduce myself, I am Y, in institute Z. I'm sorry if this email is not convenient at this time, but my work about A is highly relevant to your work in B, so I think it will be interesting to you too. If possible, can you take a look at it and tell me what you think? Here is the link:  Thank you for your reading, hope you enjoy it.  I wonder if the summary/abstract should be included in the email too, since the principle for  is to show everything you know about it. Maybe it's not necessary, since the title of the link should prove its interestingness nevertheless? I'd like to have your confirm. I'm also interested in the case where Y has no Z, and the link is just a collection of observations posted in a blog, not a full paper with proper citation and literary review. It is possible that the observations may have been covered in the field, but Y isn't aware of that yet. I also think that if the link is interesting enough, then putting a tracking method in there is fine too? Even if they finds out, they wouldn't feel insulted either, because they find that the link is indeed interesting.  Related: •  •  • How can I rename many files at once? Why are some faces in my mesh darker? Get name of caller function in PHP? Is there a PHP function to find out the name of the caller function in a given function? Determine whether a number is prime How do I determine if a number is prime?  I'm writing a program where a user inputs any integer and from that the program determines whether the number is prime, but how do I go about that? I am currently in the process of learning how to prove statements by induction. For the most part, I understand but I am at most clueless when it comes to prove some inequalities.  For example, I am having a hard time proving that: $n &lt; 2^n$ is true. (Even if it's clear that it is indeed true!)  In the induction step, I am stuck with: $n + 1 &lt; 2^{n + 1}$  I don't know what would be the assumption I should make from this statement.  Anyone could point me in the right direction? Thanks! Are the hoses in toilets in Asia something I should know about? I have noticed random bits of hose without proper fittings before I think for example in India and just assumed they are for use by the cleaners or for filling the water jug in .  But Now I'm travelling in Malaysia and Singapore and there are more western toilets than squat toilets in the places I've been yet proper hoses with proper fittings are very common in toilets:  (Hose next to a Western style toilet in my hostel in Chinatown, Kuala Lumpur.)  At one place in Singapore there were even signs on each cubicle door stating whether it contained a western or squat toilet, but also whether there was a hose! (I didn't take a photo of the sign, unfortunately)  This makes me think there is a use for the hose for clients, not just cleaners. But for what purpose? Should I know how to use it as a tourist? Please tell me it's not a kind of alternative to a bidet!  Possibly related is the fact that many toilet floors are awash with water. This can be a big problem if you're not wearing waterproof shoes or have to lower your trousers and keep them dry. Other than this toilets are pretty clean and I've seen both the hoses and the wetness in what I would regard as somewhat "fancy" places. What is the correct way to completely remove an application? I've searched the net for such information and found different command lines, like these ones:  sudo apt-get remove application sudo apt-get remove application*  sudo apt-get remove --purge application sudo apt-get remove --purge application*  sudo apt-get purge application sudo apt-get purge application*   So, what is the correct way? Is it necessary to use that "*"?  After that, I also found these commands:  sudo updatedb sudo locate application sudo rm -rf (file/folder name) When clicking &quot;edit&quot; I see:  Your edit will be placed in a queue until it is peer reviewed. We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.  Like:     Likewise, when I am not logged in, clicking &quot;improve this question&quot; or &quot;improve this answer&quot; shows:  You are not . Your edit will be placed in a queue until it is .  And when I click 'Save', I get:  Thanks for submitting an edit. It is only visible to you until it's been approved by trusted community members  Like:     Who can suggest an edit? Where do suggested edits go? Who can vote on a suggested edit? How do suggested edits get reviewed? Can I earn reputation? What about abuse or bad edits? Sometimes the Community user approves or rejects my edit. Why is that? When can I not suggest an edit? Is there a minimum change requirement for a suggested edit? How do I check my suggested edit history? I disagree with the reasons why my suggested edit was rejected. What can I do? How do I know whether there are edits waiting for review? Someone suggested an edit to my own post, and the reviewers took the wrong action. What can I do? Are tag wikis included in this scheme? What do the &quot;Improve Edit&quot; and &quot;Reject and Edit&quot; buttons do? Why are apparently valid links to rejected edits resulting in 404 errors?   For more information about editing, see &quot;&quot; in the . Going to Pakistan in 3 weeks time but my NICOP is expired and my son's hasn't arrived yet My NICOP is expired and I have already booked a flight to Pakistan via Qatar Airways. My wife has a valid NICOP card but my 5 years old child  has never had a NICOP or any other Pakistani ID card other than the British passport. I have made an appointment for next Monday to renew my NICOP and apply for my child's new NICOP card. My question is, what if the cards of my child and mine don't arrive in time, can we still travel to Pakistan, given that we have the receipts as a proof of application? Google Sheets Customize View Using Create Custom Menu and Hiding/Showing Specifc Columns Trying to determine a way that I can use a custom menu (.createMenu) with views that will allow me to show / hide specific columns.  I need the capability to pick specific multiple columns and not ranges.  In the example below how can you pick a custom view from the menu (say "Customer Info") that will only show columns A, B, C, and H?  Maybe another view could show "Financial". We've just been learning about complex numbers in class, and I don't really see why they're called numbers.  Originally, a number used to be a means of counting (natural numbers).  Then we extend these numbers to instances of owing other people money for instance (integers).  After that, we consider fractions when we need to split things like 2 pizzas between three people.  We then (skipping the algebraic numbers for the purposes of practicality), we use the real numbers to describe any length; e.g. the length of a diagonal of a unit square.  But this is when our original definition of a number fails to make sense- when we consider complex numbers, which brings me to my main question: what is a rigorous definition of 'number'?  Wikipedia claims that "A number is a mathematical object used to count, label, and measure", but this definition fails to make sense after we extend $\mathbb{R}$.     Does anyone know of any definition of number that can be generalised to complex numbers as well (and even higher order number systems like the quaternions)? Is there a C++ decompiler? Is adjoint of singular matrix singular? What would be its rank? Let $A$ be a square and singular matrix of order $n$.  Is $\operatorname{adj}(A)$ necessarily singular? What would be the rank of $\operatorname{adj}(A)$? Use of substitution into the integral $\int_0^2 \frac{\arctan x}{x^2+2x+2}dx$ This question: got some attention, but I didn't understand anything of it. Now I looked at the solution of the book and there is given the hint to use the change of variable $$x=\frac{1-t}{1+2t}$$ Could you please explain how one could think of such substitution? Is there some intuition behind this? Also after I used the substitution I got: $$\int_{-1/5}^1\frac{3\arctan\left(\frac{1-t}{1+2t}\right)}{5t^2+8t+5}dt$$ How can I finish this using the hint from the book? How can I determine the name of the Bash script file inside the script itself?  Like if my script is in file runme.sh, then how would I make it to display "You are running runme.sh" message without hardcoding that? How to read a single character from the user? For each $x,y,z∈\mathbb N$, if $x<y$ then $x+z<y+z$ Inner product of two continuous maps is continuous Let f,g be continuous maps of S in $\mathbb{R}^n$, to $\mathbb{R}^m$. Show the inner product h(x) = $\langle f(x), g(x)\rangle$ is continuous.  My attempt: Since f,g are continuous, their product is a continuous mapping, so for $\epsilon \gt 0\: t.e\:  \delta \gt 0$ such that $\parallel x - a\parallel \lt \delta $ implies $\parallel \langle f(x),g(x)\rangle - \langle f(a)g(a)\rangle \parallel \le\parallel f(x)g(x) - f(a)g(a)\parallel \lt \epsilon$ by schwartz inequality.