How to track traffic flows to each IP on home network?
How to monitor bandwidth use of each device on wifi network
Is there a (La)TeX distribution running on iPad? What is the difference between a "proof by contradiction" and "proving the contrapositive"? Intuitive, it feels like doing the exact same thing. And when I compare an exercise, one person proves by contradiction, and the other proves the contrapositive, the proofs look almost exactly the same.  For example, say I want to prove: $P \implies Q$ When I want to prove by contradiction, I would say assume this is not true. Assume $Q$ is not true, and $P$ is true. Blabla, but this implies $P$ is not true, which is a contradiction.  When I want to prove the contrapositive, I say. Assume $Q$ is not true. Blabla, this implies $P$ is not true.  The only difference in the proof is that I assume $P$ is true in the beginning, when I want to prove by contradiction. But this feels almost redundant, as in the end I always get that this is not true. The only other way that I could get a contradiction is by proving that $Q$ is true. But this would be the exact same things as a direct proof.   Can somebody enlighten me a little bit here ? For example: Are there proofs that can be proven by contradiction but not proven by proving the contrapositve? 3 more votes from other users are needed to close this question.   This is the message I got hovering the mouse over close voting tab.   I wonder can we begin any sentence with a numeric value? Is it good practice? Securing WMS against unauthorized access? In a project the customer wants the images of the WMS to be secured against unauthorized access.   What are the common solutions to realize that?   Are they compatible with the OGC-standards? How come unpolarized light does not undergo destructive interference? Trying to keep track of the updates to all the great, user-developed add-ons is fairly frustrating (at least for me). Is there currently a centralized resource where all these amazing add-ons are kept and updated in one location?  If there isn't such a resource, would it be possible to have blender query the collection of installed add-ins and then iterate through on-line references looking at version #'s for add-ins?  Since, as far as I know, it hasn't been done...I have to ask if there are any major flaws in the concept. Of course, in my dream scenario, there would be a "voting" front-end that would allow users to see what the most popular and useful add-ons are and where you don't have to read pages (and pages) of threads. Stored Procedures, MySQL and PHP The question is a fairly open one. I've been using Stored Procs with MS SQLServer for some time with classic ASP and ASP.net and love them, lots.  I have a small hobby project I'm working on and for various reasons have gone the LAMP route. Any hints/tricks/traps or good starting points to get into using stored procedures with MySQL and PHP5? My version of MySQL supports Stored Procedures. Are there any   editors for ? Perhaps something similar to    but for PGF/TikZ?   If there is no WYSIWYG editor for this tandem, is there one perhaps that allows the user to easily generate PGF/TikZ templates?  Alternatively, how can I most easily generate PFG/TikZ code from a visual conception? Do people mostly code their PGF/TikZ graphics from scratch? Copy skype chat history to text files? I'd like to convert my Skype chat history to a collection of text files for archival purposes.  Ideally, I'd like to have a command (e.g. script or app) so that I could do this on a regular basis.  Any one have any idea on how to go about doing this? How can I prove that $2017 \mid 1^{2017}+2^{2017}+\dots+2017^{2017}$? I tried proving it with the use of modulo, however it was to no avail. Afterwards, I  tried researching, for possible theorems, that may help, but that bore no fruit, either. Can you guys please help me proving it, as I am stuck? Thanking you in advance. Execute command from file in current shell I want to executed command from file (which is script) in current shell in terminal.  Example: I have file ch_dir contains following:  #!/bin/bash cd /usr   Now if I execute file usually as following then it executes commands in different shell:  pandya@pandya-desktop:~$ ./ch_dir pandya@pandya-desktop:~$   Here cd /user is executed in different shell.  But I want to execute in Current shell. How do I do that?  Note: Here cd is only used to explain. Question's aim is to execute any command in current shell Why did It not do this to The Losers? Proving $f(x,y,z)=\big(\frac{x}{a+x+y+z}, \frac{y}{a+x+y+z}, \frac{z}{a+x+y+z} \big)$ is injective Let $a\in \mathbb{R}$, $a\neq 0$, and $E=\{(x,y,z)\in \mathbb{R}^3:a+x+y+z\neq 0\}$ and $f:E\rightarrow \mathbb{R}^3$ defined by $$ f(x,y,z)=\big(\frac{x}{a+x+y+z}, \frac{y}{a+x+y+z}, \frac{z}{a+x+y+z} \big) $$ Show that $f$ is injective.    I've been trying to prove it directly by showing that if $f(x_1,y_1,z_1)=f(x_2,y_2,z_2)\Rightarrow$ $x_1=x_2, y_1=y_2,z_1=z_2$. But I get a system of equations which I'm find difficult to deal with. Any help would be greatly appreciated. Convergence of $\sum_{n=1}^\infty{\left(\sqrt[n]{n}-1\right)}$ What forces affect the value of my ETF? Was Hogwarts named such because of a connection to warthogs? Was Hogwarts named 'Hogwarts' because of a connection to warthogs?  Or was it named for hogs and warts separately, or something else entirely? How to deal with variable income in the budget We have a budget planned out for various categories, and in order to make ends meet we count on child support for my wife's child from a previous marriage.  However, lately we have not been receiving this amount.  How do we deal with this in the budget?    My wife has just been "borrowing" it from our savings, but I don't think that is reasonable given that I find it highly unlikely we will ever be able to recover it.  On the other hand, she doesn't think it reasonable to cut out of her budget and cutting it out of the budget for the kids (which is where it really should be going!) isn't reasonable either. Can't reach wi-fi signal on Ubuntu, but can do it on other OS/devices (ath9k) Reverse / invert a dictionary mapping How to Store Fresh Herbs