Save multiple outputs to csv file
Can you recommend a Java library for reading (and possibly writing) CSV files?
Writing a Virtual Printer in .NET Can black holes be created on a miniature scale? A black hole is so powerful to suck everything into itself. So is it possible that mini black holes can be created? If not then we could have actively disproved the rumors spread during LHC experiment. Calculate the product of distances for a line perpendicular to hyperbola Let us have a hyperbola $\frac{x^2}{a^2} - \frac{y^2}{b^2} = 1$ and assume the normal at P meets the transverse (horizontal) axis $AA'$ in $G$ and the conjugate (vertical) axis $BB'$ in $g$. Assume CF be perpendicular to the normal from the center.   Find $\frac{PF \cdot PG}{CB^2}$ Find $PF \cdot Pg$   How can I solve the question in least amount of steps?  My attempt:  I first formed the equation of the normal and then I found out the points where it cuts the conjugate and transverse axis. After finding these points I used distance formula to find the distance required and convert it in the form that the question asked. But its a long method and took lot of steps Is there an easy way to show which spheres can be Lie groups? I have two expressions of type Expression&lt;Func&lt;T, bool&gt;&gt; and I want to take to OR, AND or NOT of these and get a new expression of the same type  Expression&lt;Func&lt;T, bool&gt;&gt; expr1; Expression&lt;Func&lt;T, bool&gt;&gt; expr2;  ...  //how to do this (the code below will obviously not work) Expression&lt;Func&lt;T, bool&gt;&gt; andExpression = expr AND expr2 Exclude menu item from the collapse of bootstrap 3 navbar If photons have no mass, how can they have momentum? What do I do if I don't have a META-INF folder or minecraft.jar? I have looked all over the Internet for solutions but I have got nothing.  I want to install the minepainter mod but I need a META-INF folder and a minecraft.jar. Which Wifi Channel should I use? Very confused.  I'm using inSSiDer, WiFi Overview 360 and Wifi Analyzer apps to try to determine the best wifi channel to use. Assuming all channels are in use and there are about 20 different users in close proximity...  Q1: Signal Strength    If all channels are in equal use, do you select a channel where others that use it have the lowest signal strength?  I'm guessing that a higher signal strength means that it's from a router from your closest neighbour and you want to avoid that.  Is that the case?  Does lower signal strength mean the person using it is further away and therefore less likely to interfere with your signal? If 2 people are on channel 1 and have high signal strength and 2 people are on channel 11 and have low signal strength, do you choose channel 11?  Assume 6 cannot be used.    Q2: Signal Strength Weighted Against Number of People    What is the impact of signal strength compared to number of people using channel?  If 1 person is on channel 1 with very high signal strength and 2 people are on channel 11 with low signal strength, do you choose channel 11 over 1?  Assume 6 cannot be used?    Q3: Channel Overlap    If, for example, I had 11 routers sitting on top of each other, each set to a different channel, I'm guessing channel 1 and 11 would be the least interferred.  Is that right?  People go on about the fact that only channel 1, 6 or 11 should be used (in US) as they don't overlap but surely that statement is wrong.  Yes, if only 3 people were using Wifi, the best channels to use would be 1, 6 and 11 as they don't overlap but in practice, there are about 20 people using the channels in the same area.  What do you do in that scenerio.  Do you go for the shoulder channels if all channels are being used equally with equal strength?    Q4: Auto Channel Select    Do routers set to auto channel select only choose between 1, 6 and 11?  How do they make the choice?  Do they select by choosing channel with lowest other routers and do they factor in signal strengths.  My router auto chooses channel 1 but my closest neighbour is on that channel.  Is that correct.      Q5: Baby Monitors and Wireless Phones    What channels do 2.4 GHz baby monitors and wireless phones use?  No useful info on the internet for them.  Do inSSiDer, etc. pick them up?    Q6: I have access to channel 13.  All other things being equal, am I better to use this over channel 11 as it is further away from the other channels?    Those questions have puzzled me for a number of years and Google is not helping!!  Would really be grateful if someone could give sensible answers to one or all of them.  Thanks, Mike. Every differentiable function $f:R \rightarrow R$ with the property that $(2h)f′(x) =f(x+h)−f(x−h)$ for all $x \in R$ and all $h$ has the form $f(x) =ax^2+bx+c$.  I would like to get some help on this one. Taking partial derivatives was an idea, but is that legal? How would I go about identifying a port, card or connector on my system which I am unfamiliar with?  Where would I find information on what these parts are? What would be the steps I would take in identifying a unknown port or cable?   This question comes up frequently, and the suggested solutions are usually the same. This community wiki is an attempt to serve as the definitive, most comprehensive answer possible. Feel free to add your contributions via edits. CHAOS members have (had?) :     Because they are doing so many edits at once, CHAOS operates in a special mode where editing a title does not bump it to the home page.    I moderate at Writers.SE, and I can attest that this ability would be extremely beneficial to mods as well, and for the same reasons. On beta sites, wide-ranging changes are not infrequent. An established tag might be ruled problematic; a certain class of questions might need cleanup; etc. etc.. When this happens, the ensuing edits flood the front page with old content (frequently the somewhat problematic content the new change has come to address...). Furthermore, since beta sites are much less active than established ones, this flood can drown out recent activity, and then wallow around on the front page for some time.  I propose, then, the implementation of a moderator tool for editing without bumping. The value to beta sites is clear; the danger of abuse, as a mod tool, is nonexistent. Will wolves attack and kill ocelots in Minecraft? I know they kill sheep. I just don't want my cats being eaten. Automatically run commands over SSH on many servers There is a list of IP addresses in a .txt file, ex.:  1.1.1.1 2.2.2.2 3.3.3.3   Behind every IP address there is a server, and on every server there is an sshd running on port 22. Not every server is in the known_hosts list (on my PC, Ubuntu 10.04 LTS/bash).  How can I run commands on these servers, and collect the output?  Ideally, I'd like to run the commands in parallel on all the servers.  I'll be using public key authentication on all the servers.  Here are some potential pitfalls:   The ssh prompts me to put the given servers ssh key to my known_hosts file. The given commands might return a nonzero exit code, indicating that the output is potentially invalid. I need to recognize that. A connection might fail to be established to a given server, for example because of a network error. There should be a timeout, in case the command runs for longer than expected or the server goes down while running the command.   The servers are AIX/ksh (but I think that doesn't really matter. Prove that $n(n^2 - 1)(n + 2)$ is divisible by $4$ for any integer $n$ Prove that $n(n^2 - 1)(n + 2)$ is divisible by $4$ for any integer $n$   I can not understand how to prove it. Please help me. How would neutron matter appear to the naked eye? Neutron matter is matter comprised entirely of neutrons, as it exists in .  Most optical phenomena encountered in everyday life, such as light reflection and spectral absorption (i.e. color appearance) are the result of mechanisms involving electrons.  My simple question: How would a macroscopic sample of matter consisting entirely of neutrons (without electrons) appear to the naked eye?  Assume the matter is  and stable.  Let me add here that I'm not specifically asking about the appearance of a neutron star, as Wikipedia states that it would radiate so much that it appears white. missing $ inserted error for equation I get the missing $ inserted error for the following code:  \begin{equation}  C = $ \frac{2}{\omega^2N^2\mu\pia} $  \end{equation}   I have tried out different changes based on Googling for this error, but nothing seems to help. Any suggestions would be appreciated. I'm adding a title clock in the foot line of a beamer slide, if I compile it with pdfLaTeX it works fine; while the clock doesn't align in the middle vertically if compiling with XeLaTeX. How can I fix this.  Here is my MWE:  \documentclass[10pt]{beamer} \usepackage[font=Times,timeinterval=1]{tdclock} \usetheme{Madrid} \title{Title} \author{Authors} \institute{Institute} \date[\initclock\tddate\ \ \tdtime]{\today} \begin{document} \frame{\titlepage} \end{document} The Boolean modifier is not working When a user without editing privileges suggests an edit to the post, a banner gets displayed until it is reviewed. Can the banner also provide a link to the Suggested edit? For example, I made an edit to a post on Unix&amp;Linux.SE. Can the banner also link to my ?     I know I can access the link through my Profile → Activity → Suggestions. But linking it directly on the face of the post would have immense benefits:  I have been a prolific editor on Ask Ubuntu (my first encounter with Stack Exchange Network) with a lot of Rep derived through Suggestions. I didn't get to know about these suggested edit links until very late (I guess I already had got about 400 edit suggestions approved by the time this came to my knowledge).  This means I didn't know about  when it mattered the most.  I never got to know why my suggestions got rejected because of my ignorance.  This would help reduce the barrier between Reviewers and Editors.  This would also help in case of Anonymous edits. Right now, there is no way an anonymous editor can access it unless the edit gets approved and he comes back to go through the Revision page of that particular post in order to access the Suggested Edit Review link. If the edit gets rejected - it's the end of the road for that anonymous editor. I just made an anonymous edit on one of the SE sites where I don't have an account and already feel like it's the end of the road for me since I just can't access the review link unless it gets approved.    Possibly also expand the banner to mention that they can also access the link to the suggestion via Profile → Activity → Suggestions.