How to get C# Enum description from value?
Getting attributes of Enum's value
Solving $4x = e^x$ without graphing and looking for intersection Bash: What does ">|" do? I have just seen this written down;  $ some-command &gt;| /tmp/output.txt   Vertical pipes are used in standard redirects "piping" the output of one command to another, is &gt;| in fact completely useless as it would be the same as just &gt; in this scenario? Chromatic polynomial properties I have some properties which I do not understand how to form a proof for. Most of them are by induction, which is not my strong point Any help would be fantastic.   Looking at the chromatic polynomial $$P_G(k)=P_{G-e}(k) - P_{G/e}(k)$$  Properties   1.If G has n  vertices then $ P_g(k)$ has degree n and the coefficient of $k^n $ is 1   The signs of $P_g(k) $ alternate If G has q components the smalles non-zero term of $P_g(k)$ is the term in $k^q$ I'm currently working on building a predictive model for a binary outcome on a dataset with ~300 variables and 800 observations. I've read much on this site about the problems associated with stepwise regression and why not to use it.  I've been reading into LASSO regression and its ability for feature selection and have been successful in implementing it with the use of the "caret" package and "glmnet".   I am able to extract the coefficient of the model with the optimal lambda and alpha from "caret"; however, I'm unfamiliar with how to interpret the coefficients.    Are the LASSO coefficients interpreted in the same method as logistic regression? Would it be appropriate to use the features selected from LASSO in logistic regression?   EDIT  Interpretation of the coefficients, as in the exponentiated coefficients from the LASSO regression as the log odds for a 1 unit change in the coefficient while holding all other coefficients constant. Why is plain-hash-then-encrypt not a secure MAC? It seems that even in MAC-then-encrypt systems like SSL, something like HMAC is used rather than a plain hash. Why?   Suppose we use some stream cipher; then why can't we use $Encrypt(m | H(m))$ as the MAC-then-encrypted version of the message? Assuming no bad relations between $Encrypt$ and $H$, what are the possible weaknesses? It seems that in this case we are encrypting the hash with part of a secretly keyed stream cipher keystream, and the hash is secure; does this not fulfil an approximation of the ideal MAC?  This must be somehow bad, since no secure protocol seems to use it. Why? $\mathbb{F}_p[X]/(X^2+X+1)$ is a field iff $p \equiv 2 \bmod 3$ Let $p$ be a prime. Prove that $\mathbb{F}_p[X]/(X^2+X+1)$ is a field iff $p \equiv 2\bmod3$.    So:   If $p \equiv 2 $ mod $ 3$, I have to show that every element of $\mathbb{F}_p[X]/(X^2+X+1)$ has an inverse.  If $\mathbb{F}_p[X]/(X^2+X+1)$ is a field I have to show $p \equiv 2 $ mod $ 3$. I have less than 3000 rep on StackOverflow. Now that the new closing changes are live, I cannot supply a custom off topic message:    I can enter a custom off topic flag message without issue here on meta, though it only has three canned off topic reasons, rather than five.  I'm not sure if this is the same for users with enough rep to vote to close directly, but the lack of a custom message eliminates the ability to use the correct flag reason in some cases.  For example, I wanted to flag , which is simply off topic on SO. However, I can't use a custom message, and none of the canned ones are appropriate.    appears to be the most up to date official information on custom reasons, and indicates that they are remaining in play for now.  supports that.  If this is by design, how should I flag such questions? This is not a case worth bothering the mods over, so I don't want to use a custom diamond attention flag. Site.createPortalUser() returning null in test context The result of a Google search for &quot;error&quot; and &quot;PREP line&quot; is:  &quot;error&quot; &quot;on line&quot;: 439,000,000 results &quot;error&quot; &quot;in line&quot;: 60.600.000 results &quot;error&quot; &quot;at line&quot;: 35,800,000 results  While on is the indisputable number one, in and at have also very many hits. In the following context, which one should I use.  __ the first line you create an instance of XXX and XXX leads to the runtime error __ the last line.  I think, both prepositions are different. Although the word create refers to the action which is executed while runtime, the former part refers to the actual code that is written. In contrast, the latter part is figurative. I don't refer to the written code. The error does not really occur in the code but the code is the representation of the assembly which fails. Thus, I have two bests guess:  On the first line you create an instance of XXX and XXX leads to the runtime error at the last line. In the first line you create an instance of XXX and XXX leads to the runtime error on the last line. All my properties are zero, and my array is zero, even though I have populated them with numbers and objects How can it be that the beginning universe had a high temperature and a low entropy at the same time? The Big Bang theory assumes that our universe started from a very/infinitely dense and extremely/infinitely hot state. But on the other side, it is often claimed that our universe must have been started in a state with very low or even zero entropy.   Now the third law of thermodynamic states that if the entropy of a system approaches a minimum, it's temperature approaches absolut zero.  So how can it be that the beginning universe had a high temperature and a low entropy at the same time? Wouldn't such a state be in contradiction to the third law of thermodynamics? How do Stack Overflow questions appear in Google search results in seconds? Suppose $\int_{[a,b]}f=0,\text{ then }f(x)=0 \forall x\in[a,b]$ Let $a&lt;b$ be real numbers. Let $f:[a,b]\to\mathbb{R}$ be a continuous non-negative function. Suppose $\int_{[a,b]}f=0,\text{ then }f(x)=0 \forall x\in[a,b]$    Proof: Suppose for the sake of contradiction $\exists x_0\in[a,b] \text{ such that } f(x_0)= D&gt; 0$  Since the function is continuous at $x_0$, we have $$\forall \epsilon&gt;0, \exists \delta&gt;0 \text{ such that } |f(x)-f(x_0)|\leq\epsilon\text{ whenever } x\in[a,b]\cap(x_0-\delta,x_0+\delta)$$ choose $\delta=\delta_1$ such that $\epsilon=D/2$, then we can say: $$-D/2 \leq f(x)-f(x_0)\leq D/2$$ $$-D/2 \leq f(x) - D$$ $$f(x)\geq D/2&gt;0$$ This implies that $\int_{[a,b]\cap(x_0-\delta_1,x_0+\delta_1)}f &gt;0$  Now since $\int_{[a,b]} f = 0$. we have  $$\int_{[a,b]}f=\int_{[a,x_0-\delta_1]}f+ \int_{(x_0-\delta_1, x_0+\delta_1)} f + \int_{[x_0+\delta_1,b]}f=0$$ $$\int_{[a,x_0-\delta_1]}f+\int_{[x_0+\delta_1,b]}f&lt;-D/2,$$ but this is a contradiction since $f(x)\geq 0$ and hence $\int_{[a,x_0-\delta_1]}f+\int_{[x_0+\delta_1,b]}f\geq 0$  Is my proof correct? User is suspended network-wide, except not really A user has been active on one of the sites recently, even though they're concurrent suspended network-wide on the rest of the network. How is this possible, and is it possible to evade a network suspension on only one site? Why use definition lists (DL,DD,DT) tags for HTML forms instead of tables? When playing as a spellcaster, is it valid the use of the Ready action to prepare Dispel Magic to counter a spell cast by an opponent? In the same vein, when declaring said action, do I have to specify which spell slot I will use when Readying the Dispel Magic spell? If that is the case, does this tactic nullify an opponent's spell? I get the impression that this is basically turning Dispel Magic into a spell with a casting time of &quot;1 reaction&quot;. Is my reading of the rules accurate? sql server 2008 management studio not checking the syntax of my query Energy conservation of Virtual Particles - Quantum Fluctuation? I (as a middle-school student) was wondering how virtual particles even conserve energy of the entire system? I don't mean just the particle's energy, but conservation with respect to the surroundings?  Let me explain more, Einstein proved that $E = mc^2$ and equivalently, we can say $m = \frac{E}{c^2}$ . We however know mass causes curvature in space-time (gravity well). Now that statement being completely valid we can use Quantum Fluctuation, implying energy and time can be related by the relation:  $\Delta{E}\Delta{t}\approx\frac{\hbar}{2}$ and by that simple relation we can make the following points:   As the energy increases, the time allowed to be "borrowed" decreases, before it gives it back to the universe. As time increases, the energy allowed to be "borrowed" decreases.    These are completely satisfactory points I've made, I believe.  Now, I have read that the vacuum is filled with constantly bubbling virtual particles that get created from the energy "borrowed" by the above relation and is destroyed again, which satisfies the energy conservation laws.   This seems to imply that  in the short time the virtual particle exists, they must have a very small mass which is: $m_{1} = \frac{\Delta{E}}{c^2}$ and using basic classical mechanics rather than GR (for sake of simplicity) we calculate that the gravitational force mediated by this short-lived virtual particle;  $F_{g}= G\frac{m_1 * m_x}{r^2}$   where $m_x$ is an particle\mass in question. Nevertheless since we know the force set upon an object moves the object in a direction, we can say it would increase its kinetic energy by this factor: $F_g = \frac{1}{2}mv^2$ which is equal to $G\frac{m_1 * m_x}{r^2} = \frac{1}{2}mv^2$.  Surely, this implies that every time quantum fluctuations happen, energy of real-particles\masses increases and therefore violates energy conservation, but what prevents this violation from taking place?  If virtual particles are not really present and interact with objects like I thought, how can Hawking radiation (currently a large concept in black hole physics) then be accepted in physics community? Decreasing font size in verbatim How can I modify the following command to make it work?  \newcommand{\code}[1]{\begingroup \fontsize{10pt}{10pt}\selectfont \begin{verbatim} #1 \end{verbatim} \endgroup}   I currently get the following error on the close of the following verbatim block:  ! Undefined control sequence. &lt;argument&gt; ...endgroup ^^M^^M$\eta_{xi} = r_{xi} -                                                    q_i \cdot p_x$ \\^^M$q_i ... l.227     \end{verbatim} 90's book about children climbing a tree and visiting different worlds from there In the 90's I read a book about two children (I think they were siblings, boy and girl) who climbed a tree. At the end they found a door to another world. After some time the (fantasy) worlds switched to another one. Once they got stuck in a world, because the world went on traveling and therefore the door couldn't be reached anymore. They met many curious individuals during their adventures.  It's a completed novel for kids. I've read it in German, but I can't remember if the author was a German one, so it might've been available in English as well. It was a fairly thick book.  EDIT: After some thought I remember a pancake kind of person